Abstract Cyclic ethers were efficiently converted to the corresponding hydroxyalkylphosphonium salts by the reaction with triphenylphosphine and trifluoromethanesulfonic or trifluoroacetic acid. The reaction of these salts with bases afforded the corresponding phosphonium inner salts which reacted with carbonyl compounds to give homoallylic alcohols.
Abstract The polysilsesquioxanes (PSQ) having alkoxyethylamide groups were prepared from the silane coupling reagents, prepared by addition reaction of alkoxyethylamines to (3-isocyanatopropyl)triethoxysilane, by condensation under acidic conditions. In the obtained PSQs, those having bis(methoxyethyl)amide or bis(ethoxyethyl)amide group showed reversible thermoresponsive phase separation in an aqueous solution. The PSQs formed by the co-condensation of such silane coupling reagents, the feed mole ratio of which were changed, also showed the thermoresponsive aggregation at the temperatures reflected with the ratios of alkoxyethyl groups.
Main text In 2009, the Consultative Committee for Ionizing Radiation (CCRI) approved its first supplementary comparison, to be organized by the ENEA (as the pilot laboratory), for the measurement of the alpha and beta particle surface (i.e. 2 solid angle) emission rate from large area sources of the type used for calibrating surface contamination monitors. Five sources were disseminated to the twenty-three participating laboratories consisting of one each of 241Am, 14C, 147Pm and 90Sr for emission rate measurements, with one additional 90Sr source for the evaluation of source uniformity. Measurements of the radionuclide activity and radionuclidic purity were also made although not strictly required. This report describes the organization of this comparison and the material and measurement methods used. The proposed supplementary comparison reference values (SCRV) for each of the comparison measurands are given, together with the Degrees of Equivalence and their associated uncertainties for each participating laboratory. The results of this supplementary comparison may be used as evidence by participating National Metrology Institutes (NMIs) and Designated Institutes (DIs) when submitting calibration and measurement capabilities (CMCs) for the given radionuclides for similar types of large area sources; this is an important aspect of this comparison, given that only one other international supplementary comparison for surface emission rates had been organized before. To reach the main text of this paper, click on Final Report . Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/ . The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
<div>Abstract<p>Sodium orthovanadate (vanadate) inhibits the DNA-binding activity of p53, but its precise effects on p53 function have not been examined. Here, we show that vanadate exerts a potent antiapoptotic activity through both transcription-dependent and transcription-independent mechanisms relative to other p53 inhibitors, including pifithrin (PFT) α. We compared the effects of vanadate to PFTα and PFTμ, an inhibitor of transcription-independent apoptosis by p53. Vanadate suppressed p53-associated apoptotic events at the mitochondria, including the loss of mitochondrial membrane potential, the conformational change of Bax and Bak, the mitochondrial translocation of p53, and the interaction of p53 with Bcl-2. Similarly, vanadate suppressed the apoptosis-inducing activity of a mitochondrially targeted temperature-sensitive p53 in stable transfectants of SaOS-2 cells. In radioprotection assays, which rely on p53, vanadate completely protected mice from a sublethal dose of 8 Gy and partially from a lethal dose of 12 Gy. Together, our findings indicated that vanadate effectively suppresses p53-mediated apoptosis by both transcription-dependent and transcription-independent pathways, and suggested that both pathways must be inhibited to completely block p53-mediated apoptosis. Cancer Res; 70(1); 257–65</p></div>
Abstract There is increasing interest in nanostructures and in the molecular design of building blocks which self-assemble into nanoscaled intelligent materials. We outline a method for controlling the nanostructures of amphiphilic nonapeptides by changing the pH of the aqueous medium. A lysine residue on the hydrophilic face of the peptide plays a critical role as a morphology-control unit. This self-assembling peptide may, therefore, find application as a template for peptide-directed biomineralization.
