Solution and rheological properties of cationic cellulose/gemini surfactant: Effect of the alkyl chain and spacer length.

In this paper, three sulfonate-containing gemini surfactants, sodium 1,1'-(4,4'-methylenebis(4,1-phenylene))bis(1-oxooctane-2-sulfonate) (C8-M1-C8), sodium 1,1'-(4,4'-(ethane-1,2-diyl)bis(4,1-phenylene))bis(1-oxooctane-2-sulfonate) (C8-M2-C8), sodium 1,1'-(4,4'-methylenebis(4,1-phenylene))-bis(1-oxododecane-2-sulfonate) (C12-M2-C12), were synthesized and characterized with FT-IR, 1H NMR and MS. Furthermore, interaction between a cationic cellulose-based polyelectrolyte, PQ-10, and gemini surfactants were investigated by surface tension, turbidity, flow and low-amplitude oscillation rheology analysis. For comparing, the interaction of their corresponding monomeric counterpart sodium dodecyl sulfate (SDS), sodium 1-octanesulfate (SOS) was also studied. Results showed that the concentration value at T1, defined as critical surface complex concentration, for the PQ-10/surfactant was in order of PQ-10/C8-M2-C8> PQ-10/C8-M1-C8 > PQ-10/C12-M2-C12. Precipitation appeared at low concentration for Gemini surfactants than their monomeric counterparts, and for the gemini surfactants with shorter spacer or longer hydrocarbon chain. The increase/decrease of the crossover frequency (ωc) (the relaxation time, τc) for PQ-10/C12-M2-C12 indicated the formation/collapse of network structures, while PQ-10/SDS showed no obvious change.

Aspirin inhibits the proliferation of hepatoma cells through controlling GLUT1-mediated glucose metabolism.

Aspirin can efficiently inhibit liver cancer growth, but the mechanism is poorly understood. In this study, we report that aspirin modulates glucose uptake through downregulating glucose transporter 1 (GLUT1), leading to the inhibition of hepatoma cell proliferation. Our data showed that aspirin significantly decreased the levels of reactive oxygen species (ROS) and glucose consumption in hepatoma cells. Interestingly, we identified that GLUT1 and HIF1α could be decreased by aspirin. Mechanically, we demonstrated that the -1008/-780 region was the regulatory element of transcriptional factor NF-κB in GLUT1 promoter by luciferase report gene assays. PDTC, an inhibitor of NF-κB, could suppress the expression of GLUT1 in HepG2 and H7402 cells, followed by affecting the levels of ROS and glucose consumption. CoCl2-activated HIF1α expression could slightly rescue the GLUT1 expression inhibited by aspirin or PDTC, suggesting that aspirin depressed GLUT1 through targeting NF-κB or NF-κB/HIF1α signaling. Moreover, we found that GLUT1 was highly expressed in clinical HCC tissues relating to their paired adjacent normal tissues. Importantly, we observed that high level of GLUT1 was significantly correlated with the poor relapse-free survival of HCC patients by analysis of public data. Functionally, overexpression of GLUT1 blocked the PDTC-induced or aspirin-induced inhibition of glucose metabolism in HepG2 cells. Conversely, aspirin failed to work when GLUT1 was stably knocked down in the cells. Administration of aspirin could depress the growth of hepatoma cells through controlling GLUT1 in vitro and in vivo. Thus, our finding provides new insights into the mechanism by which aspirin depresses liver cancer.

[Fast Determination of Auramine â ¡, Basic Orange â ¡ and Metanil Yellow in Bean Products on Surface Enhanced Raman Spectroscopy and Use High Pergormance Liquid Chromatography-Tandem Mass Spectrometry to Verify]

This experiment adopts Surface Enhanced Raman Spectroscopy (SERS) to quickly detect auramine Ⅱ, basic orange Ⅱ and metanil yellow in bean products. It uses High Performance Liquid Chromatography (HPLC)-tandem mass spectrometry to verify. The best extraction solvent is methanol-water (Seven plus three) solution. Before classification, extracting the bean products withAccelerated Solvent Extaction (ASE) and purifying it with Gel Permeation Chromatography(GPC), which improves the extraction efficiency, improves the detection sensitivity, reduces the dosage of extraction solvent and effective in the matrix of macromolecular distractors.ASE and GPC conditions are optimized. This study of three types of pigment surface enhanced Raman spectra characteristic peak of the ownership certification. The characteristic peak of auramine Ⅱ, basic orange Ⅱ and metanil yellow is respectively 652, 995 and 983 cm-1; he method detection limit is 3.0, 1.0 and 4.0 mg·kg-1. Three quantitative characteristic peak of pigment had a good linear relationship with pigment concentration，Recovery of this experiment was 83.48%～92.59% range, relative standard deviation less than 7.2%. The method is characterized by simple pretreatment, short analysis period and high sensitivity, etc. The method provides a reliable reference for food pigment detection.