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New tetradentate Schiff base chloro complexes of U(iv) and Th(iv) are prepared by salt metathesis approaches. These compounds undergo clean salt metathesis with NaN 3 to generate stable pseudo-trans azide compounds. The uranium dichloro complex also undergoes 2 e - oxidation with excess NaNO 2 to generate the uranyl derivative. All classes of complexes are characterized by single crystal X-ray diffraction and NMR spectroscopy.

Background and Objectives: The Tick programme of the National Heart Foundation (NHF) is the longest standing voluntary front of pack signpost nutrition logo in New Zealand. It provides a platform for collaboration with the food industry to encourage development of healthier products. This study evaluated the impact of the Tick programme on sodium in processed food., Methods and Study Design: Fifty-two Tick programme products from food categories known to contribute substantially to sodium intake were identified. Sales volumes (kg) from January 2011 to December 2013 were multiplied by changes in sodium content over that time, producing an estimate of programme impact. Five semi-structured interviews with industry representatives were conducted, to look at other influences for sodium reduction, and themes identified through methods of thematic analysis., Results: Over the period, the Tick programme influenced food companies to remove approximately 16 tonnes of salt through the reformulation and formulation of 52 Tick-approved breakfast cereals, edible oil spreads, cooking sauces and processed poultry products. Other factors influencing sodium reduction reported by company representatives included increased consumer and industry interest in healthier product nutrition profiles and other sodium reduction programmes targeting reformulation/formulation., Conclusions: The Tick remains a credible and well-recognized brand and may provide a competitive edge for participating food manufacturers in the current market. The Tick programme is effective in influencing industry to reduce sodium in processed foods in New Zealand. The combined impact of the Tick and other NHF programmes has the potential to reduce population sodium intake and improve health outcomes.

Objective: Nutritional impact of the Tick front-of-pack labelling programme was evaluated by investigating nutrient changes to the purchased food supply and the nutritional quality of Tick v. non-Tick products. Factors influencing manufacturers' decisions to develop and license Tick products were also explored., Design: Observational, cross-sectional and change over time data., Setting: New Zealand food supply, 2011-2013., Subjects: Forty-five newly licensed Tick products from five food categories were analysed: Edible Oil Spreads, Yoghurt & Dairy Desserts, Frozen Desserts, Ready Meals and Processed Poultry. Four manufacturers of these products were interviewed., Results: Eligible products (31 % of all Tick products in these categories) removed 4·1 million megajoules of energy, 156·0 tonnes of saturated fat, 15·4 tonnes of trans-fat and 4·0 tonnes of sodium from food products sold in New Zealand over three years. In each food category, these Tick products were, on average, 14-76 % lower in energy, saturated fat, trans-fat and sodium than non-Tick products, indicating healthier options. Participating manufacturers reported that international market trends and consumer demand for tasty, healthy foods primarily influenced Tick product development and sales. Tick was used as part of their marketing strategy as it was perceived as a credible, well-recognised logo for New Zealand consumers. Tick was cited as the primary initiative encouraging saturated fat reduction., Conclusions: The Tick Programme is continuing to encourage manufacturers to make meaningful improvements to the nutritional quality of the New Zealand food supply. Over time, these changes are likely to influence population nutrient intakes and reduce CVD risk factors.

The syntheses of a series of tris(amidate) mono(amido) titanium and zirconium complexes are reported. The binding motif of the amidate ligand has been determined to depend on the size of the metal centre for these sterically demanding N,O-chelating ligands; the larger zirconium metal centre supports three κ(2)-(N,O) bound amidate ligands while the titanium analogue has one ligand bound in a κ(1)-(O) fashion to alleviate steric strain. Reactivity studies indicate that, despite high steric crowding about the tris(amidate) mono(amido) zirconium metal centre, transamination of the reactive dimethylamido ligand can be achieved using aniline. This complex is also an active precatalyst for intramolecular alkene hydroamination, in which protonolysis of one amidate ligand in the presence of excess amine is observed as an initiation step prior to catalytic turnover. Eight-coordinate homoleptic κ(2)-amidate complexes of zirconium and hafnium have also been prepared.

Uranium nitride [U[triple bond]N](x) is an alternative nuclear fuel that has great potential in the expanding future of nuclear power; however, very little is known about the U[triple bond]N functionality. We show, for the first time, that a terminal uranium nitride complex can be generated by photolysis of an azide (U-N=N=N) precursor. The transient U[triple bond]N fragment is reactive and undergoes insertion into a ligand C-H bond to generate new N-H and N-C bonds. The mechanism of this unprecedented reaction has been evaluated through computational and spectroscopic studies, which reveal that the photochemical azide activation pathway can be shut down through coordination of the terminal azide ligand to the Lewis acid B(C(6)F(5))(3). These studies demonstrate that photochemistry can be a powerful tool for inducing redox transformations for organometallic actinide complexes, and that the terminal uranium nitride fragment is reactive, cleaving strong C-H bonds.

Reaction of the uranium alkyl complex (C(5)Me(5))(2)UMe(2) (1) with Et(3)N.3HF in toluene in the presence of a donor ligand (pyridine or trimethylphosphine oxide) results in gas evolution and the formation of the uranium(IV) difluoride complexes (C(5)Me(5))(2)UF(2)(L) (L = NC(5)H(5) (2), Me(3)P=O (3)). Similarly, reaction of (C(5)Me(5))(2)U[kappa(2)-(C,N)-CH(2)Si(CH(3))(2)N(SiMe(3))] (5) with Et(3)N.3HF in toluene gives the uranium(IV) amide-fluoride complex (C(5)Me(5))(2)U[N(SiMe(3))(2)](F) (6). The fluoride complex (C(5)Me(5))(2)UF(2)(NC(5)H(5)) (2) shows versatile reaction chemistry with a variety of trimethylsilyl reagents and demonstrates that the U-F bond provides an attractive synthetic strategy for accessing new functional groups that are not available from alkoxide or chloride complexes.

A comparative examination of the electronic interactions across a series of trimetallic actinide and mixed lanthanide-actinide and lanthanum-actinide complexes is presented. Using reduced, radical terpyridyl ligands as conduits in a bridging framework to promote intramolecular metal-metal communication, studies containing structural, electrochemical, and X-ray absorption spectroscopy are reported for (C(5)Me(5))(2)An[-N horizontal lineC(Bn)(tpy-M{C(5)Me(4)R}(2))](2) (where An = Th(IV), U(IV); Bn = CH(2)C(6)H(5); M = La(III), Sm(III), Yb(III), U(III); R = H, Me, Et) to reveal effects dependent on the identities of the metal ions and R-groups. The electrochemical results show differences in redox energetics at the peripheral "M" site between complexes and significant wave splitting of the metal- and ligand-based processes indicating substantial electronic interactions between multiple redox sites across the actinide-containing bridge. Most striking is the appearance of strong electronic coupling for the trimetallic Yb(III)-U(IV)-Yb(III), Sm(III)-U(IV)-Sm(III), and La(III)-U(IV)-La(III) complexes, [8](-), [9b](-), and [10b](-), respectively, whose calculated comproportionation constant K(c) is slightly larger than that reported for the benchmark Creutz-Taube ion. X-ray absorption studies for monometallic metallocene complexes of U(III), U(IV), and U(V) reveal small but detectable energy differences in the "white-line" feature of the uranium L(III)-edges consistent with these variations in nominal oxidation state. The sum of these data provides evidence of 5f/6d-orbital participation in bonding and electronic delocalization in these multimetallic f-element complexes. An improved, high-yielding synthesis of 4'-cyano-2,2':6',2''-terpyridine is also reported.

Easily prepared and highly modular organic amide proligands have been used to synthesize a series of new bis(amidate)-bis(amido) Ti and Zr complexes via protonolysis. These complexes have been structurally characterized by NMR spectroscopy and X-ray crystallography. The solid-state molecular structures of these complexes indicate that the amidate ligands bind to the metal centers in an exclusively bidentate fashion, resulting in discrete monomeric species. Geometric isomerism in these species is highly dependent upon the steric characteristics of the proligands utilized in the synthesis. In solution, these complexes are observed to isomerize on the NMR time scale, with one isomer being predominant. Bonding in the bis(amidate)-bis(amido) complexes was investigated by DFT calculations. The geometric isomers predicted by theory matched the experimentally observed results, within experimental error. The orbitals associated with amidate-metal bonding are energetically well below the frontier orbitals. The HOMO in these complexes is a pi orbital associated with amido ligand-to-metal bonding character, while the LUMO in all cases is a vacant d orbital on the metal center.

A series of bis(amidate)group 4-bis(amido) complexes have been prepared, characterized and have been shown to be highly tunable precatalysts for both the intra- and intermolecular hydroamination of alkynes.

Primary biliary cirrhosis (PBC) is a liver disease characterized by serum autoantibodies against the pyruvate dehydrogenase complex (PDC) located in the inner mitochondrial membrane. The predominant target in PDC has previously been localized to the inner lipoyl domain (ILD) of the E2 subunit. The etiology of PBC is unknown, although molecular mimicry with bacterial PDC has been proposed. Here, we have investigated the etiology of PBC and nature of the autoimmune response by analyzing the structure of a human monoclonal antibody with ILD specificity. Mutants of the monoclonal antibody, which was originally isolated from a patient with PBC, were expressed as Fab by phage display, and tested for reactivity against recombinant domains of the E2 subunit. Fab in which the V(H)-encoded portions were reverted to germline lost reactivity against the ILD alone, but recognized a different epitope in a didomain construct encompassing the ILD, hinge region and E1/E3 binding domain. The complete V(H) and V(L )germline revertant was unreactive with the human ILD and didomain, the Escherichia coli didomain, and whole PDC. We hypothesize that the IgM on the surface of the naïve B-cell first recognizes an as yet unidentified antigen, and that accumulation of somatic mutations results in an intermolecular epitope shift directed towards an epitope involving the E1/E3 binding domain. Further mutations result in the specificity being redirected to the ILD. These findings also suggest that bacterial molecular mimicry is not involved in initiating disease., (Copyright 2001 Academic Press.)

Acute liver failure arises from an imbalance between liver cell death and regeneration. The severity of the insult determines whether liver cells die by apoptosis or necrosis, and this in turn affects the magnitude of the inflammatory reaction. Liver cell death occurs through complex cellular interactions and is mediated by immunological, inflammatory and chemical components. Regeneration of the liver cell mass also depends on cellular interactions, often involving those same mediators implicated in the injury itself. A greater understanding of these processes will lead ultimately to targeted rational therapy in acute liver failure.

Background/aims: Autoantibodies with specificity for the E2 component of the pyruvate dehydrogenase complex (PDC-E2) are commonly present in primary biliary cirrhosis. The aim of this study was to generate and characterise human anti-PDC-E2 monoclonal antibodies and analyse immunoglobulin gene usage and mutation for clues to pathogenesis., Methods: Peripheral B-lymphocytes from two patients with primary biliary cirrhosis were used to generate heterohybridomas secreting PDC-E2 specific monoclonal antibodies. The antibodies were characterised by ELISA, immunoblotting, indirect immunofluorescence and enzyme inhibition techniques, and their encoding immunoglobulin genes were amplified, cloned and sequenced., Results: Four IgGlambda and one IgMlambda monoclonal antibodies specific for PDC-E2 were generated: all gave bands at 74 kD and 52 kD on PDC immunoblots, two clones were specific for the lipoylated inner lipoyl domain, and all inhibited target enzyme function. Sequence analysis suggested unrestricted VH gene usage, but a strong preference for lambda light chains. The extent of somatic mutation was high (3-20%), with evidence for antigen selection in 3/5 VH sequences., Conclusions: These monoclonal antibodies closely resemble the hallmark autoantibodies of primary biliary cirrhosis. Their specificities demonstrate true cross reactivity between an epitope on PDC-E2 and Protein X, and the existence of a subset of B cells that recognise only the lipoylated form of the antigen. The pattern of immunoglobulin gene mutations suggests an antigen-driven selection of high affinity IgG autoantibodies, supporting a possible role for exogenous antigen in the pathogenesis of primary biliary cirrhosis.