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The total hydrogenation of furfural (FAL) in aqueous solution was investigated under mild conditions over a series of a physical mixture of Pd-and Ru-supported catalysts. Monometallic catalysts showed unfulfilled selectivity toward total hydrogenation: supported Pd catalysts tend to give a mixture of tetrahydrofufural (THFAL), furfuryl alcohol (FA), and tetrahydrofurfuryl alcohol (THFA) while supported Ru catalysts are apt to hydrogenate the CO bond. When supported Pd and Ru catalysts were mixed, the yield of THFA was significantly improved. A support-dependent promotion effect was noticed; in particular, Pd/Al 2 O 3 and Ru/ZrO 2 mixture gave 99% yield of THFA at 30 °C and 0.5 MPa H 2 . Detailed kinetics studies suggest that the reaction pathway with THFAL as the intermediate could be involved in this process. The apparent activation energy of furan hydrogenation over Pd/ Al 2 O 3 and the subsequent CO bond hydrogenation over Ru/ZrO 2 is about 21 and 30 kJ/mol, respectively. The low activation energies may well explain the observed activity of total hydrogenation of FAL over bimetallic mixtures. This two-step reaction process was also investigated in a fixed-bed reactor with a two-catalyst bed, which gave stable THFA yield and shows promising industrial application.

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The bispecific antibody is a novel antibody, which can target two different antigens and mediate specific killing effects by selectively redirecting effector cells to the target cells. Here, we designed and synthesized a bispecific antibody (BsAb) that can bind cellular-mesenchymal to epithelial transition factor (c-MET, overexpressed in several human solid tumor), and programmed death-1 (PD-1, involved in cancer cell immune evasion) with high affinity and specificity. We found that BsAb can induce the degradation of c-MET protein in cancer cells, including MKN45, a gastric cancer cell line, and A549, a lung cancer cell line. BsAb inhibited hepatocyte growth factor (HGF)-mediated proliferation, migration, and antiapoptosis, and downregulated HGF-stimulated phosphorylation of c-MET, protein kinase B (AKT), and extracellular signal-regulated kinase (ERK1/2). BsAb can also rescue T cell activation. Furthermore, xenograft analysis revealed that BsAb markedly inhibits the growth of subcutaneously implanted tumors and chronic inflammation. On the basis of these results, we have identified a potential bispecific drug, which can effectively target c-MET and PD-1 for the treatment of human solid cancers.

The influence of physical confinement on the crystallization of poly­(ethylene oxide) (PEO) has received much attention in past years. Here, rather than constraining the crystallization of the polymer by a physical or geometric boundaries, the influence of the constraints imposed by the chain architecture on the crystallization of the PEO was investigated, where the PEO chains were anchored to a poly­(norbornene) (PNB) backbone. In this brush or comb-type polymer, the crystallizable polymer PEO are side chains comprising the bristles of the brush while the PNB comprises the spine. The brush or comb-type polymers were synthesized by the ring-opening metathesis polymerization (ROMP) of a NB-modified macromonomer. Here, the crystallizable PEO is anchored to the PNB backbone, placing constraints on the PEO during crystallization and annealing. The crystalline morphologies, crystallization kinetics, melting behavior, and crystal structure of the resultant polymers were investigated by polarized optical microscopy (POM), different scanning calorimetry (DSC), and X-ray scattering. Constraining the PEO to the PNB backbone was found to significantly influence the mobility of PEO chains, the degree of crystallinity, the crystal thickness and the equilibrium melting point. Increasing the molecular weight of the PEO or annealing at higher temperature alleviates this constraint to some extent. In addition to crystallization, the influence of annealing on the morphology was also investigated.

We report a 'one step' method for preparing conductive thin films with cylindrical microdomains oriented normal to the surface over large areas using the supramolecular assembly of poly(styrene-block-4-vinylpyridine) (PS-b-P4VP) and 5,10,15,20-tetrakis(4-hydroxyphenyl)-21H,23H-porphine (HOTPP). The HOTPP interacts with the P4VP block by a hydrogen bonding between the hydroxyl group of HOTPP and pyridine ring of PS-b-P4VP, forming cylindrical P4VP(HOTPP) domains having an average diameter of 17 nm in a PS matrix. Dynamic light scattering, contact angle, and in situ grazing incidence small-angle X-ray scattering analyses show a morphological transition from spherical micelles in solution to cylindrical microdomains oriented normal to the substrate surface during the drying process. From the dependence of current on voltage, an average current of ~ 4.0 nA is found to pass through a single microdomain, pointing to a promising route for organic semiconductor device applications.

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