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Diabetes nephropathy (DN) is the most common microvascular complications of diabetes, as hyperglycemia induces mesangial cell (MC) proliferation and inflammation and subsequently contributes to the development of renal fibrosis. Sphingosine kinase 1 (SphK1)/sphingosine 1-phosphate receptor 2 (S1P2) signaling pathway could activate AP-1 and NF-κB, which played a key regulatory role in the pathological progression of DN. This study investigates whether resveratrol (RSV) plays a regulatory role by SphK1/S1P2 pathway in MCs proliferation and inflammation under high glucose condition. Herein, we found that RSV inhibited MCs proliferation and attenuated high glucose (HG)-induced FN, TGF-β1, ICAM-1, iNOS, SphK1 and S1P2 expression and inhibited SphK1 activity andS1P production, which was also in accordance with MCs transfected with wild-type SphK1WT plasmid. Furthermore, RSV remarkably reduced AP-1 and NF-κB activation. Overall, these results indicated that RSV could be a potential and valuable resource of natural compounds for DN treatment via SphK1/S1P2 pathway.

A solid-phase microextraction fiber (SPME) was synthesized for pre-concentration of 15 phthalates from aqueous samples. Graphene oxide was immobilized on Ti wire with titanol groups using a cross-linking agent and subsequently reduced to yield a folded and wrinkled graphene coating. This graphene-Ti fiber demonstrated durable mechanical robustness and enhanced stability for more than 200 extraction cycles due to the Ti substrate and chemical bond. The extraction efficiencies reached highest when the graphene layers were four and their performances were superior to commercial SPME fibers. The prepared fiber was used for pre-concentration of phthalates from aqueous samples by direct immersion extraction and thermal desorption for gas chromatography–mass spectrometry analysis. The method was utilized for the simultaneous analysis of 15 phthalates with satisfactory recoveries in the range of 82.8–97.8% for bottled water and 73.3–102.0% for intravenous drips in plastic packaging.

The distribution of 15 phthalate acid esters (PAEs) in water, sediment and suspended particle samples from representative lakes of Beijing was investigated and its relationship with anthropogenic activities was also assessed. The sample preparation and analysis methods for PAEs, using solid-phase extraction or microwave assisted extraction coupled with gas chromatography–mass spectrometry, were developed to achieve the satisfactory detection limits and recoveries. The analysis results indicated occurrences of most target PAEs were widespread in the researched lakes with the total PAE concentrations ranged from 0.386 to 3.184 μg/L in water, from 52.6 to 8216.4 ng/g dry weight in sediments and from 138.7 to 2052.4 μg/g dry weight in suspended particles. Di-(2-ethylhexyl) phthalate and di-butyl phthalate were the predominant PAEs, frequently being detected in all matrices, followed by di-iso-butyl phthalate and butyl benzyl phthalate. It was also found that anthropogenic activities were associated with the spatial distribution of phthalates in sediments considering its relationship with population distribution characteristics of Beijing.

Vancomycin is mainly used as an antibacterial agent of last resort, but recently vancomycin-resistant bacterial strains have been emerging. Although new antimicrobials have been developed in order to overcome drug-resistant bacteria, many are structurally complex beta-lactams or quinolones. In this study, we aimed to create new anti-drug-resistance antibacterials which can be synthesized in a few steps from inexpensive starting materials. Since sulfa drugs function as p-aminobenzoic acid mimics and inhibit dihydropteroate synthase (DHPS) in the folate pathway, we hypothesized that sulfa derivatives would act as folate metabolite-mimics and inhibit bacterial folate metabolism. Screening of our sulfonanilide libraries, including benzenesulfonanilide-type cyclooxygenase-1-selective inhibitors, led us to discover benzenesulfonanilides with potent anti-methicillin-resistant Staphylococcus aureus (MRSA)/vancomycin-resistant Enterococcus (VRE) activity, that is, N-3,5-bis(trifluoromethyl)phenyl-3,5-dichlorobenzenesulfonanilide (16b) [MIC=0.5microg/mL (MRSA), 1.0microg/mL (VRE)], and 3,5-bis(trifluoromethyl)-N-(3,5-dichlorophenyl)benzenesulfonanilide (16c) [MIC=0.5microg/mL (MRSA), 1.0microg/mL (VRE)]. These compounds are more active than vancomycin [MIC=2.0microg/mL (MRSA), 125microg/mL (VRE)], but do not possess an amino group, which is essential for DHPS inhibition by sulfa drugs. These results suggested that the mechanism of antibacterial action of compounds 16b and 16c is different from that of sulfa drugs. We also confirmed the activity of these compounds against clinical isolates of Gram-positive bacteria.

The intensity distribution and the radiation force of the J 0 -correlated Schell-model (JSM) vortex beams focused by a lens are investigated. It is shown that the desired partially coherent vortex bottle beams in the focal region can be obtained by choosing appropriate values of the topological charge n and the correlation length σ . It is shown that such vortex bottle beam ( n ⩾ 1 ) has several advantages over the bottle beam (n = 0). In addition, the degree of coherence is also shown to possess phase singularities.

Nanocomposites of polystyrene, high impact polystyrene, acrylonitrile–butadiene–styrene terpolymer, polypropylene, and polyethylene were prepared using a methyl methacrylate oligomerically-modified clay by melt blending and the thermal stability and fire retardancy were studied. These nanocomposites were characterized by X-ray diffraction, transmission electron microscopy, thermogravimetric analysis and cone calorimetry. The results show a mixed morphology, depending on the polymer.

Polymeric nanocomposites (PNC) of polstyrene (PS) with organoclay were studied for their rheological and mechanical behavior. The organoclay (COPS) is a product of clay quaternization with a copolymer of styrene with vinyl benzyl tri-methyl ammonium chloride. PNC preparation and characterization was described in Part I of this paper. The clay platelets in COPS and its PNC's are well dispersed, i.e. with the interlayer spacings of d 001 =7–8 nm. By contrast, d 001 =3–4 nm for PNC with Cloisite ® 10A. However, the COPS in PS formed large, deformable domains. At concentration exceeding 5.8-wt% of COPS, the domains started to form a three-dimensional network with enhanced elasticity and progressive viscoelastic non-linearity. At temperatures of 160–180 °C the neat COPS did not flow; its behavior resembled that of a crosslinked elastomer. Application of the time–temperature superposition led to master curves of bending moduli vs. 19 decades of reduced frequency. The curves indicated a transition at ca. 180 °C, most likely associated with the disintegration of ammonium ion clusters. With the same amount of clay the mechanical properties of PNC with COPS were slightly worse than those with Cloisite ® 10A—the immiscibility of COPS, and the presence of extractable (by the matrix) low molecular weight compounds explain the behavior.

Nanocomposites of polystyrene (PS) were prepared using a melt compounding or co-solvent method. Two commercial PS were used, and two organoclays—one prepared in this laboratory (COPS), and the other commercial Cloisite® 10A (C10A). The COPS is a product of clay intercalation with a copolymer of styrene and vinyl benzyl tri-methyl ammonium chloride. According to the XRD diffraction data, the clay platelets in COPS and its PNC with PS were relatively well dispersed, i.e. with the interlayer spacings of d001=7–8 nm. By contrast, d001 in PNC prepared with C10A was only 4 nm. However, the number of clay platelets per stack in PS/COPS was found to be significantly larger than that in PS/C10A, viz. m=3–12, compared to m=2–6. The scanning and transmission electron microscopy indicated that in the PS matrix COPS existed in form of large, immiscible domains.

A methyl methacrylate oligomerically-modified clay was used to prepare poly(methyl methacrylate) clay nanocomposites by melt blending and the effect of the clay loading level on the modified clay and corresponding nanocomposite was studied. These nanocomposites were characterized by X-ray diffraction, transmission electron microscopy, thermogravimetric analysis and cone calorimetry. The results show a mixed intercalated/delaminated morphology with good nanodispersion. The compatibility between the methylacrylate-subsituted clay and poly(methyl methacrylate) (PMMA) are greatly improved compared to other oligomerically-modified clays.

Novel modified clays, which may enable the formation of flame retarded polystyrene nanocomposites by melt or solution blending, have been prepared using an ammonium salt which contains an oligomeric material consisting of vinylbenzyl chloride, styrene and vinyl phosphate reacting with dimethylhexadecylamine. These nanocomposites have been characterized by X-ray diffraction, transmission electron microscopy, thermogravimetric analysis, cone calorimetry and the evaluation of mechanical properties. Melt blending is an effective, economical way to produce intercalated nanocomposites with greatly reduced peak heat release rate and a decreased total heat release; the polymer does not all undergo thermal degradation.

Nanocomposites of polystyrene, high impact polystyrene, acrylonitrile–butadiene–styrene terploymer, polypropylene and polyethylene have been prepared using an organically-modified clay that contains polycaprolactone—PCL-modified clay. Depending upon the mode of preparation of the PCL-modified clay, all three types of nanocomposites, immiscible, intercalated and exfoliated, may be produced. The materials have been characterized by X-ray diffraction, transmission electron microscopy, cone calorimetry, thermogravimetric analysis, and the evaluation of mechanical properties.

Corrigendum Corrigendum to ‘‘Analgesic agents without gastric damage: Design and synthesis of structurally simple benzenesulfonanilide-type cyclooxygenase-1-selective inhibitors’’ [Bioorg. Med. Chem. 15 (2007) 1014–1021] Xiaoxia Zheng, Hiroyuki Oda, Kayo Takamatsu, Yukio Sugimoto, Akihiro Tai, Eiichi Akaho, Hamed Ismail Ali, Toshiyuki Oshiki, Hiroki Kakuta* and Kenji Sasaki Division of Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 1-1-1, Tsushima-Naka, Okayama 700-8530, Japan Division of Chemistry and Biochemistry, Okayama University Graduate School of Natural Science and Technology, 3-1-1, Tsushima-Naka, Okayama 700-8530, Japan Faculty of Pharmaceutical Sciences, High Technology Research Center (Life Science Center), Kobe Gakuin University, 518 Arise, Ikawadani-cho, Nishi-ku, Kobe 651-2180, Japan