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Two new compounds including a new 3-arylcoumarin liquiritcoumarin (1), and a new flavonoid glycoside crotoliquiritin (2), together with twelve known compounds (3–14) were isolated from the radix and rhizome of Glycyrrhiza uralensis. Their structures were elucidated on the basis of extensive spectroscopic data analyses. All of the compounds were evaluated for the cytotoxic activities. Only compound 5 showed moderate effects with IC50 of 11.46 μM for A549 cells and IC50 of 7.38 μM for NCI-H292 cells. Compounds 1 and 2 were demonstrated to be Nrf2 pathway activators by using a stable antioxidant response element (ARE)-dependent reporter gene assay together with immunoblot and immunofluorescence analysis. [ABSTRACT FROM AUTHOR]

Abstract The main purpose of this paper is to study the number of the square-free number sequence, and give two interesting asymptotic formulas for it. At last, give another asymptotic [...]

Purpose: Carbapenem-resistant Klebsiella pneumoniae (CRKP) represents a serious problem worldwide. Herein, we describe the evolution of ceftazidime–avibactam (CZA) resistance by sequencing clinical isolates from a patient with CRKP infection undergoing CZA treatment. Patients and Methods: In this study, six CRKP strains were isolated from sputum and blood samples of a patient with CRKP infection after intracerebral hemorrhage. Two strains were selected for whole-genome analysis. Results: Drug susceptibility testing showed that the MIC of CZA for CRKP strains isolated after 6 days of CZA treatment was 64-fold higher than that for three CRKP strains isolated before CZA treatment (4 vs > 256 μg/mL), whereas the MIC of imipenem and meropenem was 128-fold (> 32 vs 0.25 μg/mL) and 16-fold (> 32 vs 2 μg/mL) lower relatively, respectively. Multilocus sequence typing showed that all six CRKP strains isolated from the patient were ST11 and pulsed-field gel electrophoresis confirmed that they were of the same clone. Two strains were selected for whole-genome analysis. The aspartic acid residue at position 179 in the Ω loop was replaced by a tyrosine residue in the resistant strain, and the plasmid carried a blaKPC-2 to blaKPC-33 mutation. The results of the modified carbapenem inactivation method and the carbapenemase inhibitor enhancement and colloidal gold enzyme immunochromatographic assays for blaKPC-33 were negative. Conclusion: This is the first report from Henan to show that treatment with CZA for 6 days can cause mutations and change the phenotype from CZA sensitive to resistant. Therefore, routine testing for drug susceptibility and carbapenemase phenotypes should be conducted during treatment with CZA, and genotype determination is essential. [ABSTRACT FROM AUTHOR]

Phytochemical studies on the leaves of Epimedium koreanum Nakai have resulted in the discovery of two new flavonol glycosides, koreanoside F (1) and koreanoside G (2), along with six known flavonoids. Their structures were elucidated on the basis of HRESIMS, UV, IR, 1 D NMR and 2 D NMR data. Absolute configurations of 1 and 2 was further determined by 13C-NMR spectra with gate decoupling (GD). All of the compounds were evaluated for cytotoxic activities by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazoliumbromide (MTT) assay. The results indicated that compounds 3, 5, 6, 7 and 8 inhibited the proliferation of A549 and NCI-292 cells with IC50 values of 5.7–23.5 μM. Real-time monitoring in three kinds of lung cancer cells and a kind of human bronchial epithelial cells treated with compound 6 was also assessed. [ABSTRACT FROM AUTHOR]

1,7‐Bis(4‐hydroxyphenyl)‐1,4‐heptadien‐3‐one (EB30) is a diarylheptanoid‐like compound isolated from Viscum coloratum. This curcumin analog exhibits significant cytotoxic activity against HeLa, SGC‐7901, and MCF‐7 cells. However, little is known about the anticancer effects and mechanisms of EB30 in human lung cancer. The current study reports that EB30 significantly reduced the cell viability of A549 and NCI‐H292 human lung cancer cells. Further examination revealed that EB30 not only induced cell cycle arrest and promoted the generation of reactive oxygen species (ROS) but also induced cell apoptosis through the intrinsic and extrinsic signaling pathways. Furthermore, EB30 upregulated the expression levels of p‐ERK1/2 and p‐P90RSK, whereas downregulating the phosphorylation of Akt and P70RSK. Cell viability was further inhibited by the combination of EB30 with LY294002 (a specific PI3K inhibitor) or U0126 (a MEK inhibitor). The current study indicates that EB30 is a potential anticancer agent that induces cell apoptosis via suppression of the PI3K/Akt pathway and activation of the ERK1/2 pathway. The results of this study indicated that EB30 could decrease cell viability, induce apoptosis, and cell cycle arrest. The induction of apoptosis was found to be mediated through the mitochondrial intrinsic pathway and extrinsic pathway. The apoptotic effects of EB30 were mediated by suppressing the PI3K/Akt pathway, whereas activating the ERK1/2 signaling. [ABSTRACT FROM AUTHOR]

Oxidative stress has been suggested to play an important role in neuronal injury. Ethyl gallate (EG) is the ethyl ester of gallic acid which has been acknowledged as an antioxidant. We previously demonstrated that EG effectively inhibited H2O2-induced cytotoxicity and decreased the ROS levels in PC12 cells, while the relevant mechanisms of action of this compound remain largely uncharacterized. The present study was carried out in an attempt to clarify the underlying mechanisms of EG against H2O2-induced neurotoxicity in PC12 cells. EG pretreatment attenuated H2O2-induced mitochondrial dysfunction as indicated by the decreased caspase-9/−3 activation, PARP cleavage, mitochondrial membrane potential (MMP) depletion, Bax/Bcl-2 ratio, cytochrome c release and ROS overproduction. Furthermore, EG treatment resulted in nuclear translocation of Nrf2 along with increased expression of ARE-dependent cytoprotective genes, such as γ-GCS and NQO1, which indicated EG as an Nrf2 pathway activator. Silencing of Nrf2 signaling by siRNA abrogated the protective effects offered by EG on H2O2-induced PC12 cells injury, which suggested the important role of Nrf2 pathway in the protection of EG against oxidative stress induced PC12 cell apoptosis. These results taken together indicated that EG protects PC12 cells against H2O2-induced cell mitochondrial dysfunction possibly through activation of Nrf2 pathway. EG might be a potential candidate for further preclinical study aimed at the prevention and treatment of neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

Two new 2-arylbenzofuran derivatives, moracinfurol A and B (1-2), and ten known compounds (3-12) were isolated from the leaves of Morus alba. Their structures were determined on the basis of spectroscopic analysis including 1D, 2D NMR and HR-ESI-MS. All of the 2-arylbenzofuran derivatives were evaluated for cytotoxicity against A549 cells. Some cytotoxic 2-arylbenzofuran derivatives might induce autophagy characterized by the accumulation of LC-3 Ⅱ. [ABSTRACT FROM AUTHOR]