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    Application of broadband acoustic resonance dissolution spectroscopy (BARDS) to the gas release behaviour during rehydration of milk protein isolate agglomerates
    (Elsevier Ltd, 2019) Wu, Shaozong; Fitzpatrick, John; Cronin, Kevin; Ahmed, M. Rizwan; Fitzpatrick, Dara; Miao, Song; China Scholarship Council; Teagasc
    The BARDS technique was applied in this study to acoustically assess the rehydration behaviour of milk protein isolate (MPI) agglomerates and to compare with regular MPI powder. The results showed that BARDS has potential to monitor the rehydration behaviour of agglomerates. The greater porosity (>70%) of agglomerated powders introduced more compressible gas into the water. The BARDS profile showed that there was faster initial gas release from the agglomerates, indicating better wetting and dispersion ability of the agglomerates with shorter t M (time of maximum gas volume in solution). At 0.10% powder addition, agglomerated MPI reached t M within 109 s, which was significantly less than the control MPI at 140 s. MPI with lactose binder (MPI-L) had a t M of 80 s at 0.10% powder addition and, larger size MPI-L had a t M of 60 s. At 0.20% and 0.30% powder addition, more time was required to wet and disperse the powders. © 2019 Elsevier Ltd
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    Synthesis and biological evaluation of novel isoellipticine derivatives and salts
    (Royal Society of Chemistry, 2012-08-24) Miller, Charlotte M.; O’Sullivan, Elaine C.; Devine, Ken J.; McCarthy, Florence O.; Higher Education Authority
    Synthesis of novel 7-substituted isoellipticines and isoellipticinium salts is described, with optimisation of routes, representing a new class of anti-cancer agent. Initial assessment of biological activity using a topoisomerase II decatenation assay and NCI screening highlighted strong anti-cancer activity, further developed in a panel of isoellipticinium salts. Interestingly, low correlation between results of the topoisomerase II decatenation assay and NCI screen throughout the panel suggest that topo II is not the most important biological target with respect to anti-cancer activity in this new class of compounds. Results also suggest that solubility is not the limiting factor in activity of the isoellipticinium salts. Overall, 20 novel ellipticine analogues were prepared and full anti-cancer profiling was completed for 13 isoellipticine derivatives and salts. Two compounds display significant specificity towards CNS cancer cell lines and are lead compounds for future development.
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    Isolation, biological activity and synthesis of the natural product ellipticine and related pyridocarbazoles
    (Royal Society of Chemistry, 2012-05) Miller , Charlotte M.; McCarthy, Florence O.; Higher Education Authority
    The tetracyclic natural product ellipticine (5,11-dimethyl-6H-pyrido[4,3-b]carbazole) was first isolated from the plant material of Ochrosia elliptica Labill in 1959. Woodward et al. reported the first synthesis of ellipticine later the same year, and this was followed by many different synthetic strategies in subsequent decades. Investigation of the biological activity of ellipticines uncovered potent anti-cancer properties and several ellipticine derivatives have been the subject of clinical trials. The ellipticine family of compounds exert their biological activity via several modes of action, the most well established of which are intercalation with DNA and topoisomerase II inhibition. In recent times other modes of action have been revealed, including kinase inhibition, interaction with p53 transcription factor, bio-oxidation and adduct formation. The scope of this review covers key features of the biological activity of ellipticine, with emphasis on new modes of action, followed by synthetic routes to ellipticine, including key early syntheses of pyrido[4,3-b]carbazoles and comprehensive coverage of the literature since the late 1980s, along with more recent syntheses of ellipticine analogues and substituted ellipticines.
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    Application of mean-field theory to the spin casting of polystyrene and poly(methyl methacrylate) blend films from toluene
    (Elsevier Ltd, 2019) Mouhamad, Youmna; Mokarian-Tabari, Parvaneh; Jones, Richard A.L.; Geoghegan, Mark; Engineering and Physical Sciences Research Council
    The Flory-Huggins free energy of mixing is shown to be appropriate for the analysis of the temporal evolution of a ternary blend of polystyrene and poly (methyl methacrylate) during spin-coating from toluene using an in-situ light scattering technique. For the range of concentrations studied, both the onset of film instability and the observation of a scattering ring occur at the same toluene volume fraction. The success of Flory-Huggins theory indicates that polymer chains retain random walk characteristics during spin-coating. It is also concluded that the thermodynamics of phase separation during film formation is independent of the initial solvent concentration. © 2019 Elsevier Ltd
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    Regioselective partial hydrogenation and deuteration of tetracyclic (Hetero)aromatic systems using a simple heterogeneous catalyst
    (Wiley, 2024-11-12) Kehoe, Roberta A.; Lowry, Amy; Light, Mark E.; Jones, David J.; Byrne, Peter; McGlacken, Gerard P.; Science Foundation Ireland
    The introduction of added ‘3-dimensionality’ through late-stage functionalization of extended (hetero)aromatic systems is a powerful synthetic approach. The abundance of starting materials and cross-coupling methodologies to access the precursors allows for highly diverse products. Subsequent selective partial reduction can alter the core structure in a manner of interest to medicinal chemists. Herein, we describe the precise, partial reduction of multicyclic heteroaromatic systems using a simple heterogeneous catalyst. The approach can be extended to introduce deuterium (again at late-stage). Excellent yields can be obtained using simple reaction conditions.