Characterization of Powder Cosmetics Based on Friction Dynamics.

Frictional properties are one of the most important physical factors in the design of powder cosmetics. In this study, 21 powder cosmetics were applied to artificial skin, and their friction characteristics were evaluated using a sinusoidal motion friction evaluation system. Three friction profiles were observed that depended on the sliding velocity. Principal component analysis showed that the principal component (Z), which characterized the friction dynamics of powder cosmetics, included the static friction coefficient (µ s), the kinetic friction coefficient (µ k), the delay time (δ), and the viscosity coefficient (C). Furthermore, a cluster analysis on Z suggested that powder cosmetics can be classified into three groups according to their friction dynamics. These results may be helpful to understand the phenomena that occur during the application of powder cosmetics.

Characterization of Cosmetic Dispersions Based on Friction Dynamics.

Frictional properties are one of the most important physical factors in the design of cosmetic dispersions in which solid particles are dispersed in a liquid. The effects of ingredients and formulations on frictional properties have been previously reported. In this study, the frictional properties of 33 cosmetic dispersions were evaluated using a sinusoidal motion friction evaluation system when applied on an artificial skin. A detailed analysis of the velocity dependence of the friction coefficient demonstrated that all cosmetic dispersions exhibited stable pattern and the friction behavior did not change during the round trip. We analyzed friction-based parameters by principal component analysis and demonstrated that the principal components Z 1 and Z 2 include the static friction coefficient µ s, kinetic friction coefficient µ k, delay time δ, and viscosity coefficient C, and that these factors are involved in characterizing friction dynamics. The cluster analysis on Z 1 and Z 2 suggested that these dispersions can be classified in three groups with respect to friction dynamics. These results can help understand the characteristics of cosmetics and control their function and utility.

Photothermal ablation cancer therapy using homogeneous CsxWO3 nanorods with broad near-infra-red absorption.

Recently, photothermal ablation therapy (PTA) employing near-infrared radiation (NIR) has been extensively investigated as an emerging modality for cancer management. However, the clinical translation of this promising approach is limited by the lack of PTA agents with broad NIR absorption, low cost and high photothermal conversion efficiency. Herein, we have developed PEGylated homogeneous CsxWO3 nanorods (a mean size ∼69.3 nm × 12.8 nm) with broad photo-absorption (780-2500 nm) as a novel NIR absorbent for PTA treatment of human cancer. The prepared CsxWO3 nanocrystals displayed strong near-infrared optical absorption with a high molar extinction coefficient (e.g. 4.8 × 10(10) M(-1) cm(-1) at 980 nm), thus generated significant amounts of heat upon excitation with near-infrared light. The PTA study in two human carcinoma cell lines (i.e. A549 lung cancer cells and HeLa ovarian cancer cells) demonstrated that CsxWO3 nanorods can efficiently cause cell death via hyperthermia induced lysosome destruction, cytoskeleton protein degradation, DNA damage and thereafter cellular necrosis or apoptosis. Our study also confirmed the migration of healthy cells migrated from unirradiated areas to dead cell cycle, which is essential for tissue reconstruction and wound healing after photodestruction of tumor tissue. The prompted results reported in the current study imply the promising potential of CsxWO3 nanorods for application in PTA cancer therapy.

Synthesis of new glycosides by transglycosylation of N-acetylhexosaminidase from Serratia marcescens YS-1.

Serratia marcescens YS-1, a chitin-degrading microorganism, produced mainly N-acetylhexosaminidase. The purified enzyme had an optimal pH of approximately 8-9 and remained stable at 40 degrees C for 60 min at pH 6-8. The optimum temperature was around 50 degrees C, and enzyme activity was relatively stable below 50 degrees C. YS-1 N-acetylhexosaminidase hydrolyzed p-nitrophenyl beta-N-acetylgalactosamide by 28.1% relative to p-nitrophenyl beta-N-acetylglucosamide. The N-acetylchitooligosaccharides were hydrolyzed more rapidly, but the cellobiose and chitobiose of disaccharides that had the same beta-1,4 glycosidic bond as di-N-acetylchitobiose were not hydrolyzed. YS-1 N-acetylhexosaminidase efficiently transferred the N-acetylglucosamine residue from di-N-acetylchitobiose (substrate) to alcohols (acceptor). The ratio of transfer to methanol increased to 86% in a reaction with 32% methanol. N-Acetylglucosamine was transferred to the hydroxyl group at C1 of monoalcohols. A dialcohol was used as an acceptor when the carbon number was more than 4 and a hydroxyl group existed on each of the two outside carbons. Sugar alcohols with hydroxyl groups in all carbon positions were not proper acceptors.