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Peripheral benzodiazepine binding sites on striated muscles of the rat: Properties and effect of denervation
1985
In order to test the hypothesis that peripheral benzodiazepine binding sites mediate some direct effects of benzodiazepines on striated muscles, the properties of specific 3H-Ro 5-4864 binding to rat biceps and rat diaphragm homogenates were investigated. In both tissues a single population of sites was found with a KD value of 3 nmol/l. The density of these sites in both muscles was higher than the density in rat brain, but was considerably lower than in rat kidney. Competition experiments indicate a substrate specificity of specific 3H-Ro 5-4864 binding similar to the properties already demonstrated for the specific binding of this ligand to peripheral benzodiazepine binding sites in many…
Visceral obesity and metabolic syndrome: two faces of the same medal?
2009
In this review, we have analyzed the role of visceral obesity in the occurrence of metabolic syndrome (MetS). MetS is a common metabolic disorder that has been related recently to the increasing prevalence of obesity. The disorder is defined in various ways, but in the near future a new definition(s) should be applicable worldwide. The pathophysiology has been largely attributed, in the past years, to insulin resistance, although several epidemiological and pathophysiological data now indicate visceral obesity as a main factor in the occurrence of all the components of MetS. In view of this, relationships among visceral obesity, free fatty acids, dyslipidemia and insulin resistance have bee…
Sympathetic Nerve Stimulation on the perfused rat heart. Affinities of N-methylatropine and pirenzepine at pre- and postsynaptic muscarine receptors.
1982
Rat isolated hearts with the sympathetic nerves attached were perfused with (-)-3H-noradrenaline in order to label the storage vesicles of the adrenergic nerves. Release was induced either by electrical stimulation of the nerves (3 Hz, 1 min) or by perfusion with high K+ solution (54 mM). The overflow of 3H-noradrenaline and its metabolites was determined by liquid scintillation counting after separation of the compounds by column chromatography. The experimental conditions ensured a minor contribution of 3H-metabolites to the evoked total tritium overflow. The release of 3H-noradrenaline evoked by nerve stimulation or high K+ solution was decreased in the presence of the muscarinic agonist…
Radiolucent Carbon Fiber–Reinforced Pedicle Screws for Treatment of Spinal Tumors: Advantages for Radiation Planning and Follow-Up Imaging
2016
Objective Surgical treatment of spinal tumors regularly includes spinal instrumentation with pedicle screws. Most modern pedicle screws are made of titanium alloy, which is associated with artifacts on postoperative imaging such as computed tomography and/or magnetic resonance imaging. These artifacts hamper radiation treatment planning and execution and follow-up imaging. Recently, carbon fiber–reinforced polyetheretherketone (CFRP) implants became available for posterior instrumentation with the aim to reduce imaging artifacts by implants. Methods Patients harboring spinal tumors underwent posterior stabilization using CFRP pedicle screws. Postoperative imaging was evaluated for implant a…
Suture Materials: Do They Affect Fistula and Stricture Rates in Flap Urethroplasties?
2003
<i>Introduction:</i> The effect of suture materials on urethroplasty complications is debated. Indeed, materials with a delayed absorption might either reduce the incidence of fistulas by ensuring a prolonged approximation of neo-urethral edges or increase the risk of urethral strictures due to a prolonged tissue reaction during suture absorption. We retrospectively evaluated the role of suture materials in the complication rate of urethroplasty procedures performed in our institution over a 10-year period. <i>Patients and Methods:</i> Three hundred and thirty-six boys undergoing a flap procedure (parameatal based, preputial tube, or onlay preputial flap) for hypospa…
Low vitamin K1 intake in haemodialysis patients
2017
Background & aims Vitamin K acts as a coenzyme in the γ-carboxylation of vitamin K-dependent proteins, including coagulation factors, osteocalcin, matrix Gla protein (MGP), and the growth arrest-specific 6 (GAS6) protein. Osteocalcin is a key factor for bone matrix formation. MGP is a local inhibitor of soft tissue calcification. GAS6 activity prevents the apoptosis of vascular smooth muscle cells. Few data on vitamin K intake in chronic kidney disease patients and no data in patients on a Mediterranean diet are available. In the present study, we evaluate the dietary intake of vitamin K1 in a cohort of patients undergoing haemodialysis. Methods In this multi-centre controlled observati…
Stepwise Lateral Extension of Phenyl‐Substituted Linear Polyphenylenes
2019
Polyphenylenes (PPs) are unique polymers showing high mechanical strength and chemical stability, and having potential applications, for example, in proton transfer and gas‐separation membranes. Moreover, phenyl‐substituted linear PPs can serve as precursors for bottom‐up syntheses of graphene nanoribbons (GNRs), a new class of nanoscale carbon materials that appear promising for nanoelectronics. Notably, lateral extensions of linear PPs with appropriate “branched” phenyl substituents, that is, avoiding spatial overlap of benzene rings in their projections into a plane, can lead to wider GNRs with modulated electronic and optical properties. GNRs with widths up to ≈2 nm are obtained, but sy…
Sunscreen Products as Emerging Pollutants to Coastal Waters
2013
A growing awareness of the risks associated with skin exposure to ultraviolet (UV) radiation over the past decades has led to increased use of sunscreen cosmetic products leading the introduction of new chemical compounds in the marine environment. Although coastal tourism and recreation are the largest and most rapidly growing activities in the world, the evaluation of sunscreen as source of chemicals to the coastal marine system has not been addressed. Concentrations of chemical UV filters included in the formulation of sunscreens, such as benzophehone 3 (BZ-3), 4-methylbenzylidene camphor (4-MBC), TiO2 and ZnO, are detected in nearshore waters with variable concentrations along the day a…
Nuevos métodos de resolución del problema de secuenciación de proyectos con recursos limitados.
2002
El Problema de Secuenciación de Proyectos con Recursos Limitados (RCPSP) está considerado como el problema básico más importante dentro de la secuenciación con recursos limitados. Entre sus aplicaciones prácticas podemos citar la construcción de edificios, la planificación de la producción y el desarrollo de grandes sistemas de transporte y energía. Dado que es la base de numerosos problemas de secuenciación, cualquier avance en la resolución de este problema puede repercutir rápidamente en la resolución de muchos otros problemas. El RCPSP consiste en realizar un proyecto o conjunto de actividades sujetas a dos tipos de restricciones. Por una parte, las relaciones de precedencia fuerzan a a…
Algunas aplicaciones de la geometría estocástica en proceso digital de imágenes
2003
La información en forma de imagen es muy frecuente en muchos campos de la ciencia. En Medicina es particularmente importante debido a que muchos diagnósticos se realizan en base a imágenes. Notar la gran cantidad de técnicas de obtención de imagen existentes en este campo. El experto en Medicina examina las imágenes y toma decisiones.El Proceso de Imagen tiene como objetivo la mejora de la imagen eliminando las características que impiden su interpretación o bien realzando aquellas otras que la facilitan. El paso siguiente es la interpretación por medio de una descripción. En este trabajo se han empleado técnicas de proceso de imagen aplicadas a dos tipos de imágenes oftalmológicas.El prime…