Identification of cardiac organ damage in arterial hypertension: insights by echocardiography for a comprehensive assessment

: Arterial hypertension, a widespread disease, whose prevalence increases with age, represents a major risk factor for cardiovascular events, causing damage in several organs, including the heart. In this context, echocardiography has a clear and pivotal role, being able to assess cardiac morphology and detect haemodynamic changes induced by this disease. 2018 European Society of Cardiology/European Society of Hypertension guidelines on AH identified main echo parameters such as left ventricular mass, relative wall thickness and left atrial volume, for detecting cardiac organ damage. The present review highlights the advantage of additional echocardiographic parameters such as diastolic measurement and both thoracic and abdominal aortic dimensions. An overlook on aortic valve should also be suggested to detect aortic regurgitation and stenosis, both frequent complications in hypertensive patients. In this kind of comprehensive assessment, the combination of standard and advanced echocardiography (speckle tracking echocardiography and, with a lesser extent, three-dimensional echocardiography) could be considered to improve the diagnostic accuracy, stratify prognosis and address management in arterial hypertension

Synthesis of imidazolidin-2-one-4-carboxylate and of (tetrahydro)pyrimidin- 2-one-5-carboxylate via an efficient modification of the Hofmann rearrangement

A mild and efficient methodology for the rearrangement of protected asparagine and protected glutamine is reported; good results are obtained with a wide selection of protecting groups. © The Royal Society of Chemistry

A network of small molecules connected by cross-linked NH bonds

The synthesis of the small pseudopeptide Boc-L-Phe-D-Imz-OBn (Imz = imidazolidin-2-one-4-carboxylate) is reported. Crystallization of this peptide from methanol, ethanol, and isopropanol leads to isostructural solvates when the solvent is methanol or ethanol with a peptide/solvent ratio of 2:1 and to an unsolvated polymorph in the case of isopropanol. The solvate peptide crystallizes forming infinite chains with the monomers in parallel orientation connected by a single hydrogen bond. The chains are arranged in antiparallel direction and cross-linked through the NH group of the imidazolidin heterocycle with formation of a stable two-dimensional (2D) network. Crystals from isopropanol form a different 2D network. The degree of order in the crystal assembly decreases from methanol and ethanol solvates to the unsolvated pseudopeptide grown from isopropanol. Quantum chemical calculations at the HF/6-31G* level of ab initio MO theory, carried out on the two different packings, show a slight preference for the unsolvated packing. ©2009 American Chemical Society

Efficient Cluster-Based Catalysts for Asymmetric Hydrogenation of α-Unsaturated Carboxylic Acids.

The new clusters [H(4) Ru(4) (CO)(10) (μ-1,2-P-P)], [H(4) Ru(4) (CO)(10) (1,1-P-P)] and [H(4) Ru(4) (CO)(11) (P-P)] (P-P=chiral diphosphine of the ferrocene-based Josiphos or Walphos ligand families) have been synthesised and characterised. The crystal and molecular structures of eleven clusters reveal that the coordination modes of the diphosphine in the [H(4) Ru(4) (CO)(10) (μ-1,2-P-P)] clusters are different for the Josiphos and the Walphos ligands. The Josiphos ligands bridge a metal-metal bond of the ruthenium tetrahedron in the "conventional" manner, that is, with both phosphine moieties coordinated in equatorial positions relative to a triangular face of the tetrahedron, whereas the phosphine moieties of the Walphos ligands coordinate in one axial and one equatorial position. The differences in the ligand size and the coordination mode between the two types of ligands appear to be reflected in a relative propensity for isomerisation; in solution, the [H(4) Ru(4) (CO)(10) (1,1-Walphos)] clusters isomerise to the corresponding [H(4) Ru(4) (CO)(10) (μ-1,2-Walphos)] clusters, whereas the Josiphos-containing clusters show no tendency to isomerisation in solution. The clusters have been tested as catalysts for asymmetric hydrogenation of four prochiral α-unsaturated carboxylic acids and the prochiral methyl ester (E)-methyl 2-methylbut-2-enoate. High conversion rates (>94 %) and selectivities of product formation were observed for almost all catalysts/catalyst precursors. The observed enantioselectivities were low or nonexistent for the Josiphos-containing clusters and catalyst (cluster) recovery was low, suggesting that cluster fragmentation takes place. On the other hand, excellent conversion rates (99-100 %), product selectivities (99-100 % in most cases) and good enantioselectivities, reaching 90 % enantiomeric excess (ee) in certain cases, were observed for the Walphos-containing clusters, and the clusters could be recovered in good yield after completed catalysis. Results from high-pressure NMR and IR studies, catalyst poisoning tests and comparison of catalytic properties of two [H(4) Ru(4) (CO)(10) (μ-1,2-P-P)] clusters (P-P=Walphos ligands) with the analogous mononuclear catalysts [Ru(P-P)(carboxylato)(2) ] suggest that these clusters may be the active catalytic species, or direct precursors of an active catalytic cluster species