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Background In Korea and China, asiasari radix (AR) is widely used as a traditional anti-inflammatory and analgesic agent. After its skin-regenerating and hair loss-preventing activities were identified, several types of AR extracts were used for aesthetic purposes. Nevertheless, the effect of ARE on various types of skin cancers was not fully studied yet. Methods In this study, we tested the effect of an ethanolic AR extract (ARE) on G361 human melanoma and HaCaT human keratinocyte cell lines. After ARE exposure, cell growth and the expression patterns of proteins and genes were monitored. Results The ARE-mediated cell growth inhibition was greater in G361 cells than in HaCaT cells due to differences in its cell growth regulation effects. Interestingly, ARE treatment induced caspase-3-mediated apoptosis in G361 cells, but not in HaCaT cells. Furthermore, ARE reduced the expression of p53 and p21 proteins in G361 cells, whereas it induced their expression in HaCaT cells. ARE induced cell death in G361 cells through the reactive oxygen species (ROS)-dependent regulation of p53 and p21 in G361 cells. Microarray analysis showed that ARE regulates Mouse double minute 2 homolog (MDM2) and CASP8 and FADD-like apoptosis regulator (CFLAR) gene expression in G361 and HaCaT cells differently. Conclusion The treatment of ARE preferentially induces apoptosis in melanoma cells by the ROS-dependent differential regulation of p53 level. Therefore, ARE can be used as a new medicinal option for melanoma.

Purpose This study was conducted to verify the induction and mechanism of selective apoptosis in G361 melanoma cells using anti-HER2 antibody-conjugated gold nanoparticles (GNP-HER2). Materials and methods Following GNP-HER2 treatment of G361 cells, cell cycle arrest and apoptosis were measured by WST-1 assay, Hemacolor staining, Hoechst staining, immunofluorescence staining, fluorescence-activated cell sorting analysis, and Western blotting. Results G361 cells treated with GNP-HER2 showed condensation of nuclei, which is an apoptotic phenomenon, and translocation of apoptosis-inducing factor and cytochrome c from mitochondria into the nucleus and cytoplasm, respectively. Increases in BAX in cells undergoing apoptosis, activation of caspase-3 and -9, and fragmentation of poly (ADP-ribose) polymerase and DNA fragmentation factor 45 (inhibitor of caspase-activated DNase) were observed upon GNP-HER2 treatment. Following GNP-HER2 treatment, an increase of cells in sub-G1 phase, which is a signal of cell apoptosis, was observed. This resulted in the down-regulation of cyclin A, cyclin D1, cyclin E, cdk2, cdk4, and cdc2 and the up-regulation of p21. Thus, GNP-HER2 treatment was confirmed to induce the cessation of cell cycle progression. Also, decreases in phospho-focal adhesion kinase and phospho-human epidermal growth factor receptor, which activate cellular focal adhesion, and decreases in phospho-paxillin, which stimulates the disassembly of filamentous actin, were observed. Reduced cell adhesion and disassembly of the intracellular structure indicated cell deactivation. Conclusion GNP-HER2 can selectively kill G361 melanoma cells without affecting normal cells. The mechanism of G361 cell death upon treatment with GNP-HER2 was apoptosis accompanied by activation of caspases.

The reactions of tetrakis (μ-2-anilinopyridinato) dirhodium(II, III) chloride, Rh 2 (ap) 4 Cl, with NaR or LiR, where R is the terminal acetylide ion (C≡CH, C≡CC 6 H 5 , C≡CC 5 H 11 , or C≡CC 4 H 8 C≡CH), results in the nucleophilic substitution of the axial chloride with the aliphatic group to form a Rh-C σ bond. The complex Rh 2 (ap) 4 (C≡CH), C 46 H 37 N 8 Rh 2 •CH 2 Cl 2 , crystallizes in the triclinic space group P1

Adsorption and desorption characteristics for mercury ions using aminated chitosan bead which showed very high affinity to mercury ions were studied. The adsorption of mercury ions using aminated chitosan bead was an exothermic process since binding strength each other increased as the temperature decreased. And the adsorption of mercury ions was almost completed in 100 min at 150 rpm. In case that adsorbent dose increased, mercury uptake capacity decreased, while, removal efficiency increased. The beads were not greatly affected by the ionic strength, organic material and alkaline-earth metal ions. Mercury ions adsorbed on aminated chitosan bead were desorbed effectively about 95% by EDTA and the adsorption capacity of the recycled beads can still be maintained at 90% level at the 5th cycle.

The authors recently reported that dioxygen could be catalytically reduced by tetrakis(..mu..-2-anilinopyridinato)dirhodium(II) at an applied potential of -0.48 V in aprotic solvents. In order to extend these studies to aqueous solutions, a working electrode material was needed to disperse the water-insoluble dirhodium catalyst for electrochemical measurements. In this regard, carbon paste has several distinct advantages. In this study, they report the design and characterization of a chemically modified carbon paste electrode with a large geometric surface area that is easy to construct and convenient to use for chronoamperometric studies. The electrode is used to investigate the catalytic reduction of O/sub 2/ in aqueous solution by the electroactive dirhodium complex and allows the easy analysis of the generated H/sub 2/O/sub 2/ in aqueous solution.