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1.
Int J Mol Sci ; 25(13)2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-39000305

RESUMEN

Nitrosyl iron complexes are remarkably multifactorial pharmacological agents. These compounds have been proven to be particularly effective in treating cardiovascular and oncological diseases. We evaluated and compared the antioxidant activity of tetranitrosyl iron complexes (TNICs) with thiosulfate ligands and dinitrosyl iron complexes (DNICs) with glutathione (DNIC-GS) or phosphate (DNIC-PO4-) ligands in hemoglobin-containing systems. The studied effects included the production of free radical intermediates during hemoglobin (Hb) oxidation by tert-butyl hydroperoxide, oxidative modification of Hb, and antioxidant properties of nitrosyl iron complexes. Measuring luminol chemiluminescence revealed that the antioxidant effect of TNICs was higher compared to DNIC-PO4-. DNIC-GS either did not exhibit antioxidant activity or exerted prooxidant effects at certain concentrations, which might have resulted from thiyl radical formation. TNICs and DNIC-PO4- efficiently protected the Hb heme group from decomposition by organic hydroperoxides. DNIC-GS did not exert any protective effects on the heme group; however, it abolished oxoferrylHb generation. TNICs inhibited the formation of Hb multimeric forms more efficiently than DNICs. Thus, TNICs had more pronounced antioxidant activity than DNICs in Hb-containing systems.


Asunto(s)
Antioxidantes , Hemoglobinas , Hierro , Fosfatos , Tiosulfatos , Tiosulfatos/farmacología , Tiosulfatos/química , Hemoglobinas/metabolismo , Hemoglobinas/química , Hierro/metabolismo , Hierro/química , Fosfatos/química , Fosfatos/metabolismo , Ligandos , Antioxidantes/farmacología , Compuestos de Sulfhidrilo/química , Compuestos de Sulfhidrilo/metabolismo , Oxidación-Reducción/efectos de los fármacos , Óxidos de Nitrógeno/química , Óxidos de Nitrógeno/farmacología , Óxidos de Nitrógeno/metabolismo , Glutatión/metabolismo , Animales
2.
Environ Monit Assess ; 196(8): 745, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39017720

RESUMEN

This study investigates real-world carbon dioxides (CO2) and nitrogen oxides (NOx) emissions from diesel (Bharat Stage-IV (BS-IV)) and petrol/gasoline (BS-IV and BS-VI) cars in Indian driving conditions using a portable emission measurement system (PEMS). The paired sample t-test revealed a significant difference ( p < 0.05) in NOx and CO2 emissions among the three types of cars, except for CO2 emissions ( p > 0.05) between BS-IV petrol and BS-VI petrol cars. The highest NOx emission rates were observed in all car types during acceleration (> 1 m/s2) and deceleration (- 2 m/s2). CO2 emission rates were also high during acceleration (> 1 m/s2) for all car types. At low speeds (around 20 kmph), all car types had low emissions of CO2 and NOx, with acceleration and deceleration rates ranging from - 0.5 to 0.5 m/s2. BS-IV diesel cars emit significantly higher NOx emissions compared to petrol cars, especially at vehicle-specific power (VSP) bin 0 (deceleration to idling mode) and during VSP bin 7 (acceleration mode). BS-IV diesel cars emit 228% and 530% higher NOx emissions than BS-IV and BS-VI petrol cars at VSP bins 0 and 7, respectively. CO2 emissions from BS-VI petrol cars were 10% lower than those from BS-IV petrol cars across all VSP bins, indicating moderate reductions. Furthermore, diesel cars emit 140% less CO2 emissions than petrol cars across various VSP bins. The findings highlight the need for cleaner technologies and responsible driving practices to address vehicular emission concerns.


Asunto(s)
Contaminantes Atmosféricos , Automóviles , Dióxido de Carbono , Monitoreo del Ambiente , Gasolina , Óxidos de Nitrógeno , Emisiones de Vehículos , Emisiones de Vehículos/análisis , India , Contaminantes Atmosféricos/análisis , Óxidos de Nitrógeno/análisis , Dióxido de Carbono/análisis , Automóviles/estadística & datos numéricos , Contaminación del Aire/estadística & datos numéricos
3.
Ecotoxicol Environ Saf ; 281: 116664, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38954909

RESUMEN

BACKGROUND: Observational studies have reported associations between air pollutants and brain imaging-derived phenotypes (IDPs); however, whether this relationship is causal remains uncertain. METHODS: We conducted bidirectional two-sample Mendelian randomization (MR) analyses to explore the causal relationships between 5 types of air pollutants (N=423,796 to 456,380 individuals) and 587 reliable IDPs (N=33,224 individuals). Two-step MR was also conducted to assess whether the identified effects are mediated through the modulation of circulating cytokines (N=8293). RESULTS: We found genetic evidence supporting the association of nitrogen oxides (NOx) with mean intra-cellular volume fraction (ICVF) in the left uncinate fasciculus (IVW ß=-0.42, 95 % CI -0.62 to -0.23, P=1.51×10-5) and mean fractional anisotropy (FA) in the left uncinate fasciculus (IVW ß=-0.42, 95 % CI -0.62 to -0.21, P=4.89×10-5). In further two-step MR analyses, we did not find evidence that genetic predictions of any circulating cytokines mediated the association between NOx and IDPs. CONCLUSION: This study provides evidence for the association between air pollutants and brain IDPs, emphasizing the importance of controlling air pollution to improve brain health.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Encéfalo , Fenotipo , Humanos , Contaminación del Aire/efectos adversos , Contaminantes Atmosféricos/toxicidad , Encéfalo/diagnóstico por imagen , Análisis de la Aleatorización Mendeliana , Óxidos de Nitrógeno , Citocinas/genética , Citocinas/sangre , Neuroimagen
4.
Nat Commun ; 15(1): 5447, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38992007

RESUMEN

Air pollution has the potential to disrupt ecologically- and economically-beneficial services provided by invertebrates, including pollination and natural pest regulation. To effectively predict and mitigate this disruption requires an understanding of how the impacts of air pollution vary between invertebrate groups. Here we conduct a global meta-analysis of 120 publications comparing the performance of different invertebrate functional groups in unpolluted and polluted atmospheres. We focus on the pollutants ozone, nitrogen oxides, sulfur dioxide and particulate matter. We show that beneficial invertebrate performance is reduced by air pollution, whereas the performance of plant pest invertebrates is not significantly affected. Ozone pollution has the most detrimental impacts, and these occur at concentrations below national and international air quality standards. Changes in invertebrate performance are not dependent on air pollutant concentrations, indicating that even low levels of pollution are damaging. Predicted increases in tropospheric ozone could result in unintended consequences to global invertebrate populations and their valuable ecological services.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Invertebrados , Ozono , Material Particulado , Animales , Contaminación del Aire/efectos adversos , Invertebrados/efectos de los fármacos , Ozono/toxicidad , Ozono/efectos adversos , Contaminantes Atmosféricos/toxicidad , Contaminantes Atmosféricos/efectos adversos , Material Particulado/efectos adversos , Dióxido de Azufre/toxicidad , Óxidos de Nitrógeno/toxicidad , Polinización
5.
Int J Epidemiol ; 53(4)2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-39018665

RESUMEN

BACKGROUND: The carcinogenicity of air pollution and its impact on the risk of lung cancer is well known; however, there are still knowledge gaps and mixed results for other sites of cancer. METHODS: The current study aimed to evaluate the associations between ambient air pollution [fine particulate matter (PM2.5) and nitrogen oxides (NOx)] and cancer incidence. Exposure assessment was based on historical addresses of >900 000 participants. Cancer incidence included primary cancer cases diagnosed from 2007 to 2015 (n = 30 979). Cox regression was used to evaluate the associations between ambient air pollution and cancer incidence [hazard ratio (HR), 95% CI]. RESULTS: In the single-pollutant models, an increase of one interquartile range (IQR) (2.11 µg/m3) of PM2.5 was associated with an increased risk of all cancer sites (HR = 1.51, 95% CI: 1.47-1.54), lung cancer (HR = 1.73, 95% CI: 1.60-1.87), bladder cancer (HR = 1.50, 95% CI: 1.37-1.65), breast cancer (HR = 1.50, 95% CI: 1.42-1.58) and prostate cancer (HR = 1.41, 95% CI: 1.31-1.52). In the single-pollutant and the co-pollutant models, the estimates for PM2.5 were stronger compared with NOx for all the investigated cancer sites. CONCLUSIONS: Our findings confirm the carcinogenicity of ambient air pollution on lung cancer and provide additional evidence for bladder, breast and prostate cancers. Further studies are needed to confirm our observation regarding prostate cancer. However, the need for more research should not be a barrier to implementing policies to limit the population's exposure to air pollution.


Asunto(s)
Contaminación del Aire , Neoplasias de la Mama , Exposición a Riesgos Ambientales , Neoplasias Pulmonares , Material Particulado , Neoplasias de la Próstata , Neoplasias de la Vejiga Urinaria , Humanos , Masculino , Incidencia , Femenino , Neoplasias de la Vejiga Urinaria/epidemiología , Neoplasias de la Vejiga Urinaria/inducido químicamente , Neoplasias de la Vejiga Urinaria/etiología , Contaminación del Aire/efectos adversos , Neoplasias de la Próstata/epidemiología , Neoplasias de la Próstata/etiología , Neoplasias de la Próstata/inducido químicamente , Material Particulado/efectos adversos , Neoplasias Pulmonares/epidemiología , Neoplasias Pulmonares/inducido químicamente , Neoplasias Pulmonares/etiología , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/inducido químicamente , Neoplasias de la Mama/etiología , Persona de Mediana Edad , Anciano , Exposición a Riesgos Ambientales/efectos adversos , Exposición a Riesgos Ambientales/estadística & datos numéricos , Adulto , Óxidos de Nitrógeno/efectos adversos , Contaminantes Atmosféricos/efectos adversos , Modelos de Riesgos Proporcionales , Factores de Riesgo
6.
JAMA Netw Open ; 7(7): e2421665, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-39012635

RESUMEN

Importance: Psoriasis is a common autoinflammatory disease influenced by complex interactions between environmental and genetic factors. The influence of long-term air pollution exposure on psoriasis remains underexplored. Objective: To examine the association between long-term exposure to air pollution and psoriasis and the interaction between air pollution and genetic susceptibility for incident psoriasis. Design, Setting, and Participants: This prospective cohort study used data from the UK Biobank. The analysis sample included individuals who were psoriasis free at baseline and had available data on air pollution exposure. Genetic analyses were restricted to White participants. Data were analyzed between November 1 and December 10, 2023. Exposures: Exposure to nitrogen dioxide (NO2), nitrogen oxides (NOx), fine particulate matter with a diameter less than 2.5 µm (PM2.5), and particulate matter with a diameter less than 10 µm (PM10) and genetic susceptibility for psoriasis. Main Outcomes and Measures: To ascertain the association of long-term exposure to NO2, NOx, PM2.5, and PM10 with the risk of psoriasis, a Cox proportional hazards model with time-varying air pollution exposure was used. Cox models were also used to explore the potential interplay between air pollutant exposure and genetic susceptibility for the risk of psoriasis incidence. Results: A total of 474 055 individuals were included, with a mean (SD) age of 56.54 (8.09) years and 257 686 (54.36%) female participants. There were 9186 participants (1.94%) identified as Asian or Asian British, 7542 (1.59%) as Black or Black British, and 446 637 (94.22%) as White European. During a median (IQR) follow-up of 11.91 (11.21-12.59) years, 4031 incident psoriasis events were recorded. There was a positive association between the risk of psoriasis and air pollutant exposure. For every IQR increase in PM2.5, PM10, NO2, and NOx, the hazard ratios (HRs) were 1.41 (95% CI, 1.35-1.46), 1.47 (95% CI, 1.41-1.52), 1.28 (95% CI, 1.23-1.33), and 1.19 (95% CI, 1.14-1.24), respectively. When comparing individuals in the lowest exposure quartile (Q1) with those in the highest exposure quartile (Q4), the multivariate-adjusted HRs were 2.01 (95% CI, 1.83-2.20) for PM2.5, 2.21 (95% CI, 2.02-2.43) for PM10, 1.64 (95% CI, 1.49-1.80) for NO2, and 1.34 (95% CI, 1.22-1.47) for NOx. Moreover, significant interactions between air pollution and genetic predisposition for incident psoriasis were observed. In the subset of 446 637 White individuals, the findings indicated a substantial risk of psoriasis development in participants exposed to the highest quartile of air pollution levels concomitant with high genetic risk compared with those in the lowest quartile of air pollution levels with low genetic risk (PM2.5: HR, 4.11; 95% CI, 3.46-4.90; PM10: HR, 4.29; 95% CI, 3.61-5.08; NO2: HR, 2.95; 95% CI, 2.49-3.50; NOx: HR, 2.44; 95% CI, 2.08-2.87). Conclusions and Relevance: In this prospective cohort study of the association between air pollution and psoriasis, long-term exposure to air pollution was associated with increased psoriasis risk. There was an interaction between air pollution and genetic susceptibility on psoriasis risk.


Asunto(s)
Contaminación del Aire , Exposición a Riesgos Ambientales , Predisposición Genética a la Enfermedad , Material Particulado , Psoriasis , Humanos , Psoriasis/genética , Psoriasis/epidemiología , Femenino , Masculino , Contaminación del Aire/efectos adversos , Contaminación del Aire/estadística & datos numéricos , Persona de Mediana Edad , Reino Unido/epidemiología , Estudios Prospectivos , Exposición a Riesgos Ambientales/efectos adversos , Exposición a Riesgos Ambientales/estadística & datos numéricos , Material Particulado/efectos adversos , Adulto , Contaminantes Atmosféricos/efectos adversos , Anciano , Factores de Riesgo , Incidencia , Dióxido de Nitrógeno/efectos adversos , Modelos de Riesgos Proporcionales , Óxidos de Nitrógeno/efectos adversos , Óxidos de Nitrógeno/análisis
7.
Environ Sci Technol ; 58(26): 11256-11267, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38885093

RESUMEN

Short-term exposure to particles with aerodynamic diameters less than 2.5 µm (PM2.5) and ozone (O3) are important risk factors for human health. Despite the awareness of reducing attributable health burden, region-specific and source-specific strategies remain less explored due to the gap between precursor emissions and health effects. In this study, we isolate the health burden of individual sector sources of PM2.5 and O3 precursors, nitrogen oxides (NOx) and volatile organic compounds (VOCs), across the globe. Specifically, we estimate mortalities attributable to short-term exposure using machine-learning-based daily exposure estimates and quantify sectoral impacts using chemical transport model simulations. Globally, short-term exposure to PM2.5 and O3 result in 713.5 (95% Confidence Interval: 598.8-843.3) thousand and 496.3 (371.3-646.1) thousand mortalities in 2019, respectively, of which 12.5% are contributed by fuel-related NOx emissions from transportation, energy, and industry. Sectoral impacts from anthropogenic NOx and VOC emissions on health burden vary significantly among seasons and regions, requiring a target shift from transportation in winter to industry in summer for East Asia, for instance. Emission control and health management are additionally complicated by unregulated natural influences during climatic events. Fire-sourced NOx and VOC emissions, respectively, contribute to 8.5 (95% CI: 6.2-11.7) thousand and 4.8 (3.6-5.9) thousand PM2.5 and O3 mortalities, particularly for tropics with high vulnerability to climate change. Additionally, biogenic VOC emissions during heatwaves contribute to 1.8 (95% CI: 1.5-2.2) thousand O3-introduced mortalities, posing challenges in urban planning for high-income regions, where biogenic contributions to health burden during heatwaves are 13% of anthropogenic contributions annually. Our study provides important implications for temporally dynamic and sector-targeted emission control and health management strategies, which are of urgency under the projection of continuously increasing energy consumption and changing climate.


Asunto(s)
Contaminantes Atmosféricos , Ozono , Material Particulado , Humanos , Exposición a Riesgos Ambientales , Compuestos Orgánicos Volátiles , Óxidos de Nitrógeno
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 320: 124603, 2024 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-38878720

RESUMEN

Iron-sulfur cluster conversion and nitrosyl modification are involved in regulating their functions and play critical roles in signaling for biological systems. Hereby, the photo-induced dynamic process of (Me4N)2[Fe2S2(NO)4] was monitored using time-resolved electron paramagnetic resonance (EPR) spectra, MS spectra and cellular imaging methods. Photo-irradiation and the solvent affect the reaction rates and products. Spectroscopic and kinetic studies have shown that the process involves at least three intermediates: spin-trapped NO free radical species with a gav at 2.040, and two other iron nitrosyl species, dinitrosyl iron units (DNICs) and mononitrosyl iron units (MNICs) with gav values at 2.031 and 2.024, respectively. Moreover, the [Fe2S2(NO)4]2- cluster could bind with ferritin and decompose gradually, and a binding state of dinitrosyl iron coordinated with Cys102 of the recombinant human heavy chain ferritin (rHuHF) was finally formed. This study provides insight into the photodynamic mechanism of nitrosyl iron - sulfur clusters to improve the understanding of physiological activity.


Asunto(s)
Hierro , Humanos , Espectroscopía de Resonancia por Spin del Electrón , Hierro/química , Hierro/metabolismo , Óxidos de Nitrógeno/química , Óxidos de Nitrógeno/metabolismo , Unión Proteica , Cinética , Proteínas Hierro-Azufre/metabolismo , Proteínas Hierro-Azufre/química , Azufre/química , Azufre/metabolismo , Ferritinas/química , Ferritinas/metabolismo , Luz
9.
Environ Sci Technol ; 58(26): 11568-11577, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38889013

RESUMEN

Dinitrogen pentoxide (N2O5) plays an essential role in tropospheric chemistry, serving as a nocturnal reservoir of reactive nitrogen and significantly promoting nitrate formations. However, identifying key environmental drivers of N2O5 formation remains challenging using traditional statistical methods, impeding effective emission control measures to mitigate NOx-induced air pollution. Here, we adopted machine learning assisted by steady-state analysis to elucidate the driving factors of N2O5 before and during the 2022 Winter Olympics (WO) in Beijing. Higher N2O5 concentrations were observed during the WO period compared to the Pre-Winter-Olympics (Pre-WO) period. The machine learning model accurately reproduced ambient N2O5 concentrations and showed that ozone (O3), nitrogen dioxide (NO2), and relative humidity (RH) were the most important driving factors of N2O5. Compared to the Pre-WO period, the variation in trace gases (i.e., NO2 and O3) along with the reduced N2O5 uptake coefficient was the main reason for higher N2O5 levels during the WO period. By predicting N2O5 under various control scenarios of NOx and calculating the nitrate formation potential from N2O5 uptake, we found that the progressive reduction of nitrogen oxides initially increases the nitrate formation potential before further decreasing it. The threshold of NOx was approximately 13 ppbv, below which NOx reduction effectively reduced the level of night-time nitrate formations. These results demonstrate the capacity of machine learning to provide insights into understanding atmospheric nitrogen chemistry and highlight the necessity of more stringent emission control of NOx to mitigate haze pollution.


Asunto(s)
Contaminantes Atmosféricos , Atmósfera , Aprendizaje Automático , Contaminantes Atmosféricos/análisis , Atmósfera/química , Óxidos de Nitrógeno/análisis , Contaminación del Aire , Ozono/análisis , Monitoreo del Ambiente/métodos , Dióxido de Nitrógeno/análisis
10.
Environ Sci Technol ; 58(26): 11812-11821, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38897924

RESUMEN

We developed a simple strategy for preparing IrSn bimetallic clusters encapsulated in pure silicon zeolites via a one-pot hydrothermal synthesis by using diethylamine as a stabilizing agent. A series of investigations verified that metal species have been confined successfully in the inner of MFI zeolites. IrSn bimetallic cluster catalysts were efficient for the CO selective catalytic reduction of NOx in the presence of excess O2. Furthermore, the 13CO temperature-programmed surface reaction results demonstrated that NO2 and N2O could form when most of the CO was transformed into CO2 and that Sn modification could passivate CO oxidation on the IrSn bimetallic clusters, leading to more reductants that could be used for NOx reduction at high temperatures. Furthermore, SO2 can also influence the NOx conversion by inhibiting the oxidation of CO. This study provides a new strategy for preparing efficient environmental catalysts with a high dispersion of metal species.


Asunto(s)
Oxidación-Reducción , Oxígeno , Zeolitas , Zeolitas/química , Catálisis , Oxígeno/química , Monóxido de Carbono/química , Estaño/química , Óxidos de Nitrógeno/química
11.
Environ Health Perspect ; 132(6): 67010, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38922331

RESUMEN

BACKGROUND: Evidence linking gaseous air pollution to late-life brain health is mixed. OBJECTIVE: We explored associations between exposure to gaseous pollutants and brain magnetic resonance imaging (MRI) markers among Atherosclerosis Risk in Communities (ARIC) Study participants, with attention to the influence of exposure estimation method and confounding by site. METHODS: We considered data from 1,665 eligible ARIC participants recruited from four US sites in the period 1987-1989 with valid brain MRI data from Visit 5 (2011-2013). We estimated 10-y (2001-2010) mean carbon monoxide (CO), nitrogen dioxide (NO2), nitrogen oxides (NOx), and 8- and 24-h ozone (O3) concentrations at participant addresses, using multiple exposure estimation methods. We estimated site-specific associations between pollutant exposures and brain MRI outcomes (total and regional volumes; presence of microhemorrhages, infarcts, lacunes, and severe white matter hyperintensities), using adjusted linear and logistic regression models. We compared meta-analytically combined site-specific associations to analyses that did not account for site. RESULTS: Within-site exposure distributions varied across exposure estimation methods. Meta-analytic associations were generally not statistically significant regardless of exposure, outcome, or exposure estimation method; point estimates often suggested associations between higher NO2 and NOx and smaller temporal lobe, deep gray, hippocampal, frontal lobe, and Alzheimer disease signature region of interest volumes and between higher CO and smaller temporal and frontal lobe volumes. Analyses that did not account for study site more often yielded significant associations and sometimes different direction of associations. DISCUSSION: Patterns of local variation in estimated air pollution concentrations differ by estimation method. Although we did not find strong evidence supporting impact of gaseous pollutants on brain changes detectable by MRI, point estimates suggested associations between higher exposure to CO, NOx, and NO2 and smaller regional brain volumes. Analyses of air pollution and dementia-related outcomes that do not adjust for location likely underestimate uncertainty and may be susceptible to confounding bias. https://doi.org/10.1289/EHP13906.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Demencia , Exposición a Riesgos Ambientales , Imagen por Resonancia Magnética , Neuroimagen , Humanos , Contaminantes Atmosféricos/análisis , Contaminación del Aire/estadística & datos numéricos , Masculino , Femenino , Exposición a Riesgos Ambientales/estadística & datos numéricos , Demencia/epidemiología , Anciano , Persona de Mediana Edad , Óxidos de Nitrógeno/análisis , Estudios de Cohortes , Encéfalo/diagnóstico por imagen , Dióxido de Nitrógeno/análisis , Ozono/análisis , Estados Unidos/epidemiología
12.
Environ Sci Technol ; 58(26): 11781-11790, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38877971

RESUMEN

Synergistic control of nitrogen oxides (NOx) and nitrogen-containing volatile organic compounds (NVOCs) from industrial furnaces is necessary. Generally, the elimination of n-butylamine (n-B), a typical pollutant of NVOCs, requires a catalyst with sufficient redox ability. This process induces the production of nitrogen-containing byproducts (NO, NO2, N2O), leading to lower N2 selectivity of NH3 selective catalytic reduction of NOx (NH3-SCR). Here, synergistic catalytic removal of NOx and n-B via spatially separated cooperative sites was originally demonstrated. Specifically, titania nanotubes supported CuOx-CeO2 (CuCe-TiO2 NTs) catalysts with spatially separated cooperative sites were creatively developed, which showed a broader active temperature window from 180 to 340 °C, with over 90% NOx conversion, 85% n-B conversion, and 90% N2 selectivity. A synergistic effect of the Cu and Ce sites was found. The catalytic oxidation of n-B mainly occurred at the Cu sites inside the tube, which ensured the regular occurrence of the NH3-SCR reaction on the outer Ce sites under the matching temperature window. In addition, the n-B oxidation would produce abundant intermediate NH2*, which could act as an extra reductant to promote NH3-SCR. Meanwhile, NH3-SCR could simultaneously remove the possible NOx byproducts of n-B decomposition. This novel strategy of constructing cooperative sites provides a distinct pathway for promoting the synergistic removal of n-B and NOx.


Asunto(s)
Óxidos de Nitrógeno , Catálisis , Óxidos de Nitrógeno/química , Compuestos Orgánicos Volátiles/química , Oxidación-Reducción
13.
Molecules ; 29(12)2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38931005

RESUMEN

Nitroxides are stable radicals consisting of a nitroxyl group, >N-O•, which carries an unpaired electron. This group is responsible for the paramagnetic and antioxidant properties of these compounds. A recent study evaluated the effects of pyrrolidine and pyrroline derivatives of nitroxides on the antioxidant system of human red blood cells (RBCs). It showed that nitroxides caused an increase in the activity of superoxide dismutase (SOD) and the level of methemoglobin (MetHb) in cells (in pyrroline derivatives) but had no effect on the activity of catalase and lactate dehydrogenase. Nitroxides also reduced the concentration of ascorbic acid (AA) in cells but did not cause any oxidation of proteins or lipids. Interestingly, nitroxides initiated an increase in thiols in the plasma membranes and hemolysate. However, the study also revealed that nitroxides may have pro-oxidant properties. The drop in the AA concentration and the increase in the MetHb level and in SOD activity may indicate the pro-oxidant properties of nitroxides in red blood cells.


Asunto(s)
Antioxidantes , Eritrocitos , Óxidos de Nitrógeno , Superóxido Dismutasa , Humanos , Antioxidantes/farmacología , Antioxidantes/química , Ácido Ascórbico/farmacología , Ácido Ascórbico/química , Eritrocitos/metabolismo , Eritrocitos/efectos de los fármacos , Metahemoglobina/metabolismo , Óxidos de Nitrógeno/química , Oxidación-Reducción/efectos de los fármacos , Pirrolidinas/química , Pirrolidinas/farmacología , Superóxido Dismutasa/metabolismo
14.
Biochem Biophys Res Commun ; 723: 150220, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-38850811

RESUMEN

Aging is characterized as the process of functional decline in an organism from adulthood, often marked by a progressive loss of cellular function and systemic deterioration of multiple tissues. Among the numerous molecular, cellular, and systemic hallmarks associated with aging, mitochondrial dysfunction is considered one of the pivotal factors that initiates the aging process. During aging, mitochondria undergo varying degrees of damage, resulting in impaired energy production and disruption of the homeostatic regulation of mitochondrial quality control systems, which in turn affects cellular energy metabolism and results in cellular dysfunction, accelerating the aging process. AMP-activated protein kinase (AMPK) and the mechanistic target of rapamycin complex 1 (mTORC1) are two central kinase complexes responsible for sensing intracellular nutrient levels, regulating metabolic homeostasis, modulating aging and play a crucial role in maintaining the homeostatic balance of mitochondria. Our previous studies found that the novel compound tetramethylpyrazine nitrone (TBN) can protect mitochondria via the AMPK/mTOR pathway in many animal models, extending healthy lifespan through the Nrf2 signaling pathway in nematodes. Building upon this foundation, we have posited a reasonable hypothesis, TBN can improve mitochondrial function to delay aging by regulating the AMPK/mTORC1 signaling pathway. This study focuses on the C. elegans, exploring the impact and underlying mechanisms of TBN on aging and mitochondrial function (especially the mitochondrial quality control system) during the aging process. The present studies demonstrated that TBN extends lifespan of wild-type nematodes and is associated with the AMPK/mTORC1 signaling pathway. TBN elevated ATP and NAD+ levels in aging nematodes while orchestrating mitochondrial biogenesis and mitophagy. Moreover, TBN was observed to significantly enhance normal activities during aging in C. elegans, such as mobility and pharyngeal pumping, concurrently impeding lipofuscin accumulation that were closely associated with AMPK and mTORC1. This study not only highlights the delayed effects of TBN on aging but also underscores its potential application in strategies aimed at improving mitochondrial function via the AMPK/mTOR pathway in C. elegans.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Envejecimiento , Caenorhabditis elegans , Diana Mecanicista del Complejo 1 de la Rapamicina , Mitocondrias , Pirazinas , Transducción de Señal , Animales , Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/efectos de los fármacos , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Pirazinas/farmacología , Mitocondrias/metabolismo , Mitocondrias/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Proteínas Quinasas Activadas por AMP/metabolismo , Envejecimiento/metabolismo , Envejecimiento/efectos de los fármacos , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Óxidos de Nitrógeno/metabolismo
15.
Int J Mol Sci ; 25(12)2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38928220

RESUMEN

We hypothesize that the injection of JP4-039, a mitochondria-targeted nitroxide, prior to irradiation of the mouse retina may decrease apoptosis and reduce neutrophil and macrophage migration into the retina. In our study, we aimed to examine the effects of JP4-039 in the mouse retina using fluorescent microscopy, a terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, and flow cytometry. Forty-five mice and one eye per mouse were used. In Group 1, fluorescent microscopy was used to determine retinal uptake of 10 µL (0.004 mg/µL) of intravitreally injected BODIPY-labeled JP4-039 at 0, 15, and 60 min after injection. In Group 2, the TUNEL assay was performed to investigate the rate of apoptosis after irradiation in addition to JP4-039 injection, compared to controls. In Group 3, flow cytometry was used to determine the extent of inflammatory cell migration into the retina after irradiation in addition to JP4-039 injection, compared to controls. Maximal retinal uptake of JP4-039 was 15 min after intravitreal injection (p < 0.0001). JP4-039-treated eyes had lower levels of retinal apoptosis (35.8 ± 2.5%) than irradiated controls (49.0 ± 2.7%; p = 0.0066) and demonstrated reduced migration of N1 cells (30.7 ± 11.7% vs. 77.7 ± 5.3% controls; p = 0.004) and M1 cells (76.6 ± 4.2 vs. 88.1 ± 3.7% controls, p = 0.04). Pretreatment with intravitreally injected JP4-039 reduced apoptosis and inflammatory cell migration in the irradiated mouse retina, marking the first confirmed effect of this molecule in retinal tissue. Further studies may allow for safety profiling and potential use for patients with radiation retinopathy.


Asunto(s)
Apoptosis , Movimiento Celular , Mitocondrias , Retina , Animales , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Ratones , Retina/efectos de los fármacos , Retina/metabolismo , Retina/efectos de la radiación , Retina/patología , Mitocondrias/metabolismo , Mitocondrias/efectos de los fármacos , Mitocondrias/efectos de la radiación , Movimiento Celular/efectos de los fármacos , Movimiento Celular/efectos de la radiación , Ratones Endogámicos C57BL , Masculino , Óxidos de Nitrógeno/farmacología , Inflamación/patología
16.
Glob Chang Biol ; 30(6): e17368, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38847421

RESUMEN

Nitrogen oxides (NOx) play an important role for atmospheric chemistry and radiative forcing. However, NOx emissions from the vast northern circumpolar permafrost regions have not been studied in situ due to limitations of measurement techniques. Our goals were to validate the offline analytical technique, and based on this, to widely quantify in situ NOx emissions from peatlands in the southern Eurasian permafrost region. To this end, we conducted a comparison of online and offline flux measurements in 2018 and 2019 using the synthetic air flushing, steady-state opaque chamber method. With differences in annual average and cumulative fluxes less than 0.1 µg N m-2 h-1 and 0.01 kg N ha-1 year-1, the online and offline fluxes were in good agreement, demonstrating the feasibility of conducting offline measurements in remote regions without power supply. The flux measurements over 2 years showed obvious NOx emissions of 0.05-0.14 and 0.13-0.30 kg N ha-1 year-1 in the hollow and hummock microtopography of permafrost peatlands, respectively. The rapid expansion of alder (Alnus sibirica) in the peatlands induced by permafrost degradation significantly increased soil mineral N contents and NOx emissions depending on the age of alder (0.64-1.74 and 1.44-2.20 kg N ha-1 year-1 from the alder forests with tree ages of 1-10 years and 11-20 years, respectively). Alder expansion also intensively altered the thermal state of permafrost including the sharp increases of soil temperatures during the non-growing season from October to April and active layer thickness. This study provides the first in situ evidences of NOx emissions from the northern circumpolar permafrost regions and uncovers the well-documented expansion of alders can substantially stimulate NOx emissions and thus, significantly affect air quality, radiative forcing, and ecosystem productivity in the pristine regions.


Asunto(s)
Óxidos de Nitrógeno , Hielos Perennes , Suelo , Suelo/química , Óxidos de Nitrógeno/análisis , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente
17.
Front Public Health ; 12: 1394678, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38855452

RESUMEN

Introduction: Many decarbonization technologies have the added co-benefit of reducing short-lived climate pollutants, such as particulate matter (PM), nitrogen oxides (NOx), and sulfur dioxide (SO2), creating a unique opportunity for identifying strategies that promote both climate change solutions and opportunities for air quality improvement. However, stakeholders and decision-makers may struggle to quantify how these co-benefits will impact public health for the communities most affected by industrial air pollution. Methods: To address this problem, the LOCal Air Emissions Tracking Atlas (LOCAETA) fills a data availability and analysis gap by providing estimated air quality benefits from industrial decarbonization options, such as carbon capture and storage (CCS). These co-benefits are calculated using an algorithm that connects disparate datasets that separately report greenhouse gas emissions and other pollutants at U.S. industrial facilities. Results: Version 1.0 of LOCAETA displays the estimated primary PM2.5 emission reduction co-benefits from additional pretreatment equipment for CCS on industrial and power facilities across the state of Louisiana, as well as the potential for VOC and NH3 generation. The emission reductions are presented in the tool alongside facility pollutant emissions information and relevant air quality, environmental, demographic, and public health datasets, such as air toxics cancer risk, satellite and in situ pollutant measurements, and population vulnerability metrics. Discussion: LOCAETA enables regulators, policymakers, environmental justice communities, and industrial and commercial users to compare and contrast quantifiable public health benefits due to air quality impacts from various climate change mitigation strategies using a free and publicly-available tool. Additional pollutant reductions can be calculated using the same methodology and will be available in future versions of the tool.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Monitoreo del Ambiente , Material Particulado , Contaminación del Aire/análisis , Contaminantes Atmosféricos/análisis , Material Particulado/análisis , Humanos , Louisiana , Industrias , Dióxido de Azufre/análisis , Cambio Climático , Óxidos de Nitrógeno/análisis
18.
Sci Total Environ ; 944: 173777, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-38844213

RESUMEN

BACKGROUND: The association between exposure to air pollutants and cardiovascular disease (CVD) trajectory in individuals with circadian syndrome remains inconclusive. METHODS: The individual exposure levels of air pollutants, including particulate matter (PM) with aerodynamic diameter ≤ 2.5 µm (PM2.5), PM with aerodynamic diameter ≤ 10 µm (PM10), PM2.5 absorbance, PM with aerodynamic diameter between 2.5 µm and 10 µm, nitrogen dioxide (NO2), nitrogen oxides (NOx), and air pollution score (overall air pollutants exposure), were estimated for 48,850 participants with circadian syndrome from the UK Biobank. Multistate regression models were employed to estimate associations between exposure to air pollutants and trajectories from circadian syndrome to CVD/CVD subtypes (including coronary heart disease [CHD], atrial fibrillation [AF], heart failure [HF], and stroke) and death. Mediation roles of CVD/CVD subtypes in the associations between air pollutants and death were evaluated. RESULTS: After a mean follow-up time over 12 years, 12,570 cases of CVD occurred, including 8192 CHD, 1693 AF, 1085 HF, and 1600 stroke cases. In multistate model, per-interquartile range increment in PM2.5 (hazard ratio: 1.08; 95 % confidence interval: 1.06, 1.10), PM10 (1.04; 1.01, 1.06), PM2.5 absorbance (1.04; 1.02, 1.06), NO2 (1.07; 1.03, 1.11), NOx (1.08; 1.04, 1.12), or air pollution score (1.06; 1.03, 1.08) was associated with trajectory from circadian syndrome to CVD. Significant associations between the above-mentioned air pollutants and trajectories from circadian syndrome and CVD to death were observed. CVD, particularly CHD, significantly mediated the associations of PM2.5, NO2, NOx, and air pollution score with death. CONCLUSIONS: Long-term exposure to air pollutants during circadian syndrome was associated with subsequent CVD and death. CHD emerged as the most prominent CVD subtype in CVD progression driven by exposure to air pollutants during circadian syndrome. Our study highlights the importance of controlling air pollutants exposure and preventing CHD in people with circadian syndrome.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Enfermedades Cardiovasculares , Exposición a Riesgos Ambientales , Material Particulado , Humanos , Contaminantes Atmosféricos/análisis , Enfermedades Cardiovasculares/mortalidad , Material Particulado/análisis , Exposición a Riesgos Ambientales/estadística & datos numéricos , Masculino , Contaminación del Aire/estadística & datos numéricos , Femenino , Persona de Mediana Edad , Trastornos Cronobiológicos , Anciano , Adulto , Óxidos de Nitrógeno/análisis , Reino Unido/epidemiología , Dióxido de Nitrógeno/análisis
19.
Int J Mol Sci ; 25(11)2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38892102

RESUMEN

The synthesis, antioxidant capacity, and anti-inflammatory activity of four novel N-benzyl-2-[4-(aryl)-1H-1,2,3-triazol-1-yl]ethan-1-imine oxides 10a-d are reported herein. The nitrones 10a-d were tested for their antioxidant properties and their ability to inhibit soybean lipoxygenase (LOX). Four diverse antioxidant tests were used for in vitro antioxidant assays, namely, interaction with the stable free radical DPPH (1,1-diphenyl-2-picrylhydrazyl radical) as well as with the water-soluble azo compound AAPH (2,2'-azobis(2-amidinopropane) dihydrochloride), competition with DMSO for hydroxyl radicals, and the scavenging of cationic radical ABTS•+ (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) radical cation). Nitrones 10b, 10c, and 10d, having the 4-fluorophenyl, 2,4-difluorophenyl, and 4-fluoro-3-methylphenyl motif, respectively, exhibited high interaction with DPPH (64.5-81% after 20 min; 79-96% after 60 min), whereas nitrone 10a with unfunctionalized phenyl group showed the lowest inhibitory potency (57% after 20 min, 78% after 60 min). Nitrones 10a and 10d, decorated with phenyl and 4-fluoro-3-methylphenyl motif, respectively, appeared the most potent inhibitors of lipid peroxidation. The results obtained from radical cation ABTS•+ were not significant, since all tested compounds 10a-d showed negligible activity (8-46%), much lower than Trolox (91%). Nitrone 10c, bearing the 2,4-difluorophenyl motif, was found to be the most potent LOX inhibitor (IC50 = 10 µM).


Asunto(s)
Antioxidantes , Antioxidantes/farmacología , Antioxidantes/química , Antioxidantes/síntesis química , Lipooxigenasa/metabolismo , Glycine max/enzimología , Glycine max/química , Inhibidores de la Lipooxigenasa/farmacología , Inhibidores de la Lipooxigenasa/química , Inhibidores de la Lipooxigenasa/síntesis química , Triazoles/química , Triazoles/farmacología , Triazoles/síntesis química , Iminas/química , Iminas/farmacología , Compuestos de Bifenilo/química , Compuestos de Bifenilo/antagonistas & inhibidores , Picratos/química , Picratos/antagonistas & inhibidores , Óxidos de Nitrógeno/química , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/farmacología , Depuradores de Radicales Libres/síntesis química
20.
Environ Sci Technol ; 58(23): 10388-10397, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38828512

RESUMEN

Selective catalytic reduction of nitrogen oxides (NOx) with ammonia (NH3-SCR) is an efficient NOx reduction strategy, while the denitrification (deNOx) catalysts suffer from serious deactivation due to the coexistence of multiple poisoning substances, such as alkali metal (e.g., K), SO2, etc., in industrial flue gases. It is essential to understand the interaction among various poisons and their effects on the deNOx process. Herein, the ZSM-5 zeolite-confined MnSmOx mixed (MnSmOx@ZSM-5) catalyst exhibited better deNOx performance after the poisoning of K, SO2, and/or K&SO2 than the MnSmOx and MnSmOx/ZSM-5 catalysts, the deNOx activity of which at high temperature (H-T) increased significantly (>90% NOx conversion in the range of 220-480 °C). It has been demonstrated that K would occupy both redox and acidic sites, which severely reduced the reactivity of MnSmOx/ZSM-5 catalysts. The most important, K element is preferentially deposited at -OH on the surface of ZSM-5 carrier due to the electrostatic attraction (-O-K). As for the K&SO2 poisoning catalyst, SO2 preferred to be combined with the surface-deposited K (-O-K-SO2ads) according to XPS and density functional theory (DFT) results, the poisoned active sites by K would be released. The K migration behavior was induced by SO2 over K-poisoned MnSmOx@ZSM-5 catalysts, and the balance of surface redox and acidic site was regulated, like a synergistic promoter, which led to K-poisoning buffering and activity recovery. This work contributes to the understanding of the self-detoxification interaction between alkali metals (e.g., K) and SO2 on deNOx catalysts and provides a novel strategy for the adaptive use of one poisoning substance to counter another for practical NOx reduction.


Asunto(s)
Zeolitas , Zeolitas/química , Catálisis , Oxidación-Reducción , Óxidos de Nitrógeno/química , Óxidos/química , Amoníaco/química , Desnitrificación , Metales/química
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