Search results for "Viability assay"
showing 10 items of 279 documents
Kinetics of thrombomodulin release and endothelial cell injury by neutrophil-derived proteases and oxygen radicals
2002
Thrombomodulin is a transmembranous glycoprotein of endothelial cells. In vitro it is a marker of endothelial cell injury. In vivo the levels of serum thrombomodulin are regarded as a parameter of activity in vasculitides. The latter are pathophysiologically determined by neutrophil-derived inflammation and endothelial cell injury caused by secretion of proteases and hydrogen peroxide. It was the objective of this study to determine whether thrombomodulin is only a late marker of advanced endothelial cell injury or whether it indicates also earlier stages of cell alterations. Over 24 hr endothelial cell cultures were incubated with hydrogen peroxide or the neutrophil proteases proteinase-3,…
Biotechnical applications of small heat shock proteins from bacteria.
2012
The stress responses of most bacteria are thought to involve the upregulation of small heat shock proteins. We describe here some of the most pertinent aspects of small heat shock proteins, to highlight their potential for use in various applications. Bacterial species have between one and 13 genes encoding small heat shock proteins, the precise number depending on the species considered. Major efforts have recently been made to characterize the protein protection and membrane stabilization mechanisms involving small heat shock proteins in bacteria. These proteins seem to be involved in the acquisition of cellular heat tolerance. They could therefore potentially be used to maintain cell via…
Amyloid-Beta Induces Different Expression Pattern of Tissue Transglutaminase and Its Isoforms on Olfactory Ensheathing Cells: Modulatory Effect of In…
2021
Abstract Alzhèimer Disease (AD) is characterized by protein aggregates in the brain, including amyloid-beta (Aβ), a substrate for tissue transglutaminase (TG2). We assessed the effect of full native peptide of Aβ (1–42), the fragments (25–35 and 35–25) on TG2 expression and its isoforms (Long and Short) on mouse Olfactory Ensheathing Cells (OECs). The levels of cytoskeletal proteins, Vimentin and Glial Fibrillary Acid Protein, were also studied. The effect of the pre-treatment with Indicaxanthin on cell viability, total Reactive Oxygen Species, superoxide anion and apoptotic pathway activation was assessed. Since Nestin is co-expressed in pluripotent stem cells with cyclin D1, their levels …
Viability and Stimulation of Human Stem Cells from the Apical Papilla (hSCAPs) Induced by Silicate-Based Materials for Their Potential Use in Regener…
2020
Blood clot formation in the apical third of the root canal system has been shown to promote further root development and reinforcement of dentinal walls by the deposition of mineralized tissue, resulting in an advancement from traditional apexification procedures to a regenerative endodontic treatment (RET) for non-vital immature permanent teeth. Silicate-based hydraulic biomaterials, categorized as bioactive endodontic cements, emerged as bright candidates for their use in RET as coronal barriers, sealing the previously induced blood clot scaffold. Human stem cells from the apical papilla (hSCAPs) surviving the infection may induce or at least be partially responsible for the regeneration …
Cytotoxicity of glass ionomer cements containing silver nanoparticles
2015
Background: Some studies have investigated the possibility of incorporating silver nanoparticles (NAg) into dental materials to improve their antibacterial properties. However, the potential toxic effect of this material on pulp cells should be investigated in order to avoid additional damage to the pulp tissue. This study evaluated the cytotoxicity of conventional and resin-modified glass ionomer cements (GIC) with and without addition of NAg. Material and Methods: NAg were added to the materials at two different concentrations by weight: 0.1% and 0.2%. Specimens with standardized dimensions were prepared, immersed in 400 μL of culture medium and incubated at 37°C and 5% CO2 for 48 h to pr…
Comparative Cytocompatibility and Mineralization Potential of Bio-C Sealer and TotalFill BC Sealer
2019
The aim of this study was to investigate the cytocompatibility and mineralization potential of two premixed hydraulic endodontic sealers compared with an epoxy resin-based root canal sealer. The cellular responses and mineralization capacity were studied in human periodontal ligament stem cells (hPDLSCs) that were exposed to premixed hydraulic sealers, Bio-C Sealer (Angelus, Londrí
Coptis chinensis Franch. exhibits neuroprotective properties against oxidative stress in human neuroblastoma cells.
2014
Abstract Ethnopharmacological relevance The dried rhizome of Coptis chinensis Franch. (family Ranunculaceae ) is traditionally used in Chinese medicine for the treatment of inflammatory diseases and diabetes. Recent studies showed a variety of activities of Coptis chinensis Franch. alkaloids, including neuroprotective, neuroregenerative, anti-diabetic, anti-oxidative and anti-inflammatory effects. However, there is no report on the neuroprotective effect of Coptis chinensis Franch. watery extract against tert -butylhydroperoxide ( t -BOOH) induced oxidative damage. The aim of the study is to investigate neuroprotective properties of Coptis chinensis Franch. rhizome watery extract (CRE) and …
Potassium uptake system Trk2 is crucial for yeast cell viability during anhydrobiosis
2013
Yeasts grow at very different potassium concentrations, adapting their intracellular cation levels to changes in the external environment. Potassium homeostasis is maintained with the help of several transporters mediating the uptake and efflux of potassium with various affinities and mechanisms. In the model yeast Saccharomyces cerevisiae, two uptake systems, Trk1 and Trk2, are responsible for the accumulation of a relatively high intracellular potassium content (200-300 mM) and the efflux of surplus potassium is mediated by the Tok1 channel and active exporters Ena ATPase and Nha1 cation/proton antiporter. Using a series of deletion mutants, we studied the role of individual potassium tra…
Performance of the auxotrophic Saccharomyces cerevisiae BY4741 as host for the production of IL-1β in aerated fed-batch reactor: role of ACA suppleme…
2009
Abstract Background Saccharomyces cerevisiae BY4741 is an auxotrophic commonly used strain. In this work it has been used as host for the expression and secretion of human interleukin-1β (IL1β), using the cell wall protein Pir4 as fusion partner. To achieve high cell density and, consequently, high product yield, BY4741 [PIR4-IL1β] was cultured in an aerated fed-batch reactor, using a defined mineral medium supplemented with casamino acids as ACA (auxotrophy-complementing amino acid) source. Also the S. cerevisiae mutant BY4741 Δyca1 [PIR4-IL1β], carrying the deletion of the YCA1 gene coding for a caspase-like protein involved in the apoptotic response, was cultured in aerated fed-batch rea…
Cell cycle studies on the mode of action of yeast K28 killer toxin.
1996
The virally encoded K28 killer toxin of Saccharomyces cerevisiae kills sensitive cells by a receptor-mediated process. DNA synthesis is rapidly inhibited, cell viability is lost more slowly and cells eventually arrest, apparently in the S phase of the cell cycle with a medium-sized bud, a single nucleus in the mother cell and a pre-replicated (1n) DNA content. Cytoplasmic microtubules appear normal, and no spindle is detectable. Arrest of a sensitive haploid yeast strain by alpha-factor at START gave complete protection for at least 4 h against a toxin concentration that killed non-arrested cells at the rate of one log each 2.5 h. Cells released from alpha-factor arrest were killed by toxin…