Search results for "Cytometry"

Reactive oxygen species derived from the mitochondrial respiratory chain are not responsible for the basal levels of oxidative base modifications obs…

2004

The mitochondrial electron transport chain (ETC) is the most important source of reactive oxygen species (ROS) in mammalian cells. To assess its relevance to the endogenous generation of oxidative DNA damage in the nucleus, we have compared the background (steady-state) levels of oxidative DNA base modifications sensitive to the repair glycosylase Fpg (mostly 7,8-dihydro-8-oxoguanine) in wild-type HeLa cells and HeLa rho0 cells. The latter are depleted of mitochondrial DNA and therefore are unable to produce ROS in the ETC. Although the levels of ROS measured by flow cytometry and redox-sensitive probes in rho0 cells were only 10-15% those of wild-type cells, steady-state levels of oxidativ…

Modulation of P-glycoprotein activity by novel synthetic curcumin derivatives in sensitive and multidrug-resistant T-cell acute lymphoblastic leukemi…

2016

Abstract Background Multidrug resistance (MDR) and drug transporter P-glycoprotein (P-gp) represent major obstacles in cancer chemotherapy. We investigated 19 synthetic curcumin derivatives in drug-sensitive acute lymphoblastic CCRF–CEM leukemia cells and their multidrug-resistant P-gp-overexpressing subline, CEM/ADR5000. Material and methods Cytotoxicity was tested by resazurin assays. Doxorubicin uptake was assessed by flow cytometry. Binding modes of compounds to P-gp were analyzed by molecular docking. Chemical features responsible for bioactivity were studied by quantitative structure activity relationship (QSAR) analyses. A 7-descriptor QSAR model was correlated with doxorubicin uptak…

Signaling pathways of the TREM-1- and TLR4-mediated neutrophil oxidative burst.

2008

The triggering receptor expressed on myeloid cells 1 (TREM-1) is involved in the innate inflammatory response to microbial infections. Activation and expression of TREM-1 by polymorphonuclear neutrophils (PMN) occurs in concert with Toll-like receptors (TLR) such as TLR4 for bacterial lipopolysaccharide. However, it is currently unclear how this is mediated on a molecular level. Using pharmacological inhibitors and Western blot analysis we demonstrate that phosphatidyl inositide 3-kinase, phospholipase C and the mitogen-activated kinase p38MAPK are essential for the TREM-1- and TLR4-induced oxidative burst of human PMN. The activation of protein kinase B and extracellular signal-related kin…

Thermo-setting glass ionomer cements promote variable biological responses of human dental pulp stem cells.

2017

To evaluate the in vitro cytotoxicity of Equia Forte (GC, Tokyo, Japan) and Ionostar Molar (Voco, Cuxhaven, Germany) on human dental pulp stem cells (hDPSCs).hDPSCs isolated from third molars were exposed to several dilutions of Equia Forte and Ionostar Molar eluates (1/1, 1/2 and 1/4). These eluates were obtained by storing material samples in respective cell culture medium for 24h (n=40). hDPSCs in basal growth culture medium were the control. Cell viability and cell migration assays were performed using the MTT and wound-healing assays, respectively. Also, induction of apoptosis and changes in cell phenotype were evaluated by flow cytometry. Changes in cell morphology were analysed by im…

Impact of exogenous lactate on survival and radioresponse of carcinoma cells in vitro

2009

Tumour lactate levels have been shown to correlate with high radioresistance in tumour models in vivo. The study aimed to evaluate the impact of pathophysiological extracellular lactate concentrations and acidosis on the in vitro survival and radioresponse of various cancer cell lines.HCT-116, HT29 (colorectal) and FaDu (HNSCC) carcinoma cells were studied. Lactate release rates were determined, and expression of the monocarboxylate transporter MCT1 and its cofactor CD147 were monitored by immunofluorescence and flow cytometry. Colony formation was compared for cells exposed to 20 mM exogenous lactate, acidosis (pH 6.4) and lactate plus acidosis relative to control and dose response curves …

Zinc oxide nanorod based immunosensing platform for the determination of human leukemic cells.

2019

Zinc oxide (ZnO) based nanostructures owing unique physical properties – high photoluminescence, bio- compatibility and other characteristics, therefore, they attract attention as building blocks suitable for biosensor development. In this research as a target we have used human leukemic cell line IM9 (IM9). IM9 was derived from the patient with a multiple myeloma and expressed cluster of differentiation proteins СD19 on the surface of 85–95% here investigated cancer cells. As a control sample healthy human's peripheral blood mononuclear cells (PBMC) were used and the expression of CD19 protein was found only in 5–9% of these cells. Two types of antibodies labeled by f…

Regulatory T Cells and IL-10 Independently Counterregulate Cytotoxic T Lymphocyte Responses Induced by Transcutaneous Immunization

2011

Background: The imidazoquinoline derivate imiquimod induces inflammatory responses and protection against transplanted tumors when applied to the skin in combination with a cognate peptide epitope (transcutaneous immunization, TCI). Here we investigated the role of regulatory T cells (Treg) and the suppressive cytokine IL-10 in restricting TCI-induced cytotoxic T lymphocyte (CTL) responses. Methodology/Principal Findings: TCI was performed with an ointment containing the TLR7 agonist imiquimod and a CTL epitope was applied to the depilated back skin of C57BL/6 mice. Using specific antibodies and FoxP3-diphteria toxin receptor transgenic (DEREG) mice, we interrogated inhibiting factors after…

2015

Characterization of host-pathogen interactions is a fundamental approach in microbiological and immunological oriented disciplines. It is commonly accepted that host cells start to change their phenotype after engulfing pathogens. Techniques such as real time PCR or ELISA were used to characterize the genes encoding proteins that are associated either with pathogen elimination or immune escape mechanisms. Most of such studies were performed in vitro using primary host cells or cell lines. Consequently, the data generated with such approaches reflect the global RNA expression or protein amount recovered from all cells in culture. This is justified when all host cells harbor an equal amount o…

Microbial Food Web Components as Potential Indicators of Urban Hydroecosystems / Mikrobiālās ķēdēs Komponentu Potenciāls Pielietojums Urbānās Vides Ū…

2015

Abstract Assessment of the effect of urbanisation on biodiversity and ecological impact studies are focused on plants, birds, terrestrial arthropods, and relatively few studies have been on aquatic organisms. The aim of this study was to investigate the microbial food web components as potential indicators of the trophic state of two small natural lakes (Gaiļezers, Bābelītis), two artificial lakes or reservoirs (created after excavation activities before 20 years) and the Gulf of Riga seaside Vecāķi beach (littoral), all of which are located in the city of Riga or close to it. Analysis of samples was conducted from April til October 2014 by epifluorescense microscopy for pico and nanoplankt…

Use of Flow Cytometry for Producing Tetraploids in Red Clover

2020

Abstract Sprouts of diploid red clover ‘Stendes Agrais’ were treated with 0.2% colchicine solution. The ploidy level of plants was detected by flow cytometry. Most of the treated plants were mixoploids and sterile. From progenies of fertile plants, mixoploids were selected that had a proportion of tetraploid cells higher than 60%. In the next generation, stable tetraploid plants were selected, and 49 lines were included in the breeding process.