Bromate removal from drinking water by semiconductor photocatalysis

The semiconductor photocatalyst, platinised titanium dioxide, Pt/TiO2, is used to promote the destruction of bromate ions to bromide and oxygen by 254 nm ultraviolet light. The kinetics of bromate removal are first order with respect to [BrO3-] and are inhibited, although not completely, by competitive adsorption by other anions, including bromide and sulfate ions. The Pt/TiO2 can be used not only as a powder dispersion, but also as a thin film in a flow reactor for the destruction of bromate ions. Copyright (C) 1996 Elsevier Science Ltd

SULFADIMIDINE IN DRINKING TROUGHS AT BACON FACTORIES

Water troughs in the lairages of three bacon factories were examined. Pigs were observed drinking from the troughs, some of which were contaminated with faeces. Some of the troughs contained detectable concentrations of sulphadimidine, and the highest concentration recorded was 17 mu-g/ml. Pigs which drank this contaminated water before slaughter could contain tissue residues of sulphadimidine above the permitted concentration.

Context-Dependent Pharmacology Exhibited by Negative Allosteric Modulators of Metabotropic Glutamate Receptor 7

Phenotypic studies of mice lacking metabotropic glutamate receptor subtype 7 (mGluR7) suggest that antagonists of this receptor may be promising for the treatment of central nervous system disorders such as anxiety and depression. Suzuki et al. (J Pharmacol Exp Ther 323: 147-156, 2007) recently reported the in vitro characterization of a novel mGluR7 antagonist called 6-(4-methoxyphenyl)-5-methyl-3-(4-pyridinyl)-isoxazolo[4,5-c]pyridin-4(5H)-one (MMPIP), which noncompetitively inhibited the activity of orthosteric and allosteric agonists at mGluR7. We describe that MMPIP acts as a noncompetitive antagonist in calcium mobilization assays in cells coexpressing mGluR7 and the promiscuous G protein G alpha(15). Assessment of the activity of a small library of MMPIP-derived compounds using this assay reveals that, despite similar potencies, compounds exhibit differences in negative co-operativity for agonist-mediated calcium mobilization. Examination of the inhibitory activity of MMPIP and analogs using endogenous G(i/o)-coupled assay readouts indicates that the pharmacology of these ligands seems to be context-dependent, and MMPIP exhibits differences in negative cooperativity in certain cellular backgrounds. Electrophysiological studies reveal that, in contrast to the orthosteric antagonist (2S)-2-amino-2-[(1S,2S)-2-carboxyclycloprop-1-yl]-3-(xanth-9-yl) propanoic acid (LY341495), MMPIP is unable to block agonist-mediated responses at the Schaffer collateral-CA1 synapse, a location at which neurotransmission has been shown to be modulated by mGluR7 activity. Thus, MMPIP and related compounds differentially inhibit coupling of mGluR7 in different cellular backgrounds and may not antagonize the coupling of this receptor to native G(i/o) signaling pathways in all cellular contexts. The pharmacology of this compound represents a striking example of the potential for context-dependent blockade of receptor responses by negative allosteric modulators.