SUMMARYToll-like receptors (TLR) are sentinel receptors capable of recognizing pathogen-associated molecule patterns (PAMP) such as lipopolysaccharide (LPS) and CpG-containing oligonucleotides (CpG ODN). TLR2 and TLR4 are major receptors for Gram-positive and Gram-negative bacterial cell wall components, respectively. TLR9 is necessary for CpG signalling. LPS or CpG ODN can activate immature dendritic cells (DC) and induce DC maturation characterized by production of cytokines, up-regulation of co-stimulatory molecules, and increased ability to activate T cells. However, little is known regarding the regulation of TLR gene expression in mouse DC. In this study, we investigated the regulation of TLR2, TLR4 and TLR9 gene expression by LPS in murine immature DC. TLR2, TLR4 and TLR9 mRNA were up-regulated following LPS stimulation. The up-regulation of TLR9 expression coincided with significantly increased production of tumour necrosis factor-a induced by LPS plus CpG ODN. While inhibition of extracellular signal-related kinase and NF-kB activation suppressed the up-regulation of the expression of TLR2, TLR4 and TLR9 mRNA, inhibition of p38 kinase prevented the up-regulation of TLR2 and TLR4 mRNA expression but enhanced the up-regulation of TLR9 expression. These results demonstrated that TLR2, TLR4 and TLR9 gene expression was differently regulated by LPS in mouse immature DC. Up-regulation of TLR2, TLR4 and TLR9 expression by LPS might promote the overall responses of DC to bacteria and help to explain the synergy between LPS and other bacterial products in the induction of cytokine production.

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Advanced research on structural steels has recently focused on the improvement of properties through the control of grain size. Grain refinement increases strength via the Hall-Petch relation, lowers the ductilebrittle transition by increasing resistance to transgranular cleavage, and reduces hydrogen embrittlement by minimizing interfacial fracture along grain or lath boundaries. However, given their different mechanisms, these properties require slightly different measures of the effective grain size. When the grains are smooth and random, all measures of the effective grain size are roughly equivalent. However, transformations in steel are often crystallographically coherent, producing a martensitic, bainitic or ferritic product that has either a Kurdumov-Sachs (KS) or a Nishiyama-Wasserman (NW) relation to the parent austenite. The 24 KS variants and 12 NW variants divide into three sets of eight, corresponding to the three Bain variants of the fcc→bcc transformation. Grain, packet or block boundaries that separate different Bain variants have significant misorientations of the {100} cleavage planes, but may have only slight misorientations of the {110} slip planes. It follows that grain refinement through coherent transformation is very effective in improving resistance to cleavage fracture and, if the boundary facets are small, to hydrogen embrittlement, but is often relatively ineffective in increasing strength. For this reason, grain refinement for increased strength is best done with incoherent transformations (such as the strain-induced ferrite transformation) while grain refinement for low-temperature toughness or hydrogen resistance is best done with coherent transformations that refine the effective grain size without overstrengthening to unacceptably low ductility.KEY WORDS: grain refinement; coherent transformations; strength; ductile-brittle transition; hydrogen embrittlement.and ductile-brittle transition temperature of structural steels obey relations of the Hall-Petch form. The yield strength is given by the classic Hall-Petch relation: (3) where K B is the appropriate Hall-Petch coefficient. While the same parameter, the grain size, d, appears in each of these equations, it is important to recognize that "grain size" has a different meaning for each of the properties of interest. The Effective Grain Size for StrengthAs we have discussed elsewhere, 5) several different theories have been advanced to explain the Hall-Petch relation for strength. Without taking a firm position with respect to these, they have the common feature that grain size limits the distance over which free slip can occur. In Fe, the primary slip planes are the {110} planes, so slip is limited by the dimension of the {110} planes within a grain. Hence the appropriate measure of grain size would appear to be the coherence length along {110}.The dependence of the Hall-Petch coefficient, K y , on the properties of the steel are also at least qualitatively common to the various theories. (4) where we have approximated the yie...

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The polyphenolic profiles of four berries (blueberry, bilberry, mulberry, and cranberry) in China were investigated using Fourier transform-ion cyclotron resonance mass spectrometry (FT-ICR MS). Thirty-nine polyphenols including 26 anthocyanins, 9 flavonoids, and 4 phenolic acids were identified accurately. Cyanidin aglycones are common in four berries, and malvidin aglycones are the main compounds found in bilberry and cranberry. The anthocyanin level in blueberry are the highest with 739.6 ± 17.14 mg/g DW and presented the strongest antioxidant capacity in DPPH, ABTS, FRAP, and ORAC assay. In α-glycosidase, the inhibition activity was in the following order: mulberry > bilberry > blueberry > cranberry. For the PTP1B inhibition assay, blueberry demonstrated the highest inhibitory effect with IC 3.06 ± 0.02 μg/mL, followed by bilberry, mulberry, and cranberry. Molecular docking results showed that cyanidin aglycones had the highest inhibition activity to PTP1B.

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