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Three limonoids cipaferoids A–C (1–3) representing two different scaffolds were isolated from Cipadessa baccifera. Their structures were completely assigned by spectroscopic data, CD exciton chirality method, and X‐ray crystallography. Compounds 2 and 3 exhibited moderate antimalarial activity with IC50 values of 9.3±0.1 and 14.7±4.8 μmol•L–1, respectively. [ABSTRACT FROM AUTHOR]

Six new mexicanolide-type limonoids, dysoxylumasins A-F ( 1- 6), together with eight known compounds, namely litseagermacrane, 15-methoxyisodauc-3-ene-1 β,5 α-diol, isodauc-6-ene-10 β,14-diol, 4- epi-isodauc-6-ene-10 β,14-diol, 2 α,3 α,4 β-trihydroxypregnan-16-one, 1,7-phenanthrenedimethanol, spicatin, and aurantiamide, were isolated from the leaves and twigs of Dysoxylum mollissimum Bl. Their structures were established by the analyses of spectroscopic data. [ABSTRACT FROM AUTHOR]

Colonization of human stomach by the bacterium Helicobacter pylori is a major causative factor for gastrointestinal illnesses and gastric cancer. However, the discovery of anti- H. pylori agents is a difficult task due to lack of mature protein targets. Therefore, identifying new molecular targets for developing new drugs against H. pylori is obviously necessary. In this study, the in-house potential drug target database (PDTD, ) was searched by the reverse docking approach using an active natural product (compound 1) discovered by anti- H. pylori screening as a probe. Homology search revealed that, among the 15 candidates discovered by reverse docking, only diaminopimelate decarboxylase (DC) and peptide deformylase (PDF) have homologous proteins in the genome of H. pylori. Enzymatic assay demonstrated compound 1 and its derivative compound 2 are the potent inhibitors against H. pylori PDF ( HpPDF) with IC50 values of 10.8 and 1.25 μM, respectively. X-ray crystal structures of HpPDF and the complexes of HpPDF with 1 and 2 were determined for the first time, indicating that these two inhibitors bind well with HpPDF binding pocket. All these results indicate that HpPDF is a potential target for screening new anti- H. pylori agents. In addition, compounds 1 and 2 were predicted to bind to HpPDF with relatively high selectivity, suggesting they can be used as leads for developing new anti- H. pylori agents. The results demonstrated that our strategy, reverse docking in conjunction with bioassay and structural biology, is effective and can be used as a complementary approach of functional genomics and chemical biology in target identification. [ABSTRACT FROM AUTHOR]

As a brassinosteroid (BR), 24-epibrassinolide (24-epiBL) has been widely used to enhance the resistance of plants to multiple stresses, including salinity. Black locust (Robinia pseudoacacia L.) is a common species in degraded soils. In the current study, plants were pretreated with three levels of 24-epiBL (0.21, 0.62, or 1.04 µM) by either soaking seeds during the germination phase (Sew), foliar spraying (Spw), or root dipping (Diw) at the age of 6 months. The plants were exposed to salt stress (100 and 200 mM NaCl) via automatic drip-feeding (water content ~40%) for 45 days after each treatment. Increased salinity resulted in a decrease in net photosynthesis rate (Pn), stomatal conductance (Gs), intercellular:ambient CO2 concentration ratio (Ci/Ca), water-use efficiency (WUEi), and maximum quantum yield of photosystem II (PSII) (Fv/Fm). Non-photochemical quenching (NPQ) and thermal dissipation (Hd) were elevated under stress, which accompanied the reduction in the membrane steady index (MSI), water content (RWC), and pigment concentration (Chl a, Chl b, and Chl). Indicators of oxidative stress (i.e., malondialdehyde (MDA) and antioxidant enzymes (peroxidase (POD) and superoxide dismutase (SOD)) in leaves and Na+ content in chloroplasts increased accompanied by a reduction in chloroplastid K+ and Ca2+. At 200 mM NaCl, the chloroplast and thylakoid ultrastructures were severely disrupted. Exogenous 24-epiBL improved MSI, RWC, K+, and Ca2+ content, reduced Na+ levels, maintained chloroplast and thylakoid membrane structures, and enhanced the antioxidant ability in leaves. 24-epiBL also substantially alleviated stress-induced limitations of photosynthetic ability, reflected by elevated chlorophyll fluorescence, pigment levels, and Pn. The positive effects of alleviating salt stress in R. pseudoacacia seedlings in terms of treatment application was Diw > Sew > Spw, and the most positive impacts were seen with 1.04 µM 24-epiBL. These results provide diverse choice for 24-epiBL usage to defend against NaCl stress of a plant. [ABSTRACT FROM AUTHOR]

The influence of acid rain on forest trees includes direct effects on foliage as well as indirect soil-mediated effects that cause a reduction in fine-root growth. In addition, the concentration of NO 3 − in acid rain increases with the rapidly growing of nitrogen deposition. In this study, we investigated the impact of simulated acid rain with different SO 4 2 − /NO 3 − (S/N) ratios, which were 5:1 (S), 1:1 (SN) and 1:5 (N), on fine-root growth from March 2015 to February 2016. Results showed that fine roots were more sensitive to the effects of acid rain than soils in the short-term. Both soil pH and fine root biomass (FRB) significantly decreased as acid rain pH decreased, and also decreased with the percentage of NO 3 − increased in acid rain. Acid rain pH significantly influenced soil total carbon and available potassium in summer. Higher acidity level (pH = 2.5), especially of the N treatments, had the strongest inhibitory impact on soil microbial activity after summer. The structural equation modelling results showed that acid rain S/N ratio and pH had stronger direct effects on FRB than indirect effects via changed soil and fine root properties. Fine-root element contents and antioxidant enzymes activities were significantly affected by acid rain S/N ratio and pH during most seasons. Fine-root Al ion content, Ca/Al, Mg/Al ratios and catalase activity were used as better indicators than soil parameters for evaluating the effects of different acid rain S/N ratios and pH on forests. Our results suggest that the ratio of SO 4 2 − to NO 3 − in acid rain is an important factor which could affect fine-root growth in subtropical forests of China. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to assess the prognostic value for NSCLC patients who were scheduled to receive lung cancer radical resection., Methods: In this cohort study (Dec.2014-Feb.2016), patients with non-small cell lung cancer (NSCLC) who underwent radical lung cancer thoracotomy were enrolled and accessed at postoperative complications, one-year overall survival (OS) and relapse-free survival (RFS). The preoperative PLR and NLR of all patients were calculated based on preoperative complete blood counts. Univariate and multivariate Cox regression analyses were performed to determine the associations of PLR and NLR with OS and RFS., Results: A total of 174 NSCLC patients were studied. The results indicated that both high PLR (>148.6) and NLR (>2.9) were related to a high rate of postoperative pulmonary complications significantly (49.3%vs.29.1%, P = 0.007; 50.7% vs. 28.6%, P = 0.003). Moreover, NSCLC patients with a high PLR level (> 148.6) was significantly associated with a lower one-year OS (90.3% vs. 77.5%, P = 0.034)., Conclusions: Preoperative PLR and NLR were good prognostic factors for postoperative pulmonary complications and OS in NSCLC patients undergoing radical lung cancer surgery. Thus, blood PLR and NLR would be helpful as a prognostic tool before radical lung cancer surgery.