Search results for "ACTIVATION"
showing 10 items of 2079 documents
Protein kinase C promotes angiogenic activity of human endothelial cells via induction of vascular endothelial growth factor
2008
Aims Protein kinase C (PKC) plays an important role in the regulation of angiogenesis. However, downstream targets of PKC in endothelial cells are poorly defined. Methods and results mRNA expression of vascular endothelial growth factor (VEGF) was analysed by quantitative real-time RT-PCR in human umbilical vein endothelial cells (HUVEC) and HUVEC-derived EA.hy 926 cells. siRNA was used to knockdown PKC isoforms and VEGF. Matrigel tube formation assay was used to analyse the angiogenic activity of endothelial cells. Phorbol-12-myristate-13-acetate (PMA) enhanced the ability of HUVEC to organize into tubular networks when plated on Matrigel, a phenomenon that could be prevented by PKC inhibi…
Modification of xenogenic bone substitute materials - effects on the early healing cascadein vitro
2013
Introduction Initial platelet activation with subsequent cytokine release at the defect site plays a crucial role in tissue integration. The aim of this study was to evaluate the influence of topographic and biomimetic collagen modifications of a xenogenic bone substitute material (BSM) on in vitro platelet activation and cytokine release. Material and Methods Three types of xenogenic BSM were used. Two BSM with different levels of granularity (large granule BSM [XBSM/L], small granule BSM [XBSM/S]) and a BSM with collagen (XBSM/C). All three samples were incubated with platelet concentrate of four healthy volunteers at room temperature for 15 min. For all groups, highly thrombogenic collag…
Biochemistry and pharmacology of novel anthranilic acid derivatives activating heme-oxidized soluble guanylyl cyclase.
2005
The heme-enzyme soluble guanylyl cyclase (sGC) is an ubiquitous NO receptor, which mediates NO downstream signaling by the generation of cGMP. We studied the mechanism of action of the anthranilic acid derivatives 5-chloro-2-(5-chloro-thiophene-2-sulfonylamino-N-(4-(morpholine-4-sulfonyl)-phenyl)-benzamide sodium salt (HMR1766) (proposed international nonproprietary name, ataciguat sodium) and 2-(4-chloro-phenylsulfonylamino)-4,5-dimethoxy-N-(4-(thiomorpholine-4-sulfonyl)-phenyl)-benzamide (S3448) as a new class of sGC agonists. Both compounds activated different sGC preparations (purified from bovine lung, or crude from human corpus cavernosum) in a concentration-dependent and quickly reve…
Activación plaquetaria e hipercolesterolemia en la patogenia de la trombosis venosa profunda
2006
Currently it is accepted that deep vein thrombosis is a multifactorial event in which the presence of activated platelets and also plasmatic lipids seems to play a pivotal role that it is not well established in the scientific bibliography. Due to the non consensus state about these topics between the different groups working in these aspects, the topic involving deep vein thrombosis-platelets-lipids, and also their interactions, still is an interesting area of investigation, in which it is necessary to carry out studies with the aim of establishing risk factors, initial diagnostic methods and clinical assays to probe the efficacy of new therapies.
On the pathogenesis of atherosclerosis: enzymatic transformation of human low density lipoprotein to an atherogenic moiety.
1995
Combined treatment with trypsin, cholesterol esterase, and neuraminidase transforms LDL, but not HDL or VLDL, to particles with properties akin to those of lipid extracted from atherosclerotic lesions. Single or double enzyme modifications, or treatment with phospholipase C, or simple vortexing are ineffective. Triple enzyme treatment disrupts the ordered and uniform structure of LDL particles, and gives rise to the formation of inhomogeneous lipid droplets 10-200 nm in diameter with a pronounced net negative charge, but lacking significant amounts of oxidized lipid. Enzymatically modified LDL (E-LDL), but not oxidatively modified LDL (ox-LDL), is endowed with potent complement-activating c…
High pressure treatment and green tea extract synergistically control enteric virus contamination in beverages
2022
Consumers are driving food production toward the use of natural preservatives and minimal processing technologies. Green tea extract (GTE) at low concentration could be combined with high pressure processing (HPP) for reduced treatment times and quality impact on foods in a hurdle concept for synergistic effects on foodborne viral pathogens, specifically human norovirus and hepatitis A virus (HAV). Viral inactivation by HPP (at 300, 400, and 500 MPa for 5 min) combined with 3.3 mg/mL aged-GTE was initially evaluated in buffer (PBS) against murine norovirus (MNV), a culturable human norovirus surrogate, and HAV. Furthermore, human norovirus inactivation was evaluated by the novel human intes…
Activity investigation of pinostrobin towards herpes simplex virus-1 as determined by atomic force microscopy
2009
In the present study, the antiviral activity of pinostrobin towards herpes simplex virus-1 (HSV-1) was investigated by MTT assay and atomic force microscopy. Pinostrobin can inhibit HSV-1 replication with 50% effective concentration (EC(50)) of 22.71 ± 1.72 μg/ml. MTT assay showed HSV-1 was significantly inhibited when pretreated with pinostrobin, with the inhibition of 85.69 ± 2.59%. Significant changes in morphology and size of HSV-1 were observed by atomic force microscopy (AFM) in response to pinostrobin treatment. AFM topography and phase images showed that with increasing time, the envelope was shedded and damaged, finally leading to virus inactivation. With increasing concentration, …
Zizyphus lotus L. (Desf.) modulates antioxidant activity and human T-cell proliferation
2009
Abstract Background Zizyphus lotus L. (Desf.) also known as Jujube, is a deciduous shrub which belongs to Rhamnaceae family. This plant is used in Algerian traditional medicine for its anti-diabetic, sedative, analgesic, anti-inflammatory and hypoglycaemic activities. In the present study, we determined the concentrations of different vitamins (vitamin A, C and E) and fatty acids in root, stem, leaves, fruit pulp and seed of Zizyphus lotus L. (Desf.) and assessed the effects of their aqueous extracts on antioxidant status and human T-cell proliferation. Methods Aqueous filtrates from different parts, i.e, root, leaf, stem, fruit pulp and seed, of Zizyphus lotus L. (Desf.) were prepared. Vit…
Wee1 inhibition potentiates Wip1-dependent p53-negative tumor cell death during chemotherapy
2016
AbstractInactivation of p53 found in more than half of human cancers is often associated with increased tumor resistance to anti-cancer therapy. We have previously shown that overexpression of the phosphatase Wip1 in p53-negative tumors sensitizes them to chemotherapeutic agents, while protecting normal tissues from the side effects of anti-cancer treatment. In this study, we decided to search for kinases that prevent Wip1-mediated sensitization of cancer cells, thereby interfering with efficacy of genotoxic anti-cancer drugs. To this end, we performed a flow cytometry-based screening in order to identify kinases that regulated the levels of γH2AX, which were used as readout. Another criter…
Resonant activation in polymer translocation: new insights into the escape dynamics of molecules driven by an oscillating field
2010
The translocation of molecules across cellular membranes or through synthetic nanopores is strongly affected by thermal fluctuations. In this work we study how the dynamics of a polymer in a noisy environment changes when the translocation process is driven by an oscillating electric field. An improved version of the Rouse model for a flexible polymer has been adopted to mimic the molecular dynamics, by taking into account the harmonic interactions between adjacent monomers and the excluded-volume effect by introducing a Lennard–Jones potential between all beads. A bending recoil torque has also been included in our model. The polymer dynamics is simulated in a two-dimensional domain by num…