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Background: Berberine is a promising natural drug that has a potential therapeutic effect on neurodegenerative diseases. Objectives: Using U251 cells in vitro, we investigated whether berberine exerts its neuroprotective effect via regulation of CYP2J2. Method: After pretreatment with increasing concentrations (1, 3, and 10 μmol/L) of berberine for 0.5 h, U251 cells were stimulated with 1 μg/mL of lipopolysaccharide (LPS). Cell viability was measured 24 h later using a CCK8 kit. mRNA and protein levels of CYP2J2 and peroxisome proliferator-activated receptor alpha (PPARα) were measured by quantitative real-time-polymerase chain reaction and western blotting, respectively, after 24 h of exposure to 1, 3, or 10 μmol/L berberine. Fluorescence immunocytochemistry was also used to evaluate PPARα protein expression after treatment of U251 cells with 10-μmol/L berberine for 24 h. Transient transfection (cotransfection with the plasmid of PPARα- and RXRα-containing) followed by luciferase and chromatin immunoprecipitation assays was used to elucidate the molecular mechanism underlying the observed effects. Results: Compared to the control, LPS-induced U251 cell death was attenuated by berberine in a dose-dependent manner. After 24 h, cell viability was found to be 52.3% (p < 0.05), 66.2% (p < 0.01), and 70.9% (p < 0.001) using 1, 3, and 10 μmol/L berberine treatment, respectively. At these concentrations, berberine increased the CYP2J2 mRNA levels by 1.31-fold (p < 0.05), 1.48-fold (p < 0.01), and 1.88-fold (p < 0.01), respectively, and increased the PPARα mRNA levels 1.17-fold (p < 0.05), 1.29-fold (p < 0.05), and 1.53-fold (p < 0.01), respectively, compared with the respective control groups. In addition, the CYP2J2 and PPARα protein level was also significantly upregulated in U251 cells by berberine (concentrations in 1, 3, and 10 μmol/L) in a dose-dependent manner, compared with the respective control groups. Further investigation indicated that berberine enhances the heterodimerization of PPARα and RXRα, which together bind to the CYP2J2 promoter to induce the expression of CYP2J2 in U251 cells. Conclusion: Upon exposure of U251 cells to berberine, CYP2J2 expression is induced as a result of PPARα stimulation, resulting in a neuroprotective effect.

Berberine is a promising natural drug that has a potential therapeutic effect on neurodegenerative diseases.Using U251 cells in vitro, we investigated whether berberine exerts its neuroprotective effect via regulation of CYP2J2.After pretreatment with increasing concentrations (1, 3, and 10 μmol/L) of berberine for 0.5 h, U251 cells were stimulated with 1 μg/mL of lipopolysaccharide (LPS). Cell viability was measured 24 h later using a CCK8 kit. mRNA and protein levels of CYP2J2 and peroxisome proliferator-activated receptor alpha (PPARα) were measured by quantitative real-time-polymerase chain reaction and western blotting, respectively, after 24 h of exposure to 1, 3, or 10 μmol/L berberine. Fluorescence immunocytochemistry was also used to evaluate PPARα protein expression after treatment of U251 cells with 10-μmol/L berberine for 24 h. Transient transfection (cotransfection with the plasmid of PPARα- and RXRα-containing) followed by luciferase and chromatin immunoprecipitation assays was used to elucidate the molecular mechanism underlying the observed effects.Compared to the control, LPS-induced U251 cell death was attenuated by berberine in a dose-dependent manner. After 24 h, cell viability was found to be 52.3% (p0.05), 66.2% (p0.01), and 70.9% (p0.001) using 1, 3, and 10 μmol/L berberine treatment, respectively. At these concentrations, berberine increased the CYP2J2 mRNA levels by 1.31-fold (p0.05), 1.48-fold (p0.01), and 1.88-fold (p0.01), respectively, and increased the PPARα mRNA levels 1.17-fold (p0.05), 1.29-fold (p0.05), and 1.53-fold (p0.01), respectively, compared with the respective control groups. In addition, the CYP2J2 and PPARα protein level was also significantly upregulated in U251 cells by berberine (concentrations in 1, 3, and 10 μmol/L) in a dose-dependent manner, compared with the respective control groups. Further investigation indicated that berberine enhances the heterodimerization of PPARα and RXRα, which together bind to the CYP2J2 promoter to induce the expression of CYP2J2 in U251 cells.Upon exposure of U251 cells to berberine, CYP2J2 expression is induced as a result of PPARα stimulation, resulting in a neuroprotective effect.

Carbon nanotubes (CNTs) based phase change composites have been widely reported to be used in areas related to energy conversion and storage. However, these bulk-like materials are not convenient for the further applications. Herein, we introduce the preparation of electrically conductive CNT/polymer films into the fabrication of conductive PCM films. The stable single wall carbon nanotube (SWCNT) dispersion was prepared by ultrasonic treatment with the help of surfactant. The SWCNT hydrogel was prepared by the addition of CaCl2 (aq.) via colloid aggregation (diffusion-limited cluster aggregation). Eicosane was infiltrated into the SWCNT skeleton by diffusion after solvent replacement, and the flexible phase change film (PCMF) was easily obtained by volatilization synchronously. According to the SEM images, eicosane was encapsulated in the SWCNT scaffolding. And PCMF exhibited a promising conductivity, flexibility, thermal stability and reversibility during the heat storage and release processes. For example, when the SWCNT ratio was 27.1%, the latent heat and conductivity were 204.8 J/g and 620.3 S/m, respectively. The results of 200 repeated melting and freezing cycles revealed that the sample have stable latent heat performance. The eicosane/SWCNT films could store thermal energy at modulated input voltage, which could be applied by conventional batteries. And the highest energy storage efficiency of samples was up to 91.3%. These flexible electro-driven films have wide prospect in smart electronic device, small scale heater, infrared stealth, wearable devices, etc.

A new highly sensitive 1, 8-naphthalimide-based compound (probe 1) has been designed and synthesized. The colorimetric and fluorescent properties of probe 1 towards various amino acids were investigated in detail. Specific colorimetry and fluorescence response of probe 1 for thiols were found in PBS buffer solution, which can be deduced to a reaction of thio-promoted conjugate addition/cyclization sequence between probe 1 and thiols. The probe 1 can selectively recognize cysteine rather than other natural amino acids in aqueous solution with a rapid response time. Con-focal fluorescence imaging of cells for detecting thiols in vivo was carried out successfully.

Two new pentacyclic triterpenes, (3β,21β)-19,21-epoxylup-20(29)-en-3-yl acetate (1) and (3β)-9,18-dihydroxyolean-12-en-3-yl acetate (2), were isolated from Abelmoschus esculentus (L.) Moench. Their structures were determined on the basis of detailed analyses of their 1D- and 2D-NMR-spectroscopic and MS data.

The payload on board the FengYun 3 (FY-3) satellite series has been providing critical observations to the Earth, and the observation data have been processed and distributed to various users by the corresponding ground application system. In this paper, the FY-3 payload and its future development plan are presented, and its ground system is introduced. The major characteristics of the FY-3 instruments and the requirement on the instruments for major applications are discussed as well. There are nine new instruments, including the Microwave Temperature Sounder (MWTS), Microwave Humidity Sounder (MWHS), Infrared Atmospheric Sounder (IRAS), Medium-Resolution Spectral Imager (MERSI), Microwave Radiation Imager (MWRI), Solar Backscatter Ultraviolet Sounder, Total Ozone Unit, Solar Irradiation Monitor, and Earth Radiation Measurement. The data quality from the IRAS, MWTS, MWHS, and MWRI has proved to be good, and according to our evaluation at the European Centre for Medium-Range Weather Forecasts (ECMWF), the data have a very high availability. The MERSI has 20 visible (VIS) and infrared (IR) channels, of which three are VIS channels with a 250-m spatial resolution, one is a near-IR channel with a 250-m spatial resolution, and one is a long-wave IR channel with a 250-m spatial resolution. The global data at a 250-m spatial resolution are very useful in weather, disaster, and environmental monitoring. Compared with the ground observations, the ozone products derived from the FY-3 series are highly accurate. We have completed the calibration and validation of these sensors and most products.

Fengyun 3 series are the second-generation polar-orbiting meteorological satellites of China. The first satellite of Fengyun 3 series, FY-3A, is a research and development satellite with 11 payloads onboard. FY-3A was launched successfully at 11 a.m. on May 27, 2008. Since the launch, FY-3A data have been applied to the services on the flood season and the Beijing 2008 Olympic Games. In this paper, the platform, payloads, and ground segment designs are introduced. Some typical images during the on-orbit commission test are rendered. Improvements of FY-3A on Earth observations are summarized at the end by comparing them with FY-1D, the last satellite of Fengyun 1 series.

A novel water-soluble colorimetric and ratiometric fluorescent probe was synthesized and applied to imaging palladium species under physiological conditions in phosphate buffered saline (PBS) containing less than 1% organic cosolvent without adding any additional reagents. Based on palladium triggered terminal propargyl ethers cleavage reaction, the probe exhibited a high selectivity and sensitivity for palladium species of all the typical oxidation states (0, +2, +4), with a low detection limit (25 nM, 2.7 μg/L) and an obvious color change. Furthermore, the probe was successfully used for ratiometric fluorescence imaging of palladium in living cells.

A merocyanine-based highly selective colorimetric and ratiometric fluorescent probe is described for Cys detection in water and diluted deproteinized human serum. Upon reaction with Cys in aqueous buffer solution, the probe showed a dramatic color change from faint yellow to pink and remarkable ratiometric fluorescence enhancement signals were also observed, which are ascribed to an intramolecular charge transfer (ICT) process. This strategy was based on modulating the merocyanine π-electron system by conjugation and removal of the acrylate group to release the chromophore group, resulting in a specific colorimetry and fluorescence response. The probe has low cytotoxicity and good cell permeability. It is readily employed for assessing the change of the intracellular Cys level.

Magnetic nanoparticles with attractive optical properties have been proposed for applications in such areas as separation and magnetic resonance imaging. In this paper, a simple and novel fluorescent sensor of Zn2+ was designed with 3,5-di-tert-butyl-2-hydroxybenzaldehyde [DTH] covalently grafted onto the surface of magnetic core/shell Fe3O4@SiO2 nanoparticles [NPs] (DTH-Fe3O4@SiO2 NPs) using the silanol hydrolysis approach. The DTH-Fe3O4@SiO2 inorganic-organic hybrid material was characterized by transmission electron microscopy, dynamic light scattering, X-ray power diffraction, diffuse reflectance infrared Fourier transform, UV-visible absorption and emission spectrometry. The compound DTH exhibited fluorescence response towards Zn2+ and Mg2+ ions, but the DTH-Fe3O4@SiO2 NPs only effectively recognized Zn2+ ion by significant fluorescent enhancement in the presence of various ions, which is due to the restriction of the N-C rotation of DTH-Fe3O4@SiO2 NPs and the formation of the rigid plane with conjugation when the DTH-Fe3O4@SiO2 is coordinated with Zn2+. Moreover, this DTH-Fe3O4@SiO2 fluorescent chemosensor also displayed superparamagnetic properties, and thus, it can be recycled by magnetic attraction.