Search results for "Acellular"
showing 10 items of 1986 documents
First Symposium of “Grupo Español de Investigación en Vesículas Extracelulares (GEIVEX)”, Segovia, 8–9 November 2012
2013
On the 8th and 9th of November, 71 scientists working in the field of extracellular vesicles from different laboratories in Spain met together in Segovia to present and discuss their research advances in this transformative and catalytic new field in translational biomedicine. (Published: 30 January 2013) Citation: Journal of Extracellular Vesicles 2013, 2 : 20256 - http://dx.doi.org/10.3402/jev.v2i0.20256
Influence of Extracellular Matrix on the Lipogenesis of Cultured White Fat Cells.
1998
Collagenase digests from subcutaneous fat tissue of new born rats were cultured on different types of collagen gel containing 50% type I collagen, on fibronectin (Fn) or on laminin (Lm). On day 6, 17% of cells on a plastic substratum differentiated and had multilocular or unilocular cytoplasmic lipid droplets (CLDs). Cells on each type of collagen and on Lm had more CLDs than those on a plastic substratum. The extent of lipogenesis showed the following decreasing order: cells on Lm (80%), on type IV+I collagen (70%), on type I collagen (52%), on type III+I collagen (36%), on type II+I collagen (32%). On day 14, most cells on Lm became unilocular fat cells. Cells on Fn showed delipidation an…
Multiparametric characterization by flow cytometry of flow-sorted subpopulations of a human hepatoma cell line useful for drug research
2004
Background Primary cultured hepatocytes are the closest model to the liver for drug research. However, to overcome its limited availability, the search for hepatic cell lines as an alternative to primary cultures is a matter of current interest. In particular, highly differentiated hepatocellular carcinomas have been proposed as in vitro tools for routine experiments in hepatotoxicity and drug metabolism. Methods Cell populations were selected by fluorescence-activated cell sorting based on low and high relative expressions of P-glycoprotein. These cell lines were characterized after 21 days in culture by multiparametric analysis with flow cytometry providing direct information on key cellu…
New functions and signaling mechanisms for the class of adhesion G protein-coupled receptors
2014
The class of adhesion G protein-coupled receptors (aGPCRs), with 33 human homologs, is the second largest family of GPCRs. In addition to a seven-transmembrane α-helix-a structural feature of all GPCRs-the class of aGPCRs is characterized by the presence of a large N-terminal extracellular region. In addition, all aGPCRs but one (GPR123) contain a GPCR autoproteolysis-inducing (GAIN) domain that mediates autoproteolytic cleavage at the GPCR autoproteolysis site motif to generate N- and a C-terminal fragments (NTF and CTF, respectively) during protein maturation. Subsequently, the NTF and CTF are associated noncovalently as a heterodimer at the plasma membrane. While the biological function …
Toxic and enzymatic activities of Vibrio vulnificus biotype 2 with respect to host specificity
1996
In this work, the enzymatic activities of selected strains of biotypes 1 and 2 of Vabrio vulnificus were analyzed by using conventional methods and the API ZYM system. The toxic activities of extracellular products (ECPs) were further evaluated by in vitro and in vivo experiments. The ECPs of both biotypes (i) showed high-level hydrolytic activities, (ii) displayed cytotoxicity for fish cell lines, and (iii) were lethal for eels. Exotoxins seem to be proteinaceous since heat treatment of ECP samples destroyed their toxicity. Only biotype 2 strains were virulent for cels, suggesting that host specificity must be related to differences in cell surface properties. Infectivity trials with other…
Effects of Anandamide and Noxious Heat on Intracellular Calcium Concentration in Nociceptive DRG Neurons of Rats
2007
As an endogenous agonist at the cannabinoid receptor CB1 and the capsaicin-receptor TRPV1, anandamide may exert both anti- and pronociceptive actions. Therefore we studied the effects of anandamide and other activators of both receptors on changes in free cytosolic calcium ([Ca2+]i) in acutely dissociated small dorsal root ganglion neurons (diameter: ≤30 μm). Anandamide (10 μM) increased [Ca2+]iin 76% of the neurons. The EC50was 7.41 μM, the Hill slope was 2.15 ± 0.43 (mean ± SE). This increase was blocked by the competitive TRPV1-antagonist capsazepine (10 μM) and in Ca2+-free extracellular solution. Neither exclusion of voltage-gated sodium channels nor additional blockade of voltage-gate…
Characterization of Acylating and Deacylating Activities of an Extracellular Phospholipase A2 in a Water-Restricted Environment
1994
The behavior of porcine pancreatic phospholipase A2 (ppPLA2) in monophasic low-water media has been explored, for the first time, in a systematic manner. It has been investigated how a number of variables can modulate both acylating and deacylating activities of the enzyme, and several interesting, unexpected results are presented. Among the most relevant, when placing ppPLA2 in the water-restricted environment, are the following: (i) it displays a remarkable alteration of its specificity toward the substrate polar head relative to all-water medium; (ii) it is quite severely inhibited by lysophosphatidylcholine (LPC), which has important implications, particularly concerning its acylation a…
Lack of correlation between trehalose accumulation, cell viability and intracellular acidification as induced by various stresses in Saccharomyces ce…
1998
A pma1-1 mutant of Saccharomyces cerevisiae with reduced H+-ATPase activity and the isogenic wild-type strain accumulated high levels of trehalose in response to a temperature upshift to 40 éC and after addition of 10% ethanol, but only modest levels in response to a rapid drop in external pH and after addition of decanoic acid. There was, however, no correlation between the absolute levels of trehalose in the stressed cells and their viability. All these treatments induced a significant decrease in intracellular pH, and surprisingly, this decrease was very similar in both strains, indicating that intracellular acidification could not be the triggering mechanism for trehalose accumulation i…
Proteomic Analyses of Human Cytomegalovirus Strain AD169 Derivatives Reveal Highly Conserved Patterns of Viral and Cellular Proteins in Infected Fibr…
2014
Human cytomegalovirus (HCMV) particle morphogenesis in infected cells is an orchestrated process that eventually results in the release of enveloped virions. Proteomic analysis has been employed to reveal the complexity in the protein composition of these extracellular particles. Only limited information is however available regarding the proteome of infected cells preceding the release of HCMV virions. We used quantitative mass spectrometry to address the pattern of viral and cellular proteins in cells, infected with derivatives of the AD169 laboratory strain. Our analyses revealed a remarkable conservation in the patterns of viral and of abundant cellular proteins in cells, infected for 2…
Plant extracellular vesicles: the safe for bioactive compounds
2021
Abstract If researchers within the field of extracellular vesicles are fascinated by the discovery of what was previously defined as cell rubbish bags and are today considered as important vehicles of biological information, it is even more fascinating to understand that each day, through the diet, we come into contact with vesicles from the plant kingdom, a safe for various compounds with different properties. This chapter will, therefore, focus on the description of studies carried out to date on vesicles originating from the plant kingdom. Above all we will describe the content of the vesicles, looking at the proteomic, lipidomic and nucleic acid composition; we will further discuss the …