Mesomorphic Properties of Some Sitosteryl Esters

The mesomorphic properties of some esters formed by aromatic acids with β-sitosterol are reported. It is shown that para-substituted benzoates are compounds exhibiting enantiotropic cholesteric and some smectic mesophases. Connections between the clearing points of sitosteryl esters and their homologous cholesteryl derivatives are discussed.     

Towards a proteome signature for invasive ductal breast carcinoma derived from label-free nanoscale LC-MS protein expression profiling of tumorous and glandular tissue

As more and more alternative treatments become available for breast carcinoma, there is a need to stratify patients and individual molecular information seems to be suitable for this purpose. In this study, we applied label-free protein quantitation by nanoscale LC-MS and investigated whether this approach could be used for defining a proteome signature for invasive ductal breast carcinoma. Tissue samples from healthy breast and tumor were collected from three patients. Protein identifications were based on LC-MS peptide fragmentation data which were obtained simultaneously to the quantitative information. Hereby, an invasive ductal breast carcinoma proteome signature was generated which contains 60 protein entries. The on-column concentrations for osteoinductive factor, vimentin, GAP-DH, and NDKA are provided as examples. These proteins represent distinctive gene ontology groups of differentially expressed proteins and are discussed as risk markers for primary tumor pathogenesis. The developed methodology has been found well applicable in a clinical environment in which standard operating procedures can be kept; a prerequisite for the definition of molecular parameter sets that shall be capable for stratification of patients.     

Weak C—H...N[triple‐bond]C hydrogen bonds in the structures of two poly(cyano)‐substituted ring systems

In benzene‐1,2,3‐tricarbonitrile, C₉H₃N₃, the packing of the two independent molecules is three‐dimensional and complex, involving inter alia bifurcated (C—H)₂...N systems from neighbouring CH groups. In [2.2]paracyclophane‐4,5,12,13‐tetracarbonitrile, C₂₀H₁₂N₄, the [2.2]paracyclophane systems display the usual distortions, namely lengthened C—C bonds and widened sp³ angles in the bridges, narrow angles in the six‐membered rings at the bridgehead atoms, and flattened boat conformations of the rings. The molecules are linked by a series of C—H...N interactions to form layers parallel to the ab plane.     

TG/DTG/DTA for the oxidation behavior characterization of vegetable and animal fats

TG/DTG/DTA curves can be used to estimate alimentary fats quality and antioxidants insertion efficiency. Sunflower oil obtained from Carnia hybrid and pork lard were used as matrices for the non-isothermal measurements. The first stage of non-isothermal decomposition is mostly important for the characterization of the fats thermal stability. The corresponding onset temperature is a good value for the comparison of different fats thermal stability or for the effectiveness evaluation in case of antioxidant insertion. In this study, it can be seen a considerable improvement of the fats thermal stability by adding small amounts from a natural antioxidant liquid mixture (obtained by alcoholic maceration of equal amounts of seven plants, namely: milfoil, rosemary, marjoram, thyme, lovage, oregano, and basil). Chlorophylls removal from the plant extract using two different adsorbents was accompanied by a four time decrease of the antiradical activity (measured by the DPPH method) with Sephadex LH20 and seventeen times decrease when activated carbon was used.     

Authentication of Honeys of Different Floral Origins via High-Performance Thin-Layer Chromatographic Fingerprinting

JPC – Journal of Planar Chromatography – Modern TLC - This paper explores the high-performance thin-layer chromatographic (HPTLC) fingerprinting of non-sugar constituents for the...