The widespread use of electricity raises the question of whether or not 50 Hz (power line frequency in Europe) magnetic fields (MFs) affect organisms. We investigated the transcription of Escherichia coli K-12 MG1655 in response to extremely low-frequency (ELF) MFs. Fields generated by three signal types (sinusoidal continuous, sinusoidal intermittent, and power line intermittent; all at 50 Hz, 1 mT), were applied and gene expression was monitored at the transcript level using an Affymetrix whole-genome microarray. Bacterial cells were grown continuously in a chemostat (dilution rate D = 0.4 h-1) fed with glucose-limited minimal medium and exposed to 50 Hz MFs with a homogenous flux density of 1 mT. For all three types of MFs investigated, neither bacterial growth (determined using optical density) nor culturable counts were affected. Likewise, no statistically significant change (fold-change > 2, P 0.01) in the expression of 4,358 genes and 714 intergenic regions represented on the gene chip was detected after MF exposure for 2.5 h (1.4 generations) or 15 h (8.7 generations). Moreover, short-term exposure (8 min) to the sinusoidal continuous and power line intermittent signal neither affected bacterial growth nor showed evidence for reliable changes in transcription. In conclusion, our experiments did not indicate that the different tested MFs (50 Hz, 1 mT) affected the transcription of E. coli.
Genome-wide transcription analysis of Escherichia coli in response to extremely low-frequency magnetic fields.
Treatment
View SamplesMesenchymal stromal cells (MSC) are multipotent cells that potentially promote angiogenesis. Especially MSC derived from the amnionic membrane of human term placentas (hAMSC) are promising candidates for a therapeutic use in vascular diseases, as cells can be isolated using non-invasive methods and are immunologically tolerated in vivo. In this study, we wanted to evaluate the endothelial differentiation potential of hAMSC.
Amnion-derived mesenchymal stromal cells show angiogenic properties but resist differentiation into mature endothelial cells.
Specimen part
View SamplesAnalysis of differential gene expression. The influence of a constitutively activated mutant Kit receptor on gene expression in fetal hematopoietic cells was analyzed. Results provide information of genes and cellular processes that are influenced by Kit signaling.
Kit transduced signals counteract erythroid maturation by MAPK-dependent modulation of erythropoietin signaling and apoptosis induction in mouse fetal liver.
Specimen part
View Samples- Background and Aims: Oxygen can fall to low concentrations within plant tissues, either because of environmental factors that decrease the external oxygen concentration or because the movement of oxygen through the plant tissues cannot keep pace with the rate of oxygen consumption. Recent studies document that plants can decrease their oxygen consumption in response to relative small changes in oxygen concentrations to avoid internal anoxia. The molecular mechanisms underlying this response have not been identified yet. The aim of this study was to use transcript and metabolite profiling to investigate the genomic response of Arabidopsis roots to a mild decrease in oxygen concentrations.
Transcript and metabolite profiling of the adaptive response to mild decreases in oxygen concentration in the roots of arabidopsis plants.
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View SamplesMesenchymal stromal cells (MSC) were isolated from human bone marrow. Here, we have compared gene expression profiles of MSC at early and late passages and upon stimulation with transforming growth factor beta 1 (TGF-b1). Stimulation was performed with 1ng/mL TGF-b1 for 1, 4, or 12 hours as indicated. The goal of this study was to determine if senescence-associated gene expression changes and TGF-b1 induced gene expression changes are related.
TGF-beta1 does not induce senescence of multipotent mesenchymal stromal cells and has similar effects in early and late passages.
Specimen part, Treatment, Subject
View SamplesMultipotent progenitors (MPP) and common dendritic cell progenitors (CDP) were obtained from mouse bone marrow, followed by in vitro culture with a specific cytokine cocktail and FACS sorting (Felker et al., 2010; Ser et al., 2012). Cells were treated with 10 ng/ml recombinant human TGF-1 (R&D Systems, Minneapolis, USA) for 2, 4, 8, 12 and 24 h as described (Felker et al., 2010) or left untreated.
TGF-β stimulation in human and murine cells reveals commonly affected biological processes and pathways at transcription level.
Specimen part
View SamplesWe here compared gene expression profiles in HepG2 cells upon stimulation with 1 ng/ml TGF-beta1 for 20 min, 1 hour, 2 hours, 4 hours, and 24 hours with untreated control cells. Experiments were done in three independent replicates. The goal of this study was to determine genes regulated by TGF-beta1.HepG2 cells were obtained from DSMZ (Braunschweig, Germany) and cell identity confirmed by STR profiling using the AmpFlSTR Identfiler Direct PCR Amplification kit (Life Technologies, Darmstadt, Germany). Gene expression profiles were compared at indicated time points after stimulation with TGF-beta (1 ng/ml) using the Human Gene 1.0 ST arrays (Affymetrix). In total 18 hybridizations are included in this series.
TGF-β stimulation in human and murine cells reveals commonly affected biological processes and pathways at transcription level.
Specimen part, Cell line, Time
View SamplesWe here compared gene expression profiles of primary murine hepatocytes (mPC) upon stimulation with 1 ng/ml TGF-beta1 for 20 min, 2 hours and 4 hours with untreated cells. Experiments were done in three independent replicates. The goal of this study was to determine genes regulated by TGF-beta1.
TGF-β stimulation in human and murine cells reveals commonly affected biological processes and pathways at transcription level.
Sex, Specimen part, Time
View SamplesPathogen-associated molecular patterns decisively influence antiviral immune responses, whereas the contribution of endogenous signals of tissue damage, also known as damage-associated molecular patterns or alarmins, remains ill-defined. We show that interleukin-33 (IL-33), an alarmin released from necrotic cells, is necessary for potent CD8+ T cell (CTL) responses to replicating, prototypic RNA and DNA viruses in mice. IL-33 signaled through its receptor on activated CTLs, enhanced clonal expansion in a MyD88-dependent, CTL-intrinsic fashion, determined polyfunctional effector cell differentiation and was necessary for virus control. Moreover, recombinant IL-33 augmented vaccine-induced CTL responses. Radio-resistant cells of the splenic T cell zone produced IL-33, and efficient CTL responses required IL-33 from radio-resistant cells but not from hematopoietic cells. Thus, alarmin release by radio-resistant cells orchestrates protective antiviral CTL responses.
The alarmin interleukin-33 drives protective antiviral CD8⁺ T cell responses.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
The alarmin IL-33 promotes regulatory T-cell function in the intestine.
Specimen part
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