Microglia-mediated inflammation is implicated in pathogenesis of neurodegenerative diseases. Oroxylin A, a flavonoid isolated from Scutellariae baicalensis, has been shown to ameliorate microglia activation-mediated neurodegeneration in vivo. The molecular mechanism underlying the inhibitory effects of oroxylin A on microglia activation, however, remains unknown. In the present study, effects of oroxylin A co-treated with lipopolysaccharide (LPS, 100 ng/ml) on LPS-induced activation of cultured microglial BV-2 cells were examined. Nitric oxide (NO) production was determined by Greiss method. Expression of inducible nitric oxide synthase (iNOS), interleukin (IL)-1β and IL-6 was assessed using real-time RT-PCR or Western blot analysis. Furthermore, activation of the nuclear factor κB (NFκB) and the signal transducer and activator of transcription 1 (STAT1) was examined by Western blot analysis and transcription factor DNA-binding activity assay. Our results indicated that oroxylin A (10–100 µM) in a concentration-dependent manner inhibited LPS-induced NO production via blocking iNOS expression at both mRNA and protein levels without affecting the degradation rate of iNOS mRNA. Moreover, oroxylin A significantly attenuated LPS-induced late expression (20 hours after LPS challenge) of IL-1β and IL-6. Furthermore, oroxylin A significantly suppressed LPS-induced JAK2-mediated STAT1 phosphorylation without affecting LPS-induced NFκB-p65 nuclear translocation or NFκB-p65 DNA-binding activity. This is consistent with the finding that AG490, a specific JAK2 inhibitor, significantly inhibited LPS-induced STAT1 phosphorylation with almost completely diminished iNOS expression. These results suggest that oroxylin A, via suppressing STAT1 phosphorylation, inhibits LPS-induced expression of pro-inflammatory genes in BV-2 microglial cells.

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In this paper, both the modal testing method and amplitude-fluctuation (AF) electronic speckle pattern interferometry (ESPI) were used to measure the resonant frequencies, mode shapes, phase distribution and whole-field displacements of composite plates with and without defects. Square-and circular-shape defects of two different sizes were used in the composite plates. Two different stacking sequences of the composite plates were adopted, i.e. [0/90] 3S and [±45] 3S . Composite plates containing simulated defects located from the 3 rd to 6 th layer numbering from the top of the plates were fabricated, respectively. It was found that both the anomaly of the AF-ESPI fringe pattern around the defect and the decrease of resonant frequencies due to the defect are feasible ways to detect the existence of the defect. To explain the local effect of the defect at higher frequencies, vibration theory of thin plate with fixed ends for the square shape defect was employed.

The small-sized herringbone groove journal bearing ͑HGJB͒, i.e., so-called "magnetic bearing," filled with Newtonian ferrofluid lubrication is investigated via finite difference analysis ͑FDA͒, with consideration of cavitation zones in HGJB. The FDA starts with constructing the mass flux equations of the HGJB filled with ferrofluid. Discretization for FDA is next performed over the bearing clearance domain, from which algebraic finite difference equations based on the mass flow balance over the clearance domain are derived. Solving the equations, rotordynamic coefficients, cavitation zones, and side leakage rate are successfully predicted to show effectiveness in enhancing bearing performance by ferrofluid.