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Numerous antitumor drugs exhibited excellent anti-proliferation activities, discovered from natural products. Oridonin is isolated from a traditional Chinese medicine Isodon rubescens, and it exhibit various biological functions including anticancer, anti-inflammation, antibacterial, and so on. The anticancer mechanisms of oridonin include apoptosis, autophagy, cell cycle arrest, and so on. However, clinical research and application of oridonin has been hampered, due to the poor pharmaceutical property. So many studies on oridonin have been explored in the purpose of improve the pharmaceutical property, including investigation of the mechanism of action in depth and structural modification. In this review, we summarized oridonin and oridonin derivatives as potential anticancer agents, and detailed discussion on biological properties, mechanism of actions and potential for overcoming therapeutic resistance. [ABSTRACT FROM AUTHOR]

A simplified finite element method (FEM) simulation method has been established and validated for analyzing the sound absorption mechanism of structures with periodic axisymmetric cavities. Combined with genetic algorithm, the simplified FEM method is used to optimize the sound absorption coefficient of the structure containing periodic cylindrical cavities and variable cross section cavities. The result of variable section cavities is much better than the case of cylindrical cavities. The effect of cavity shape on sound absorption mechanism is discussed through energy dissipation, structure deformation and modal analysis of the absorption structures. It is found that the cavity structure resonances include bending vibration of the surface layer and radial motion of particles near the cavities. The radial motion also changes along the axial direction. Adding geometric design parameters of the cavity cross section are conducive to moving the radial mode to low frequency. The radial vibration has a great influence on absorption performance, which is more conducive to promoting the conversion of longitudinal waves into transverse waves with more energy dissipation. Finally, a better sound absorption performance is obtained by introducing the material parameter of Young's modulus into the optimization model, indicating that comprehensive consideration of geometry and material parameters for optimization is expected to obtain the desired sound absorption structure in engineering practice. [ABSTRACT FROM AUTHOR]

Magnesium hydride (MgH2) is a candidate material for hydrogen storage. MgH2–AlH3 composite shows superior hydrogen desorption properties than pure MgH2. However, this composite still suffers from poor cycling performance. In this work, NbF5 was utilized to improve the cycling properties of the MgH2–AlH3 composite. Cycling hydrogen desorption studies show that NbF5 significantly improves the cycling stability of MgH2–AlH3. The MgH2–AlH3–NbF5 composite can release about 2.7 wt% of hydrogen at 300 °C for 1 h and the hydrogen desorption capacity can maintain at 2.7 wt% for more than 100 cycles. In comparison, the hydrogen desorption capacity of the MgH2–AlH3 composite is decreasing with the cycle number increasing. The capacity is reduced from a maximum value of 3.3 wt% to about 1.0 wt% after 40 cycles. Brunauer–Emmett–Teller (BET) surface area measurements show that the particle size of MgH2–AlH3 composite decreases after cycling, which means pulverization of the composite. NbF5 can to some extent suppress the pulverization of the composite during cycling, which partially contributes to the improvement of the cycling hydrogen desorption properties of the material. NbF5 addition significantly improves the cycling hydrogen desorption properties of the MgH2−AlH3 composite. [ABSTRACT FROM AUTHOR]

Abstract : Novel phenothiazine-dithiocarbamate analogues were designed by molecular hybridization strategy and synthesized and evaluated for their anticancer activity in vitro against three selected cancer cell lines (EC-109, MGC-803, and PC-3). The preliminary structure-activity relationship (SAR) for this phenothiazine-dithiocarbamate hybrids is explored. Among all analogues, 2-oxo-2-(10H-phenothiazin-10-yl)ethyl 4-ethylpiperazine-1-carbodithioate ( 8a) showed the most potent inhibitory activity with an $$\hbox {IC}_{50}$$ value of $$11.59\,\upmu \hbox {M}$$ against PC-3 cells. In addition, compound 8a could arrest the cell cycle at the G1 phase and regulate the expression of G1 checkpoint-related proteins, suggesting that phenothiazine-dithiocarbamate hybrids might be useful as cell cycle blockers. Graphical Abstract: [ABSTRACT FROM AUTHOR]

A multiresidue method has been optimized and validated for the rapid determination of 12 veterinary drugs belonging to β-agonists and β-lactam antibiotics in porcine muscle. It has been based on liquid chromatography-tandem mass spectrometry and a simple extraction procedure using acetonitrile/HO. The extract was centrifuged, and the supernatant was directly analyzed by LC-MS/MS in positive ion mode with multiple reaction monitoring (MRM). The linearity of each analyte was almost the coefficient of determination ( r) > 0.99. Mean recoveries for all analytes ranged from 74.6 to 115.3% with intra-day RSD ≤ 17.2% and inter-day RSD ≤18.1%. Limits of detection (LODs) and limits of quantification (LOQs) ranged from 0.4 to 2.0 and 1.0 to 8.0 ng/g, respectively. Finally, the validated method was successfully applied to the quantitative analysis of real samples, and clorprenaline was detected in one out of 15 pork samples. [ABSTRACT FROM AUTHOR]

A series of novel coumarin derivatives were synthesized from commercially available chemical agents. All prepared compounds were evaluated for their in vitro antiproliferative activity against five selected human cancer cell lines (EC109, MGC-803, PC-3, MCF-7, and EC9706) and their in vitro antimicrobial activity against E. coli and M. albicans. 4-(3-Bromopropoxy)-2 H-chromen-2-one exhibited the highest growth inhibition against MGC-803 cell line (IC 47.7 μM) and 7-(2-bromoethoxy)-2 H-chromen-2-one exhibited the highest growth inhibition against MCF-7 cell line (IC 48.3 μM). The latter compound was also the most active against E. coli (MIC 0.27 μg/ml). [ABSTRACT FROM AUTHOR]

This study examined young adults' written accounts of intergenerational communication in conflict situations in the People's Republic of China. Using a content analysis approach, this study identified five major types of initiating factors that precipitated intergenerational conflict. Old-to-young criticism was most frequent, followed by illegitimate demand and rebuff. The least frequent initiating factors included young-to-old criticism and disagreement/generation gap. In addition, results indicated that more rebuffs were from nonfamily elders than from family elders, whereas disagreement with family elders was more frequent than with non-family elders. Proportionally speaking, no differences emerged between family and nonfamily elders for criticism (both old-to-young and young-to-old) and illegitimate demand. Results are discussed with respect to research in intergenerational communication, interpersonal conflict, and the Chinese socio-cultural norm of hierarchy and filial piety. [ABSTRACT FROM AUTHOR]

This study examined intergenerational communication schemas by investigating young adults' cognitive representations of communication with older adults in Taiwan. Forty-one Taiwanese college students described conversations with an older adult in response to a variety of interviewer prompts. Transcripts were read and content analyzed by the first two authors. To capture the characteristics of the conversation descriptions, eleven coding dimensions were generated based on schema theory, and all conversation descriptions were coded along these dimensions. Coding results were submitted to hierarchical cluster analysis, yielding five schemas: Mutually satisfying, helping, mixed feelings, small talk, and mutually unpleasant conversations. Results are discussed in terms of similarities and differences from Harwood, McKee and Lin's (2000) study, schema theory, intergenerational communication, and Chinese cultural norms. [ABSTRACT FROM AUTHOR]