Ce6/PTX₂‑NP/G@NHs Confer Radiosensitivity in Non-Small Cell Lung Cancer <i>via</i> Promotion of Apoptotic Body-Mediated Neighboring Effects

This study fabricates a nanoparticle delivery system of gold nanoparticles–dextran nanoparticles loaded with hypoxia-activated paclitaxel dimeric prodrug nanoparticles (PTX2-NP) and photosensitizer chlorin e6/paclitaxel-nanoparticle/gold@N-(2-hydroxypropyl) (Ce6/PTX2-NP/G@NHs) and analyzed the possible molecular mechanism for enhancing the radiosensitivity of non-small cell lung cancer (NSCLC). Ce6/PTX2-NP/G@NHs were prepared by a coupling reaction and dextran inclusion, followed by characterization using spectroscopy techniques. The cellular uptake and cytotoxicity of Ce6/PTX2-NP/G@NHs were analyzed. Radiosensitizing effects of the nanoparticles were evaluated by determining the malignant phenotypes and reactive oxygen species production of A549 cells and PI3K/AKT pathway-related proteins under 685 nm laser irradiation. A549 tumor-bearing nude mice were modeled to further confirm the radiosensitizing effect. Ce6/PTX2-NP/G@NHs were effectively internalized by A549 cells, producing cytotoxicity under laser irradiation. Ce6/PTX2-NP/G@NHs reduced cell viability, clonogenic potential, migration, and invasion along with reactive oxygen species (ROS) production while promoting apoptosis in A549 cells under laser irradiation. By inhibiting the PI3K/AKT pathway, Ce6/PTX2-NP/G@NHs increased the sensitivity of A549 cells to radiotherapy where apoptotic body (ApoBD)-mediated neighboring effects also played a key role. Ce6/PTX2-NP/G@NHs accumulated in tumor sites of nude mice and enhanced the radiosensitivity of NSCLC. Ce6/PTX2-NP/G@NHs showed no obvious toxicity or side effects in vivo. Collectively, the new Ce6/PTX2-NP/G@NHs nanoparticle delivery system can enhance the radiosensitivity of NSCLC via the promotion of ApoBD-mediated neighboring effects and inactivation of the PI3K/AKT pathway

Evaluating urban and nonurban PM_2.5 variability under clean air actions in China during 2010–2022 based on a new high-quality dataset

The air quality in China has changed due to the implementation of clean air actions since 2013. Evaluating the spatial pattern of PM2.5 and the effectiveness of reducing anthropogenic emissions in urban and nonurban areas is crucial. Therefore, the China Long-term Air Pollutant dataset for PM2.5 (CLAP_PM2.5) was generated from 2010 to 2022 with a daily 0.1° resolution using the random forest model and integrating multiple data sources, including extensive in-situ PM2.5 measurements, visibility, satellite retrievals, surface and upper-level meteorological data and other ancillary data. The CLAP_PM2.5 dataset is more reliable and accurate than other public datasets. Analysis of CLAP_PM2.5 from 2010 to 2022 reveals the decrease in positive urban-nonurban PM2.5 differences and higher decreasing rates of PM2.5 in most city clusters in eastern China. Furthermore, separating meteorological and emission contributions to the PM2.5 variability by a meteorological normalization approach indicates that meteorological contribution gradually changed from unfavorable to PM2.5 reduction during 2013–2017 to favorable to decline enhancement during 2018–2022, and in urban regions, meteorological contribution is higher than that in nonurban areas. Overall, the reduction in deweathered PM2.5 concentrations highlights China's significant achievements in terms of comprehensive clean air actions.</p