Search results for "Tatin"

Electrochemical determination of the stability of complexes formed by proton-ionizable ligands of 3,5-disubstituted 1H-pyrazole with phenethylamine

1999

The application of two extreme models for diffusion in two-component systems to electrochemically determine equilibrium constants is discussed. The application of cyclic voltammetric, diferential pulse and rotating-disc electrode voltammetric data to elucidate the stoichiometry and formation constant of complex species by applying a generalization of the molar-ratio method is described. Molar-ratio experiments permit the distinction between the limiting diffusive regimes. The values of the equilibrium stability constants for complexation of phenethylamine and phenethylammonium ions by a 26-membered dioxotetraester crown of 3,5-disubstituted 1H-pyrazole as free ligand 1[L] and as dipyrazolat…

Synthesis, crystallographic and electrochemical study of ethynyl[2.2]paracyclophane derived cobalt metallatetrahedranes

2012

Abstract A series of alkynyl cobalt complexes [Co2(μ-η2-HCC–PCP)(CO)6−nLn] [n = 0 (2); n = 2, L2 = dppa (3), dppm (4), dcpm (6), 2 P(OPh)3 (7)] and [Co2(CO)4L2]2(μ-η2:μ-η2-HCC–PCP–CCH)] (L2 = dppm (8), dcpm (9); (PCP = [2.2]paracyclophane) has been prepared and characterized. The molecular structures of 3 and 4, as well as that of [Co2(CO)4(μ-CO)2(μ2-dcpm)] (5), have been determined by X-ray diffraction. Electrochemical studies (Cyclic Voltammetry, Rotating Disk Electrode) and luminescence spectroscopy have been used to evaluate the extent of the electronic communication through the PCP motif using the “Co2C2” centres as a probe. No electronic coupling between the Co2(CO)n centres via the b…

I livelli di cistatina C sono ridotti nell’infarto miocardico acuto. Effetto del polimorfismo G273A sui livelli plasmatici

2004

Livelli ridotti di cistatina C nell’infarto miocardico acuto vs. angina instabile, aneurisma aortico e controlli normali

2001

An Efficient Damping Technique for the Unstable Hysteretic Rotor Whirl by Proper Suspension Systems

2009

This paper shows as the destabilising influence of the shaft hysteresis on the supercritical rotor whirl can be efficiently counterbalanced by external dissipative sources. After calculating the steady whirling paths of the rotor and the bearing due to unbalance, the stability is checked by the Routh-Hurwitz procedure, investigating the influence of the stiffness anisotropy of the supports. A fairly interesting result is that the instability phenomena can be conveniently prevented by different suspension stiffness in the horizontal and vertical planes.

Somatostatin and Somatostatin Receptors: From Signaling to Clinical Applications in Neuroendocrine Neoplasms

2021

Neuroendocrine neoplasms (NENs) are heterogeneous neoplasms which arise from neuroendocrine cells that are distributed widely throughout the body. Although heterogenous, many of them share their ability to overexpress somatostatin receptors (SSTR) on their cell surface. Due to this, SSTR and somatostatin have been a large subject of interest in the discovery of potential biomarkers and treatment options for the disease. The aim of this review is to describe the molecular characteristics of somatostatin and somatostatin receptors and its application in diagnosis and therapy on patients with NENs as well as the use in the near future of somatostatin antagonists.

Human recombinant vasostatin-1 may interfere with cell-extracellular matrix interactions

2006

Vasostatin-1 (VS-1), the N-terminal fragment derived from the cleavage of chromogranin A (CgA), has been shown to exert several biological activities on several tissues and organs. Recently, it has been reported that human recombinant VS-1 (STA-CGA(1-78)) may alter myocardial contractility in eel, frog., and rat hearts. In this article we have explored if STA-CGA(1-78) can induce intracellular cascades interacting both with adhesion molecules and/or extracellular matrix (ECM), components, that is, involvement of the heat shock protein 90 (HSP90) and the endothelial NOS (eNOS), known to be implicated in signal transduction mechanisms affecting myocardial contractility. We used 3D cultured ad…

Relaxation induced by N-terminal fragments of chromogranin A in mouse gastric preparations.

2007

Abstract A definitive role for chromogranin A (CGA)-derived fragments in the control of the gastrointestinal smooth muscle contractility has not been yet established. The purpose of the present study was to evaluate, in vitro , the effects of the recombinant vasostatin 1–78 (VS-1), CGA 7–57 and CGA 47–66 on the mouse gastric mechanical activity, recording the changes of intraluminal pressure. VS-1, CGA 7–57 and CGA 47–66 produced concentration-dependent relaxations. Mouse anti-vasostatin-1 monoclonal antibody 5A8, recognising the region 53–57, abolished the relaxation induced by VS-1, indicating the specificity of the effect. The relaxation was significantly reduced by tetrodotoxin (TTX), b…

Miopatías tras exposición a hipolipemiantes: estudio de los mecanismos de susceptibilidad al daño muscular

2019

Los fármacos hipolipemiantes, fundamentalmente las estatinas, son uno de los grupos farmacológicos más frecuentemente prescritos en la población occidental. Los efectos adversos musculares constituyen la principal causa de abandono del tratamiento. El interés por este estudio surgió al observar la variabilidad en las complicaciones musculares que sufren los pacientes expuestos a estatinas. El objetivo principal de este trabajo es estudiar una serie de pacientes que han desarrollado una miopatía tras la exposición a hipolipemiantes, fundamentalmente a estatinas, que ha continuado tras la suspensión del fármaco, con la finalidad de caracterizar fenotipos clínicos y patológicos. Para ello, se …

Biomarcadores precoces de fracaso renal agudo tras angiografía coronaria o cirugía cardiaca en pacientes con síndrome coronario o fallo cardiaco agudo

2015

Introducción. El fracaso renal agudo es una complicación frecuente tras la cirugía cardiaca y la angiografía coronaria y tiene un marcado impacto sobre el pronóstico porque conlleva una mayor utilización de recursos, prolonga la estancia hospitalaria, aumenta la mortalidad y puede conducir a la enfermedad renal crónica. El diagnóstico de fracaso renal agudo se basa fundamentalmente en la detección del incremento de la creatinina sérica, que es tardío y no refleja adecuadamente el filtrado glomerular en el paciente agudo. En los últimos años diferentes grupos han intentado identificar nuevos marcadores para el diagnóstico temprano del fracaso renal agudo, pero aún quedan importantes cuestion…