Antithrombotic activity of 12 table grape varieties. Relationship with polyphenolic profile

The synthesis of tissue factor (TF) by monocytes/macrophages activated by inflammatory agents is of utmost importance in the pathogenesis of thrombotic diseases and substances inhibiting TF synthesis represent novel and promising antithrombotics. We investigated the effect of 12 table grape varieties (white, red and black) on TF synthesis and the possible relation with the phenolic profile.     

Synthesis of ionones on solid Brønsted acid catalysts: Effect of acid site strength on ionone isomer selectivity

The effect of Brønsted acid site strength on the liquid-phase conversion of pseudoionone to ionone isomers (α-, β- and γ-ionone) was studied on resin Amberlyst 35W, silica-supported heteropolyacid (HPAS) and silica-supported triflic acid (TFAS). Catalyst acidity was probed by temperature-programmed desorption of NH₃ coupled with infrared spectra of adsorbed pyridine. The initial pseudoionone conversion rate followed the order: TFAS > Amberlyst 35W ≈ HPAS. Synthesis of the three ionone isomers occurred via a common cyclic carbocation intermediate formed from the activation of the pseudoionone molecule on Brønsted acid sites. Initial ionone mixtures containing a α:β:γ isomer distribution of about 40:20:40 were formed, irrespective of the acid site strength. But the ionone mixture composition changed with the progress of the reaction because γ-ionone was consecutively converted to α-ionone on HPAS and Amberlyst 35W, whereas the stronger acid sites of TFAS converted γ-ionone to β-ionone.     

Xanthenylacetic Acid Derivatives Effectively Target Lysophosphatidic Acid Receptor 6 to Inhibit Hepatocellular Carcinoma Cell Growth

Despite the increasing incidence of hepatocellular carcinoma (HCC) worldwide, current pharmacological treatments are still unsatisfactory. We have previously shown that lysophosphatidic acid receptor 6 (LPAR6) supports HCC growth and that 9-xanthenylacetic acid (XAA) acts as an LPAR6 antagonist inhibiting HCC growth without toxicity. Here, we synthesized four novel XAA derivatives, (±)-2-(9H-xanthen-9-yl)propanoic acid (compound 4 – MC9), (±)-2-(9H-xanthen-9-yl)butanoic acid (compound 5 – MC6), (±)-2-(9H-xanthen-9-yl)hexanoic acid (compound 7 – MC11), and (±)-2-(9H-xanthen-9-yl)octanoic acid (compound 8 – MC12, sodium salt) by introducing alkyl groups of increasing length at the acetic α-carbon atom. Two of these compounds were characterized by X-ray powder diffraction and quantum mechanical calculations, while molecular docking simulations suggested their enantioselectivity for LPAR6. Biological data showed anti-HCC activity for all XAA derivatives, with the maximum effect observed for MC11. Our findings support the view that increasing the length of the alkyl group improves the inhibitory action of XAA and that enantioselectivity can be exploited for designing novel and more effective XAA-based LPAR6 antagonists.     

Synthesis of Edible Vegetable Oils Enriched with Healthy 1,3-Diglycerides Using Crude Glycerol and Homogeneous/Heterogeneous Catalysis

Commercial edible vegetable oils in which part of their triglycerides are substituted with 1,3-diglycerides are healthier for human consumption than the original oils. This is because the human metabolism of 1,3-diglycerides is believed to occur through a distinct pathway with less probability of being deposited as fat in the body tissues. To obtain these enriched oils, conversion of triglycerides into diglycerides is carried out by glycerolysis using commercial crude glycerol containing dissolved alkali cations that homogeneously catalyze the reaction. The addition of a food production-compatible MgO as a supplementary solid basic catalyst, shortens the reaction time by half due to a combination of homogeneous and heterogeneous catalysis processes. In either homogeneously or homogeneous-heterogeneously catalyzed glycerolysis, the increase of the reaction temperature in the range of 453–493 K increases the final 1,3-diglyceride content. Furthermore, in both glycerolysis processes the triglyceride content can be decreased in more than 60% with the consequent increase of total diglycerides to 50%, 70% of which are the 1,3-isomers. The glycerolysis reaction proceeds without altering the fatty acid distribution of the original oils.     

Optimal experimental design for combinatorial problems

We discuss two experimental designs and show how to use them to evaluate difficult empirical combinatorial problems. We restrict our analysis here to the knapsack problem but comment more generally on the use of computational testing to analyze the performances of algorithms.Corresponding author. Part of this work was carried out while the author was visiting the IOE Department at University of Michigan and the CS department at Columbia University.     

Epoxy+liquid crystalline epoxy coreacted networks: II. Mechanical properties

The effect of coreacting diglycidyl ether of bisphenol F (DGEBP-F) with diglycidyl ether of 4,4′-dihydroxybiphenol (DGE-DHBP) on mechanical properties is investigated. DGE-DHBP shows a liquid crystal (LC) transition upon curing. Tensile, impact and fracture toughness test results are evaluated. Dynamic mechanical analysis is conducted to determine the effect of the DGE-DHBP component. Scanning electron microscopy of fracture surfaces shows changes in failure mechanisms compared to the pure components. The results indicate that the mechanical properties of these blended samples are significantly improved at 10-20% by weight of DGE-DHBP. This is a consequence of the rigidity of the LC component which thus provides the reinforcement.     

Inheritance in the join calculus

We design an extension of the join calculus with class-based inheritance. Method calls, locks, and states are handled in a uniform manner, using asynchronous messages. Classes are partial message definitions that can be combined and transformed by means of operators for behavioral and synchronization inheritance. We also give a polymorphic type system that statically enforces basic safety properties. Our language and its type system are compatible with the JoCaml implementation of the join calculus.     

The relationship between CO2 emissions,energy consumption and economic growth in Italy

This study examines the relationship between CO₂ emissions, energy consumption and economic growth in Italy over the period 1970–2006. Results of unit root tests show that all variables are non-stationary in their level form, but stationary in first differences form. The causal relationship between variables is examined using causality test in a vector autoregressive framework. Our empirical results show that CO₂ emissions, energy consumption and economic growth are not cointegrated. Moreover, the Toda and Yamamoto Granger non-causality test shows a bidirectional causality between CO₂ emissions and economic growth, as well as between CO₂ emissions and energy consumption. Forecast error variance decompositions evidence that the errors in real per capita GDP are mainly due to uncertainty in GDP itself, while the errors in predicting the energy consumption and the CO₂ emissions are sensitive to disturbances in the other two equations.     

Radical Scavenging Activity and LC-MS Metabolic Profiling of Petals, Stamens, and Flowers of Crocus sativus L

Radical scavenging activities of Crocus sativus petals, stamens and entire flowers, which are waste products in the production of the spice saffron, by employing ABTS radical scavenging method, were determined. At the same time, the metabolic profiles of different extract (obtained by petals, stamens and flowers) were obtained by LC-ESI-IT MS (liquid chromatography coupled with electrospray mass spectrometry equipped with Ion Trap analyser). LC-ESI-MS is a techniques largely used nowadays for qualitative fingerprint of herbal extracts and particularly for phenolic compounds. To compare the different extracts under an analytical point of view a specific method for qualitative LC-MS analysis was developed. The high variety of glycosylated flavonoids found in the metabolic profiles could give value to C. sativus petals, stamens and entire flowers. Practical Application: Waste products obtained during saffron production, could represent an interesting source of phenolic compounds, with respect to the high variety of compounds and their free radical scavenging activity.