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Yong Zhong, Chuntao Li, Yaling Xiang, Jinbiao Zhou, Jianqing Zhang Department of Respiratory and Critical Care Medicine, the First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, People’s Republic of ChinaCorrespondence: Jianqing Zhang, Department of Respiratory Critical Care Medicine, the First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, 650032, People’s Republic of China, Tel +86 18988272502, Email ydyyzjq@163.comObjective: LncRNAs are closely correlated with chronic obstructive pulmonary disease (COPD). We investigated the molecular mechanism of lncRNA RP11-521C20.3, which targets the action of the Bcl-2 modifying factor (BMF) signaling pathway in the apoptosis of cigarette smoke extract (CSE)-treated A549 cells.Methods: Lung tissues derived from cigarette smoke exposed rats (COPD group) and controls were examined using TUNEL assay for apoptotic cells and using immunohistochemistry for BMF expression levels. Overexpression and knockdown of BMF by lentiviral vector transfection were used to explore the role of BMF on the apoptosis of CSE-treated A549 cells. Overexpression and knockdown of RP11-521C20.3 were used to assess the effect of RP11-521C20.3 on the expression levels of BMF and apoptosis in CSE-treated A549 cells. Cell proliferation, mitochondrial morphology, and apoptosis were assessed in A549 cells. Real-time quantitative polymerase chain reactions and Western blotting detected the expression of apoptosis-related molecules.Results: The number of apoptotic cells and the level of BMF protein were significantly increased in lung tissues of the COPD group compared to the control group. Overexpression of BMF or knockdown of RP11-521C20.3 in CSE-treated A549 cells increased apoptosis, inhibited cell proliferation, and exacerbated mitochondrial damage. There were also increased protein levels of p53, cleaved caspase-3, and cleaved caspase-7, and decreased protein levels of Bcl-2 and survivin. Knockdown of BMF or overexpression of RP11-521C20.3 in CSE-treated A549 cells attenuated apoptosis, promoted cell proliferation, and alleviated mitochondrial damage. Observed effects also included decreased protein levels of p53, cleaved caspase-3, and cleaved caspase-7, and increased protein levels of Bcl-2 and survivin. In CSE-treated A549 cells, overexpression of RP11-521C20.3 suppressed the expression of BMF mRNA and protein.Conclusion: In CSE-treated A549 cells, BMF promoted apoptosis and RP11-521C20.3 might target the BMF signaling axis to protect CSE-treated A549 cells from apoptosis.Keywords: chronic obstructive pulmonary disease, lncRNA RP11-521C20.3, BMF, apoptosis

Some constructions of the molecular model for reactive molecular dynamics (RMD) simulations have neglected the effect of molecular weight on the RMD results. A computational methodology for generating structural models of amorphous ultrahigh molecular weight polyethylene (UHMWPE) with different degrees of polymerization was thus proposed. The methodology was then used in RMD simulations of three types of molecular models for UHMWPE with 20, 40, and 80 vinyl monomers. The accuracy of the model has been discussed by comparing the RMD results with experimental data previously available in the literature. Results have confirmed that the atomic model with larger molecular weight allows (i) exact calculations of the diffusion coefficient and (ii) accurate prediction of the cross-linked reaction. The RMD simulations provide the basic data for understanding and further studying the chemical reaction of other interesting macromolecules.

A method is reported for the determination of diphenylamine and butylated hydroxytoluene in mineral and synthetic oil. The procedure used differential pulse voltammetry with a glassy carbon electrode. This method was then used for determining these antioxidants in supporting electrolyte consisting of dilute sulfuric acid and sodium dodecyl sulfonate in ethanol. Anodic peaks were obtained for both analytes. Oxidation peaks at 250 mV were observed from a mixture of butylated hydroxytoluene and dinonyl diphenylamine, allowing their simultaneous determination. This approach was successfully used for the determination of dinonyl diphenylamine and butylated hydroxytoluene in fortified mineral and synthetic oils with good accuracy and precision.

In a pot experiment with brown-yellow soil, this paper studied the effects of different concentration selenium on the growth and activated oxygen- scavenging system of Oryza sativa. The results showed that low concentration Se (8 mg x kg(-1)) had a promoting effect on the wheat biomass, chlorophyll a, chlorophyll a/b, and activated oxygen- scavenging system, while high concentration Se (16 mg x kg(-1)) was in adverse. Soil Se concentration had a significant correlation with root biomass, shoot biomass, chlorophyll a/b, MDA, SOD, CAT, POD. It was defined by the pot experiment that 10% inhibition rate of root or shoot biomass could be regarded as critical value, and the critical content of soil Se was estimated to be 21 mg x kg(-1).

The cycling and balance of copper in 8 cropping systems, i.e., wheat-rice, rice-rice, rape-soybean, rape-peanut, wheat-sesame, wheat-cotton, pepper-cabbage and radish-eggplant in Jianghan plain of Hubei Province were studied. The results showed that the main output of copper was crop harvesting, up to 85.9%-95.1% of total output, and the output of copper by field runoff and soil leaching was low. The main inputs of copper were organic fertilizer, rainfall, falldrop, and natural return. The inputs of copper from inorganic fertilizer and seeds (seedlings) were low. The balance analysis pointed out that copper had an accumulative trend in two patterns of rice and commercial vegetable ecosystem, and was in balance in upland field ecosystem.

The ester base oil of dioctyl adipate (DOA) was oxidized in an oven at 200 °C for 30 h, and variations in the physicochemical and tribological properties were studied. To investigate the thermal-oxidation mechanism, the thermal-oxidation products were analyzed by gas chromatography–mass spectrometry (GC−MS), and the thermal-oxidation process was simulated using visual reactive force field molecular dynamics (ReaxFF MD). The results indicated that the total acid number (TAN) increased significantly because of the presence of 14% carboxylic acids and low molecular weight monoesters. The tribological properties were improved by the formation of the strongly polar carboxylic acids. Additionally, the increase in kinematic viscosity was limited due to the formation of high molecular weight polymerization products and low molecular weight degradation products. Thermal-oxidative degradation and polymerization mechanisms were proposed by combining ReaxFF MD simulations and GC−MS results.