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Low angle dependence single green polystyrene colloidal crystal films were prepared by vertical deposition method using polystyrene microspheres with size of 380 ± 10 nm as raw material and further modified by adding nano-carbon. Without nano-carbon addition, the film showed various colors with changing the angle of incident light under natural light. With nano-carbon addition, saturation and angle dependence of the polystyrene colloidal crystal film were remarkably improved. With 0.01 wt % nano-carbon addition, since the stray light of other wavelengths other than the band gap light was absorbed by the added nano-carbon, the film showed only green color under different angles of incident light, suggesting that the film had low angle dependence. It is significant in the research of color behavior and is helpful to obtain single color polystyrene colloidal crystal film.

Inverse opal zirconia is useful in many ways because of their ability to combine several chemical and physical properties. In this research, polystyrene template was fabricated by self-assembly method and inverse opal zirconia was prepared by colloidal crystal-templating method. The process of preparation of inverse opal zirconia as well as effects on morphology and phase of as-prepared inverse opal zirconia were studied. The results showed precursor ratio of zirconium acetate and methanol, mass ratio of polystyrene templates and precursor and dipping times had remarkable influence on morphology of inverse opal zirconia. When the precursor ratio was 1:1; the mass ratio was 1:15 and dipped once, much better morphology of inverse opal zirconia was obtained. The mass ratio, sintering temperature and holding time had significant effect on crystallization of zirconia. Pure phase zirconia could be obtained when sintered at 600 oC, holding time was 2h and the mass ratio was 1:1. A distinguished single stop band in the visible region of the spectrum and unique structural color were observed in inverse opal zirconia, which will make this material promising candidate for novel pigment.

Using Bi(NO3)3·5H2O and Si(OC2H5)4 as the starting materials, citric acid and polyethylene glycol (PEG)-6000 as the complexing agents, pure Bi2SiO5 powders with good photocatalytic activity were first prepared at low temperature via Pechini sol–gel method. The effect of calcination temperature on the preparation of pure phase as well as the photocatalytic properties was investigated. The thermal analysis and X-ray diffraction results showed that the crystallization temperature of Bi2SiO5 is about 400 °C and pure sample can be obtained at 550 °C. The infrared spectra indicated the pure Bi2SiO5 samples have an Aurivillius-like structure. Furthermore, the as-prepared Bi2SiO5 exhibited efficient photocatalytic activity in the decomposition of Rhodamine B due to a synergistic effect of adsorption and photocatalysis.

Lithium metatitanate (β-Li 2 TiO 3 ) pebbles were fabricated via the modified indirect wet chemistry method. Effect of varied additives, as polyvinyl alcohol, glycerol, and agar on the properties evolution was investigated. The highest density is obtained by adding 2 wt% (weight percent) polyvinyl alcohol, 3 wt% glycerol, and 3 wt% agar, respectively. β-Li 2 TiO 3 pebbles with relative sintered density of 92.4%T.D. (Theoretical Density), the ratio of the intensity of diffraction peak (002) to that of (−133) of about 2.93, about 1.58 mm in diameter, a better sphericity of 1.02, the particle size of 5–6 μm, and the well-developed surface layered structure are successfully fabricated with 3 wt% glycerol. Glycerol is beneficial to improving the properties by other fabrication method as well.

Metastable Bi2SiO5 phase powders were synthesized successfully by Pechini sol-gel method using a simple starting hydro-alcoholic solution consisting of Bi(NO3)3 · 5H2O, TEOS, citric acid, and PEG-6000. The effects of Bi/Si molar ratio, citric acid, and PEG-6000 on the properties of pure Bi2SiO5 powders were investigated. The crystalline phase and fluorescence properties were characterized. The process of Pechini sol-gel method and the effect of purity on fluorescence properties were studied in this paper. X-ray diffraction results illustrate that single phase of Bi2SiO5 can be obtained at 650°C for 1 h. Furthermore, the maximum fluorescence emission wavelength of the powders is located at 355 nm, which represents the band gap of Bi2SiO5 powders is 3.49 eV.

In breast cancer, metastasis is the main reason for patient mortality. In the present study, we used breast cancer MDA-MB-231 cells and a mouse xenograft model to demonstrate the effect of emodin on the migration, invasion and metastasis of human breast cancer MDA-MB-231 cells and the related mechanisms. In vitro, wound healing and Transwell assays showed that emodin dose-dependently inhibited the migration and invasion of MDA-MB-231 cells. Enzyme-linked immunosorbent assay (ELISA) showed that emodin decreased the secretion of MMP-2 and MMP-9. Western blot analysis showed that emodin downregulated the expression levels of MMP-2, MMP-9, uPA and uPAR as well as p38 inhibitor SB203580 and ERK inhibitor PD980559, even though TIMP-1 and TIMP-2 were not obviously changed in the MDA-MB-231 cells. Furthermore, emodin inhibited the activity of p38 and ERK1/2 in the MDA-MB-231 cells. In vivo, emodin inhibited lung metastasis in mice bearing the breast cancer MDA-MB-231 xenografts with no obvious changes in body weight, liver and kidney functions. These results indicated that emodin inhibited the lung metastasis of human breast cancer in a mouse xenograft model, and inhibited the invasion of MDA-MB-231 cells associated with the downregulation of MMP-2, MMP-9, uPA and uPAR expression as well as decreased activity of p38 and ERK.

Bi2SiO5 is a metastable phase compound and one of the important Bi-based Aurivillius phase oxide semiconductors. Pure Bi2SiO5 powders were synthesized successfully by Pechini sol–gel method. The samples were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, field-emission scanning electron microscopy, transmission electron microscopy, thermal analyzer, FTIR spectrometer, Raman spectrometer, fluorescence spectrophotometer and UV/Vis/NIR spectrophotometer. The mechanism of the reaction process was studied. The structure, the optical and photocatalytic properties of pure samples were investigated. The results show that citric acid, polyethylene glycol, solvents and calcination temperature have important effects on the reaction, and pure Bi2SiO5 can be obtained at 650 °C for 1 h. The as-prepared Bi2SiO5 has a typical Aurivillius-like structure and its bang gap energy is 3.5 eV. The results of degradation of Rhodamine B reveal that pure Bi2SiO5 powders prepared by Pechini sol–gel method possess a synergistic effect of adsorption and photocatalysis, which indicates that the Bi2SiO5 powders can be used as an efficient material for wastewater treatment.

Metastasis is the major cause of death in breast cancer patients. In this study, we investigated the effects of baicalin, a natural compound, on cell migration, invasion and metastasis using human breast cancer MDA-MB-231 cell line as model system. Baicalin not only dose-dependently inhibited MDA-MB-231 cells migration and in vitro invasion, but also suppressed the tumor outgrowth and the pulmonary metastasis of MDA-MB-231 cells in xenograft model. Importantly, treatment of baicalin caused little change in body weight, liver and kidney function of recipient animals. Tumorigenesis-inhibitory effect is likely linked to the capability of baicalin to downregulate metalloproteinase (MMP)-2, MMP-9, urokinase-type plasminogen activator (uPA) and uPA receptor (uPAR) expression in MDA-MB-231 cells. As baicalin blocked p38 mitogen-activated protein kinase (MAPK) activity and treatment of p38MAPK inhibitor SB203580 led to the reduction of MMP-2, MMP-9, uPA and uPAR expressions, we concluded that baicalin suppresses the tumorigenecity of MDA-MB-231 cells by down-regulating MMP-2, MMP-9, uPA and uPAR expressions through the interruption of p38MAPK signaling pathway.

Breast cancer remains the leading cause of cancer-related deaths among women. Owing to high efficiency and low toxic effects, further exploration of natural compounds from Chinese herbal medicine may be an efficient approach for breast cancer drug discovery. In this study, we investigated the effects of evodiamine on the growth and metastasis of MDA-MB-231 human breast cancer cells in vitro and in vivo. In vitro, evodiamine inhibited cell migration and invasion abilities through downregulation of MMP-9, urokinase-type plasminogen activator (uPA) and uPAR expression. Evodiamine-induced G0/G1 arrest and apoptosis were associated with a decrease in Bcl-2, cyclin D1 and cyclin-dependent kinase 6 (CDK6) expression and an increase in Bax and p27Kip1 expression. Moreover, evodiamine regulated p-ERK and p-p38 MAPK expression. Evodiamine-induced apoptosis was enhanced by its combination with the extracellular signal-regulated kinase (ERK) inhibitor PD98059 or the p38 mitogen-activated protein kinase (p38 MAPK) inhibitor SB203580. Evodiamine-inhibited metastasis was partly blocked by combination with PD98059 or SB203580. In vivo, the administration of evodiamine (10 mg/kg) significantly reduced tumor growth and pulmonary metastasis. These results demonstrate that evodiamine possesses antitumor activities via inhibition of cell migration and invasion, arrest of the cell cycle and induction of cell apoptosis in MDA-MB-231 cells.

In this article, Bi2SiO5 powders were prepared by molten salt method. Via uniform experiment, the effects of various technological parameters (sintering temperature, holding time, excessive contents of Bi2O3 by weight, and ratios of salts) on synthesis of Bi2SiO5 powders were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), and thermal analysis. Forming mechanism of sheets was discussed. According to the analysis of XRD and SEM, the sample mainly contains Bi2SiO5 phase when the temperature is 650°C, holding time is 2.5 h, excessive content of Bi2O3 is 5 wt%, and the ratio of salts is 50 wt%. Interface reacting mechanism can be used to explain the coarsening process of bismuth silicate sheets produced in molten salt synthesis. In addition, dissolution–precipitation mechanism also plays an important role in the synthesis of bismuth silicate sheets.

The bismuth silicate powders were prepared by reaction of Bi2O3 and SiO2 as raw materials in KCl-K2CO3, NaCl-Na2CO3, K2CO3-Na2CO3, KCl-NaCl, NaCl-Na2SO4, and KCl-K2SO4 molten salts. Pure Bi12SiO20 powders were synthesized in KCl-K2CO3 flux at 635°C for 1 h, which was lower than that of conventional solid state reaction. X-ray diffraction reveals that the phases of the samples are different in various molten salts. Only Bi12SiO20 phase can be observed in the molten salts with ions. However, a mixture of Bi12SiO20, Bi2SiO5, and Bi4Si3O12 phase are observed in the molten salts without ions. Therefore, the carbonates are not only used as the flux and reaction medium, but also inhibit the formation of other bismuth silicates in the synthesis of Bi12SiO20 powders by molten salt synthesis. The scanning electronic microscopy image indicates that the mechanism of molten salt synthesis in the case of KCl-K2CO3 and NaCl-Na2CO3 are “dissolution-precipitation mechanism.” UV-Vis spectra reveals the absorption edge for ...

In this work, barium titanate (BaTiO3) powders were synthesized via two Pechini sol-gel processes using citric acid and polyethylene glycol-6000 as chelating agents. Attempts had been made to understand the thermal behavior of the polymeric intermediates with the help of thermogravimetry-differential scanning calorimetry (TG-DTG-DSC) thermograms. The structural coordination of as-prepared polymeric intermediates was investigated by Fourier transform infrared (FTIR) analysis. The phase and structure of the powders calcined at different temperatures were characterized by X-ray diffraction (XRD) and field emission scanning electron microscope (FE-SEM). Preparation of the polymeric precursors can influence the mechanism of the BaTiO3 synthesis. The formed intermediate phase BaCO3 appears in gel-2 system, and BaCO3 phase does not disappear at 720°C. The formed intermediate phases of gel-1 differ from that of gel-2. The intermediate phases of gel-1 are anatase TiO2 and rutile TiO2, and the intermediate phase Ba...

Polyaniline nanorods, nanoplates and urchin-like structures have been synthesized successfully by the template-free method of aniline and peroxo–polytungstic acid using ammonium persulphate as the oxidant in aqueous solution. The peroxo–polytungstic acid concentration and reaction temperature play important role in the formation process of polyaniline nanostructures. As the precursor concentration increased to 0.29mol/L, nanorods and urchin structures were obtained. With the decrease of temperature, the amount of PANI nanoplates with radially aligned dendritic surface structures will increase. The radially aligned dendritic surface is probably due to the molecular structures of the dopant, the linear nature of PANI chains and the second nucleation formation.

In this paper, Bismuth silicate (Bi4Si3O12, BSO) powders were prepared by reaction in molten salts (NaCl and KCl) using Bi2O3 and SiO2 powders as raw materials. The effects of salt contents and excessive contents of Bi2O3 and SiO2 were characterized by X-ray diffraction and scanning electron microscopy. The properties of Bi4Si3O12 powders were analyzed via fluorescence spectroscopy. Forming mechanism of platelets was discussed. The experimental results suggest that Bi4Si3O12 powders are produced at 780 °C for 4 h with 40 wt% salts and 5 wt% excessive content of Bi2O3. The peaks of excitation spectrum and emission spectrum for BSO powders are separately located at 266 and 457.6 nm. Compared with crystal materials, the excitation spectrum and emission spectrum of Bi4Si3O12 powders indicate blue shift. Interface reacting mechanism can be used to explain the coarsening process of bismuth silicate platelets produced in molten salt synthesis. In addition, dissolution–precipitation mechanism also plays an important role in the synthesis of bismuth silicate platelets.

Poly (aminohexylaminomethyl/phenyl) silsesquioxane (PAHAMPSQ) microparticles with diameter of 350 nm were synthesized by the hydrolytic condensation of aminohexylaminomethyltriethoxysilane (AHAMTES) and phenyltriethoxysilane (PTES) in the presence of H2O by using tetraethylammonium hydroxide (TEAOH) catalysts. PAHAMPSQ containing both aminohexylaminomethyl and phenyl groups were confirmed from FT-IR, TGA. XRD patterns indicate that a certain ordered structure existed in PAHAMPSQ molecules. Contents of amino of PAHAMPSQ were determined by elemental analysis. SEM images show both granular and flake exist in PAHAMPSQ microparticles. Yield of PAHAMPSQ in different AHAMTES/PETS molar ratios was about 80%. PAHAMPSQ offers the potential utility as building blocks for divers and novel organic/inorganic materials.

Polyaniline/SiO2 composites were prepared by the SiO2 particles whose surface character was modified by succinic acid. The composites were characterized by Fourier transform infrared (FT–IR) spectroscopy, X–ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscope (SEM). The results demonstrated that the thermal stability of PANI had improved.

α-Al2O3platelets were prepared in the interface of Na2O-CaO-SiO2glass induced by Al. The morphology of the platelets was observed by Environmental Scanning Electron Microscopy (ESEM). The platelets are irregularly shaped at 720°C for 30mins and share mean thickness of 200nm. EDS shows that the platelets are rich in Si, reasonably due to the formation of Al-Si eutectic. At 1200°C, the prepared platelets have mean diameters between 400nm and 1000nm, most of which are aggregated and part through intergrowth. The crystals develop from the glass and can form good moistening with the glass matrix.

Hydroxyapatite (HA) was synthesized in presence of 20wt% m-ZrO2by solid state reaction between tricalcium phosphate(TCP) and Ca(OH)2at 1000 °C for 2h. Similarily, Fluorine hydroxyapatite(FA) was synthesized using tricalcium phosphate and calcium fluoride as raw materials at 1000 °Cfor 3h. The as-prepared HA was mixed with 10%,25%,45%,55%,70wt% FA and the mixture was sintered at 1000°C-1400°C for 2h. The main phase and bulk density was measured. The results show that when the relative amount of FA to HA increased, the decomposition of the composite is decreased gradually because of the formation of thermally stable FHA solid solutions. Low temperature would effect the exchange of ionic between FA and HA,while high temperature would impact synthesis of composites, because high temperature would lead to dissolution of HA ,which has to react with FA. Increase the content of HA would be advantage for synthesis FHA-ZrO2composite.

Pure Bi12SiO20powder was successfully prepared by a molten salt method using Bi2O3and SiO2as raw materials and using KCl-K2CO3as flux at 635°C with the heating rate of 5°Cmin-1. The phase composition and microstructure of these products were analyzed by X-ray diffraction and scanning electron microscopy, and the effects of the processing parameters, such as the ratio of Bi2O3/SiO2, calciniation temperature, isothermal time and relative amount of salt, on the composition and particle size were investigated. The results indicated that regardless of changing the ratio of Bi2O3/SiO2, calciniation temperature, isothermal time or relative amount of salt the reaction only yielded Bi12SiO20without Bi2SiO5and Bi4Si3O12. Henceforth, KCl-K2CO3molten salts may be considered as an ideal reaction medium to synthesize pure phase of Bi12SiO20. The particle size of Bi12SiO20phase can be determined by changing the temperature, isothermal time and relative amount of salt.

Mitomycin C (MMC) potently suppresses tumour growth. However, its use is limited by its severe toxicity to the kidney and bone marrow. The purpose of this study is to investigate whether the chemoprevention agent curcumin can reduce MMC-associated side-effects and improve MMC efficacy in a breast cancer xenograft model. We first determined the effectiveness of combined MMC and curcumin to inhibit in vitro cell growth and to regress in vivo tumour outgrowth. We then investigated the mechanisms associated with MMC/curcumin-induced cell death by examining the effect of MMC/curcumin treatment on apoptosis, the activation of caspase-3, 8 and 9 and the expression of bcl-2 and bax. We also evaluated the ability of curcumin to alleviate MMC-associated side-effects by comparing the levels of creatinine/blood urea nitrogen (Cr/BUN) and glutamic oxalacetic transaminase/glutamic pyruvic transaminase (GPT/GOT) in serum between animals receiving MMC alone and MMC/curcumin. Curcumin significantly sensitised MCF-7 and MDA-MB-231 cells to MMC-induced cell death and improved MMC's ability to regress MCF-7 xenograft. MMC and curcumin together synergistically enhanced apoptosis in MCF-7 cells and the apoptosis most likely resulted from both the activation of caspases and modulation of bcl-2/bax expression. Most importantly, the inclusion of curcumin in MMC treatment decreased MMC-caused severe side-effects evidenced by significant improvement in the kidney function. Enhancing the tumoricidal effect of MMC, curcumin greatly reduces MMC-associated severe side-effects. Therefore, the combination treatment of MMC and curcumin may be of significant therapeutic benefit in treating breast cancer.

Hydroxyapatite (HA) doped with 3% Yttria-stabilized 20vol%m-ZrO2composite were synthesized by solid state reaction between tricalcium phosphate (TCP) and Ca(OH)2at various temperature(1000 to 1200°C) for 3h with adding 5~20wt% calcium fluoride (CaF2), respectively. The effects of various amount of CaF2on crystallization characteristics of HA-20vol%ZrO2composite were investigated in details. The results show that when small amount of CaF2was added, the reactions of HA with CaF2occurs, which leads to the formation of fluorapatite (FA). With the increasing of the amount of CaF2, the decomposition of HA to β-TCP decreases gradually and the CaZrO3peaks disappear, while t-ZrO2increases because of the formation of thermally stable FHA solid solutions. When the sintered temperature is above 1100°C and the addition of CaF2is about 10wt%, the main phases are FHA and t-ZrO2with a negligible amount of Ca5P8, which suppress the reaction between HA and ZrO2. From SEM, it can be seen that with 10wt% of CaF2addition, the morphology of the composite powder is a mixture of spherical ZrO2particles embedded within agglomerated HA shaped like a small rod.

Hydroxyapatite (HA) doped with 3%yttria-stabilized 20wt% zirconia (ZrO2) ceramic were developed in order to produce a porous composite biomaterial by integrating the gel-casting technique with polymer sponge method with improved mechanical strength and controllable porous structure. The pore morphology, size, and distribution of the scaffolds were characterized using an electron microscope. The scaffolds prepared have an open, uniform and interconnected porous structure with a pore size of 300~500m. The porosity of the open pores in the scaffold can be controlled by changing HA-ZrO2 composite concentration and it is between 87%~35%. A compressive strength of 12MPa for HA-ZrO2 porous scaffolds with HA-ZrO2 concentration of 55wt% was achieved, which is comparable to that of cortical bone.

Mitomycin C (MMC), a chemotherapeutic agent in breast cancer treatments, inhibits tumor growth through DNA cross-linking and breaking, but it has severe side effects. Here we examined whether and how curcumin reduced the side effects of MMC. We found that combination treatment with MMC and curcumin reduced tumor weight by 70% and 36% compared with saline and curcumin-treated groups, respectively. The combination treatment reduced weight loss and improved kidney function and bone marrow suppression compared with MMC treatment alone. Moreover, the combination treatment inhibited glucose regulatory protein (GRP58)-mediated DNA cross-linking. The combination treatment inhibited GRP58 through the ERK/p38 MAPK pathway. In conclusion, the current study provided evidence that MMC and curcumin combination treatment reduced MMC side effects by inhibiting GRP58-mediated DNA cross-linking through the ERK/p38 MAPK pathway.

SiO2 colloidal spheres were synthesized by Stober method. In order to enhance surface charge of the SiO2 spheres, they were modified with succinic acid. Scanning electron microscope (SEM) shows that the average size of modified SiO2 spheres is 473 nm, and its distribution standard deviation is less than 5%; Fourier-transform infrared spectra (FT-IR) and X-ray photoelectron spectrometer (XPS) results indicate that one end of succinic acid is chemically bonded to the SiO2 spheres through esterification; Zeta potential of the modified SiO2 spheres in water solution is improved from −53.72 to −67.46 mV, and surface charge density of the modified SiO2 spheres is enhanced from 0.19 to 0.94 µC/cm2. SiO2 colloidal crystal was fabricated from aqueous colloidal solution by the vertical deposition method at 40°C and 60% relative humidity. SEM images show that the sample of SiO2 colloidal crystal is face-centered cubic (fcc) structure with its (111) planes parallel to the substrate. Transmission measurement shows the existence of photonic band gap at 1047 nm.

A new copper (II) complex [Cu(dtne)] · (ClO4)2 · CH3CH2OH, where dtne is 1,2-bis(1,4,7-triaza-1-cyclononyl)ethane, was prepared and characterized by X-ray crystallography. The result shows that in the complex the copper (II) adopts an octahedral coordination geometry. The cyclic voltammetry of the complex recorded in aqueous solution indicates a reversible one-electron redox reaction. The activity of dismutation of superoxide ( O 2 - ) of the complex in the riboflavin–methionine–nitro blue tetrazolium assay has been researched.

Numerical modeling on falling of sodiumtetraborate aqueous solution drops as the initiator before the gelation of PVA-TiO2 suspensions was conducted. Effect of time and elevation angle of the PVA-TiO2 suspensions on the falling velocity of the sodiumtetraborate aqueous solution drops was analyzed. An ordinary differential equation was given. Integration of the ordinary differential equation was fulfilled using the fourth-order Runge-Kutta method in Matlab 6.5. From the model, a two-order nonlinear effect of time on the velocity of the drops during falling is determined and the quadratic term -3.408t2 serves as the time dependent air resistance. The component of the falling velocity along the suspensions increases with the increasing of the elevation angle. However, for the component vertical to the suspensions, with elevation angle increasing, it decreases.

Spinach (Spinacia oleracea L. cv. Sunlight) seedlings grown under the NFT system were administered 6 or 12 me·liter-1 K from the onset of the experiment to which nitrate-free solution was added 6 days prior to harvest (Experiment 1) or K solutions were added with the nitrate-free solution simultaneously 6 days before harvest (Experiment 2). At harvest the leaf nitrate, ascorbic acid, potassium concentrations, and the residual mineral concentration in the hydroponic solution were determined. No significant reduction in the yield was observed in Exp. 1 in which plants grown in the NFT system were administered 12 me·liter-1 K from the onset of the trial and supplemented with nitrate-N free solution 6 days before harvest. The leaf-nitrate content decreased significantly in plants adiministered 6 and 12 me·liter-1 K with nitrate-free solution 6 days before harvest. The residual nitrate-N in the nutrient solution decreased by approximately 32% at 12 me·liter-1 K as compared to plants exposed to 6 me·liter-1 K in the supplemental nutrient solution. In Experiment 2, in which plants were supplied with low nitrate concentration and 6 or 12 me·liter-1 K in the same hydroponic solution 6 days before harvest, an economically satisfactory yield was obtained. The leaf-nitrate content decreased significantly by lowering nitrate-N concentration, but no significant difference in the leaf-nitrate content was noted between the N-free and N-plus treatments whether the K concentration was 6 or 12 me·liter-1. However, the nitrate-N level in the nutrient solution decreased by 24% at 12 me·liter-1 as compared with that of the 6 me·liter-1 K in the supplemental solution.

The effect of NO3-N in the additional nutrient solution 6 to 18 days before harvest on the growth, yield, and NO3 content in spinach (Spinacia oleracea L. cv. 'Sunlight') plants was studied.There was no significant difference in top fresh weight and yield between the plants exposed to 6 and 8 me•liter-1 NO3-N for 14 days before iarvest. The NO3 content in plants grown in 6 me•liter-1 NO3-N solution in this period decreased to the critical amount of European standard of 3000ppm NO3 in the autumn crop, whereas residual concentration of NO3-N in the nutrient solution decreased to 24.8ppm and 33.4ppm at 6 and 8 me•liter-1, respectively.Economically satisfactory growth and yield were obtained in the plants grown with 3/4 strength of Enshi-shoho nutrient solution until the appropriate plant size was attained and then they were transferred to a NO3-N-free solution 6 days prior to harvest- ing. The NO3 content in those plants decreased to 700ppm in FW basis, whereas re- sidual concentration of NO3-N in the solution decreased significantly by lengthening the NO3-N starvation period.

Aim: To investigate the efficacy of mitomycin C (MMC) in combination with curcumin in suppressing human breast cancer in vitro and in vivo . Methods: Human breast cancer MCF-7 cells were used. Cell viability was measured using MTT assay. The cell cycle phase was detected with flow cytometric analysis. Cell cycle-associated proteins were examined using Western blot analysis. MCF-7 breast cancer xenografts were established to monitor tumor growth and cell cycle-associated protein expression. Results: Curcumin inhibited MCF-7 breast cancer cell viability in a concentration-dependent manner (IC50 value=40 μmol/L). Similarly, MMC inhibited the cell viability with an IC50 value of 5 μmol/L. Combined treatment of MMC and curcumin showed a synergistic antiproliferative effect. In the presence of curcumin (40 μmol/L), the IC50 value of MMC was reduced to 5 μmol/L. In MCF-7 xenografts, combined administration of curcumin (100 mg/kg) and MMC (1-2 mg/kg) for 4 weeks produced significantly greater inhibition on tumor growth than either treatment alone. The combined treatment resulted in significantly greater G1 arrest than MMC or curcumin alone. Moreover, the cell cycle arrest was associated with inhibition of cyclin D1, cyclin E, cyclin A, cyclin-dependent kinase 2 (CDK2) and CDK4, along with the induction of the cell cycle inhibitor p21 and p27 both in MCF-7 cells and in MCF-7 xenografts. These proteins were regulated through p38 MAPK pathway. Conclusion: The results suggest that the combination of MMC and curcumin inhibits MCF-7 cell proliferation and cell cycle progression in vitro and in vivo via the p38 MAPK pathway.

To examine whether the cell growth inhibitory effect of the combination of baicalin and baicalein is related to apoptosis. Moreover, to determine whether the expression of some apoptosis-related proteins is regulated by the ERK/p38 MAPK pathway.Cell viability was measured using a 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Apoptosis was detected by acridine orange (AO) staining, DNA ladder assay and flow cytometric analysis. Apoptosis-related proteins were observed using Western blot analysis.Compared with baicalin or baicalein alone, the combination treatment of baicalin (50 micromol/L) and baicalein (25 micromol/L) had an anti-proliferative effect in a time-dependent manner. Isobologram analysis demonstrated that the combination treatment had a synergistic effect. Moreover, apoptosis in MCF-7 cells was increased by 12% and 20% with the combination treatment at 24 h and 48 h, respectively. With the combination treatment in MCF-7 cells, cleaved caspase-3 and caspase-9 were observed, and the level of bcl-2 expression was decreased approximately 20% and 40% at 24 h and 48 h, respectively. The expression of bax and p53 were increased about 25% and 15% at 48 h, respectively. Moreover, the activation of caspase-3, -9 and the regulation of bcl-2, bax and p53 were related to ERK /p38 MAPK activation.In this study, apoptosis was enhanced by the combination treatment of baicalin and baicalein, which activated caspases-3 and caspase-9, downregulated the level of bcl-2 and upregulated the level of bax or p53 via the ERK/p38 MAPK pathway.