146 resultados para Standing Light-wave
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Glucocorticoid-induced tumor necrosis factor receptor (GITR) is a member of the tumor necrosis factor receptor superfamily, is expressed in T lymphocytes, and exerts an anti-apoptotic function in these cells. We reported that GITR is also highly expressed in the skin, specifically in keratinocytes, and that it is under negative transcriptional control of p21(Cip1/WAF1), independently from the cell cycle. Although GITR expression is higher in p21-deficient keratinocytes and skin, it is down-modulated with differentiation and in response to UVB. The combined analysis of keratinocytes with increased GITR expression versus normal keratinocytes and skin of mice with a disruption of the GITR gene indicates that this protein protects keratinocytes from UVB-induced apoptosis both in vitro and in vivo.
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OBJECTIVES: To investigate the effect of a change in second-hand smoke (SHS) exposure on heart rate variability (HRV) and pulse wave velocity (PWV), this study utilized a quasi-experimental setting when a smoking ban was introduced. METHODS: HRV, a quantitative marker of autonomic activity of the nervous system, and PWV, a marker of arterial stiffness, were measured in 55 non-smoking hospitality workers before and 3-12 months after a smoking ban and compared to a control group that did not experience an exposure change. SHS exposure was determined with a nicotine-specific badge and expressed as inhaled cigarette equivalents per day (CE/d). RESULTS: PWV and HRV parameters significantly changed in a dose-dependent manner in the intervention group as compared to the control group. A one CE/d decrease was associated with a 2.3 % (95 % CI 0.2-4.4; p = 0.031) higher root mean square of successive differences (RMSSD), a 5.7 % (95 % CI 0.9-10.2; p = 0.02) higher high-frequency component and a 0.72 % (95 % CI 0.40-1.05; p < 0.001) lower PWV. CONCLUSIONS: PWV and HRV significantly improved after introducing smoke-free workplaces indicating a decreased cardiovascular risk.
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This study aimed to compare the effects of 2 different prior endurance exercises on subsequent whole-body fat oxidation kinetics. Fifteen men performed 2 identical submaximal incremental tests (Incr2) on a cycle ergometer after (i) a ∼40-min submaximal incremental test (Incr1) followed by a 90-min continuous exercise performed at 50% of maximal aerobic power-output and a 1-h rest period (Heavy); and (ii) Incr1 followed by a 2.5-h rest period (Light). Fat oxidation was measured using indirect calorimetry and plotted as a function of exercise intensity during Incr1 and Incr2. A sinusoidal equation, including 3 independent variables (dilatation, symmetry and translation), was used to characterize the fat oxidation kinetics and to determine the intensity (Fat(max)) that elicited the maximal fat oxidation (MFO) during Incr. After the Heavy and Light trials, Fat(max), MFO, and fat oxidation rates were significantly greater during Incr2 than Incr1 (p < 0.001). However, Δ (i.e., Incr2-Incr1) Fat(max), MFO, and fat oxidation rates were greater in the Heavy compared with the Light trial (p < 0.05). The fat oxidation kinetics during Incr2(Heavy) showed a greater dilatation and rightward asymmetry than Incr1(Heavy), whereas only a greater dilatation was observed in Incr2(Light) (p < 0.05). This study showed that although to a lesser extent in the Light trial, both prior exercise sessions led to an increase in Fat(max), MFO, and absolute fat oxidation rates during Incr2, inducing significant changes in the shape of the fat oxidation kinetics.
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Introduction: We recently observed in a chronic ovine model that a shortening of action potential duration (APD) as assessed by the activation recovery interval (ARI) may be a mechanism whereby pacing-induced atrial tachycardia (PIAT) facilitates atrial fibrillation (AF), mediated by a return to 1:1 atrial capture after the effective refractory period has been reached. The aim of the present study is to evaluate the effect of long term intermittent burst pacing on ARI before induction of AF.Methods: We specifically developed a chronic ovine model of PIAT using two pacemakers (PM) each with a right atrial (RA) lead separated by ∼2cm. The 1st PM (Vitatron T70) was used to record a broadband unipolar RA EGM (800 Hz, 0.4 Hz high pass filter). The 2nd was used to deliver PIAT during electrophysiological protocols at decremental pacing CL (400 beats, from 400 to 110ms) and long term intermittent RA burst pacing to promote electrical remodeling (5s of burst followed by 2s of sinus rhythm) until onset of sustained AF. ARI was defined as the time difference between the peak of the atrial repolarization wave and the first atrial depolarization. The mean ARIs of paired sequences (before and after remodeling), each consisting of 20 beats were compared.Results: As shown in the figure, ARIs (n=4 sheep, 46 recordings) decreased post remodeling compared to baseline (86±19 vs 103±12 ms, p<0.05). There was no difference in atrial structure as assessed by light microscopy between control and remodeled sheep.Conclusions: Using standard pacemaker technology, atrial ARIs as a surrogate of APDs were successfully measured in vivo during the electrical remodeling process leading to AF. The facilitation of AF by PIAT mimicking salvos from pulmonary veins is heralded by a significant shortening of ARI.
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This article sets out to study the profile of Swiss administrative elites at federal level by showing how their profile has evolved in the light of what has come to be known as the wave of New Public Management (NPM), which has benefited from a very fertile ground in Switzerland. These elites correspond to a specific institutional order, in relation to specific organizational structures and workings, and have specific characteristics in terms of career paths and academic background. However, the administrative reforms that have been rolled out since the 1980s have transformed the institutional order within which executives of the federal administration evolve. This article analyses the extent to which these transformations have had an impact on the characteristics of these elites, through indicators such as academic capital, social capital, and career path within and outside the administration. The results show a slow but significant transformation in the profiles of these elites towards an increasing managerialization, reflecting that of the context in which they evolve.Points for practitioners The relationship between politics and the administration is naturally shaped by individuals but is closely dependent on the profiles of the players. They are currently undergoing a transformation in the wake of administrative reforms, and also of the changing profiles of both the political and administrative players. Gaining an insight into the slow transformation of the profiles of administrative elites therefore sheds light on the political-administrative nexus. The gradual managerialization of the administrative elite highlighted in this article also allows for a better understanding of which professional experiences, qualifications and skills are valued today within the senior civil service in Switzerland.
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Abstract The maintenance of genetic variation is a long-standing issue because the adaptive value of life-history strategies associated with each genetic variant is usually unknown. However, evidence for the coexistence of alternative evolutionary fixed strategies at the population level remains scarce. Because in the tawny owl (Strix aluco) heritable melanin-based coloration shows different physiological and behavioral norms of reaction, we investigated whether coloration is associated with investment in maintenance and reproduction. Light melanic owls had lower adult survival compared to dark melanic conspecifics, and color variation was related to the trade-off between offspring number and quality. When we experimentally enlarged brood size, light melanic males produced more fledglings but in poorer condition, and they were less often recruited in the local breeding population than those of darker melanic conspecifics. Our results also suggest that dark melanic males allocate a constant effort to raise their brood independently of environmental conditions, whereas lighter melanic males finely adjust reproductive effort in relation to changes in environmental conditions. Color traits can therefore be associated with life-history strategies, and stochastic environmental perturbation can temporarily favor one phenotype over others. The existence of fixed strategies implies that some phenotypes can sometimes display a "maladapted" strategy. Long-term population monitoring is therefore vital for a full understanding of how different genotypes deal with trade-offs.
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PURPOSE: To study VP22 light controlled delivery of antisense oligonucleotide (ODN) to ocular cells in vitro and in vivo. METHODS: The C-terminal half of VP22 was expressed in Escherichia coli, purified and mixed with 20 mer phosphorothioate oligonucleotides (ODNs) to form light sensitive complex particles (vectosomes). Uptake of vectosomes and light induced redistribution of ODNs in human choroid melanoma cells (OCM-1) and in human retinal pigment epithelial cells (ARPE-19) were studied by confocal and electron microscopy. The effect of vectosomes formed with an antisense ODN corresponding to the 3'-untranslated region of the human c-raf kinase gene on the viability and the proliferation of OCM-1 cells was assessed before and after illumination. Cells incubated with vectosomes formed with a mismatched ODN, a free antisense ODN or a free mismatched ODN served as controls. White light transscleral illumination was carried out 24 h after the intravitreal injection of vectosomes in rat eyes. The distribution of fluorescent vectosomes and free fluorescent ODN was evaluated on cryosections by fluorescence microscopy before, and 1 h after illumination. RESULTS: Overnight incubation of human OCM-1 and ARPE-19 cells with vectosomes lead to intracellular internalization of the vectosomes. When not illuminated, internalized vectosomes remained stable within the cell cytoplasm. Disruption of vectosomes and release of the complexed ODN was induced by illumination of the cultures with a cold white light or a laser beam. In vitro, up to 60% inhibition of OCM-1 cell proliferation was observed in illuminated cultures incubated with vectosomes formed with antisense c-raf ODN. No inhibitory effect on the OCM-1 cell proliferation was observed in the absence of illumination or when the cells are incubated with a free antisense c-raf ODN and illuminated. In vivo, 24 h after intravitreal injection, vectosomes were observed within the various retinal layers accumulating in the cytoplasm of RPE cells. Transscleral illumination of the injected eyes with a cold white light induced disruption of the vectosomes and a preferential localization of the "released" ODNs within the cell nuclei of the ganglion cell layer, the inner nuclear layer and the RPE cells. CONCLUSIONS: In vitro, VP22 light controlled delivery of ODNs to ocular cells nuclei was feasible using white light or laser illumination. In vivo, a single intravitreal injection of vectosomes, followed by transscleral illumination allowed for the delivery of free ODNs to retinal and RPE cells.
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The kinetics of binding of a glycolipid-anchored protein (the promastigote surface protease, PSP) to planar lecithin bilayers is studied by an integrated optics technique, in which the bilayer membrane is supported on an optical wave guide and the phase velocities of guided light modes in the wave guide are measured. From these velocities, the optical parameters of the membrane and PSP layers deposited on the waveguide are determined, yielding in particular the mass of PSP bound to the membrane, which is followed in real time. From a comparison of the binding rates of PSP and PSP from which the lipid moiety has been removed, it is shown that the lipid moiety plays a key role in anchoring the protein to the membrane. Specific and nonspecific binding of antibodies to membrane-anchored PSP is also investigated. As little as a fifth of a monolayer of PSP is sufficient to suppress the appreciable nonspecific binding of antibodies to the membrane.
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HIV escape in the central nervous system (CNS) despite undetectable viral load in the plasma has been observed and may contribute to HIV-associated neurocognitive disorders. Favouring the use of HIV drugs with a good penetration into the CNS has been advocated, leading to the establishment of the CNS penetration-effectiveness (CPE) score. However, the relevance of this score is not fully established. Ciccarelli et al. compared two versions of the CPE scores in their capacity to predict cognitive dysfunction in HIV-infected individuals. The revised CPE score, but not the original one, showed an improved association with cognitive impairment. Prospective studies are warranted to assess the validity of the CPE score.
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Using the transit pulse method, we have determined compressional wave velocities of rocks from various geological units belonging to the Penninic zone along the NFP20-West profiles of the Swiss western Alps. The velocities have been measured at confining pressures up to 400 MPa, along three orthogonal axes defined by the macrostructure of the rocks. The samples analysed show a degree of metamorphism ranging from greenschist to eclogite facies. This collection includes schists, dolomites, gneisses and ophiolitic rocks. The mean velocities range from 5.9 km/s for a quartzitic calcschist to 7.9 km/s for an eclogitic metagabbro. The velocity anisotropy is as high as 20 %. The range of acoustic impedance is wide, from 15 to 27 10(6) kg/m2s. From these measurements, normal incident reflection coefficients for likely rock assemblages within and between geological units were estimated in order to interpret zone of the strong reflections recorded along the seismic profiles. Reflection coefficients as high as 0.17 could be determined.
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We present the optical properties of Na0.7CoO2 single crystals, measured over a broad spectral range as a function of temperature (T). The capability to cover the energy range from the far-infrared up to the ultraviolet allows us to perform reliable Kramers-Kronig transformation, in order to obtain the absorption spectrum (i.e., the complex optical conductivity). To the complex optical conductivity we apply the generalized Drude model, extracting the frequency dependence of the scattering rate (Gamma) and effective mass (m*) of the itinerant charge carriers. We find that Gamma(omega) at low temperatures and for similar to omega. This suggests that Na0.7CoO2 is at the verge of a spin-density-wave metallic phase.
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Objectifs. - Le DSM-5 donne une définition du symptôme psychotique indépendante de tout concept depsychose. Chez les patients dépressifs, la présence d'hallucination ou d'idée délirante, quelle que soit leurforme clinique, conduit en principe à diagnostiquer une dépression psychotique et à prescrire des neurolep-tiques. Les symptômes psychotiques sont subdivisés par le DSM en « congruents » ou « non congruents » àl'humeur. Nous discutons de la pertinence d'une catégorie de symptômes psychotiques « atypiques », peuévocateurs d'une psychose au sens classique du terme. Méthode. - Discussion de la définition opérationnelle des symptômes psychotiques du DSM, étude d'unesérie de 16 patients chez qui un diagnostic de dépression psychotique a été posé. Résultats. - Sur les 16 patients, deux seulement présentaient des symptômes psychotiques classiques, évo-cateurs d'une psychose. Chez les autres, le diagnostic reposait sur la présence de symptômes très atypiques,comme des hallucinations visuelles par exemple.