Project description:The effects of cerium oxide nanoparticles on the gene expression of Gram-negative Escherichia coli is tested. 8 cultures of E. coli were treated with either cerium nanoparticles or cerium chloride solution at 50 mgs/ml. 4 cultures were untreated.
Project description:The study evaluates potential protective effects of cerium oxide nanoparticles (nanoceria) against oxidative stress in muscle tissue, both on ground and in space
Project description:Human Hepatocellular Carcinoma cells (HepG2) were exposed to six nanomaterials containing either Cerium oxide (CeO2) or Titanium oxide (TiO2) nanoparticles. Three different concentrations were tested: 0.3, 3, or 30 μg/mL) for 3 days. Microarray analysis was performed to identify genes differentially expressed following exposure to these chemicals.
Project description:We used a next-generation sequencing approach to understand the effects of antioxidant cerium oxide nanoparticles (CeO2) on neuronal stem cell differentiation. As a model we used the murine neuronal progenitor cell line, C17.2, which upon differentiation, is able to generate a mixed culture of neurons and neuroglial cells. As additional controls we used N-acetylcysteine (NAC), a conventional antioxidant and samarium doped cerium oxide nanoparticles (Sm-CeO2), as particle controls (as they bear a reduced antioxidant potential as compared to CeO2 alone). We had a time series approach and we investigates effects after 1, 4 and 7 days during differentiation. We revealed that CeO2 reduce axonal guidance signalling, neuronal differentiation and neuroglial differentiation after 7 days, thus having a negative effect on neuronal development. Overall, these effects are likely due to the antioxidant properties of nanoceria, although some evidence for a particle effect was also provided as indicated by the interference with cytoskeletal as well as integrin signaling genes both by nanoceria and Sm-doped nanoceria, but not by NAC.
Project description:To determine how transcriptome is altered by knockdown of NRF2, MLL1, or UTX, we performed RNA-sequencing (RNA-seq) analysis of HaCaT cells and its shRNA-expressing derivatives before and after exposure to hydrogen peroxide (H2O2) or cerium oxide nanoparticles (CeO2 NPs).
Project description:We have employed whole genome microarray expression to distinguish the effect of environmental aging on the toxicity of several cerium oxide nanoparticles (NPs) in human intestinal cells compared . Cells were exposed in vitro, and datasets of differentially expressed genes were identified for each type of NPs versus control samples.
Project description:Gram-negative bacteria possess stress responses to maintain the integrity of the cell envelope. Stress sensors monitor outer membrane permeability, envelope protein folding, and energization of the inner membrane. The systems used by Gram-negative bacteria to sense and combat stress resulting from disruption of the peptidoglycan layer are not well characterized. The peptidoglycan layer is a single molecule that completely surrounds the cell and ensures its structural integrity. During cell growth new peptidoglcyan subunits are incorporated into the peptidoglycan layer by a series of enzymes called the penicillin-binding proteins (PBPs). To explore how Gram-negative bacteria respond to peptidoglycan stress, global gene expression analysis was used to identify Escherichia coli stress responses activated following inhibition of specific PBPs by the β-lactam antibiotics mecillinam and cefsulodin. Inhibition of PBPs with different roles in peptidoglycan synthesis has different consequences for cell morphology and viability, suggesting that not all perturbations to the peptidoglycan layer generate equivalent stresses. We demonstrate that inhibition of different PBPs resulted in both shared and unique stress responses. The regulation of capsular synthesis (Rcs) phosphorelay was activated by inhibition of all of the PBPs tested. Furthermore, we show that activation of the Rcs phosphorelay increased survival in the presence of these antibiotics, independently of capsule synthesis. Both activation of the phosphorelay and survival required signal transduction via the outer membrane lipoprotein RcsF and the response regulator RcsB. We propose that the Rcs pathway responds to peptidoglycan damage and contributes to the intrinsic resistance of E. coli to β-lactam antibiotics. We used microarrays to identify changes in gene expression resulting from treatment of Escherichia coli with the β-lactam antibiotics cefsulodin, mecillinam, or the combination. This SuperSeries is composed of the following subset Series:; GSE10158: Expression of Escherichia coli treated with cefsulodin and mecillinam, alone and in combination; GSE10159: Expression of Escherichia coli treated with cefsulodin and mecillinam, alone at the minimum inhibitory concentration Experiment Overall Design: Refer to individual Series
Project description:We have employed whole genome microarray expression to distinguish the effect of environmental aging on the toxicity of several cerium oxide nanoparticles (NPs) in human intestinal cells compared . Cells were exposed in vitro, and datasets of differentially expressed genes were identified for each type of NPs versus control samples. NPs induced gene expression in Caco-2 cells was measured at 24 hours after exposure . Six independent experiments were performed using different NPs and controls for each experiment.
Project description:The toxicity of silver and zinc oxide nanoparticles is hypothesised to be mediated by dissolved metal ions and cerium dioxide nanoparticles (CeO2 NPs) are hypothesised to induce toxicity specifically by oxidative stress dependant on their surface redox state. To test these hypotheses, RNAseq was applied to characterise the molecular responses of cells to metal nanoparticle and metal ion exposures. The human epithelial lung carcinoma cell line A549 was exposed to different CeO2 NPs with different surface charges, micron-sized and nano-sized silver particles and silver ions, micron-sized and nano-sized zinc oxide particles and zinc ions, or control conditions, for 1 hour, 6 hours and 24 hours. Concentrations were the lower of either EC20 or 128 micrograms/mL. Transcriptional responses were characterised by RNAseq transcriptomics using an Illumina HiSeq2500 .