Gold nanoparticles on a number of supporting materials, including anatase TiO 2 (TiO 2 -A, in 40 nm and 45 μm), rutile TiO 2 (TiO 2 -R), ZrO 2 , Al 2 O 3 , SiO 2 , and activated carbon, were evaluated for hydrodeoxygenation of guaiacol in 6.5 MPa initial H 2 pressure at 300 °C. The presence of gold nanoparticles on the supports did not show distinguishable performance compared to that of the supports alone in the conversion level and in the product distribution, except for that on a TiO 2 -A-40 nm. The lack of marked catalytic activity on supports other than TiO 2 -A-40 nm suggests that Au nanoparticles are not catalytically active on these supports. Most strikingly, the gold nanoparticles on the least-active TiO 2 -A-40 nm support stood out as the best catalyst exhibiting high activity with excellent stability and remarkable selectivity to phenolics from guaiacol hydrodeoxygenation. The conversion of guaiacol (∼43.1%) over gold on the TiO 2 -A-40 nm was about 33 times that (1.3%) over the TiO 2 -A-40 nm alone. The selectivity of phenolics was 87.1%. The products are mainly phenolic compounds with no aromatics and saturated hydrocarbons such as cyclohexane. The gold particle size ranging from 2.7 to 41 nm and water content were found to significantly affect the Au/TiO 2 -A-40 nm catalyst activity but not the product selectivity. The reaction rates of 0.26 and 0.91 (min −1 g-cat −1 cm 3 ) were determined for guaiacol hydrogenation and catechol hydrogenation, respectively. Bimolecular methylation was established as the dominant mechanism for methyl group transfer among the phenolics. Two major pathways of guaiacol hydrogenation to phenolics over the 0.4Au-19 nm/TiO 2 -A-40 nm are proposed: (1) direct hydrogenation of guaiacol to form phenol and methanol, (2) hydrodehydroxylation of catechol intermediate from the transmethylation between guaiacol and phenol.

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The catalytic properties of physical mixtures of Ni particles (100−200 nm) with nanoparticles of anatase TiO 2 (TiO 2 -A), ZrO 2 , Al 2 O 3 , rutile TiO 2 (TiO 2 -R), and CeO 2 were investigated for the hydrodeoxygenation (HDO) of guaiacol. High selectivities to phenolics were obtained only for Ni mixed with anatase TiO 2 (Ni and TiO 2 -A), while saturated hydrocarbons were the main products for the mixtures with other supports. By thermal treatment in hydrogen gas only at 300 °C or higher and subsequently separating the large Ni particles from the TiO 2 -A particles with a magnet, it was further discovered that there was migration of TiO 2 from TiO 2 -A onto the large Ni particles, resulting in an amorphous TiO 2 overlayer on the Ni particles as evidenced by high-resolution TEM, and vice versa, migration of Ni onto TiO 2 -A. The TiO 2 overlayer rendered the Ni particles completely inactive as a hydrogenation/ hydrodeoxygenation catalyst. Conversely, the small amounts of Ni (<1.5 wt %) migrated onto TiO 2 -A formed highly dispersed Ni, undetectable by high-resolution TEM (<2 nm), that were remarkably highly active for HDO of guaiacol, producing selectively phenolics. Such highly selective HDO catalysts could also be formed by incipient wetness impregnation of Ni in loadings above 2 wt % onto the TiO 2 -A, but it was essential to pretreat the sample in H 2 at 300 °C or higher. Pretreatment in H 2 at 200 °C generated catalysts that produced saturated ring products. The activity of the impregnated catalysts, as measured by guaiacol conversion, increased linearly with Ni loading below 0.5 wt %. The activity continued to increase with Ni loading but more slowly up to 2 wt %, beyond which there was little further change. The results suggested that two types of Ni species existed on the TiO 2 -A surface. One type consisted of a cluster of Ni atoms that were dominant on larger Ni particles that were active in aromatic ring hydrogenation and hydrodeoxygenation. They were readily covered by reducible TiO 2 -A at 300 °C or higher due to the traditional strong metal support interaction (SMSI) effect and became inactive. Another type was clusters of a very small number of Ni atoms, perhaps one atom, that were present as highly dispersed Ni clusters interacting strongly with the defect sites of TiO 2 -A. The strong interaction of this type of Ni with the TiO 2 defect deterred TiO x migration allowing surface exposed Ni atoms to catalyze the HDO of guaiacol with very high selectivities that were not characteristic of typical Ni particles.

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Laparoscopic liver re-resection for patients with posthepatectomy HCC recurrence provided comparable perioperative and oncological outcomes as open liver re-resection and can be a safe alternative to open procedure.

Overexpression of the tumor necrosis factor receptor-associated factor 4 (TRAF4) has been detected in many cancer types and is considered to foster tumor progression. However, the role of TRAF4 in hepatocellular carcinoma (HCC) remains elusive. In this study, we found that TRAF4 was highly expressed in HCC cell lines and HCC tissues compared with normal liver cell lines and adjacent noncancerous tissues. TRAF4 overexpression in HCC tissues was correlated with tumor quantity and vascular invasion. In vitro studies showed that TRAF4 was associated with HCC cell migration and invasion. An in vivo study verified that TRAF4 overexpression facilitated metastasis in nude mice. In addition, overexpressed TRAF4 promoted the phosphorylation of Akt and induced Slug overexpression, leading to downregulated E-cadherin and upregulated vimentin, while silencing TRAF4 moderated the phosphorylation of Akt and repressed the expression of Slug, which resulted in upregulated E-cadherin and downregulated vimentin. These effects were inversed after pretreatment of the PI3K/Akt inhibitor LY294002 or overexpression of constitutively active Akt1. Our study demonstrated that TRAF4 was involved in promoting HCC cell migration and invasion. The process was induced by the EMT through activation of the PI3K/Akt signaling pathway.

We report the synthesis of bis(hydroxylmethylfurfuryl)amine (BHMFA) from 5-hydroxymethylfurfural (5-HMF) by reacting 5-HMF with primary amines in the presence of homogeneous Ru(II) catalysts having sterically strained ligands. BHMFA is a group of furan-based monomers that offer great potential to form functional biopolymers with tunable properties. A range of primary amines, such as aliphatic and benzyl amines, are readily converted with 5-HMF to form the corresponding BHMFA in good yields. The reaction proceeds through reductive amination of 5-HMF with primary amine to form secondary amine, followed by reductive amination of 5-HMF with in situ generated secondary amine to produce BHMFA.

Diketones are ubiquitous blocks for organic synthesis. This work shows a highly active catalyst for the production of diketone 1-hydroxyhexane-2,5-dione (HHD) by hydrogenation of 5-hydroxymethylfurfural (5-HMF), a biobased platform chemical. Half-sandwich Cp*Ir complexes with ortho-hydroxyl group functionalized bipyridine ligands were synthesized and found to exhibit remarkably high catalytic activity for this reaction in acidic water. The HHD formation rate was further increased when the bipyridine ligands of Cp*Ir complexes were modified by an electron-donating group. A bipyridine ligand with both dimethylamino and ortho-hydroxyl groups achieved a HHD formation turnover frequency (TOF) of 31 560 h–1 by H2 and a TOF of 6140 h–1 by formic acid, representing 180-fold and 3 000-fold over the activities of the best reported results, respectively.