Search results for "fibra"
showing 10 items of 172 documents
Modulador acusto-óptico en amplitud de fibra óptica basado en ondas acústicas de flexión
2014
Se reporta un estudio experimental de la operación de un modulador acusto-óptico (MAO) de fibra óptica basado en la interacción acusto-óptica producida por ondas acústicas de flexión estacionarias. Concentramos nuestra atención en los efectos de reducir el diámetro en la fibra óptica como mecanismo para optimizar la respuesta espectral del MAO. Como caso particular reportamos un modulador de 70 ¹m de diametro con una alta profundidad de modulación (60 %), bajas perdidas por inserción (1.3 dB) y un ancho ancho de banda a 3 dB de 40 nm que opera en el rango de los megahertz. Los resultados obtenidos demuestran que el incluir fibras estrechadas se puede considerar como un grado extra de libert…
Prevention of endpoints in primary biliary cholangitis with ursodeoxycholic acid: quantifying the benefit
2020
Ursodeoxycholic acid (UDCA) is a hydrophilic bile acid with an established benefit for patients suffering from primary biliary cholangitis (PBC). It was first introduced in the 60s and took until the late 90s to demonstrate a survival benefit in large meta-cohort studies.1 Since then, UDCA is the established first-line therapy according to current guidelines.2 The benefit of UDCA is multidimensional, and patients receiving UDCA experience increased transplant-free survival, a decreased risk of hepatocellular carcinoma and potentially improved quality of life.3–5 The survival benefit is predicted by a number biochemical markers that reflect cholestasis and that are accepted surrogates of the…
New microRNA Biomarkers for Drug-Induced Steatosis and Their Potential to Predict the Contribution of Drugs to Non-alcoholic Fatty Liver Disease
2017
Background and Aims: Drug-induced steatosis is a major reason for drug failure in clinical trials and post-marketing withdrawal; and therefore, predictive biomarkers are essential. These could be particularly relevant in non-alcoholic fatty liver disease (NAFLD), where most patients show features of the metabolic syndrome and are prescribed with combined chronic therapies, which can contribute to fatty liver. However, specific biomarkers to assess the contribution of drugs to NAFLD are lacking. We aimed to find microRNAs (miRNAs) responsive to steatotic drugs and to investigate if they could become circulating biomarkers for drug induced steatosis. Methods: Human HepG2 cells were treated wi…
Investigating fibrosis and inflammation in an ex vivo NASH murine model.
2020
Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease, characterized by excess fat accumulation (steatosis). Nonalcoholic steatohepatitis (NASH) develops in 15–20% of NAFLD patients and frequently progresses to liver fibrosis and cirrhosis. We aimed to develop an ex vivo model of inflammation and fibrosis in steatotic murine precision-cut liver slices (PCLS). NASH was induced in C57Bl/6 mice on an amylin and choline-deficient l-amino acid-defined (CDAA) diet. PCLS were prepared from steatohepatitic (sPCLS) and control (cPCLS) livers and cultured for 48 h with LPS, TGFβ1, or elafibranor. Additionally, C57Bl/6 mice were placed on CDAA diet for 12 wk to receive elafibranor…
Parametrical Optomechanical Oscillations in PhoXonic Whispering Gallery Mode Resonators
2019
AbstractWe report on the experimental and theoretical analysis of parametrical optomechanical oscillations in hollow spherical phoxonic whispering gallery mode resonators due to radiation pressure. The optically excited acoustic eigenmodes of the phoxonic cavity oscillate regeneratively leading to parametric oscillation instabilities.
Protective effects of bezafibrate against elaidic acid-induced accumulation of lipid droplets in monocytic cells
2016
Some factors related to diet, such as trans fatty acids (TFA), are known to be involved in the progression of atherosclerosis in humans. Thus, the aim of our study was (i) to evaluate the effects of three dietary free fatty acids (FFA) (elaidic (EA), oleic (OA) and palmitic acid (PA)) on U937 human monocytes, and (ii) to study the eventual benefits of bezafibrate (BZF), a pan-agonist for PPAR isoforms (α, γ and δ) in U937 cells treated with FFA. Morphologic and functional changes were investigated by microscopic and flow cytometric methods. Cellular lipid content, lipid droplets and FA composition were identified and studied. All analyses were also realized in association with or without BZ…
Expert opinion on the metabolic complications of mTOR inhibitors
2018
Abstract Using mTOR inhibitors (mTORi) as anticancer drugs led to hyperglycemia (12–50%) and hyperlipidemia (7–73%) in phase-III trials. These high rates require adapted treatment in cancer patients. Before initiating mTORi treatment, lipid profile screening should be systematic, with fasting glucose assay in non-diabetic patients and HbA1C in diabetic patients. After initiation, lipid profile monitoring should be systematic, with fasting glucose assay in non-diabetic patients, every 2 weeks for the first month and then monthly. The HbA1C target is ≤ 8%, before and after treatment initiation in known diabetic patients and in case of onset of diabetes under mTORi. LDL-cholesterol targets sho…
Lack of Correlation of Plasma HDL With Fecal Cholesterol and Plasma Cholesterol Efflux Capacity Suggests Importance of HDL Functionality in Attenuati…
2018
A number of clinical findings suggested HDL-raising as a plausible approach to treat residual risk of CVD. However, lack of CVD risk reduction by elevated HDL cholesterol (HDL-C) through cholesterol ester transfer protein (CETP) inhibition and enhanced risk reduction in apolipoprotein A-I Milano (apoAI-M) individuals with low HDL-C shifted the focus from HDL-C level to HDL function. In the present study, we investigated correlations between HDL-C, HDL function, fecal cholesterol excretion, and ex vivo plasma cholesterol efflux capacity (CEC) in animal models using two HDL modulators, LXR and PPAR-α agonists. In C57Bl mice, LXR agonist, T1317, raised HDL-C by 30%, while PPAR-α agonist, fenof…
New fourfolds from F-theory
2015
In this paper, we apply Borcea-Voisin's construction and give new examples of fourfolds containing a del Pezzo surface of degree six, which admit an elliptic fibration on a smooth threefold. Some of these fourfolds are Calabi-Yau varieties, which are relevant for the $N=1$ compactification of Type IIB string theory known as $F$-Theory. As a by-product, we provide a new example of a Calabi--Yau threefold with Hodge numbers $h^{1,1}=h^{2,1}=10$.
Advanced in-fibre acousto-optics: applications
2017
En aplicaciones en áreas como sensado, telecomunicaciones o láseres, los dispositivos fabricados enteramente en fibra óptica ofrecen interesantes ventajas con respecto a aquellos fabricados en bulk. Una de las principales ventajas consiste en evitar la necesidad de extraer la luz guiada por una fibra óptica para procesar la señal en el dominio del tiempo, lo que se traduce en menores pérdidas. Por otra parte, comparados con los dispositivos de óptica en espacio libre, los dispositivos fabricados enteramente en fibra no requieren alineamiento, lo que proporciona una mayor estabilidad desde el punto de vista mecánico. Una cualidad deseable para los componentes ópticos es la habilidad de cambi…