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Summary: This paper addresses the issue of distributed finite‐time attitude coordination control of spacecraft formations with multiple constraints on angular velocities and control torques. First, the multiple constrained problem is transformed into a bounded issue by virtue of the nonlinear transformation technique and an input saturation model. Next, the nearest neighbor rule is applied to deal with the problem of the unavailability of the leader's information to all followers. Then, a distributed attitude coordination control algorithm is derived to enforce that all attitude tracking errors can converge to a neighborhood around the origin in finite time even when there exist multiple constraints and external disturbances imposed on spacecraft systems. Finally, several numerical simulation examples are presented to illustrate the efficiency of the derived method. [ABSTRACT FROM AUTHOR]

In this paper, we study the uniqueness of nodal radial solutions to nonlinear elliptic equations in the unit ball in ℝ3$$ {\mathrm{\mathbb{R}}}^3 $$. Under suitable conditions, we prove that, for any given positive integer k$$ k $$, the problem we considered has at most one solution possessing exactly k−1$$ k-1 $$ nodes. Together with the results presented by Nagasaki [J. Fac. Sci. Univ. Tokyo Sect. IA Math. 36 (2): 211–232, 1989] and Tanaka [Proc. Roy. Soc. Edinburgh Sect. A. 138 (6): 1331–1343, 2008], we can prove that more types of nonlinear elliptic equations have the uniqueness of nodal radial solutions. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to compare the clinical efficacy of laparoscopic liver resection (LLR) and radiofrequency ablation (RFA) in treating solitary hepatocellular carcinoma (HCC) of the hepatic caudate lobe. Methods: Patients with hepatic caudate lobe HCC who underwent LLR or RFA at three hospitals in China between February 2015 and February 2021 were included. In total, 112 patients met the inclusion criteria, of whom 52 underwent RFA and 60 underwent LLR. The outcomes of the two groups were compared and analyzed using propensity score matching (PSM) method. Results: There were no significant differences between the two groups in terms of sex, HBV/HCV positivity, AFP positivity (>100 ng/mL), tumor position, Child–Pugh score, or preoperative liver function tests (ALT, AST, TBIL, ALB, and PT) (p > 0.05). Compared to the LLR group, the RFA group had a shorter operation time, less intraoperative bleeding, and shorter postoperative hospital stay (p < 0.05). There was no statistically significant difference in overall postoperative complications between the two groups (p > 0.05). Despite the larger tumor size, the LLR group had better postoperative recurrence‐free survival (RFS) (p = 0.00027) and overall survival (OS) (p = 0.0023) than the RFA group. After one‐to‐one PSM, 31 LLR patients and 31 RFA patients were selected for further analyses. The advantages of LLR over RFA were observed in terms of RFS (p < 0.0001) and OS (p = 0.00029). Conclusion: LLR should probably be recommended as the preferred method for solitary caudate lobe HCC. [ABSTRACT FROM AUTHOR]

Phenology is highly responsive to environmental changes, particularly in ecologically vulnerable regions that have undergone significant anthropogenic management and rapid climate change. While previous research has mainly focused on interannual variations of specific phenological events such as the start (SOS), peak (POS), and end (EOS) of growing season, little attention has been given to abrupt shifts in long‐term phenological seasonality resulting from land management. In this study, we utilized full temporal details of Moderate Resolution Imaging Spectroradiometer‐derived normalized difference vegetation index to investigate how phenological metrics and seasonality have changed within the Loess Plateau. Our results indicated an earlier initial phase (SOS‐POS) and a prolonged POS‐EOS phenophase. Earlier spring onset was dominated by increasing water availability from the previous autumn, and earlier SOS led to an earlier POS but no significant carryover effect on EOS. In addition, spring onset of grassland was sensitive to precipitation while forest community was strongly influenced by temperature. We also reported significant changes in phenological seasonality across the plateau, and this shift in long‐term seasonality was mainly controlled by growing season precipitation. Moreover, land use/land cover change also played a role with increasing importance after the abrupt change in seasonality. In sum, our findings highlight the importance of water availability in shaping phenological patterns across this semiarid plateau and illuminate shifts in phenological seasonality that are indispensable to a comprehensive understanding of phenology dynamics. [ABSTRACT FROM AUTHOR]

Resveratrol (RES) has various pharmacological bioactivities and its anticancer effects in lung cancer have been proven. However, the underlying mechanisms of action of RES in lung cancer remain unclear. This study focused on Nrf2‐mediated antioxidant systems in RES‐treated lung cancer cells. A549 and H1299 cells were treated with various concentrations of RES at different times. RES decreased cell viability, inhibited cell proliferation, and increased the number of senescent and apoptotic cells in a concentration‐ and time‐dependent manner. Moreover, RES‐induced lung cancer cell arrest at the G1 phase was accompanied by changes in apoptotic proteins (Bax, Bcl‐2, and cleaved caspase 3). Furthermore, RES induced a senescent phenotype along with changes in senescence‐related markers (senescence‐associated β‐galactosidase activity, p21, and p‐γH2AX). More importantly, with prolonged exposure time and increased exposure concentration, intracellular reactive oxygen species (ROS) continuously accumulated, resulting in a decrease in Nrf2 and its downstream antioxidant response elements, including CAT, HO‐1, NQO1, and SOD1. Meanwhile, RES‐induced ROS accumulation and cell apoptosis were reversed by N‐acetyl‐l‐cysteine treatment. Taken together, these results suggest that RES disturb lung cancer cellular homeostasis by destroying the intracellular antioxidant pool to increase ROS production. Our findings provide a new perspective on RES intervention in lung cancer. [ABSTRACT FROM AUTHOR]

Azeotropic organic solvent mixture separation is common in the chemical industry but extremely difficult. Zeolitic imidazolate framework‐67 (ZIF‐67) shows great potential in organic solvent mixture separation due to its rigid micropores and excellent stability. However, due to the fast nucleation rate, it is a great challenge to prepare continuous ZIF‐67 membrane layers with ultrathin thickness. In this study, a hydroxy salt layer with high inducible activity was synthesized as a precursor on different porous substrates to prepare ZIF‐67 membranes at room temperature. The precursor layer enables an intact ZIF‐67 membrane with an ultrathin thickness of 176±12 nm. The experimental and simulation results confirmed that the size sieving through the pore windows and the preferential adsorption of polar solvent molecules provide the ZIF‐67 membrane an unprecedented separation performance such as high separation factors and fluxes, for four types of azeotropic organic solvent mixtures. [ABSTRACT FROM AUTHOR]

A self‐exciting marked point process approach is proposed to model clustered low‐flow events. It combines a self‐exciting ground process designed to capture the temporal clustering behavior of extreme values and an extended Generalized Pareto mark distribution for the exceedances over a subasymptotic threshold. The model takes into account the dependence between the magnitude and occurrence time of exceedances and allows for closed‐form inference on tail probabilities and large quantiles. It is used to analyze daily water levels from the Rivière des Mille Îles (Québec, Canada) and to characterize drought patterns in the Montréal area. The model is useful to generate short‐term probability forecasts and to estimate the return period of major droughts. This information on the drought events is critical to water resource professionals in planning, designing, building, and managing more efficient water resource systems to hedge against the water shortage in case of extreme droughts. [ABSTRACT FROM AUTHOR]

Land surface temperature (LST) is often a direct control on herbaceous plants but has been underappreciated on the alpine grassland phenology in response to climate change. In the present study, we used satellite data of the Moderate Resolution Imaging Spectroradiometer (MODIS) Normalized Difference Vegetation Index (NDVI) and LST products to study the land surface phenology (LSP) of alpine grasslands in response to LST changes in the Qinghai Lake Basin (QLB), which is on the northeastern Tibetan Plateau. Our results showed that LSP, including the start (SOS), end (EOS), and length (GSL) of the growing season, presented high spatial heterogeneity and had significant correlation with landform elevations. Both averaged SOS and EOS across QLB were advanced from 2001 to 2017, but the greater advancement of SOS compared to that of EOS led to an overall prolonged GSL. Daytime LST (LSTd) and nighttime LST (LSTn) had the contrasting effects on SOS (i.e., SOS can be delayed with the increase in LSTd, while it can be advanced with the increase in LSTn). However, increase in LSTd and LSTn in August had the same advancing effect on EOS. Moreover, LSTd played the dominant role in controlling the grassland phenology. Specifically, an 1°C increase in the LSTd in the nongrowing season (i.e., from previous October to April) significantly postponed the SOS by 2.2 d and advanced the EOS by 1.1 d in August. This study highlights the utility and biological relevance of LST in research of grassland phenology and differential impacts of daytime and nighttime LST on grassland phenology. [ABSTRACT FROM AUTHOR]

Using ozone observations, reanalysis data, and climate model simulations, this study investigates in detail the independent and joint influences of the eastern Pacific (EP) El Niño–Southern Oscillation (ENSO) and the quasi‐biennial oscillation (QBO) on stratospheric ozone in the Northern Hemisphere (NH) during winter. Statistically, the stratospheric ozone in the NH in winter increases during El Niño events but decreases during La Niña events. Stratospheric ozone increases in the east wind phases of the QBO (EQBO) and decreases in the west wind phases of the QBO (WQBO). The stratospheric ozone anomalies in the middle and high latitudes caused by ENSO activities are clearly larger than those related to the QBO phase. Since the phases of wave‐1 and wave‐2 planetary waves anomalies related to ENSO activities are broadly similar to those of QBO phases, the joint effect of ENSO and QBO on stratospheric ozone is approximately equal to the linear superposition of their independent impacts. This means that during EQBO phases, the stratospheric ozone anomalies are increased during El Niño events but reduced during La Niña events, and vice versa during WQBO phases. Numerical sensitivity experiments are performed to further investigate the independent and joint influences of EP ENSO and QBO on stratospheric ozone in the NH during winter. The results from simulations agree well with the results from statistical analysis. [ABSTRACT FROM AUTHOR]

Background: The status of axillary lymph nodes (ALNs) is one of the important factors in decision‐making for breast cancer treatment. Physical examination (PE) has long been the main, or even the only, means of clinical staging for ALNs in breast cancer. However, the sensitivity and accuracy of PE remains unsatisfactory. The results from this study suggest that axillary ultrasonography (US) should replace PE as a standard method for the clinical staging of ALNs in breast cancer. Methods: Consecutive and nonselective breast cancer patients treated between September 2018 and November 2018 in our center were enrolled in the study. Comparisons of ALN results between PE/US and pathological results were conducted and the difference in sensitivity, specificity and accuracy between PE and US were tested by McNemar chi‐square test. Results: A total of 123 patients were enrolled into the study. Their ages ranged from 28 to 76 years with a median age of 53 ± 10. There were 83 ALN positive cases and 40 ALN negative cases confirmed pathologically. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of PE and US were 54.2%, 90.0%, 65.9%, 91.8%, 48.7% versus 86.8%, 72.5%, 82.1%, 86.8%, 72.5%, respectively. The sensitivity and accuracy of US was significantly higher than that of PE (P = 0.004 and P = 0.002). Conclusion: The results of this study demonstrated that US is superior in evaluating ALNs when compared with PE and that US should replace PE as the standard method for the clinical staging of ALNs in breast cancer. [ABSTRACT FROM AUTHOR]

Cuticular wax covering the leaf surface plays important roles in protecting plants from biotic and abiotic stresses. Understanding the way in which plant leaf cuticles reflect their growing environment could give an insight into plant resilience to future climate change. Here, we analyzed the variations of cuticular waxes among 59 populations of Leymus chinensis in a common garden experiment, aiming to verify how environmental conditions influence the chemical profiles of cuticular waxes. In total, eight cuticular wax classes were identified, including fatty acids, aldehydes, primary alcohols, alkanes, secondary alcohols, ketones, β‐diketones, and alkylresorcinols, with β‐diketones the predominant compounds in all populations (averaged 67.36% across all populations). Great intraspecific trait variations (ITV) were observed for total wax coverage, wax compositions, and the relative abundance of homologues within each wax class. Cluster analysis based on wax characteristics could separate 59 populations into different clades. However, the populations could not be separated according to their original longitudes, latitudes, annual temperature, or annual precipitation. Redundancy analysis showed that latitude, arid index, and the precipitation from June to August were the most important parameters contributing to the variations of the amount of total wax coverage and wax composition and the relative abundance of wax classes. Pearson's correlation analysis further indicated that the relative abundance of wax classes, homologues in each wax class, and even isomers of certain compound differed in their responses to environmental factors. These results suggested that wax deposition patterns of L. chinensis populations formed during adaptations to their long‐term growing environments could inherit in their progenies and exhibit such inheritance even these progenies were exported to new environments. [ABSTRACT FROM AUTHOR]

Background: Taxane‐based chemotherapy is widely used in lung cancer. ABCB1 have a role in the prediction of treatment response and toxicity of chemotherapy in solid tumors. In this retrospective study, we investigated ABCB1 polymorphism on response and toxicity in taxane‐based chemotherapy in lung cancer patients. Methods: A total of 122 lung cancer patients who received taxane‐based chemotherapy were included in this study. Fluorescence in situ hybridization (FISH) was used for ABCB1 polymorphism detection. Turbidimetric inhibition immunoassay was used for pharmacokinetic analysis. Statistical analysis was performed using SPSS 20.0. Results: The frequency of the ABCB1 2677 site TT/TG/GG genotype was 32.8%, 43.4% and 23.8%, respectively and the frequency of the 3435 sites the TT/TC/CC genotype was 13.9%, 44.3% and 41.8%, respectively. The occurrence of neurotoxicity was higher in patients who had ABCB1 3435 site mutation (TT 88.2%, TC 22.2%, CC 21.6% P = 0.004). There was no significant difference between ABCB1 genotypes with regard to other chemotherapy‐induced toxicity. For non‐small cell lung cancer (NSCLC) patients, those harboring ABCB1 2677 and 3435 site wild‐type patients had longer median progression‐free survival (PFS) in the paclitaxel subgroup (3435 site: TT 3.87 vs. TC 9.50 vs. CC 14.13 months; P < 0.001; 2677 site: TT 4.37 vs. TG 9.73 vs. GG 12.1 months; P = 0.013). The area under the concentration‐time curve (AUC) of 20 patients treated with docetaxel increased for ABCB1 mutation subgroups. Conclusion: ABCB1 mutation is associated with higher neurotoxicity of taxane‐based chemotherapy. It also predicts shorter PFS for NSCLC in paclitaxel‐based treatment. [ABSTRACT FROM AUTHOR]

The mesomorphic isotactic polypropylene was prepared by rapid compression instead of the common method of temperature quenching, and their phase transition under high pressure was investigated in depth by combining wide‐angle X‐ray diffraction, small‐angle X‐ray scattering, and differential scanning calorimetry techniques. It was found that annealing under pressure can promote the further arrangement of chain segments of the mesophase toward the crossed state in the orthorhombic γ‐phase, and the long period of the mesophase slightly decreased from 8.2 to 7.2 nm. The kinetics of this meso‐γ transition strongly depends on pressure. As annealing pressure increased, the mobility of molecular segments was reduced, and then the onset and finishing time of phase transition were both delayed significantly. A critical annealing pressure was found between 1.6 and 1.75 GPa, which determines whether the phase transition occurs or not. When pressure reaches 1.75 GPa, mesophase did not transform at all within 120 min. Based on the results, a reasonable mechanism was proposed to show the crystallization process of mesophase under high‐pressure annealing. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019, 57, 651–661 [ABSTRACT FROM AUTHOR]

Abstract: Oxidative stress and inflammation are critically implicated in ambient fine particulate matter (mean diameter < 2.5 μm; PM2.5)‐induced lung injury. Autophagy, playing a crucial role in various physiopathological conditions, modulates cellular homeostasis and stress adaptation. Resveratrol is a phytoalexin that exerts potent antioxidant effects on cardiopulmonary diseases. To date, the mechanisms by which resveratrol protects against PM2.5 remain to be elucidated. In the present study, we investigated the effect of resveratrol on PM2.5‐induced oxidative injury. The potential role of nuclear factor erythroid‐2‐related factor 2 and autophagy in this progress was explored. Human bronchial epithelial cells were treated with PM2.5 and the cytotoxicity and oxidative stress markers were determined. The results showed that PM2.5 decreased cell viability and elevated the level of lactate dehydrogenase. The levels of malondialdehyde and reactive oxygen species were increased by PM2.5 exposure. PM2.5 also induced a significant increase of the inflammatory cytokines including interleukin (IL)‐6, IL‐8, IL‐1β and tumor necrosis factor α. Meanwhile, PM2.5 triggered autophagy formation and alteration of the nuclear factor erythroid‐2‐related factor 2 pathway. Furthermore, human bronchial epithelial cells were co‐treated with PM2.5 and resveratrol in the presence or absence of 3‐methylamphetamine, an inhibitor of autophagic formation. It was revealed that resveratrol intervention abolished PM2.5‐induced oxidative injury partially through the suppression of autophagy deregulation. Findings from this study could provide new insights into the molecular mechanisms of pulmonary intervention during PM2.5 exposure. [ABSTRACT FROM AUTHOR]

Abstract: A valine carbamate prodrug of daidzein was synthesized to improve its bioavailability because of the poor solubility and low permeability of daidzein. To evaluate the pharmacokinetic behavior of the prodrug, a sensitive and high‐throughput method was developed and validated for the simultaneous determination of daidzein and its prodrug in rat plasma. The samples were extracted by ethyl acetate and then analyzed by a supercritical fluid chromatography with electrospray ionization tandem mass spectrometry method. The separation was achieved by an ACQUITY UPC2™ BEH 2‐EP column maintained at 40°C using carbon dioxide (≥99.99%) and methanol within 3.0 min by gradient elution. The mass transition ion pairs were m/z 254.8→136.7, 398.0→254.9, and 271.0→91.07 for daidzein, the prodrug, and genistein, respectively. The calibration curves were linear over the concentration ranges of 2–500 (r > 0.997) and 10.0–5000.0 ng/mL (r > 0.996) with lower limits of quantification of 2 and 10 ng/mL for daidzein and the prodrug, respectively. The intra‐ and interday accuracy and precision were within ±15% for all quality control samples. This developed method enabled high specificity, low cost, low solvent consumption, and a brief analysis time and was successfully applied to a bioavailability evaluation of daidzein and its carbamate prodrug. [ABSTRACT FROM AUTHOR]

Lactic acid bacteria are of interest to the food industry due to their antimicrobial properties. In this study, five strains of Lactobacillus plantarum were isolated from traditional fermented dairy food in Inner Mongolia; the strains displayed antifungal characteristics. Lactobacillus plantarum ALAC‐4 was selected for further study due to its strong inhibitory effect on fungal development. The antifungal substances produced by L. plantarum ALAC‐4 were characterised based on treatments with heat, pH and enzymes. The antifungal metabolites were analysed using gel‐filtration chromatography and SDS‐PAGE. The results showed that the antifungal substances were heat stable and active against most of the tested fungi, and maximal activity was observed at pH values from 4.0 to 4.5. The antifungal activity was decreased by protease treatments, which indicated the proteinaceous nature of the antifungal substances. Enhanced antifungal activity occurred after 28 h of incubation in de Man, Rogosa, Sharpe (MRS) broth with a 4% inoculum level at 34 °C and initial pH of 7.0, which resulted in an increase from baseline data. The molecular mass of the antifungal substance determined by SDS‐PAGE was approximately 40.32 kDa. This study demonstrated that L. plantarum ALAC‐4 produces a peptide with a remarkable antifungal activity, which can be potentially used as a biopreservative in dairy products. [ABSTRACT FROM AUTHOR]

Systematic characterization of genetic and molecular mechanisms in the formation of hybrid sterility is of fundamental importance in understanding reproductive isolation and speciation. Using ultra-high-density genetic maps, 43 single-locus quantitative trait loci ( QTLs) and 223 digenic interactions for embryo-sac, pollen, and spikelet fertility are depicted from three crosses between representative varieties of japonica and two varietal groups of indica, which provide an extensive archive for investigating the genetic basis of reproductive isolation in rice. Ten newly detected single-locus QTLs for inter- and intra-subspecific fertility are identified. Three loci for embryo-sac fertility are detected in both Nip × ZS97 and Nip × MH63 crosses, whereas QTLs for pollen fertility are not in common between the two crosses thus leading to fertility variation. Five loci responsible for fertility and segregation distortion are observed in the ZS97 × MH63 cross. The importance of two-locus interactions on fertility are quantified in the whole genome, which identify that three types of interaction contribute to fertility reduction in the hybrid. These results construct the genetic architecture with respect to various forms of reproductive barriers in rice, which have significant implications in utilization of inter-subspecific heterosis along with improvement in the fertility of indica-indica hybrids at single- and multi-locus level. [ABSTRACT FROM AUTHOR]

Tobacco smoke is a major risk factor for hepatic cancer. Epithelial-mesenchymal transition (EMT) induced by tobacco smoke is crucially involved in the initiation and development of cancer. Mitogen-activated protein kinase (MAPK) pathways play important roles in tobacco smoke-associated carcinogenesis including EMT process. The chemopreventive effect of curcumin supplementation against cancers has been reported. In this study, we investigated the effects of tobacco smoke on MAPK pathway activation and EMT alterations, and then the preventive effect of curcumin was examined in the liver of BALB/c mice. Our results indicated that exposure of mice to tobacco smoke for 12 weeks led to activation of ERK1/2, JNK, p38 and ERK5 pathways as well as activator protein-1 (AP-1) proteins in liver tissue. Exposure of mice to tobacco smoke reduced the hepatic mRNA and protein expression of the epithelial markers, while the hepatic mRNA and protein levels of the mesenchymal markers were increased. Treatment of curcumin effectively attenuated tobacco smoke-induced activation of ERK1/2 and JNK MAPK pathways, AP-1 proteins and EMT alterations in the mice liver. Our data suggested the protective effect of curcumin in tobacco smoke-triggered MAPK pathway activation and EMT in the liver of BALB/c mice, thus providing new insights into the chemoprevention of tobacco smoke-associated hepatic cancer. Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Solid dispersion technology was used to improve the bioavailability of probucol due to its low hydrophilicity and high lipophilicity. In this study, a highly rapid and sensitive supercritical fluid chromatography with tandem mass spectrometry method was optimized and validated for the determination of probucol in beagle dog plasma with diazepam as an internal standard. The analyte and internal standard were extracted by acetone and then separated on a polar 2-ethylpyridine phase column (100 mm × 3 mm, 1.7 μm) at a flow rate of 1.0 mL/min using CO2 (≥99.99%) and methanol (95:5, v/v) as the mobile phase. The mass transition ion-pair was m/ z 515.6→236.2 and 285.2→193.1 for probucol and internal standard, respectively. Excellent linearity was observed over the concentration range of 5-5000 ng/mL ( r2 ≥ 0.9999) with a lower limit of quantification of 5 ng/mL. The intra- and inter-day accuracy and precision for all quality control samples were within ±15%. The proposed method was accurate, rapid and reproducible, which was successfully applied to a bioavailabilty evaluation of probucol solid dispersion tablets. [ABSTRACT FROM AUTHOR]

The remodeling of cardiac gap junctions contributes to various arrhythmias in a diabetic heart. We previously reported that Epigallocatechin-3-gallate (EGCG) attenuated connexin43 (Cx43) protein downregulation induced by high glucose (HG) in neonatal rat cardiomyocytes, but Cx43 mRNA expression was not affected. It indicated the possible mechanisms of post-transcriptional regulation, which still remains unclear. As microRNAs (miRNAs) regulate gene expression widely at post-transcriptional level, we measured miR-1/206 in cardiomyocytes treated with HG and EGCG by quantitative RT-PCR and investigated their relationship with signal transduction pathways. The results showed that HG induced miR-1/206 elevation by PKC MAPK pathway. Moreover, we tested the negative regulation effect of miR-1/206 on Cx43 protein by miRNAs transfection. EGCG, however, nearly abolished the HG-induced miR-1 augmentation via P38 MAPK pathway. Therefore, our study suggested that PKC-activated miR-1/206 expression might contribute to Cx43 downregulation in HG-treated cardiomyocytes, and EGCG conferred protective effect by inhibiting miR-1 elevation via P38 MAPK pathway. [ABSTRACT FROM AUTHOR]

Supercritical fluid chromatography with tandem mass spectrometry was used to comprehensively profile polyene phosphatidyl choline (PPC) extracted from soybean. We achieved an efficient chromatographic analysis using a BEH-2EP column (3 × 100 mm2, 1.7 μm) with a mobile phase consisting of CO2 and a cosolvent in gradient combination at a flow rate of 1.0 mL/min. The cosolvent consisted of methanol, acetonitrile, and water (containing 10 mM ammonium acetate and 0.2% formic acid). The total single-run time was 7 min. We used this method to accurately detect ten different phospholipids (PLs) during extraction. The limits of quantification for phosphatidyl choline, lyso-phosphatidylcholine (LPC), phosphatidic acid (PA), sphingomyelin, phosphatidyl glycerol, phosphatidyl inositol (PI), cholesterol, cardiolipin, phosphatidyl serine, and phosphatidyl ethanolamine (PE) were 20.6, 19.52, 1.21, 2.38, 0.50, 2.28, 54.3, 0.60, 0.65, and 4.85 ng/mL, respectively. However, adopting the high-performance liquid chromatography with evaporative light scattering detection method issued by the China Food and Drug Administration, only PA, LPC, PE, PI, and PPC could be analyzed accurately, and the limits of quantification were 33.89, 60.5, 30.3, 10.9, and 61.79 μg/mL, respectively. The total single-run time was at the least 20 min. Consequently, the supercritical fluid chromatography with tandem mass spectrometry method was more suitable for the analysis of related PLs. [ABSTRACT FROM AUTHOR]

Tobacco smoke (TS) has been shown to cause gastric cancer. Epithelial-mesenchymal transition (EMT) is a crucial pathophysiological process in cancer development. Mitogen-activated protein kinase (MAPK) pathways play central roles in tumorigenesis including EMT process. Curcumin is a promising chemopreventive agent for several types of cancers. In the present study, we investigated the effects of TS on MAPK pathway activation and EMT alterations in the stomach of mice, and the preventive effect of curcumin was further examined. Results showed that exposure of mice to TS for 12 weeks resulted in activation of extracellular regulated protein kinases 1 and 2 (ERK1/2), the Jun N-terminal kinase (JNK), p38, and ERK5 MAPK pathways as well as activator protein 1 (AP-1) proteins in stomach. TS reduced the mRNA and protein expression levels of the epithelial markers E-cadherin and ZO-1, while the mRNA and protein expression levels of the mesenchymal markers vimentin and N-cadherin were increased. Treatment of curcumin effectively abrogated TS-triggered gastric activation of ERK1/2 and JNK MAPK pathways, AP-1 proteins, and EMT alterations. These results suggest for the first time the protective effects of curcumin in long-term TS exposure-induced gastric MAPK activation and EMT, thus providing new insights into the pathogenesis and chemoprevention of TS-associated gastric cancer. [ABSTRACT FROM AUTHOR]

A high-throughput, rapid, sensitive, environmentally friendly, and economical supercritical fluid chromatography with triple quadruple mass spectrometry method was established and validated for the first time to determine a cerebral stroke treatment drug named 3- n-butylphthalide in dog plasma. Plasma samples were prepared by protein precipitation with methanol and the analytes were eluted on an ACQUITY UPC2TM HSS-C18 SB column (3 × 100 mm, 1.8 μm) maintained at 50°C. The mobile phase comprised supercritical carbon dioxide/methanol (90:10, v/v) at a flow rate of 1.5 mL/min, the compensation solvent was methanol at a flow rate of 0.2 mL/min and the total run time was 1.5 min per sample. The detection was carried out on a tandem mass spectrometer with an electrospray ionization source. Calibration curves were linear over the concentration range of 1.02-1021.00 ng/mL ( r2 ≥ 0.993) with the lower limit of quantification of 1.02 ng/mL. The intra- and inter-day precision values were below 15% and the accuracy was from 97.90 to 103.70% at all quality control levels. The method was suitable for a pharmacokinetic study of 3- n-butylphthalide in beagle dogs. [ABSTRACT FROM AUTHOR]

Breast cancer is the most common cancer in women. Bisphenol A (BPA), as a known endocrine disrupter, is closely related to the development of breast cancer. Curcumin has been clinically used in chemopreventation and treatment of cancer; however, it remains unknown whether microRNAs are involved in curcumin-mediated protection from BPA-associated promotive effects on breast cancer. In the present study, we showed that BPA exhibited estrogenic activity by increasing the proliferation of estrogen-receptor-positive MCF-7 human breast cancer cells and triggering transition of the cells from G1 to S phase. Curcumin inhibited the proliferative effects of BPA on MCF-7 cells. Meanwhile, BPA-induced upregulation of oncogenic miR-19a and miR-19b, and the dysregulated expression of miR-19-related downstream proteins, including PTEN, p-AKT, p-MDM2, p53, and proliferating cell nuclear antigen, were reversed by curcumin. Furthermore, the important role of miR-19 in BPA-mediated MCF-7 cell proliferation was also illustrated. These results suggest for the first time that curcumin modulates miR-19/PTEN/AKT/p53 axis to exhibit its protective effects against BPA-associated breast cancer promotion. Findings from this study could provide new insights into the molecular mechanisms by which BPA exerts its breast-cancer-promoting effect as well as its target intervention. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Worst‐case end‐to‐end delay analysis is important for real‐time applications of switched Ethernet network. The Trajectory approach is one of the mature tools for worst‐case delay analysis to calculate the upper bound of delay. The delay analysis based on the Trajectory approach as well as the packet serialisation of such networks is presented. An optimisation of packet serialisation is proposed in order to improve the Trajectory approach. A case study is illustrated to compare the improved Trajectory approach with the classical one, and the result shows that the improved Trajectory approach can get tighter upper bound of end‐to‐end delay. [ABSTRACT FROM AUTHOR]

ABSTRACT Connexin 43 (Cx43), a gap junctional protein, regulates osteocyte viability, and modulates mechanical stimulation-induced bone remodeling. However, the underlying mechanisms of its action remain unclear. In the current study, osteocyte-like MLO-Y4 cells were exposed to fluid shear stress (FSS) of 16 (physiological) or 30 (high) dyne/cm2 for the indicated time points. Cx43 gene ( Gja1) was silenced using siRNA or the protein was blocked chemically. The signaling molecules related to osteocyte apoptosis, osteogenesis, or osteoclastogenesis were detected at mRNA or protein levels. The results showed that physiological FSS significantly upregulated Cx43, which further inhibited apoptosis pathways (e.g., caspase-3) and osteoclastogenesis signaling (e.g., RANKL), but activated osteogenesis signaling (Sost/sclerostin). Suppressing Cx43 gene ( Gja1) by siRNA or chemically blocking gap junction communication enhanced caspase-3, RANKL, and Sost/sclerostin, which could be restored with physiological FSS over 8 h. In addition, high FSS decreased Cx43 expression and adversely affected signaling molecules compared with physiological FSS. The findings indicate the involvement of Cx43 in mechanotransduction of FSS and in the modulation of mechanical loading-related apoptosis, osteogenesis, and osteoclastogenesis of osteocytes. This may provide a cellular and molecular basis for interpreting the biomechanical mechanism of bone absorption and remodeling. © 2013 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 31:1959-1965, 2013 [ABSTRACT FROM AUTHOR]