Research Progress of Small Molecule Fluorescent Probes for Detecting Hypochlorite.

Hypochlorous acid (HOCl) generates from the reaction between hydrogen peroxide and chloride ions via myeloperoxidase (MPO)-mediated in vivo. As very important reactive oxygen species (ROS), hypochlorous acid (HOCl)/hypochlorite (OCl-) play a crucial role in a variety of physiological and pathological processes. However, excessive or misplaced production of HOCl/OCl- can cause variety of tissue damage and human diseases. Therefore, rapid, sensitive, and selective detection of OCl- is very important. In recent years, the fluorescent probe method for detecting hypochlorous acid has been developed rapidly due to its simple operation, low toxicity, high sensitivity, and high selectivity. In this review, the progress of recently discovered fluorescent probes for the detection of hypochlorous acid was summarized with the aim to provide useful information for further design of better fluorescent probes.

[Synthesis and Luminescence Properties of BiOCL: Dy3⁺Phosphors for NUV Excited White Light-Emitting Diodes].

Abstract In the present paper, we reported the luminescence properties of BiOCl:Dy(3+) and BiOCl:Dy(3+), Li+ phosphor synthesized by conventional solid state method. X-ray diffraction (XRD) and excitation and emission spectroscopy were used to characterize the samples. Results show that pure tetragonal BiOCl:Dy(3+) crystals can be synthesized successfully at 500 °C, and Li+ ion dopant improves the crystallinity of samples furtherly. Under near UV light excitation, the samples,give the characteristic luminescence of Dy(3+) ions located at 478 (blue) and 574 nm (yellow), which show a low yellow-to-blue intensity ratio (Y/B) of Dy(3+) emission and white light emission. Moreover, codoping of Li+ ion can realize the enhancement of emission intensity and the adjustment of emission color. The characteristics of BiOCl:Dy(3+) phosphor, low temperature preparation, good near ultraviolet excitation and white light emission make it to a promising near-ultraviolet WLED phosphor.

Docetaxel modulates the delayed rectifier potassium current (IK) and ATP-sensitive potassium current (IKATP) in human breast cancer cells.

Ion channel expression and activity may be affected during tumor development and cancer growth. Activation of potassium (K(+)) channels in human breast cancer cells is reported to be involved in cell cycle progression. In this study, we investigated the effects of docetaxel on the delayed rectifier potassium current (I K) and the ATP-sensitive potassium current (I KATP) in two human breast cancer cell lines, MCF-7 and MDA-MB-435S, using the whole-cell patch-clamp technique. Our results show that docetaxel inhibited the I K and I KATP in both cell lines in a dose-dependent manner. Compared with the control at a potential of +60 mV, treatment with docetaxel at doses of 0.1, 1, 5, and 10 µM significantly decreased the I K in MCF-7 cells by 16.1 ± 3.5, 30.2 ± 5.2, 42.5 ± 4.3, and 46.4 ± 9% (n = 5, P < 0.05), respectively and also decreased the I KATP at +50 mV. Similar results were observed in MDA-MB-435S cells. The G-V curves showed no significant changes after treatment of either MCF-7 or MDA-MB-435S cells with 10 µM docetaxel. The datas indicate that the possible mechanisms of I K and I KATP inhibition by docetaxel may be responsible for its effect on the proliferation of human breast cancer cells.

[Preparation and up-conversion luminescence properties of Yb3+/Tm3+ co-doped Sb2O4 powder].

The Sb2O4:Yb3+, Tm3+ up-conversion luminescence powder with excellent physical, chemical stability and relative low phonon energy was synthesized by the high temperature solid-state reaction and its up-conversion luminescence property was investigated. Under the 980 nm excitation, infrared and blue up-conversion emissions centered at 800 and 480 nm were observed, which were assigned to the 1G4-->3H6 and 3H4-->3 He transitions of Tm2+, respectively. The influence of Yb3+ and Tm3+ concentration on the up-conversion emission property was also obtained. The up-conversion luminescence increases with increasing of Yb3+ and Tm3+ concentration. Additionally, the up-conversion luminescence mechanism was discussed based on the dependence of Tm3+ up-conversion luminescence on pump power. It is interesting that two photon excitation processes for blue and infrared emission were observed in the Sb2O04: Yb3+, Tm3+ powder under a 980 nm excitation. Based on the energy level diagram of Tma3 and Yb2+ ions, we think that two photons blue emission is contributed to the cooperation energy transfer between Tm"+ and Yb3+ ions. We believe that the Sbz04 : Yb3 , Tm2+ up-conversion luminescence powder will have potential application for new optical devices in up-conversion color displays, sensors, detection of infrared radiation, and lasers.

MiR-487a resensitizes mitoxantrone (MX)-resistant breast cancer cells (MCF-7/MX) to MX by targeting breast cancer resistance protein (BCRP/ABCG2).

Breast cancer resistance protein (BCRP/ABCG2) specifically transports various chemotherapeutic agents and is involved in the development of multidrug resistance (MDR) in cancer cells. MicroRNAs (miRNAs) can play an important role in modulating the sensitivity of cancer cells to chemotherapeutic agents. Therefore, after confirming that BCRP was increased in the mitoxantrone (MX)-resistant MCF-7 breast cancer cell line MCF-7/MX compared with its parental sensitive MCF-7 cell line, we aimed to explore the miRNAs that regulate BCRP expression and sensitize breast cancer cells to chemotherapeutic agents. In the present study, bioinformatic analysis indicated that miR-487a was one of the miRNAs that could bind to the 3' untranslated region (3'UTR) of BCRP. Quantitative RT-PCR (qRT-PCR) analysis demonstrated that the expression of miR-487a was reduced in MCF-7/MX cells, and a luciferase reporter assay demonstrated that miR-487a directly bound to the 3'UTR of BCRP. Moreover, ectopic miR-487a down-regulated BCRP expression at the mRNA and protein levels, increasing the intracellular accumulation and cytotoxicity of MX in resistant MCF-7/MX breast cancer cells. Meanwhile, inhibition of miR-487a increased BCRP expression at the mRNA and protein levels and induced MX resistance in sensitive MCF-7 breast cancer cells. Furthermore, the reduced expression of BCRP and increased antitumor effects of MX were also detected in MCF-7/MX xenograft tumors treated with the miR-487a agmir. Thus, our results suggested that miR-487a can directly regulate BCRP expression and reverse chemotherapeutic drug resistance in a subset of breast cancers.

[Synthesis and photoluminescence properties of Eu3+, Bi3+ codoped BaZrO3 phosphors].

The BaZrO3 : 0.05Bi, xEu(x = 0, 0.010, 0.025, 0.050) phosphors were prepared by using high-temperature solid-state reaction in reducing atmosphere, and their photoluminescence properties were investigated. The broadband emission peak of Bi3+ and the typical emission peaks of Eu3+ were observed in the BaZrO3 phosphors co-doped with Bi3+ and Eu3+ under 340 nm excitation. It is confirmed that energy transfer occurred between Bi3+ and Eu3+ in the BaZrO3 : Bi, Eu phosphors, and the white light BaZrO3 phosphors can be obtained through the energy transfer between Bi3+ and Eu3+.