Search results for "fibra"
showing 10 items of 172 documents
Microsomal and cytosolic epoxide hydrolases, the peroxisomal fatty acid beta-oxidation system and catalase. Activities, distribution and induction in…
1988
A number of structurally unrelated hypolipidaemic agents and certain phthalate-ester plasticizers induce hepatomegaly and proliferation of peroxisomes in rodent liver, but there is relatively limited data regarding the specific effects of these drugs on liver non-parenchymal cells. In the present study, liver parenchymal, Kupffer and endothelial cells from untreated and fenofibrate-fed rats were isolated and the activities of two enzymes associated with peroxisomes (catalase and the peroxisomal fatty acid beta-oxidation system) as well as cytosolic and microsomal epoxide hydrolase were measured. Microsomal epoxide hydrolase, cytosolic epoxide hydrolase and catalase activities were 7-12-fold…
Differential subcellular localization of endogenous and transfected soluble epoxide hydrolase in mammalian cells: evidence for isozyme variants
1999
AbstractEndogenous, constitutive soluble epoxide hydrolase in mice 3T3 cells was localized via immunofluorescence microscopy exclusively in peroxisomes, whereas transiently expressed mouse soluble epoxide hydrolase (from clofibrate-treated liver) accumulated only in the cytosol of 3T3 and HeLa cells. When the C-terminal Ile of mouse soluble epoxide hydrolase was mutated to generate a prototypic putative type 1 PTS (-SKI to -SKL), the enzyme targeted to peroxisomes. The possibility that soluble epoxide hydrolase-SKI was sorted slowly to peroxiosmes from the cytosol was examined by stably expressing rat soluble epoxide hydrolase-SKI appended to the green fluorescent protein. Green fluorescent…
Rat Cytosolic Epoxide Hydrolase
1986
Rat liver microsomal and cytosolic epoxide hydrolase may be distinguished through differences in substrate specificity: styrene 7,8-oxide is preferentially hydrolyzed by the microsomal form, while trans-stilbene oxide is the prefered substrate for cytosolic epoxide hydrolase. Large interindividual differences in the specific activity of SpragueDawley (outbred strain) liver cytosolic epoxide hydrolase were observed, varying from 2 to 77 pmol/min x mg protein. Interindividual variations were much lower for microsomal epoxide hydrolase. The specific activity of Fischer F-344 (inbred strain) liver cytosolic epoxide hydrolase varied only by a factor of 2. The specific activity of cytosolic epoxi…
High Sensitivity Refractive Index Sensor Based on Highly Overcoupled Tapered Fiber Optic Couplers
2017
In this paper, a simple and compact fiber-optic sensor based on an overcoupled tapered fiber coupler is studied. The coupler is fabricated to be operated well beyond the initial coupling cycles, where the rapid exchange of energy between outputs ports enable the fabrication of a highly sensitive device. The suitability and sensitivity of the proposed scheme is demonstrated by measuring refractive index (RI) variations of sugar concentrations in water. The device presents a linear response in terms of power transmission or wavelength shift versus RI changes. The best achieved sensitivity is 0.442 units of normalized transmission per unit of sugar concentration, with a noise detection limit o…
Long- and short-term stability of all polarization-maintaining thulium doped passively mode-locked fiber lasers with emission wavelengths at 1.95 µm …
2023
In this work, we compare the operation of a passively modelocked polarization-maintaining emission in two thulium-doped fiber lasers pumped at 1561 nm, with emission at wavelengths of 1.951 μm in one case and 2.07 μm in the other. We obtained a sequence of light pulses at 15.6 MHz, whose temporal width was 81 ps at 1.95 μm, and a sequence of light pulses at 13.1 MHz, whose temporal width was 94 ps at 2.07 μm. Finally, we also measured the long-term stability of this setup during a 24-h operation, as well as the short-term stability in a simulated harsh environment. The results confirm the superior performance of fiber laser systems with a fully polarization-maintaining design.
1.5 μm Ultrafast Fiber Lasers Of Repetition Rates From Single-Shot To GHz Range
2021
Esta tesis se centra en el estudio teórico y experimental del método de bloqueo de modos pasivo basado en espejos absorbentes saturables de semiconductor (SESAM). Este método se utiliza para desarrollar láseres de emisión pulsada ultracorta (duración de pulso desde femtosegundos hasta unos pocos picosegundos) en la banda de 1,5 $ \mu m $ que cubren una amplia gama de aplicaciones científicas e industriales. Los requisitos de frecuencia de repetición de pulsos son diversos para este tipo de láseres, en función de su aplicación. Bajas frecuencias de repetición, desde un solo disparo hasta varios kilohercios, se utilizan en aplicaciones de análisis de muestras donde los tiempos de respuesta so…
Harmonicity and minimality of oriented distributions
2004
We consider an oriented distribution as a section of the corresponding Grassmann bundle and, by computing the tension of this map for conveniently chosen metrics, we obtain the conditions which the distribution must satisfy in order to be critical for the functionals related to the volume or the energy of the map. We show that the three-dimensional distribution ofS4m+3 tangent to the quaternionic Hopf fibration defines a harmonic map and a minimal immersion and we extend these results to more general situations coming from 3-Sasakian and quaternionic geometry.
Asociación de pravastatina y fenofibrato (Pravafenix®). Estudios de seguridad
2014
Resumen Aunque el colesterol unido a lipoproteinas de baja densidad (cLDL) es el objetivo primario de tratamiento para reducir el riesgo cardiovascular, el incremento de trigliceridos y el descenso del colesterol unido a lipoproteinas de alta densidad (cHDL) constituyen el denominado riesgo cardiovascular residual. El tratamiento con estatinas asociado a fibratos es una posibilidad real de tratamiento del riesgo cardiovascular total. Sin embargo, esta asociacion puede con frecuencia asociarse a efectos adversos, especialmente musculares y hepaticos. Por sus caracteristicas farmacologicas, la asociacion de pravastatina con fenofibrato puede ser eficaz y segura, con escasos efectos secundario…
Peroxisome proliferator-activated receptors as regulators of lipid metabolism; tissue differential expression in adipose tissues during cold acclimat…
2004
Brown (BAT) and white (WAT) adipose tissues play a key role in the body energy balance orchestrated by the central nervous system. Hibernators have developed a seasonal obesity to respond to inhospitable environment. Jerboa is one of the deep hibernator originated from sub-desert highlands. Thus, this animal represents an excellent model to study cold adaptation mechanism. We report that the adipogenic factor PPARgamma exhibits a differential expression between BAT and WAT at mRNA level. A specific induction was only seen in WAT of pre-hibernating jerboa. Interestingly, PPAR beta/delta is specifically induced in BAT and brain of pre-hibernating jerboa, highlighting for the first time the po…
The geometry of N=3 AdS4 in massive IIA
2018
The geometry of the ${\cal N} = 3$, SO(4)--invariant, AdS$_4$ solution of massive type IIA supergravity that uplifts from the ${\cal N} = 3 $ vacuum of $D=4$ ${\cal N} = 8$ dyonic ISO(7) supergravity is investigated. Firstly, a $D=4$, SO(4)--invariant restricted duality hierarchy is constructed and used to uplift the entire, dynamical SO(4)--invariant sector to massive type IIA. The resulting consistent uplift formulae are used to obtain a new local expression for the ${\cal N} = 3 $ AdS$_4$ solution in massive IIA and analyse its geometry. Locally, the internal $S^6$ geometry corresponds to a warped fibration of $S^2$ and a hemisphere of $S^4$. This can be regarded as a warped generalisati…