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121.
Benoit Mesnard Maxime Leroy James Hunter Delphine Kervella Marc-Olivier Timsit Lionel Badet Pascal Glemain Emmanuel Morelon Fanny Buron Moglie Le Quintrec-Donnette Vincent Pernin Marc Ladriere Sophie Girerd Christophe Legendre Antoine Sicard Laeticia Albano Stephane De Vergie Clarisse Kerleau Thomas Prudhomme Jérôme Rigaud Diego Cantarovich Gilles Blancho Georges Karam Magali Giral Simon Ville Julien Branchereau For the Données Informatisées et VAlidées en Transplantation/Computerized VAlidated Data in Transplantation Consortium Affiliations† 《BJU international》2022,129(2):225-233
122.
Elastin peptides have been shown to produce many biological effects on various cell types, including an endothelium- and NO-dependent vasodilatation mediated by extracellular calcium influx and intracellular calcium elevation. Under normal concentration of extracellular glucose, the vasodilatory effect is observed in adult rats and is lost with age. Here, we have studied the consequences of extracellular glucose level changes on these effects triggered by elastin peptides (10(-4)-10(-3) mg ml(-1)), on 6- and 30-month-old rats, using the tension myography and the patch-clamp techniques. Our results show that low (0 mM) or high (33 mM) extracellular glucose concentrations abolish the extracellular calcium influx induced, under normal glucose level (11 mM), by the elastin peptides in cultured human endothelial cells. Also, low or high glucose abolish the vasodilatory action of elastin peptides observed on aorta rings from adult rats under normal glucose concentration. On the contrary, a dilation of aged rat aorta is observed in the presence of elastin peptides and high glucose, whereas such dilation is not observed when the elastin peptides are added in the presence of normal glucose concentration. In aging, a restoration by high glucose of the NO-dependent vasodilatation induced by elastin peptides could enhance the production of damaging peroxynitrite, potentially altering the structure and function of the blood vessels. These results could be of importance in the evaluation and treatment of aged patients with pathophysiological dysregulations of the circulating glucose level, such as in diabetes, age-related glucose intolerance, or low glucose levels caused by inappropriate glucose control treatments. 相似文献
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It has been proposed that an internal representation of body vertical has a prominent role in spatial orientation. This investigation investigated the ability of human subjects to accurately locate their longitudinal body axis (an imaginary straight body midline running from head to toes) while free-floating in microgravity. Subjects were tested in-flight, as well as on ground in normal gravity in both the upright and supine orientations to provide baseline measurements. The subjects wore a goggle device and were in total darkness. They used knobs to rotate two luminous lines until they were parallel to the subjective direction of their longitudinal body axis, in the roll (right/left) and the pitch (forward/backward) planes. Results showed that the error between the perceived and the objective direction of the longitudinal body axis was significantly larger in microgravity than in normal gravity. This error in this egocentric frame of reference is presumably due to the absence of somatosensory cues when free-floating. Mechanical pressure on the chest using an airbag reduced the error in perception of the longitudinal body axis in microgravity, thus improving spatial orientation. 相似文献
126.
Mouly E Dorival C Pflumio F Baillou C Coulombel L Levy Y Lemoine FM Klatzmann D Marodon G 《Molecular immunology》2007,44(4):267-275
In humans, the CD4 molecule is expressed on a subset of T-cells and at various levels on myeloid and lymphoid cells. The mechanisms regulating human CD4 gene expression are yet poorly understood. We speculated that the CD4 silencer, which operates in CD8+ T-cells to repress CD4 expression, could be responsible for CD4 repression in human lymphoid non-T-cells. To test this possibility, we used lentiviral vectors carrying CD4 regulatory sequences, with or without the silencer element, to express an eGFP reporter gene. We observed that (i) in the absence of the silencer element, eGFP expression was detected in CD34+-derived B- and NK-cells that otherwise lacked endogenous CD4 mRNA, indicating active repression of the CD4 regulatory sequences and (ii) the addition of the CD4 silencer could repress eGFP expression in these same cells, as well as in human B-cells generated in vivo in NOD/SCID mice. Collectively, our results suggest that beyond its well-characterized function in T-cells, the CD4 silencer also regulates CD4 gene expression in human lymphoid non-T-cells. 相似文献
127.
Seasonal variations of insect population sizes are often dramatic, particularly in temperate regions and at altitudes where the climatic conditions are unfavorable to insect development during the winter. Decline of population size (or bottlenecks) and founder events may reduce the genetic variability and may create genetic differentiation between populations by drift and founder effects, but this reduction of genetic diversity is strongly influenced by gene flow between populations. In this study, we determined the population genetic structure for two stomoxyine species (Diptera: Muscidae), Stomoxys calcitrans (L.) and Stomoxys niger niger Macquart, which co-occur in dairy barns along an altitudinal gradient on La Réunion island. Using microsatellite markers, we quantified the genetic variation within and among populations for different altitudes. This study displays that, contrary to expectations, genetic diversity is not correlated with altitude and that genetic differentiation is not larger among high-altitude populations than among low-altitude populations. These results attest to the small drift and founder effects in high-altitude populations despite drastic decreases in population size during the winter. Furthermore, at the island scale, the populations of S. calcitrans were slightly differentiated, but those of S. niger niger were not. Together, the results revealed large levels of gene flow on La Réunion Island despite the dramatic geographic barriers, and they emphasize the importance of considering agricultural practices to restrict the dispersal of stomoxyines. 相似文献
128.
Defuentes G Bladé JS Berets O 《The New England journal of medicine》2007,357(15):1557; author reply 1557-1557; author reply 1558
129.
Stereo vision enhances the learning of a catching skill 总被引:1,自引:0,他引:1
Mazyn LI Lenoir M Montagne G Delaey C Savelsbergh GJ 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2007,179(4):723-726
The aim of this study was to investigate the contribution of stereo vision to the acquisition of a natural interception task. Poor catchers with good (N = 8; Stereo+) and weak (N = 6; Stereo-) stereo vision participated in an intensive training program spread over 2 weeks, during which they caught over 1,400 tennis balls in a pre-post-retention design. While the Stereo+ group improved from a catching percentage of 18% to 59%, catchers in the Stereo- group did not significantly improve (from 10 to 31%), this progress being indifferent from a control group (N = 9) that did not practice at all. These results indicate that the development and use of of compensatory cues for depth perception in people with weak stereopsis is insufficient to successfully deal with interceptions under high temporal constraints, and that this disadvantage cannot be fully attenuated by specific and intensive training. 相似文献
130.