Search results for " Aggregation"
showing 10 items of 441 documents
Origin of the integrin-mediated signal transduction. Functional studies with cell cultures from the sponge Suberites domuncula
1999
Sponges (phylum Porifera) represent the phylogenetically oldest metazoan animals. Recently, from the marine sponge Geodia cydonium a first cDNA encoding a putative integrin receptor molecule was isolated. In the present study basic functional experiments have been conducted to test the hypothesis that in sponges integrin polypeptides also function as adhesion molecules and as outside-in signaling molecules. The sponge Suberites domuncula has been used for the experiments because from this sponge only has a cell culture been established. Here we report that aggregation factor (AF)-mediated cell-cell adhesion is blocked by the RGDS peptide which is known to interact with beta integrin. Both R…
Cloning and expression of the putative aggregation factor from the marine sponge Geodia cydonium.
2001
Sponges (phylum Porifera) have extensively been used as a model system to study cell-cell interaction on molecular level. Recently, we identified and cloned the putative aggregation receptor (AR) of the sponge Geodia cydonium, which interacts in a heterophilic way with the aggregation factor (AF) complex. In the present study, antibodies against this complex have been raised that abolish the adhesion function of the enriched sponge AF, the AF-Fraction 6B. Using this antibody as a tool, a complete 1.7 kb long cDNA, GEOCYAF, could be isolated from a cDNA library that encodes the putative AF. Its deduced aa sequence in the N-terminal section comprises high similarity to amphiphysin/BIN1 sequen…
Hydrated Layer Formation on Tricalcium and Dicalcium Silicate Surfaces: Experimental Study and Numerical Simulations
2001
In this paper, an original approach is used to study the calcium silicate hydrate (C−S−H) layer formation on the surface of grains of anhydrous silicate during tricalcium and dicalcium silicate hydration from the variation of the rate of hydration with lime concentration. The effects of C−S−H nucleation and growth on the curves for the degree of reaction against time have been separated in both experimental study of the rate of hydration in controlled conditions and numerical simulation of the growth of C−S−H on a surface from a particle aggregation model. The influence of the number of nuclei and of the different growth modes has been quantified.
Impact of Demand Response Control Logic on Isolated Island's Distribution Networks
2019
The work presents the results of a study regarding the impact of some Demand Response control logics on an isolated distribution network. The proposed control is divided into precise steps in which the coordination between the general aggregator controller and the single local Energy Management Systems is developed and illustrated with details. The control is applied to the flexible loads and to the storage systems of photovoltaic plants installed at the end-users' houses and connected to the network. The study is carried out delivering a suitable network model of the island's system, with the implementation of load profiles for all the loads of the network for a total simulation time of 24…
General aggregation operators based on a fuzzy equivalence relation in the context of approximate systems
2016
Our paper deals with special constructions of general aggregation operators, which are based on a fuzzy equivalence relation and provide upper and lower approximations of the pointwise extension of an ordinary aggregation operator. We consider properties of these approximations and explore their role in the context of extensional fuzzy sets with respect to the corresponding equivalence relation. We consider also upper and lower approximations of a t-norm extension of an ordinary aggregation operator. Finally, we describe an approximate system, considering the lattice of all general aggregation operators and the lattice of all fuzzy equivalence relations.
Blue autofluorescence in protein aggregates “lighted on” by UV induced oxidation
2019
Oxidation of amino acid side chains in protein structure can be induced by UV irradiation leading to critical changes in molecular structure possibly modifying protein stability and bioactivity. Here we show, by using a combination of multiple spectroscopic techniques and Fluorescence Lifetime Imaging, that UV-light exposure induces irreversible oxidation processes in Ubiquitin structure. In particular, the growth of a new autofluorescence peak in the blue region is detected, that we attribute to tyrosine oxidation products. Blue autofluorescence intensity is found to progressively increase also during aggregation processes leading to the formation of aggregates of non-amyloid nature. Signi…
In vitro and in vivo characterization of a new organic nitrate hybrid drug covalently bound to pioglitazone.
2014
<b><i>Background/Aims:</i></b> Organic nitrates represent a group of nitrovasodilators that are clinically used for the treatment of ischemic heart disease. The new compound CLC-3000 is an aminoethyl nitrate (AEN) derivative of pioglitazone, a thiazolidinedione antidiabetic agent combining the peroxisome proliferator-activated receptor &#947; agonist activity of pioglitazone with the NO-donating activity of the nitrate moiety. <b><i>Methods:</i></b> In vitro and in vivo characterization was performed by isometric tension recording, platelet function, bleeding time and detection of oxidative stress. <b><i>Results:</i></…
Could resveratrol be a useful drug for the treatment of malignant hemopathies?
2013
Resveratrol is a poly-phenol with many beneficial effects: not only as an antioxidant, anti-inflammatory, and antiatherogenic agent, as well as a platelet aggregation inhibitor, but also as an antiproliferative and proapoptotic factor in various types of cancers. There are reviews about the mechanisms responsible for its effects in leukemia and lymphomas, emphasizing the chemosensitizing role of resveratrol, which allows overcoming the multidrug resistance of cancers. The action of resveratrol occurs preferentially on leukemic cells, and not on the normal ones. In addition, it is one of the few drugs that act on leukemic stem cells. If experimental results are promising, its application in …
Number of drugs used in secondary cardiovascular prevention and late survival in the population of Valencia Community, Spain.
2019
Abstract Background Drug treatment for secondary prevention of cardiovascular disease is recommended by guidelines, but it is not always followed in real life. This study wanted to assess the size of this gap and its impact on mortality in subjects after a cardiovascular event (MACE). Methods Patients with any of MACE in the period from January 1st 2011 to December 31st 2013, and more than one year of follow-up were selected from population of the Valencian Community. Drugs for secondary prevention were antiplatelets, renin-angiotensin system blockers and statins. Assessment of treatment was performed one year after the initial event. Mortality risk was assessed using Cox by the number of d…
Biowaiver monograph for immediate-release solid oral dosage forms: acetylsalicylic acid.
2012
A biowaiver monograph for acetylsalicylic acid (ASA) is presented. Literature and experimental data indicate that ASA is a highly soluble and highly permeable drug, leading to assignment of this active pharmaceutical ingredient (API) to Class I of the Biopharmaceutics Classification System (BCS). Limited bioequivalence (BE) studies reported in the literature indicate that products that have been tested are bioequivalent. Most of the excipients used in products with a marketing authorization in Europe are not considered to have an impact on gastrointestinal motility or permeability. Furthermore, ASA has a wide therapeutic index. Thus, the risks to the patient that might occur if a nonbioequi…