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Abstract

Rickettsiae are able to spread within infected cell mono-layers by modifying intra-cellular actin formations. The study analyzes whether a visualization of actin modifications in addition to specific immuno-fluorescence staining of rickettsiae might facilitate the proof of rickettsial growth in cell culture.

Cell mono-layers of Vero E6 und BGM cells were infected with Rickettsia honei. Intra-cellular actin was fluorescence stained with TRITC-(tetra-methyl-5,6-isothiocyanate)-labeled phalloidin in addition to specific immuno-fluorescence staining of rickettsiae with FITC-(fluorescein-isothiocyanate)-labeled antibodies. DNA of bacteria and cells was counter-stained with DAPI (4′,6- diamino-2-phenyl-indole). Cell cultures infected with Vaccinia virus were used as positive controls, cell cultures infected with Coxiella burnetii as negative controls.

High concentrations of R. honei are necessary to demonstrate characteristic modifications of the intra-cellular actin. This effect is more pronounced in Vero E6 cells than in BGM cells.

Actin staining with phalloidin is not suited for an early proof of rickettsial growth in cell culture but may confirm unclear findings in specific immuno-fluorescence staining in case of sufficient bacterial density.

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. (2004) Toxicology investigations with cell culture systems: 20 years after. Toxicol. in Vitro 18 , 153–163. Stammati A. Toxicology investigations with cell culture systems: 20

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Effects of capsaicin on voltage-gated currents were examinedin vitro by whole-cell patch-clamp recordings from small neurones of rat trigeminal ganglia either in slice preparations or in different cell cultures. Cells were classified as sensitive to capsaicin if they responded with inward current and/or conductance change to the agent in nanomolar concentration. Capsaicin (150 to 330 nM) in sensitive cells reduced the mixed inward current evoked by depolarizing step or ramp commands in all preparations. In cultured cells, the inward current was depressed to 32.78±26.42% (n = 27) of the control. Both the tetrodotoxin-sensitive and -resistant inward currents were affected. The data support the concept that capsaicin besides acting on VR-1 receptors inhibits also some voltage gated channels. In 34 cultured cells, capsaicin increased the slope conductance to 170.5±68%. Percentage of capsaicin sensitive cells observed in nerve growth factor-treated cultured cell populations was higher (77.8%) than in the two other preparations (14.3 or 38.8%). It is concluded that 1) depression of the voltage-gated currents may play an important role in the functional desensitization of the sensory receptors and in the analgesic effect induced by the agent and 2) cell body of sensory neurones under native condition seems less sensitive to capsaicin then that of cells cultured in the presence of nerve growth factor.

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Acta Veterinaria Hungarica
Authors: Virág Somogyi, Tamás L. Horváth, István Tóth, Tibor Bartha, László Vilmos Frenyó, Dávid Sándor Kiss, Gergely Jócsák, Annamária Kerti, Frederick Naftolin and Attila Zsarnovszky

Thyroid hormones (THs) and oestrogens are crucial in the regulation of cerebellar development. TH receptors (TRs) mediate these hormone effects and are regulated by both hormone families. We reported earlier that THs and oestradiol (E2) determine TR levels in cerebellar cell culture. Here we demonstrate the effects of low concentrations (10–10 M) of the endocrine disruptor (ED) bisphenol A (BPA) on the hormonal (THs, E2) regulation of TRα,β in rat cerebellar cell culture. Primary cerebellar cell cultures, glia-containing and glia-destroyed, were treated with BPA or a combination of BPA and E2 and/or THs. Oestrogen receptor and TH receptor mRNA and protein levels were determined by real-time qPCR and Western blot techniques. The results show that BPA alone decreases, while BPA in combination with THs and/or E2 increases TR mRNA expression. In contrast, BPA alone increased receptor protein expressions, but did not further increase them in combination with THs and/or E2. The modulatory effects of BPA were mediated by the glia; however, the degree of changes also depended on the specific hormone ligand used. The results signify the importance of the regulatory mechanisms interposed between transcription and translation and raise the possibility that BPA could act to influence nuclear hormone receptor levels independently of ligand–receptor interaction.

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selection of expression system is based on its productivity with acceptable product quality attributes [ 14 ]. The cell culture processes for therapeutic protein production can follow three different types. The simplest mammalian cell culture process

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Acta Microbiologica et Immunologica Hungarica
Authors: Zahra Javanmard, Behrooz Sadeghi Kalani, Shabnam Razavi, Narges Nodeh Farahani, Rokhsareh Mohammadzadeh, Fatemeh Javanmard and Gholamreza Irajian

resistance, the aim of this study was to design antisense and intrusive peptide sequences to inhibit cag A virulence gene in the laboratory environment and cell culture in H. pylori bacteria. Materials and Methods

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Acta Microbiologica et Immunologica Hungarica
Authors: Zahra Javanmard, Behrooz Sadeghi Kalani, Shabnam Razavi, Narges Nodeh Farahani, Rokhsareh Mohammadzadeh, Fatemeh Javanmard and Gholamreza Irajian

resistance, the aim of this study was to design antisense and intrusive peptide sequences to inhibit cag A virulence gene in the laboratory environment and cell culture in H. pylori bacteria. Materials and Methods

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Gowri, G., Paiva, N. L. and Dixon, R. A. (1991): Stress responses in alfalfa ( Medicago sativa L.). 12. Sequence analysis of phenylalanine ammonia-lyase (PAL) cDNA clones and appearance of PAL transcripts in elicitor-treated cell cultures and developing

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. C., Kwon, M. S., Wie, M. B. (2003) Quercetin attenuates oxygen-glucose deprivation and excitotoxin-induced neurotoxicity in primary cortical cell cultures. Biol. Pharm. Bull. 26 , 544–546. Wie M. B

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The aim of this study was to investigate the effects on the immune response of levamisole alone and in conjunction with Candida albicans stimulation in human macrophage cell culture by determining the alterations in the levels of cytokine release.Levamisole treatment was performed before, during and after infecting U-937 human macrophage cells with C. albicans. In cell supernatants, interleukin (IL)-1b, IL-12, IL-18, tumour necrosis factor alpha (TNF-α) levels were measured by ELISA.In vitro levamisole treatment accompanied by C. albicans stimulation significantly increased IL-12, IL-1β and IL-18 production in macrophage cells (p < 0.05). It was observed that when administered before C. albicans infection, levamisole significantly increased IL-12 and IL-1β production in macrophage cells (p < 0.05). Another finding was that when applied to macrophage cells simultaneously with C. albicans infection, or before infection with C. albicans, levamisole suppressed the TNF-β production stimulating effect of C. albicans (p < 0.05).These results indicated that levamisole could be useful in treating patients infected with C. albicans or in protecting individuals under the risk of being infected with this pathogen. There is a need for further experimental and clinical studies on this hypothesis.

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