Hydrogen peroxide (H2O2) in dilute aqueous solution can be efficiently captured by co-crystallisation with enantiomeric and racemic amino acids as evidenced by colourimetric titration and the single crystal X-ray structural...

A thin film of δ‐type MnO2 grown cathodically has been investigated with respect to the ability toward anodic decomposition of H2O2 and durability. With polarization at less positive potentials than +0.4 V vs. Ag/AgCl, the film was dissolved exclusively as a result of reduction of Mn4+ sites in the oxide by H2O2 to soluble Mn2+. At +0.9 V, MnO2 remained unchanged and decomposed H2O2 in solution. At +0.8 V, the film was once dissolved in the initial stage; however, it was self‐healed via reoxidation of the liberated Mn2+ ions. Amperometric flow‐injection analysis of H2O2 was carried out with the δ‐MnO2 film.

No abstract

Pretreatment with synthetic C-reactive protein (CRP), a functional CRP peptide, has the potential to augment macrophage phagocytosis by bacterial challenge. However, the posttreatment is clinically ideal. We investigated the efficacy of posttreatment with synthetic CRP on murine cecal ligation and puncture (CLP), focusing on liver macrophages. Mice received CLP, and 1 h later, synthetic CRP or saline was intraperitoneally administered. Posttreatment with synthetic CRP increased the murine survival after CLP. It reduced viable bacterial counts in the liver 24 h after CLP with an increase in the number of Kupffer cells but not monocyte-derived liver macrophages. Posttreatment with synthetic CRP increased the phagolytic activity of Kupffer cells against <i>Escherichia coli</i> (<i>E. coli</i>) as well as capsulated <i>Klebsiella pneumoniae</i> at 3 h after CLP. Synthetic CRP therapy augmented TNF production by <i>E. coli</i>-phagocytosing Kupffer cells, resulting in an increase in tissue TNF levels in the liver at 24 h. Kupffer cells substantially expressed FcγRI, which is a ligand of CRP, and their FcγRI expression was further increased after CLP. In contrast, synthetic CRP therapy affected neither the phagocytic function of monocyte-derived liver macrophages (showing a weak FcγRI expression) nor their TNF production. Depletion of Kupffer cells in mice inhibited these beneficial effects of synthetic CRP in CLP mice. <b><i>Conclusion:</i></b> Posttreatment with synthetic CRP effectively improves murine bacterial peritonitis via the activation of phagocytosis of FcγRI-expressing Kupffer cells.

Multilayered manganese dioxide (MnO 2 ) film intercalated with tris(2,2-bypyridine)ruthenium(II) ([Ru(bpy) 3 ] 2+ ) was synthesized by a one-step electrochemical method. The obtained film was characterized by FTIR, XRD, SEM and TEM techniques. FTIR and XRD measurements revealed that [Ru(bpy) 3 ] ions are intercalated in the interlayer between MnO 2 layers and exist as a two-layer form. After immersion in water, the two-layer form was changed into the one-layer. Electrochemistry of the resulting films in Na 2 SO 4 solution indicated an electron transfer from/to the underlying Pt substrate to/from the incorporated complexes through the MnO 2 sheets. At this situation, [Ru(bpy) 3 ] ions were extracted to maintain the charge neutrality of the film.