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This study attempts to explore the function and mechanism of action of rosavin in small-cell lung cancer (SCLC) in vitro. The viability and clone formation of SCLC cells were assessed using cell counting kit-8 and colony formation assays, respectively. Apoptosis and cell cycle were detected using flow cytometry and cell cycle analysis, respectively. Wound healing and transwell assays were performed to evaluate the migration and invasion of SCLC cells. Besides, protein levels of p-ERK, ERK, p-MEK and MEK were determined using Western blot analysis. Rosavin repressed the viability and clone formation of SCLC cells, and promoted apoptosis and G0/G1arrest of SCLC cells. At the same time, rosavin suppressed migration and invasion of SCLC cells. Moreover, protein levels of p-ERK/ERK and p-MEK/MEK were decreased after rosavin addition in SCLC cells. Rosavin impaired malignant behaviors of SCLC cells, which may be associated with inhibition of the MAPK/ERK pathway in vitro.

The viscosity of binary blends containing one crystallizable component has been analyzed. The elastic moduli of these phase-separated blends exhibit extremely interesting discontinuities as a function of the overall sample composition. These abrupt changes cannot be attributed to the volume fraction of the crystallizable polyester-rich domains but rather to the extremely small amount (∼2% polyester) of unusual needle-shaped crystallites in the polyester-poor regions and interactions between domains and matrix. Therefore, the overall mechanical property of the binary blend must be considered in terms of the volume fraction of the polyester-rich domains interconnected by these unusual polyester-poor regions.

The viscosity development associated with the microstructure of various crystallizable polymer blends has been investigated. All binary blends, consisting of crystallizable polyester and noncrystallizable polyether, exhibit liquid/liquid phase-separated structures with polyester-rich and polyester-poor phases. The dispersed domains−continuous matrix morphology was observed in blends with 10−40 wt% polyester, while the 50 wt% polyester blend exhibits bicontinuous morphology. Differential scanning calorimetry and optical microscopy were employed to characterize crystallization features of each phase. “Curve-leaf”-shaped crystallites were formed in the polyester-poor phase in all blends studied. The viscoelastic physical gelation of the phase-separated blends with low polyester content of 10−40 wt% was found to be dominated by crystallization in the polyester-poor phase. The unusually high viscosity of the polyester-poor phase is due to the percolated morphology of “curved leaf”-shaped crystallites.

This article presents a general infrared spectroscopic method that enables the monitoring of the adsorption of surfactants and poly-electrolytes on high surface area silica particles from aqueous solution. The method is based on the use of a ZnSe internal reflection element (IRE) coated with a layer of titania particles. The titania surface is then converted to silica using atomic layer deposition with sequential addition of an amine catalyst, gaseous SiCl4, and water vapor. A minimum of three cycles is needed to produce a surface that mimics silica, as evidenced by the reaction of hexamethyldisilazane and zeta potential measurements. It is shown that the silica-coated titania particles on the ZnSe crystals are stable to flowing aqueous solutions below pH = 8 and can be used to study the dynamics of polymer/surfactant adsorption on silica.

A series of novel polymer–clay nanocomposites, that is, liquid-crystalline copolyester/montmorillonite (MMT) nanocomposites, were synthesized by the intercalation polycondensation of terephthalic acid, p-acetoxy benzoic acid, and 1,2-diacetoxy benzene in the presence of different organically modified montmorillonites (OMt's). The OMt's were prepared by the ion exchange of MMT with octadecylamine hydrochloride, p-aminobenzoic acid hydrochloride, or lysine hydrochloride. X-ray diffraction and transmission electron microscopy studies indicated that the inorganic cations in the MMT interlayers were already exchanged by organic onium ions and that the OMt intercalated with p-aminobenzoic acid or lysine was good for obtaining more delaminated clay nanocomposites. The glass-transition temperature and modulus of the nanocomposites increased compared with those of the pure polymer, whereas the isotropic temperature decreased. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3155–3159, 2003