Anti-inflammatory effects of farrerol on IL-1ß-stimulated human osteoarthritis chondrocytes.

The present study aimed to investigate the anti-inflammatory effects and the underlying molecular mechanism of farrerol on IL-1ß-stimulated human osteoarthritis chondrocytes. Chondrocytes were pretreated with farrerol 1h before IL-1ß stimulation. The effects of farrerol on NO and PGE2 production were tested by Griess reagent and ELISA. The effects of farrerol on COX-2, iNOS, Akt, phosphorylated Akt, and NF-κB activation were measured by western blot analysis. The results showed that farrerol remarkably inhibited IL-1ß-induced NO and PGE2 production, as well as COX-2 and iNOS expression. Farrerol also inhibited IL-1ß-induced NF-κB activation. Furthermore, farrerol significantly inhibited IL-1ß-induced phosphorylation of PI3K and Akt. In conclusion, these results indicated that farrerol inhibited IL-1ß-induced inflammatory responses in osteoarthritis chondrocytes by blocking PI3K/Akt/NF-κB signaling pathway.

A facile method for synthesis of N-doped ZnO mesoporous nanospheres and enhanced photocatalytic activity.

A facile synthesis route is reported for preparation of N-doped mesoporous ZnO nanospheres by a solvothermal treatment of Zn(NO3)2·6H2O which provides a source of both zinc and nitrogen. A variety of different spectroscopic and analytical techniques, such as powder X-ray diffraction (XRD), transmission electron microscopy (TEM), UV-vis and X-ray photoelectron (XPS) spectroscopies were used to characterize the physicochemical properties of catalysts. The photocatalytic activities of the composites were evaluated by the degree of degradation of rhodamine B in aqueous solutions at room temperature with near-UV light irradiation. These nanocomposites exhibit higher photocatalytic activity compared with pure ZnO nanoparticles. The enhancement of photocatalytic activity of N-doped ZnO nanoparticles is mainly attributed to their absorption of more photons and reduced electron-hole pair recombination. Our one-step, environmentally friendly synthetic method may provide a new means of designing and synthesizing series of N-doped metal oxide semiconductors for use in photo-assisted catalytic reactions.

A flexible nanobrush pad for the chemical mechanical planarization of Cu/ultra-low-к materials.

A new idea of polishing pad called flexible nanobrush pad (FNP) has been proposed for the low down pressure chemical mechanical planarization (CMP) process of Cu/ultra-low-к materials. The FNP was designed with a surface layer of flexible brush-like nanofibers which can 'actively' carry nanoscale abrasives in slurry independent of the down pressure. Better planarization performances including high material removal rate, good planarization, good polishing uniformity, and low defectivity are expected in the CMP process under the low down pressure with such kind of pad. The FNP can be made by template-assisted replication or template-based synthesis methods, which will be driven by the development of the preparation technologies for ordered nanostructure arrays. The present work would potentially provide a new solution for the Cu/ultra-low-к CMP process.

Preparation, characterization and formation mechanism of thermoplastic polyurethane nanostructures using solution wetting template.

Template wetting with polymer solutions has not been well understood up to now, and the formation mechanism of polymer nanostructures with this method is still to be revealed. In the present work, thermoplastic polyurethane (TPU) nanostructures were prepared by wetting cylindrical nanopores in an anodic aluminum oxide (AAO) membrane with TPU solution in dimethylformamide (DMF) followed by solvent evaporation. Both tubular structures and solid structures were simultaneously observed at four different concentrations of TPU solutions (i.e., 5, 7, 10, and 15 wt%) by a scanning electron microscope (SEM) and a transmission electron microscope (TEM). Furthermore, a transition from a tubular structure to a solid structure was also found at a higher concentration of TPU solution (15 wt%). It is speculated that the top part of the single nanostructure is tubular, and the lower part is solid. A "capillary wetting-evaporation-deposition" mechanism is given to explain such a phenomenon. According to this mechanism, the higher polymer concentration, the larger amount of solution, and the smaller pore size are believed to be beneficial for the formation of solid structures.

[Latest changes of joint proprioceptive function after posterior cruciate ligament reconstruction using double-bundle semitendinosus and gracilis under arthroscopy].

OBJECTIVE: To explore latest changes of joint proprioceptive function after posterior cruciate ligament (PCL) reconstruction using double-bundle semitendinosus and gracilis under arthroscope. METHODS: From June 2001 to November 2002, 25 patients with PCL ruptures were treated by arthroscope PCL reconstruction using double-bundle semitendinosus and gracilis, among whom 19 were males and 6 were females, aged 16-58 years old (36 on average). There were 6 cases of exercise injury, 15 of vehicle accident and 4 of falling injury. The duration before the operation was 1 week to 4 months (2.5 months on average). The posterior drawer test showed 23 patients were positive and 2 patients in the acute stage were not cooperative. MRI indicated that all the patients had PCL injuries. The proprioceptive function of the knee joints was (4.73 +/- 0.12) degrees before operation. RESULTS: All patients' incisions obtained healing by first intention after the operation. The posterior drawer test showed that all the patients were negative. All 25 patients were followed up for 20-41 months (30.1 months on average). Eighteen months after operation, MRI indicated that bone marrow canal healed and internal fixation was stable. At the time of the last follow-up, the Lysholm score increased from (58.6 +/- 15.2) before operation to (93.2 +/- 7.4), and there was statistical difference (P < 0.05). The proprioceptive function of the knee joints was (5.67 +/- 0.32) degrees, (5.45 +/- 0.16) degrees, (3.80 +/- 0.01) degrees and (3.67 +/- 0.25) degrees at 5, 10, 15 and 20 months after operation, respectively. Statistical differences were observed between groups at 5, 10, 15, 20 months and the group before operation (P < 0.05). The proprioceptive function of the knee joints was (4.56 +/- 0.11) degrees at the final follow-up, and was significantly different from that of the normal knee joints was (2.13 +/- 0.41) degrees, (P < 0.05). CONCLUSION: Joint proprioceptive function decreases temporally after the arthroscopy PCL reconstruction and begins to restore 15 months after operation, and improves sharply 20 months after operation. All patients' Lysholm scores and symptoms improve after operation. Therefore, the operation is effective.