Search results for "structures"
showing 10 items of 4815 documents
Brightness and contrast do not affect visually induced motion sickness in a passively-flown fixed-base flight simulator
2016
Abstract Background Visually Induced Motion Sickness (VIMS) or simulator sickness is often elicited by a visual stimulus that lacks the appropriate vestibular or proprioceptive feedback. In this study, we chose to investigate the effects of brightness and contrast of the visual scene on VIMS. Hypothesis We hypothesized that visual environments differing in brightness or contrast would differentially induce VIMS. The symptoms of VIMS should be most severe for the combination of high brightness and high contrast and conversely lowest for the low brightness and low contrast condition. Methods 33 healthy subjects were tested in a fixed-base flight simulator. Each subject flew in four consecutiv…
Bioactive compounds from mustard flours for the control of patulin production in wheat tortillas
2016
Abstract Patulin (PAT) is a toxic fungal metabolite produced by Penicillium, Aspergillus and Byssochlamys growing especially in fruit and cereals. PAT exhibits a number of toxic effects in animals and its presence in food is undesirable. In this study the reduction of the mycotoxin PAT produced by a strain of Penicillium expansum, on wheat tortillas was studied using volatile bioactive compounds present in the oriental and yellow mustard flour and also using the standard solution of the antifungal compound allyl isothiocyanate (AIT), developing an active packaging with two different systems of release of those bioactive compounds. Also the kinetic of volatilization of the compounds used in …
CTCF and BORIS Regulate Rb2/p130 Gene Transcription: A Novel Mechanism and a New Paradigm for Understanding the Biology of Lung Cancer
2011
Abstract Although innumerable investigations regarding the biology of lung cancer have been carried out, many aspects thereof remain to be addressed, including the role played by the retinoblastoma-related protein Rb2/p130 during the evolution of this disease. Here we report novel findings on the mechanisms that control Rb2/p130 gene expression in lung fibroblasts and characterize the effects of Rb2/p130 deregulation on the proliferative features of lung cancer cells. We revealed for the first time that in lung fibroblasts the expression of Rb2/p130 gene is directly controlled by the chromatin insulator CCCTC-binding factor, CTCF, which by binding to the Rb2/p130 gene promoter induces, and/…
CD133 expression in placenta chorioangioma presenting as a giant asymptomatic mass
2021
Background: Placental chorioangioma is the most common benign non-trophoblastic neoplasm of the placenta. Its clinical relevance lies in the size of the tumor since larger masses cause pregnancy complications, including an unfavorable neonatal outcome. Case presentation: We report the case of a 34-year-old second gravida and nullipara at the 35th week of gestation, admitted to the gynecological department for antibiotic-resistant fever. The cardiotocography performed during hospitalization showed an abnormal fetal pattern. A 2250 g newborn was delivered by cesarean section. No complications were observed during childbirth and postpartum was insignificant. On gross inspection a white fleshy …
Impaired in vivo vasculogenic potential of endothelial progenitor cells in comparison to human umbilical vein endothelial cells in a spheroid-based i…
2009
Objectives: Neovascularization represents a major challenge in tissue engineering applications since implantation of voluminous grafts without sufficient vascularity results in hypoxic cell death of implanted cells. An attractive therapeutic approach to overcome this is based on co-implantation of endothelial cells to create vascular networks. We have investigated the potential of human endothelial progenitor cells (EPC) to form functional blood vessels in vivo in direct comparison to vascular-derived endothelial cells, represented by human umbilical vein endothelial cells (HUVEC). Materials and methods: EPCs were isolated from human peripheral blood, expanded in vitro and analysed in vit…
Decreasing dietary linoleic acid promotes long chain omega-3 fatty acid incorporation into rat retina and modifies gene expression
2011
International audience; Age-related macular degeneration (AMD) may be partially prevented by dietary habits privileging the consumption of ω3 long chain polyunsaturated fatty acids (ω3s) while lowering linoleic acid (LA) intake. The present study aimed to document whether following these epidemiological guidelines would enrich the neurosensory retina and RPE with ω3s and modulate gene expression in the neurosensory retina. Rat progenitors and pups were fed with diets containing low or high LA, and low or high ω3s. After scotopic single flash and 8-Hz-Flicker electroretinography, rat pups were euthanized at adulthood. The fatty acid profile of the neurosensory retina, RPE, liver, adipose tis…
Tensile behaviour of anti-symmetric CFRP composite
2011
Abstract This paper addresses the response of a 17-ply anti-symmetric carbon/epoxy composite subjected to uniaxial tensile loading. Hashin ply damage model is adopted to describe the damage behaviour of the plies, whereas damage initiation and progression of the interfaces are characterised by mixed-mode cohesive damage model. Force-displacement curves obtained numerically and experimentally show good agreement. Results show that all laminae and interfaces experience the damage except laminae with 0o fibre. In addition, damage is concentrated at the tab and central regions of the tensile specimen. Edge delamination is observed in all interfaces.
Fast evaluation of enantioselective drug metabolism by electrophoretically mediated microanalysis: application to fluoxetine metabolism by CYP2D6.
2013
In this work, a capillary electrophoretic methodology for the enantioselective in vitro evaluation of drugs metabolism is applied to the evaluation of fluoxetine (FLX) metabolism by cytochrome 2D6 (CYP2D6). This methodology comprises the in-capillary enzymatic reaction and the chiral separation of FLX and its major metabolite, norfluoxetine enantiomers employing highly sulfated β-CD and the partial filling technique. The methodology employed in this work is a fast way to obtain a first approach of the enantioselective in vitro metabolism of racemic drugs, with the additional advantage of an extremely low consumption of enzymes, CDs and all the reagents involved in the process. Michaelis-Men…
Dynamic analysis of prestressed cables with uncertain pretension
2002
This paper deals with finite element dynamic analysis of prestressed cables with uncertain pretension subjected to deterministic excitations. The theoretical model addressed for cable modeling is a two-dimensional finite-strain beam theory, which allows us to eliminate any restriction on the magnitude of displacements and rotations. The dynamic problem is formulated by referring the motion to the inertial frame, which leads to a simple uncoupled quadratic form for the kinetic energy. The effect of the externally applied stochastic pretension is approximately described by means of an uncertain 'axial' component of stress resultant, which is assumed constant along the cable in its dead load c…
Influence of different biomaterials on the viability of Aggregatibacter actinomycetemcomitans
2011
Abstract Objectives The aim of the present in vitro study was to evaluate the effects of different biomaterials used for regenerative periodontal surgery on the growth of the periodontopathogen Aggregatibacter actinomycetemcomitans . Methods Three commercially available biomaterials of synthetic origin (hydroxyapatite/beta-tricalcium phosphate, nanostructured hydroxyapatite paste, oily calcium hydroxide suspension), a bovine-derived xenograft as well as an enamel matrix derivative (EMD) were added in different concentrations to calibrated suspensions of A. actinomycetemcomitans ATCC 43718/33384 (serotype b/c). Equal aliquots (0.1 ml) for the viability assay were taken after 5 min, 1 h, 3 h,…