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Three pairs of enantiomers and one achiral molecule that are new ethylated derivatives of sulfur and nitrogen-containing compounds named mantidisamides E–H (1–4), along with twenty known ones (5–24), were derived from the ethanol extract of Tenodera sinensis Saussure. The structures of these new compounds and their absolute configurations were assigned on the basis of spectroscopic analyses and computational methods. The assessment of activities in NRK-52e cells induced by TGF-β1 demonstrated that the previously undescribed compounds 1 and 2 exhibited a significant capacity to inhibit the expression of proteins (fibronectin, collagen I, and α-SMA). Moreover, the biological activity of these compounds was found to increase with rising concentrations. Notably, compounds 1–4 should be artifacts; however, undescribed compounds 1 and 2, which possessed obvious biological activity, might be attractive for chemists and biologists due to the potential for more detailed exploration of their properties. It is worth mentioning that compounds 1 and 2 remain novel structures even in the absence of the ethoxy group. [ABSTRACT FROM AUTHOR]

The hot deformation behavior of Cr-Mo-B mechanical engineering steel was conducted at deformation temperature of 850-1150℃ and strain rates of 0.1-10s-1. The artificial neural network(ANN) model was developed based on the true stress-strain curves, where the input parameters were deformation temperature, strain rate, strain, and flow stress was the output parameter. The results show that the ANN model is accurate in predicting the flow stress, and the root mean square error is 1.3858. Based on the dynamic material model (DMM), the processing maps of the studied alloy at true strains of 0.5 and 0.7 are constructed to recognize optimum hot deformation regions:the optimum region for the strain of 0.5 is at deformation temperature of 1050-1150℃ and strain rate of 0.1-0.4s-1 with a peak power dissipation factor of about 37.20%, and the optimum region for the strain of 0.7 is at deformation temperature of 1000-1150℃ and strain rate of 0.1-0.6s-1 with a peak power dissipation factor of about 35.80%.

Background and Purpose: The mammalian target of rapamycin (mTOR) pathway plays critical roles in intrinsic chemoresistance by regulating Fanconi anaemia complementation group D2 (FANCD2) expression. However, the mechanisms by which mTOR regulates FANCD2 expression and related inhibitors are not clearly elucidated. Extracts of Centipeda minima (C. minima) showed promising chemosensitizing effects by inhibiting FANCD2 activity. Here, we have aimed to identify the bioactive chemosensitizer in C. minima extracts and elucidate its underlying mechanism. Experimental Approach: The chemosensitizing effects of arnicolide C (ArC), a bioactive compound in C. minima, on non‐small cell lung cancer (NSCLC) were investigated using immunoblotting, immunofluorescence, flow cytometry, the comet assay, small interfering RNA (siRNA) transfection and animal models. The online SynergyFinder software was used to determine the synergistic effects of ArC and chemotherapeutic drugs on NSCLC cells. Key Results: ArC had synergistic cytotoxic effects with DNA cross‐linking drugs such as cisplatin and mitomycin C in NSCLC cells. ArC treatment markedly decreased FANCD2 expression in NSCLC cells, thus attenuating cisplatin‐induced FANCD2 nuclear foci formation, leading to DNA damage and apoptosis. ArC inhibited the mTOR pathway and attenuated mTOR‐mediated expression of E2F1, a critical transcription factor of FANCD2. Co‐administration of ArC and cisplatin exerted synergistic anticancer effects in the A549 xenograft mouse model by suppressing mTOR/FANCD2 signalling in tumour tissues. Conclusion and Implications: ArC suppressed DNA cross‐linking drug‐induced DNA damage response by inhibiting the mTOR/E2F1/FANCD2 signalling axis, serving as a chemosensitizing agent. This provides insight into the anticancer mechanisms of ArC and offers a potential combinatorial anticancer therapeutic strategy. [ABSTRACT FROM AUTHOR]

Investigation on the chemical components of Valeriana jatamansi Jones (Caprifoliaceae), a new lignan with pyran-ring, dipsalignan G (1), along with eight known compounds (2–9) were isolated. Their structures were elucidated by extensive analysis of 1D, 2D NMR and HR-ESI-MS spectroscopic data. Additionally, possible biosynthetic pathway of 1 was proposed. Finally, biological evaluation results showed that 8 had significant scavenging ability to ABTS and DPPH free radicals, with IC50 values of 1.35 ± 0.01 and 2.94 ± 0.01 μg/ml, respectively. [ABSTRACT FROM AUTHOR]