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Role of genetic polymorphisms in myocardial infarction at young age
2010
Acute myocardial infarction (AMI) in young adult presents a typical pattern of risk factors, clinical, angiographic and prognostic characteristics. In the last years we demonstrated that hemorheological profile is altered in these patients in a persistent way and independently of the number of risk factors and of the extent of coronary lesions. Thus, the hyperviscosity syndrome following AMI could be considered an intrinsic characteristic of these patients. Consequently it is possible to hypothesise the presence of a genetic background at the origin of this predisposition. If this background is able to influence the risk of ischemic heart disease, this should be particularly evident in youn…
Costruzioni semplici : nove case nella campagna siciliana
2017
Il libro descrive nove case progettate da Michele Sbacchi nella campagna di Menfi. sono descritti il Il metodo e lo sviluppo dei progetti, nonchè alcune nozioni alla base di essi quali quelle di "costruzione" e "semplicità", nonchè un analisi dei luoghi. Si tratta della costa meridionale della Sicilia, tra Selinunte ed Agrigento, una campagna di grande fascino, quasi tutta coltivata con vigneti e uliveti. È quello che rimane del feudo dei Pignatelli Aragona Cortes, oggi territorio agricolo di prestigio internazionale. I progetti affrontano il rapporto tra il mosaico agrario e gli edifici, proponendo un’architettura che sia semplice nel metodo e nei rapporti tra le singole parti. Il concetto…
Four new triterpene saponins from Bupleurum rigidum L.
2018
Abstract Four previously undescribed triterpene saponins (1-4) were isolated from the EtOH/H2O extract of the aerial parts of Bupleurum rigidum, together with a known structural analogue. Their structures were elucidated by analysis of 1D-(1H, 13C) and 2D-NMR (1H-1H COSY, TOCSY, ROESY, HSQC, HMBC) spectroscopic data and mass spectrometry (ESI- and HR-ESI-MS) and by comparison with those of related metabolites. An unusual structure was characterized as 3-O-β-D-glucopyranosyl-(1 → 2)-[ β-D-glucopyranosyl-(1 → 3)]- β-D-fucopyranosyl-21-O-β-D-glucoyranosyl-3β,16β,21β,23-tetrahydroxy-13,28-epoxyolean-11-ene (1). The three other compounds shared the same sugar sequence as 1 and differed by the st…
Pressure-Induced Polymerization of Polycyclic Arene-Perfluoroarene Cocrystals: Single Crystal X-ray Diffraction Studies, Reaction Kinetics, and Desig…
2020
Pressure-induced polymerization of aromatic compounds leads to novel materials containing sp3 carbon-bonded networks. The choice of the molecular species and the control of their arrangement in the crystal structures via intermolecular interactions, such as the arene–perfluoroarene interaction, can enable the design of target polymers. We have investigated the crystal structure compression and pressure-induced polymerization reaction kinetics of two polycyclic 1:1 arene–perfluoroarene cocrystals, naphthalene/octafluoronaphthalene (NOFN) and anthracene/octafluoronaphthalene (AOFN), up to 25 and 30 GPa, respectively, using single-crystal synchrotron X-ray diffraction, infrared spectroscopy, a…
Triterpene saponins from the roots of Bupleurum spinosum Gouan
2020
Abstract Three previously undescribed triterpene saponins, and four known ones, were isolated from the EtOH/H2O extract of the roots of Bupleurum spinosum. Their structures were characterized using spectroscopic techniques including 1D and 2D NMR (1H, 13C, COSY, TOCSY, ROESY, HSQC, and HMBC) experiments and mass spectrometry as 3-O-β-D-glucopyranosyl-(1→6)-[β-D-glucopyranosyl-(1→2)]-[α-L-rhamnopyranosyl-(1→4)]-β-D-glucopyranosyl-3β,16β,23,28-tetrahydroxyolean-12-ene, 3-O-β-D-glucopyranosyl-(1→6)-[β-D-glucopyranosyl-(1→2)]-[α-L-rhamnopyranosyl-(1→4)]-β-D-glucopyranosyl-3β,16β,28-trihydroxy-23-oxoolean-12-ene, 3-O-β-D-glucopyranosyl-(1→6)-[α-L-rhamnopyranosyl(1→4)]-β-D-glucopyranosyl-3β,16β,2…
Variability of near-surface saturated hydraulic conductivity for the clay soils of a small Sicilian basin
2019
Abstract Proper characterization of saturated hydraulic conductivity, Ks, of clay soils in a hillslope or a basin is still a challenge for soil science. In this investigation, the clay soils of the Maganoce (Sicily, Italy) basin were sampled at 19 sampling sites by the BEST procedure of soil hydraulic characterization. More OM implied less compact conditions (decreasing dry soil bulk density; coefficient of determination, R2 = 0.67), more stability to water of the soil aggregates (increasing water stable aggregates; R2 = 0.83) and, consequently, higher Ks values (R2 = 0.54). Variability of Ks was lower in the steeper zones of the basin than in the flatter ones. A comparison with the Ks data…
Counterion influence on the N–I–N halogen bond
2015
A detailed investigation of the influence of counterions on the [N–I–N]+ halogen bond in solution, in the solid state and in silico is presented. Translational diffusion coefficients indicate close attachment of counterions to the cationic, three-center halogen bond in dichloromethane solution. Isotopic perturbation of equilibrium NMR studies performed on isotopologue mixtures of regioselectively deuterated and nondeuterated analogues of the model system showed that the counterion is incapable of altering the symmetry of the [N–I–N]+ halogen bond. This symmetry remains even in the presence of an unfavorable geometric restraint. A high preference for the symmetric geometry was found also in …
A new oleanane glycoside from the roots ofAstragalus caprinus
2006
A novel oleanane-type triterpene saponin (1) together with two known molecules, soyasapogenol B and astragaloside VIII were isolated from the roots of Astragalus caprinus. Their structural elucidation was performed mainly by 2D NMR techniques (COSY, TOCSY, NOESY, HSQC, HMBC) and mass spectrometry. Compound 1 was determined as 3-O-[alpha-L-rhamnopyranosyl-(1 --> 2)-beta-D-glucuronopyranosyl]-22-O-beta-D-apiofuranosyl-soyasapogenol B.
New Triterpene Saponins fromAcanthophyllum pachystegium
2004
Four new triterpenoid saponins, pachystegiosides A (1), B (2), C (3), and D (4), were isolated from the roots of Acanthophyllum pachystegium K. H. Their structures were elucidated by means of a combination of homo- and heteronuclear 2D-NMR techniques (COSY, TOCSY, NOESY, HSQC, and HMBC) and by FAB-MS. The new compounds were characterized as 3-O-{O-β-D-galactopyranosyl-(12)-O-[β-D-xylopyranosyl-(13)]-β-D-glucuronopyranosyl}quillaic acid 28-{O-β-D-xylopyranosyl-(13)-O-β-D-xylopyranosyl-(14)-O-α-L-rhamnopyranosyl-(12)-O-[3,4-di-O-acetyl-β-D-quinovopyranosyl-(14)]-β-D-fucopyranosyl}ester (1), 3-O-{O-β-D-galactopyranosyl-(12)-O-[β-D-xylopyranosyl-(13)]-β-D-glucuronopyranosyl}quillaic acid 28-{O-…
Triterpenoid saponins from Piptadeniastrum africanum (Hook. f.) Brenan
2013
One new triterpenoid saponin, named piptadeniaoside (1), along with two known saponins (2–3) have been isolated from the stem bark of Piptadeniastrum africanum. After previous isolation of flavone derivatives from this plant, new phytochemical investigations were performed for its saponin content. Their structures were established by direct interpretation of their spectral data, mainly HRESIMS, 1D NMR (1H, 13C NMR, DEPT) and 2D NMR (COSY, NOESY, HSQC and HMBC), and by comparison with the literature data.