Search results for "Helium"

Resveratrol, a polyphenolic phytoalexin present in red wine, enhances expression and activity of endothelial nitric oxide synthase.

2002

Background— Estrogens can upregulate endothelial nitric oxide synthase (eNOS) in human endothelial cells by increasing eNOS promoter activity and enhancing the binding activity of the transcription factor Sp1. Resveratrol, a polyphenolic phytoalexin found in grapes and wine, has been reported to act as an agonist at the estrogen receptor. Therefore, we tested the effect of this putative phytoestrogen on eNOS expression in human endothelial cells. Methods and Results— Incubation of human umbilical vein endothelial cells (HUVEC) and HUVEC-derived EA.hy 926 cells with resveratrol for 24 to 72 hours upregulated eNOS mRNA expression in a time- and concentration-dependent manner (up to 2.8-fold)…

Polysorbate-80 coating enhances uptake of polybutylcyanoacrylate (PBCA)-nanoparticles by human and bovine primary brain capillary endothelial cells

2000

Certain drugs such as dalargin, loperamide or tubocurarine are not transported across the blood-brain barrier (BBB) and therefore exhibit no effects on the central nervous system. However, effects on the central nervous system can be observed when these drugs are loaded onto polybutylcyanoacrylate (PBCA)-nanoparticles and coated with polysorbate 80. The mechanism by which these complexed nanoparticles cross the BBB and exhibit their effects has not been elucidated. Cultured microvessel brain endothelial cells of human and bovine origin were used as an in vitro model for the BBB to gain further insight into the mechanism of uptake of nanoparticles. With cells from these species we were able …

Computational and experimental investigation of intermolecular states and forces in the benzene-helium van der Waals complex

2003

A study of the intermolecular potential-energy surface (IPS) and the intermolecular states of the perprotonated and perdeuterated benzene–He complex is reported. From a fit to ab initio data computed within the coupled cluster singles and doubles including connected triples model for 280 interaction geometries, an analytic IPS including two- to four-body atom–atom terms is obtained. This IPS, and two other Lennard-Jones atom–atom surfaces from the literature, are each employed in dynamically exact (within the rigid-monomer approximation) calculations of J = 0 intermolecular states of the isotopomers. Rotational constants and Raman-scattering coefficients for intermolecular vibrational trans…

On the influence of the supporting frame on the nuclear response of the Helium-Cooled Lithium Lead Test Blanket Module for ITER

2006

Abstract Within the European Fusion Technology Programme, very intense research activities have been promoted on the Helium-Cooled Lithium Lead (HCLL) breeding blanket concept with the specific aim of manufacturing a Test Blanket Module (TBM) to be irradiated in ITER. HCLL-TBM is foreseen to be located in an ITER equatorial port, being housed inside a proper steel-supporting frame. In particular, since that frame has been designed to provide two cavities separated by a dividing plate and HCLL-TBM is foreseen to fill just one of them, its nuclear response could vary accordingly to the filling status of the other one, unless the dividing plate is thick enough to isolate the components housed …

P7142-AG impacts on endothelial cell activation and endothelial cell viability in vitro and impairs endothelial repair in vivo

2019

Abstract Background The endocannabinoid (eCB) 2-arachidonoylglycerol (2-AG) is a known modulator of inflammation and few studies have addressed its influence on myeloid cells in the context of atherogenesis. However, the impact of 2-AG on endothelial cell function has not been studied before. Methods Endothelial repair was studied in two treatment groups of wildtype mice following electrical denudation of the common carotid artery at a length of 3000 μm. One group received the monoacylglycerol lipase (MAGL)-inhibitor JZL184 [5 mg/kg i.p.], which impairs 2-AG degradation and thus causes elevated 2-AG levels, the other group received vehicle. The residual endothelial gap at five days in eithe…

Caspase-8 regulates TNF-alpha induced epithelial necroptosis and terminal ileitis

2011

Two groups identify the regulation of death-receptor-induced necroptosis as an epithelial intrinsic mechanism that is important for the maintenance of immune homeostasis and the prevention of intestinal inflammation in mice. Welz et al. describe an unexpected physiological function for FADD (Fas-associated protein with death domain), an adaptor protein required for death-receptor-induced apoptosis. Mice with intestinal epithelial specific knockout of FADD develop severe colon inflammation due to increased death of FADD-deficient colonic epithelial cells. Gunther et al. report a novel and unexpected function of caspase-8 in maintaining immune homeostasis in the gut. Caspase-8 expression by g…

Inhibition of proteasome function induces programmed cell death in proliferating endothelial cells.

2000

Proteolysis mediated by the ubiquitin-proteasome system has been implicated in the regulation of programmed cell death. Here we investigated the differential effects of proteasomal inhibitors on the viability of proliferating and quiescent primary endothelial cells in vitro and in vivo. Subconfluent, proliferating cells underwent carbobenzoxy-L-isoleucyl-gamma-t-butyl-L-glutamyl-L-alanyl-L-leucinal (PSI) -induced apoptosis at low concentrations (EC(50)=24 nM), whereas at least 340-fold higher concentrations of PSI were necessary to obtain the same effect in confluent, contact-inhibited cells. PSI-mediated cell death could be blocked by a caspase-3 inhibitor (Ac-DEVD-H), but not by a caspase…

Apoptosis causes lumen formation during angiogenesis in vitro.

2002

Effect of flupirtine on cell death of human umbilical vein endothelial cells induced by reactive oxygen species.

1999

Abstract Flupirtine (KATADOLON®), known as a nonopiate centrally acting analgesic drug, was tested as to its potential to prevent apoptosis of human endothelial cells induced by reactive oxygen species (ROS). It was found that Flupirtine displayed no effect on viability and cell proliferation of human umbilical vein endothelial cells (HUVEC) up to a concentration of 10 μg/mL. Apoptosis, induced by ROS and generated by hypoxanthine/xanthine oxidase (EC 1.1.3.22) (HX/XOD) or t-butyl hydroperoxide, was reduced after preincubation with Flupirtine for 3 hr by 35% and 41%, respectively. The maximal cytoprotective effect against apoptosis was observed at a drug concentration of 1 to 3 μg/mL. Flow …

Fatty acids liberated from low-density lipoprotein trigger endothelial apoptosis via mitogen-activated protein kinases.

2005

Enzymatic modification of low-density lipoprotein (LDL) as it probably occurs in the arterial intima drastically increases its cytotoxicity, which could be relevant for the progression of atherosclerotic lesions. LDL was treated with a protease and cholesterylesterase to generate a derivative similar to lesional LDL, with a high content of free cholesterol and fatty acids. Exposure of endothelial cells to the enzymatically modified lipoprotein (E-LDL), but not to native or oxidized LDL, resulted in programmed cell death. Apoptosis was triggered by apoptosis signal-regulating kinase 1 dependent phosphorylation of p38. Depletion and reconstitution experiments identified free fatty acids (FFA)…