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Antimalarial drugs Dihydroartemisinin (DHA) and chloroquine phosphate (CQ) exhibit evident anti-cancer activity, particularly as combination therapy. DHA and CQ combination therapy has been proved to exhibit higher cytotoxic effect in tumor cells and lower toxicity to normal cells than combination of artemisinin derivatives (ARTs) and anticancer chemotherapy drugs. However, different physiochemical properties of DHA and CQ, leading to distinctive in vivo outcomes, considerably limited their synergistic effect in cancer treatment. Herein, we developed a lipid nanoparticle (LNP) for co-delivery of DHA and CQ to inhibit proliferation and metastasis of colorectal cancer. Considering the beneficial effects of acid/reactive oxide species (ROS)-sensitive phospholipids and targeting ligands for colorectal cancer cells, an RGD peptide-modified pH/ROS dual-sensitive LNP loaded with DHA and CQ (RLNP/DC) was prepared. It exhibited optimal cytotoxicity and suppression of invasion and metastasis in HCT116 cells in vitro , attributable to irreversible upregulation of intracellular ROS levels, downregulation of VEGF expression, and upregulation of paxillin expression. A mouse model of orthotopic metastasis of colorectal cancer was established to evaluate anti-proliferation and anti-metastasis effects of RLNP/DC in vivo. Thus, an optimized nanoplatform for DHA and CQ combination therapy was developed in this study that offered potential antitumor efficacy against colorectal cancer. [ABSTRACT FROM AUTHOR]

Estrogen performs an important role in the growth and development of breast cancer. There are at least three major receptors, including estrogen receptor (ER)a and ß, and G protein-coupled receptor 30 (GPR30), which mediate the actions of estrogen through using transcriptional and rapid non-genomic signaling pathways. Flavonoids have been considered candidates for chemopreventive agents in breast cancer. Baicalein, the primary flavonoid derived from the root of Scutellaria baicalensis Georgi, has been reported to exert an anti-estrogenic effect. In the present study, the effects of baicalein on 17ß-estradiol (E2)-induced cell invasion, and matrix metalloproteinase-9 (MMP-9) expression and activation were investigated. Furthermore, its effects were compared with that of the active form of the ER modulator tamoxifen 4-hydroxytamoxifen (OHT) and the GPR30 antagonist G15 in ERa- and GPR30-positive MCF-7 breast cancer cells. The results demonstrated that OHT failed to prevent E2-induced cell invasion, upregulation and proteolytic activity of MMP-9. However, baicalein was able to significantly suppress these E2-induced effects. Furthermore, E2-stimulated invasion, and MMP-9 expression and activation were significantly attenuated following G15 treatment. In addition, baicalein significantly inhibited G-1, a specific GPR30 agonist, induced invasion, and reduced G-1 promoted expression and activity of MMP-9, consistent with effects of G15. The results of the present study suggest that baicalein is a therapeutic candidate for GPR30-positive breast cancer treatment, and besides ERa targeting the GPR30 receptor it may achieve additional therapeutic benefits in breast cancer. [ABSTRACT FROM AUTHOR]

Ginsenoside Rg3, a bioactive constituent isolated from Panax ginseng, exhibits antitumorigenic, antioxidative, antiangiogenic, neuroprotective and other biological activities are associated with the regulation of multiple genes. DNA methylation patterns, particularly those in the promoter region, affect gene expression, and DNA methylation is catalyzed by DNA methylases. However, whether ginsenoside Rg3 affects DNA methylation is unknown. High performance liquid chromatography assay, MspI/HpaII polymerase chain reaction (PCR) and reverse transcription-quantitative PCR were performed to assess DNA methylation. It was demonstrated that 20(S)-ginsenoside Rg3 treatment resulted in increased inhibition of cell growth, compared with treatment with 20(R)-ginsenoside Rg3 in the human HepG2 hepatocarcinoma cell line. It was additionally revealed that treatment with 20(S)-ginsenoside Rg3 reduced global genomic DNA methylation, altered cystosine methylation of the promoter regions of P53, B cell lymphoma 2 and vascular endothelial growth factor, and downregulated the expression of DNA methyltransferase (DNMT) 3a and DNMT3b more than treatment with 20(R)-ginsenoside Rg3 in HepG2 cells. These results revealed that the modulation of DNA methylation may be important in the pharmaceutical activities of ginsenoside Rg3. [ABSTRACT FROM AUTHOR]

The pricing problem of geometric average Asian option under fractional Brownian motion is studied in this paper. The partial differential equation satisfied by the option's value is presented on the basis of no-arbitrage principle and fractional formula. Then by solving the partial differential equation, the pricing formula and call-put parity of the geometric average Asian option with dividend payment and transaction costs are obtained. At last, the influences of Hurst index and maturity on option value are discussed by numerical examples. [ABSTRACT FROM AUTHOR]

An open-winding power conversion system with two conventional six-switch voltage-source converters (VSC) affords operation with a lower volt-ampere (VA) rating of each device for a given power rating, as well as a degree of fault tolerance. The disadvantages of such a configuration include a higher total device VA rating and increased conduction loss as compared to a single Y/Δ-connected VSC. In certain ac-dc applications, such as telecommunications, wind, and aerospace generator drives, it is desired to have regulated input currents and output voltage, but regenerative operation is either not required or prohibited. For such applications, an alternative open-winding power converter is proposed in this paper where half-controlled converter (HCC) is employed at each end of an open-winding structure. The resultant total switch count and total VA rating are reduced by half, compared to using full bridges. Besides, the basic advantages of an open-winding configuration, use of HCCs also guarantees immunity to dc-bus shootthrough and simplifies the gate drive circuit. The total VA rating of the proposed topology is found to be 42% less than a six-switch VSC. The operating principle, control method, and analysis with simulation and experimental results of the proposed topology in both a grid-tied rectifier application and a PM generator application are illustrated in this paper. [ABSTRACT FROM AUTHOR]

Geometric-average Asian option pricing model with monotonous transaction cost rate under fractional Brownian motion was established. The method of partial differential equations was used to solve this model and the analytical expressions of the Asian option value were obtained. The numerical experiments show that Hurst exponent of the fractional Brownian motion and transaction cost rate have a significant impact on the option value. [ABSTRACT FROM AUTHOR]

Titanium wire-based solid phase extraction (SPE) is developed for the analysis of six different polycyclic aromatic hydrocarbons in water samples with coupling with high performance liquid chromatography. The adsorbent is a Ti wire on which TiO2nanotubes are first formed by anodization and then Au nanoparticles and n-octadecanethiol are modified. The surface composition and structure of the adsorbent were characterized in detail using field emission scanning electron microscope and Fourier transform infrared spectroscopy. The main parameters affecting the extraction efficiency, such as the volume of the organic modifier, extraction time, elution solvent, and desorption time were optimized. Good linearities ranging from 0.025 to 30 μg L−1with correlation coefficients (R2) ranging from 0.9964 to 0.9999 and low limits of detection were obtained in spiked water samples. Furthermore, this method was successfully applied in the analysis of real river water samples with recoveries in the range of 75.33–115.83% and relative standard deviations ranging from 4.85 to 10.77%. The developed SPE can be a particularly convenient means of sample pretreatment for environmental water samples. [ABSTRACT FROM AUTHOR]

We have demonstrated a self-staring passively continuous-wave mode-locked diode end-pumped Nd:YLF laser with a semiconductor saturable absorber mirror of single-quantum-well (In0.25Ga0.75As) grown by metal-organic chemical-vapor deposition technique at low temperature. The saturable absorber was used as nonlinear absorber and output coupler simultaneously. Stable pulse duration of 3 ps has been achieved at the repetition rate of 98 MHz. The average output power was 530 mW at 1053 nm under the incident pump power of 10 W, corresponding to the peak power of 1.8 kW and pulse energy of 5.4 nJ. [ABSTRACT FROM AUTHOR]