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N6‐methyladenosine (m6A) is the most prevalent internal RNA modification in mammals. However, limited research has been conducted on the role of m6A in coronary artery disease (CAD). We conducted methylated RNA immunoprecipitation sequencing and RNA sequencing to obtain a genome‐wide profile of m6A‐modified long noncoding RNAs (lncRNAs) in human coronary artery smooth muscle cells either exposed to oxidized low‐density lipoprotein treatment or not, and the characteristics of the expression profiles were explored using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses. The predictive effects of seven selected lncRNAs on CAD were evaluated in peripheral blood mononuclear cells (PBMCs). The differentially m6A‐modified and expressed lncRNAs related genes were predominantly enriched in small GTPase‐mediated signal transduction, ErbB signaling, and Rap1 signaling. Additionally, the expression levels of uc003pes.1, ENST00000422847, and NR_110155 were significantly associated with CAD, with uc003pes.1 identified as an independent risk factor and NR_110155 as an independent protective factor for CAD. NR_110155 and uc003pes.1 in PBMCs have the potential to serve as biomarkers for predicting CAD. [ABSTRACT FROM AUTHOR]

The growth of newly formed particles through new particle formation (NPF) contributes a significant fraction to the cloud condensation nuclei, yet the driving mechanisms remain unclear, especially for polluted environments. To investigate the potential species contributing for nanoparticle growth in environments with significant anthropogenic influences, we measured the hygroscopicity of newly formed particles at 20–40 nm at a rural observational site in the North China Plain during winter 2018. Our results demonstrate that these particles were not very hygroscopic, with the mean hygroscopicity parameter κ of 0.13 ± 0.09. Clear differences in the inferred κ of the growing material responsible for the growth were observed among different events, indicating that even at the same region, the compounds driving particle growth may not be identical. This may be synergistically influenced by the NPF precursors, oxidants and meteorological conditions, suggesting complex mechanisms might co‐exist behind nanoparticle growth in polluted environments. Plain Language Summary: Particles newly formed through nucleation grow large enough to become cloud condensation nuclei which influences climate. However, the driving mechanisms and the key contributing species for nanoparticle growth are poorly understood. Here, we present direct measurements of the hygroscopicity of particles through new particle formation (NPF) that occurred in a rural environment in the North China Plain (NCP) during wintertime of 2018. Relatively low hygroscopicity of these newly formed particles were observed, suggesting less water‐soluble compounds drove the growth there. We also found that the hygroscopicity of the growing material responsible for nanoparticle growth was not identical on different NPF days. Our results reveal that the compounds driving the growth varied with different NPF conditions, deepening our understanding of nanoparticle growth in polluted environments. Key Points: Particles with sizes at 20–40 nm formed through new particle formation (NPF) are not very hygroscopic at rural North China Plain (NCP)The hygroscopicity parameter κ of the growing material varied from ∼0 to ∼0.1 among NPF eventsPrecursors, oxidants and meteorological conditions may synergistically determine the chemical compounds responsible for particle growth [ABSTRACT FROM AUTHOR]

A significant decrease in surface PM2.5 concentrations has been reported since the implementation of the Air Pollution Prevention and Control Action Plan in 2013. In this study, we use the GEOS-Chem model to simulate the trend in surface PM2.5 pollution in China from 2013 to 2017, as well as the relative contributions of emission reduction and meteorology. The simulated decline rate averaged over monitoring sites in China is around −4.7 μg m−3 yr−1 in comparison with the value of −6.4 μg m−3 yr−1 from observations. The model also captures the variations over different regions, with r in the range of 0.85–0.95. Based on the sensitivity tests against emissions and meteorology, the study finds that the decline in PM2.5 concentrations is mainly driven by the reduction in anthropogenic emissions. The variation in open biomass burning (OBB) is not significant, except in Northeast China (NEC) and Pearl River Delta (PRD), where the changes originated from OBB are 40% and 30% of those associated with anthropogenic emission reductions. Changes in meteorology from 2013 to 2017 led to significant increases in PM2.5 concentrations in most areas in China, except in NEC. The increase attributed to meteorology, to a large extent, could be explained by the significant decrease in surface wind speed (WS) and planetary boundary layer height (PBLH) between 2013 and 2017, combined with their negative correlation with PM2.5. The decrease in PM2.5 concentrations in NEC, on the other hand, could be explained by the significant decrease in relative humidity (RH) there combined with the positive correlation of RH with PM2.5, while the changes in WS and PBLH there are relatively small compared with other areas. The change in meteorology, therefore, hinders the improvement of air quality via emission controls in most of China. In Sichuan Basin (SCB), the increase due to meteorology almost compensates for the decrease associated with emission reduction, leading to the least change in PM2.5 concentrations, although the decrease due to emission controls is the largest compared with other areas. [ABSTRACT FROM AUTHOR]

Objective: To investigate the therapeutic effect and mechanism of sivelestat sodium on acute lung injury (AIL). Methods: A rat model for ALI/acute respiratory distress syndrome (ALI/ARDS) was established. Pathological examination of lung tissue was conducted to assess lung injury. Blood gas in the arteries was measured using a blood analyzer. Changes in PaO2, PaO2/FiO2, and lung wet/dry (W/D) weight ratio were carefully compared. ELISA assay was conducted to estimate cell adhesion and inflammation response. Finally, real-time reverse transcription polymerase chain reaction and western blotting assay was used to determine the activation of PI3K/AKT/mTOR pathway. Results: ARDS in vivo model was successfully constructed by LPS injection. Compared with the sham group, PaO2 and PaO2/FiO2 were significantly lower in the vehicle group, while the lung W/D ratio, the lung injury score, NE, VCAM-1, IL-8 andTNF-αwere significantly increased. After treatment with different doses of sivelestat sodium, we found PaO2, PaO2/FiO2 were prominently increased, while the lung W/D ratio, the lung injury score, NE, VCAM-1, IL-8, TNF-α levels were decreased in the dose-dependent manner. Meanwhile, compared with the vehicle group, the expression levels of Bax, PI3K, Akt and mTOR were significantly lower, and the expression of Bcl-2 was significantly higher after injection with sivelestat sodium. Conclusion: Sivelestat sodium has an interventional effect on ALI in sepsis by inhibiting the PI3K/AKT/mTOR signalling pathway. [ABSTRACT FROM AUTHOR]

Current process-based research mainly uses box models to evaluate photochemical ozone production and destruction rates, and it is unclear to what extent the photochemical reaction mechanisms are elucidated. Here, we modified and improved a net photochemical ozone production rate (NPOPR, P (O 3) net) detection system based on the current dual-channel reaction chamber technique, which makes the instrument applicable to different ambient environments, and its various operating indicators were characterized, i.e., "airtightness", light transmittance, wall losses of the reaction and reference chambers, conversion rate of O 3 to NO 2 , air residence time, and performance of the reaction and reference chambers. The limits of detection of the NPOPR detection system were determined to be 0.07, 1.4, and 2.3 ppbv h -1 at sampling flow rates of 1.3, 3, and 5 L min -1 , respectively. We further applied the NPOPR detection system to field observations at an urban site in the Pearl River Delta (China). During the observation period, the maximum value of P (O 3) net was 34.1 ppbv h -1 , which was ∼ 0 ppbv h -1 at night within the system detection error and peaked at approximately noon local time. The daytime (from 06:00–18:00 LT) average value of P (O 3) net was 12.8 (± 5.5) ppbv h -1. We investigated the detailed photochemical O 3 formation mechanism in the reaction and reference chambers of the NPOPR detection system using a zero-dimensional box model. We found that the photochemical reactions in the reaction chamber were very close to those in ambient air, but there was not zero chemistry in the reference chamber because the reaction related to the production and destruction of RO 2 (= HO 2 + RO 2) continued in the reference chamber, which led to a small amount of P (O 3) net. Therefore, the P (O 3) net measured here can be regarded as the lower limit of the real P (O 3) net in the atmosphere; however, the measured P (O 3) net was still ∼ 7.5 to 9.3 ppbv h -1 higher than the modeled P (O 3) net value depending on different modeling methods, which may be due to the inaccurate estimation of HO 2 / RO 2 radicals in the modeling study. Short-lived intermediate measurements coupled with direct P (O 3) net measurements are needed in the future to better understand O 3 photochemistry. Our results show that the NPOPR detection system can achieve high temporal resolution and continuous field observations, which helps us to better understand photochemical O 3 formation and provides a key scientific basis for continuous improvement of air quality in China. [ABSTRACT FROM AUTHOR]