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Five tigliane (1−5) and one ingenane (6) diterpenoids were isolated from the ethanol extract of Euphorbia tirucalli. The structures of these compounds were identified based on analysis of their spectroscopic data. Among them, compound 12-O-(2E,4E,6E,8E-tetradecatetraenoyl)-13-O-isobutyroyl-4β-deoxyphorbol (1) was a new tigliane. The Rho123 effluxion assay showed that tiglianes with a trans-fused 5/7 ring system such as compounds 1, 2, and 4 had potent inhibitory activity against P-glycoprotein in HepG2/ADR cells. [ABSTRACT FROM AUTHOR]

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One new clerodane-type furanoditerpenoid tinosinoid A (1) and nine new nor-clerodane analogs tinosinoids B–J (2−10) have been isolated from the stems of Tinospora sinensis. The structures of the new compounds with absolute configurations have been elucidated by spectroscopic means, including MS, NMR and ECD techniques, as well as chemical correlation. Compound 1 is a rare sulfur-containing clerodane diterpenoid incorporating a 2-mercaptoethanol unit via a thioether bond, while compounds 4/5 and 9 represent two pairs of unusual equilibrium regioisomers through an interesting intramolecular transesterification. Our bioassays established that 1 and 8 displayed moderate antiproliferative effects against two human tumor cell lines, and 9 and 10 showed significant α-glucosidase inhibitory activities. A kinetics study revealed that compound 10 was a noncompetitive α-glucosidase inhibitor, and its possible binding mode to the enzyme was further probed by molecular docking experiments. [ABSTRACT FROM AUTHOR]

Ten thiophene derivatives (1–10), including two previously undescribed ones (1 and 2), have been obtained and structurally characterized from the aerial parts of a traditional Chinese herb Eclipta prostrata. Six of them with one chiral center were identified to be scalemic mixtures, and the pure enantiomers of two isolates (1 and 3) were successfully separated via chemical derivatization and chiral HPLC, with the absolute configurations being established by analysis of optical rotations. All the thiophenes were subjected to a series of assays and compounds 9 and 10 exhibited mild antibacterial activity against Staphylococcus aureus. [ABSTRACT FROM AUTHOR]

Background and aims: Male breast cancer is an uncommon disease. The benefit of adjuvant chemotherapy in the treatment of male breast cancer patients has not been determined. The aim of this study was to explore the value of adjuvant chemotherapy in men with stage I–III breast cancer, and we hypothesized that some male patients may safely skip adjuvant chemotherapy. Methods: Male breast cancer patients between 2010 and 2015 from the Surveillance Epidemiology and End Results database were included. Univariate and multivariate Cox analyses were used to analyse the factors associated with survival. The propensity score matching method was adopted to balance baseline characteristics. Kaplan–Meier curves were used to evaluate the impacts of adjuvant chemotherapy on survival. The primary endpoint was survival. Results: We enrolled 514 patients for this study, including 257 patients treated with chemotherapy and 257 patients without. There was a significant difference in overall survival (OS) but not in breast cancer-specific survival (BCSS) between the two groups (p < 0.001 for OS and p = 0.128 for BCSS, respectively). Compared with the non-chemotherapy group, the chemotherapy group had a higher 4-year OS rate (97.5% versus 95.2%, p < 0.001), while 4-year BCSS was similar (98% versus 98.8%, p = 0.128). The chemotherapy group had longer OS than the non-chemotherapy group among HR+, HER2–, tumour size >2 cm, lymph node-positive male breast cancer patients (p < 0.05). Regardless of tumour size, there were no differences in OS or BCSS between the chemotherapy and non-chemotherapy cohorts for lymph node-negative patients (OS: p > 0.05, BCSS: p > 0.05). Adjuvant chemotherapy showed no significant effects on both OS and BCSS in patients with stage I (OS: p = 0.100, BCSS: p = 0.858) and stage IIA breast cancer (OS: p > 0.05, BCSS: p > 0.05). Conclusion: For stage I and stage IIA patients, adjuvant chemotherapy could not improve OS and BCSS. Therefore, adjuvant chemotherapy might be skipped for stage I and stage IIA male breast cancer patients. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Central South University is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A magnetic and thermal design of high-temperature superconducting (HTS) quadrupole magnet for newly developed superconducting proton cyclotron was presented in this research. With superconducting technology, the design can reduce the magnet size and remove the heat loads more efficiently. Calculations are conducted with finite element method (FEM) to study the quadrupole magnet's magnetic and thermal properties. For the magnet cold-mass and cryostat system, the heat load is mainly generated by conduction and radiation. Multilayer thermal insulation and G10 supports are used to restrict them. The magnetic field distribution in the HTS coils is calculated to consider the critical current degradation of the YBCO tapes. The effects on the field gradient quality in relation to the pole tip profile and end chamfer are analyzed. The sixth multipole component in the integral field can be improved with end chamfer. Finally, a 20 T/m HTS quadrupole magnet with integral field uniformity less than 0.05% out to 75% of the inscribed radius is proposed. [ABSTRACT FROM AUTHOR]

The complete mitogenome sequence of Ochotona hyperborea was determined using long PCR. The genome was 17,063 bp in length and contained 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes, one origin of L strand replication, and one control region. The overall base composition of the heavy strand is A (31.1%), C (28.7%), T (26.3%), and G (13.9%). The base compositions present clearly the A–T skew, which is most obvious in the control region and protein-coding genes. Mitochondrial genome analyses based on MP, ML, NJ, and Bayesian analyses yielded identical phylogenetic trees. This study verifies the evolutionary status of Ochotona hyperborea in Ochotonidae at the molecular level. The mitochondrial genome would be a significant supplement for the Ochotona hyperborea genetic background. The eight Ochotona species formed a monophyletic group with the high bootstrap value (100%) in all examinations. [ABSTRACT FROM AUTHOR]

Five selaginellin derivatives (1 and 3-6) including a new one, selaginellin T (1), and a new triarylbenzophenone analog, selagibenzophenone A (2), were isolated from the whole plants of Selaginella pulvinata. Their structures were determined by 1D- and 2D-NMR and HR-ESI-MS data. Selagibenzophenone A (2) is the first example of naturally occurring triarylbenzophenone. The results of the phosphodiesterase-4 (PDE4) inhibitory screening assays showed that compounds 1−6 exhibited potent activities with the IC50 values in the range of 1.04−9.35 μM. [ABSTRACT FROM AUTHOR]

Phytochemical investigation of Cephalotaxus sinensis has led to the isolation of a new bisabolane sesquiterpenoid (1), a new abietane diterpenoid (2), and 13 known compounds (3–15). Their structures were elucidated by extensive spectroscopic analysis (MS, UV, IR, and NMR). [ABSTRACT FROM AUTHOR]

In the present work, the gas flow pressure drop and gas-solid heat transfer characteristics in sinter bed layer of vertical tank were studied experimentally on the basis of the homemade experimental setup. The gas flow pressure drop through the sinter bed layer was measured with different gas velocity and particle diameters, as well as the sinter and air temperatures. The influences of gas superficial velocity and particle diameter on the gas flow pressure drop and gas solid heat transfer in sinter bed layer were analyzed in detail. The revised Ergun's correlation and gas solid heat transfer correlation were obtained according to the regression analysis of experimental data. It is found that, the pressure drop of unit bed layer height gradually increases as a quadratic relationship with increasing the gas superficial velocity, and decreases as an exponential relationship with the increase of sinter particle diameter. For a given sinter temperature, the heat transfer coefficient in sinter bed layer increases with increasing the gas superficial velocity, and increases with decreasing the sinter particle diameter. In addition, the heat transfer coefficient also gradually increases with increasing the sinter temperature at the same gas superficial velocity and sinter particle diameter. The mean deviations between the experimental data obtained from this work and the values calculated by the revised Ergun's correlation and the experimental heat transfer correlation are 7.22% and 4.22% respectively, showing good prediction. [ABSTRACT FROM AUTHOR]

The nun moth, Lymantria monacha L., is one of the most important defoliators of Eurasian coniferous forests. Outbreaks during 2011-2015 in the natural/planted larch, and larch-birch mixed forests of the Greater Khingan Range in Inner Mongolia, China, caused tremendous timber losses from severe defoliation and tree mortality. A series of trapping experiments were conducted in these outbreak areas to evaluate the efficacy of a synthetic species-specific pheromone lure based on the female pheromone blend of European nun moth populations. Our results clearly show that the nun moth in Inner Mongolia is highly and specifically attracted to this synthetic pheromone, with few gypsy moths ( Lymantria dispar) captured. Flight activity monitoring of L. monacha male moths using pheromone-baited Unitraps at 2 locations during the summer of 2015 indicated that the flight period started in mid-July, peaking in early August at both locations. Based on male moth captures, there was a strong diurnal rhythm of flight activity throughout the entire scotophase, peaking between 22:00 and 24:00. Unitraps and wing traps had significantly and surprisingly higher catches than the gypsy moth traps. Unitraps fastened to tree trunks 2 m above ground caught significantly more male moths than those at the ground level or at 5 m height. Male L. monacha moths can be attracted to pheromone-baited traps in open areas 150-200 m distant from the infested forest edge. Our data should allow improvement on the performance of pheromone-baited traps for monitoring or mass-trapping to combat outbreaks of this pest in northeastern China. [ABSTRACT FROM AUTHOR]

The Jianpudong No. 4 tunnel is a shallow tunnel, which belongs to Shaoshan County scenic highway in Hunan province, China and whose surrounding rock is weak. According to its characteristics, the field monitoring tests and numerical analysis were done. The mechanical characteristics of shallow tunnels under weak surrounding rock and the stress-strain rule of surrounding rock and support were analyzed. The numerical analysis results show that the settlement caused by upper bench excavating accounts for 44% of the total settlement, and the settlement caused by tunnel upper bench supporting accounts for 56% of the total settlement. The maximum axial force of shotcrete lining is 177.2 kN, which locates in hance under the secondary lining. The maximum moment of shotcrete lining is 5.08 kN·m, which locates in the arch foot. The stress curve of steel arch has three obvious stages during the tunnel construction. The maximum axial force of steel arch is 297.4 kN, which locates in tunnel vault. The axial forces of steel arch are respectively 23.5 kN and −21.8 kN, which is influenced by eccentric compression of shallow tunnel and locates in hance. The results show that there is larger earth pressure in tunnel vault which is most unfavorable position of steel arch. Therefore, the advance support should be strengthened in tunnel vault during construction process. [ABSTRACT FROM AUTHOR]

There has been little research conducted regarding autophagy in oral squamous cell carcinoma ( OSCC). Given the prevalence of oral cancers which are OSCC and the severe side effects of current treatments, there is a pressing need to develop effective alternative therapies. In this study, we have endeavored to explore the biological characteristics of oral squamous cell carcinoma cell line KB cells, in particular with regard to the role played by autophagy in their survival. Autophagy was activated by nutrient depletion via culturing cells in Earle's balanced salts ( EBSS) and was measured via indices relating to Beclin 1, microtubule-associated protein light chain 3 ( MAPLC3, LC3), p62, and Green fluorescent protein-light chain 3 plasmid transfection ( GFP- LC3). Cell death and apoptosis induced by nutrient depletion was measured using both MTT assay and flow cytometry ( FCM). Compared to initial levels at 0 h, Beclin 1 density in EBSS-treated cells was found to have increased at 6, 12, and 18 h in a time-dependent manner and was found to have subsequently declined at 24 and 48 h. p62 levels, LC3- II/ LC3-I ratio, and GFP- LC3 levels increased at 6, 12, 18, 24, and 48 h in a time-dependent manner. 3-methyladenine (3- MA) was found to inhibit autophagy and the expression of Beclin 1 and significantly enhanced nutrient depletion-induced apoptosis and death. We concluded that nutrient depletion enhances OSCC cell autophagy in time-course patterns and that the inhibition of autophagy augments apoptosis in OSCC cells. We also deduced that Beclin 1 takes part in the development and progression of autophagy, potentially playing an important role in the crosstalk between apoptosis and autophagy in OSCC cells. These findings suggest that nutrient depletion may be an effective way to explore autophagy and that autophagy inhibitors should be investigated as a potential novel agent for the adjuvant treatment of human OSCC. [ABSTRACT FROM AUTHOR]

ABSTRACT Two pairs of new neolignan enantiomers, (±)-torreyayunan A ( 1a/ 1b) and (±)-torreyayunan B ( 2a/ 2b), featuring a rare C-8 − C-9′ linked skeleton, were isolated from leaves and twigs of Torreya yunnanensis. Their absolute configuration involving two chiral centers was determined by combined spectral and Density Functional Theory (DFT) calculation. This is the first report of the absolute configuration of this group of neolignans. Chirality 26:825-828, 2014. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Based on the slip-line field theory, a two-dimensional slip failure mechanism with mesh-like rigid block system was constructed to analyze the ultimate bearing capacity problems of rough foundation within the framework of the upper bound limit analysis theorem. In the velocity discontinuities in transition area, the velocity changes in radial and tangent directions are allowed. The objective functions of the stability problems of geotechnical structures are obtained by equating the work rate of external force to internal dissipation along the velocity discontinuities, and then the objective functions are transformed as an upper-bound mathematic optimization model. The upper bound solutions for the objective functions are obtained by use of the nonlinear sequential quadratic programming and interior point method. From the numerical results and comparative analysis, it can be seen that the method presented in this work gives better calculation results than existing upper bound methods and can be used to establish the more accurate plastic collapse load for the ultimate bearing capacity of rough foundation. [ABSTRACT FROM AUTHOR]