Design, synthesis, and biological evaluation of 2-arylamino-4-(piperidin-4-yloxy)pyrimidines as potent EGFRT790M/L858R inhibitors to treat non-small cell lung cancer.

Three types of 2-arylamino-4-(piperidin-4-yloxy)pyrimidines (I-III) were designed and synthesized as covalent EGFR(epidermal growth factor receptor)T790M/L858R inhibitors by replacement of the common reported 4-(3-amino)phenoxyl moiety with 4-(4-hydroxy)piperidine-4-oxyl, and the introduction of fused-thiophene or -pyrrole on the pyrimidine core to strategically achieve conformational restriction. According to our biological evaluation, it was found that compound 9i could potently suppress EGFRT790M/L858R kinase and H1975 cell proliferation, with IC50 values of 4.902 nM and 0.6210 µM, respectively. Further study showed that 9i not only demonstrated highly selective inhibitory effects toward EGFRT790M/L858R over wild-type EGFR (EGFRWT), but it also had low cytotoxicity against normal HBE(human bronchial epithelial) and L-02 cells. Action mechanism studies showed that 9i effectively hindered cell migration and promoted apoptosis by AO(Acridine Orange)/EB(Ethidium Bromide) staining. These data would provide important clues for the screening of novel covalent EGFRT790M/L858R inhibitors for non-small cell lung cancer (NSCLC) treatment.

Uptake of polycyclic aromatic hydrocarbons (PAHs) from PAH-contaminated soils to carrots and Chinese cabbages under the greenhouse and field conditions.

Polycyclic aromatic hydrocarbons (PAHs) with the properties of structural stability, semi-volatility, and hydrophobicity are toxic and persistent in environments; thus, their transport and fate in agroecosystems is essential for reducing PAH accumulation in the edible parts of crops. Here, we cultivated cabbages (Brassica pekinensis L.) and carrots (Daucus carota L.) in PAH-contaminated soils under the greenhouse and field conditions. After harvesting, we observed a 9.5-46% reduction in soil ∑PAH concentrations. There were 37% of bioconcentration factors (BCFbs) > 1 and 93% of translocation factors (TFab) > 1, while low-molecular-weight (LMW) PAHs had higher BCFbs than high-molecular-weight (HMW) PAHs. The PAH concentrations showed significant and positive correlations among soils, the belowground parts, and the aboveground parts. The toxicity equivalent concentration (TEQBaP) followed the order of cabbage (greenhouse) > cabbage (field) > carrot (greenhouse) > carrot (field), suggesting potentially higher health risks in cabbage relative to carrot and vegetables under the greenhouse relative to field condition. Our study suggested growing carrots under field conditions as a management strategy for reducing the risks of vegetables grown in PAH-contaminated soils.

Effects of autumn diurnal freeze-thaw cycles on soil bacteria and greenhouse gases in the permafrost regions.

Understanding the impacts of diurnal freeze-thaw cycles (DFTCs) on soil microorganisms and greenhouse gas emissions is crucial for assessing soil carbon and nitrogen cycles in the alpine ecosystems. However, relevant studies in the permafrost regions in the Qinghai-Tibet Plateau (QTP) are still lacking. In this study, we used high-throughput pyrosequencing and static chamber-gas chromatogram to study the changes in topsoil bacteria and fluxes of greenhouse gases, including carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O), during autumn DFTCs in the permafrost regions of the Shule River headwaters on the western part of Qilian Mountains, northeast margin of the QTP. The results showed that the bacterial communities contained a total of 35 phyla, 88 classes, 128 orders, 153 families, 176 genera, and 113 species. The dominant phyla were Proteobacteria, Acidobacteria, Actinobacteria, Chloroflexi, and Gemmatimonadetes. Two DFTCs led to a trend of increasing bacterial diversity and significant changes in the relative abundance of 17 known bacteria at the family, genus, and species levels. These were predominantly influenced by soil temperature, water content, and salinity. In addition, CO2 flux significantly increased while CH4 flux distinctly decreased, and N2O flux tended to increase after two DFTCs, with soil bacteria being the primary affecting variable. This study can provide a scientific insight into the impact of climate change on biogeochemical cycles of the QTP.