| 1. |
- Ali, Neserin, et al.
(författare)
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Analysis of nanoparticle-protein coronas formed in vitro between nanosized welding particles and nasal lavage proteins.
- 2016
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Ingår i: Nanotoxicology. - : Taylor & Francis. - 1743-5390 .- 1743-5404. ; 10:2, s. 226-234
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Tidskriftsartikel (refereegranskat)abstract
- Welding fumes include agglomerated particles built up of primary nanoparticles. Particles inhaled through the nose will to some extent be deposited in the protein-rich nasal mucosa, and a protein corona will be formed around the particles. The aim was to identify the protein corona formed between nasal lavage proteins and four types of particles with different parameters. Two of the particles were formed and collected during welding and two were manufactured iron oxides. When nasal lavage proteins were added to the particles, differences were observed in the sizes of the aggregates that were formed. Measurements showed that the amount of protein bound to particles correlated with the relative size increase of the aggregates, suggesting that the surface area was associated with the binding capacity. However, differences in aggregate sizes were detected when nasal proteins were added to UFWF and Fe2O3 particles (having similar agglomerated size) suggesting that yet parameters other than size determine the binding. Relative quantitative mass spectrometric and gel-based analyses showed differences in the protein content of the coronas. High-affinity proteins were further assessed for network interactions. Additional experiments showed that the inhibitory function of secretory leukocyte peptidase inhibitor, a highly abundant nasal protein, was influenced by particle binding suggesting that an understanding of protein function following particle binding is necessary to properly evaluate pathophysiological events. Our results underscore the importance of including particles collected from real working environments when studying the toxic effects of particles because these effects might be mediated by the protein corona.
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| 2. |
- Assenhöj, Maria, et al.
(författare)
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Protein interaction, monocyte toxicity and immunogenic properties of cerium oxide crystals with 5% or 14% gadolinium, cobalt oxide and iron oxide nanoparticles–an interdisciplinary approach
- 2021
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Ingår i: Nanotoxicology. - : Taylor and Francis Ltd.. - 1743-5390 .- 1743-5404. ; 15:8, s. 1035-1038
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Tidskriftsartikel (refereegranskat)abstract
- Metal oxide nanoparticles are widely used in both consumer products and medical applications, but the knowledge regarding exposure-related health effects is limited. However, it is challenging to investigate nanoparticle interaction processes with biological systems. The overall aim of this project was to improve the possibility to predict exposure-related health effects of metal oxide nanoparticles through interdisciplinary collaboration by combining workflows from the pharmaceutical industry, nanomaterial sciences, and occupational medicine. Specific aims were to investigate nanoparticle-protein interactions and possible adverse immune reactions. Four different metal oxide nanoparticles; CeOx nanocrystals with 5% or 14% Gd, Co3O4, and Fe2O3, were characterized by dynamic light scattering and high-resolution transmission electron microscopy. Nanoparticle-binding proteins were identified and screened for HLA-binding peptides in silico. Monocyte interaction with nanoparticle–protein complexes was assessed in vitro. Herein, for the first time, immunogenic properties of nanoparticle-binding proteins have been characterized. The present study indicates that especially Co3O4-protein complexes can induce both ‘danger signals’, verified by the production of inflammatory cytokines and simultaneously bind autologous proteins, which can be presented as immunogenic epitopes by MHC class II. The clinical relevance of these findings should be further evaluated to investigate the role of metal oxide nanoparticles in the development of autoimmune disease. The general workflow identified experimental difficulties, such as nanoparticle aggregate formation and a lack of protein-free buffers suitable for particle characterization, protein analyses, as well as for cell studies. This confirms the importance of future interdisciplinary collaborations. © 2021 The Author(s).
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| 3. |
- Bayat, Narges, et al.
(författare)
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The effects of engineered nanoparticles on the cellular structure and growth of Saccharomyces cerevisiae
- 2014
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Ingår i: Nanotoxicology. - : Informa UK Limited. - 1743-5390 .- 1743-5404. ; 8:4, s. 363-373
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Tidskriftsartikel (refereegranskat)abstract
- In order to study the effects of nanoparticles (NPs) with different physicochemical properties on cellular viability and structure, Saccharomyces cerevisiae were exposed to different concentrations of TiO2-NPs (1-3 nm), ZnO-NPs (<100 nm), CuO-NPs (<50 nm), their bulk forms, Ag-NPs (10 nm) and single-walled carbon nanotubes (SWCNTs). The GreenScreen assay was used to measure cyto- and genotoxicity, and transmission electron microscopy (TEM) used to assess ultrastructure. Cu-ONPs were highly cytotoxic, reducing the cell density by 80% at 9 cm(2)/ml, and inducing lipid droplet formation. Cells exposed to Ag-NPs (19 cm(2)/ml) and TiO2-NPs (147 cm(2)/ml) contained dark deposits in intracellular vacuoles, the cell wall and vesicles, and reduced cell density (40 and 30%, respectively). ZnO-NPs (8 cm(2)/ml) caused an increase in the size of intracellular vacuoles, despite not being cytotoxic. SWCNTs did not cause cytotoxicity or significant alterations in ultrastructure, despite high oxidative potential. Two genotoxicity assays, GreenScreen and the comet assay, produced different results and the authors discuss the reasons for this discrepancy. Classical assays of toxicity may not be the most suitable for studying the effects of NPs in cellular systems, and the simultaneous assessment of other measures of the state of cells, such as TEM are highly recommended.
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| 4. |
- Bundschuh, Mirco
(författare)
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Nanosized titanium dioxide elevates toxicity of cationic metals species for Daphnia - have aging and natural organic matter an unexpected impact?
- 2022
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Ingår i: Nanotoxicology. - : Informa UK Limited. - 1743-5390 .- 1743-5404. ; 16, s. 16-28
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Tidskriftsartikel (refereegranskat)abstract
- In aquatic ecosystems, nanosized titanium dioxide particles (nTiO(2)) likely interact with natural organic matter (NOM) and may alter the ecotoxicity of co-occurring metals. The magnitude of changes in toxicity may be modulated by the duration of interactions (i.e. aging) between these factors. As those interactions are hardly addressed in literature, the present study aimed at assessing the impact of aging durations (0, 1, 3 and 6 days) on metals with mainly cationic (silver (Ag), cadmium (Cd)) or anionic (arsenic (As)) toxic ions in combination with three nTiO(2) levels (0.0, 0.6 and 3.0 mg/L) and two NOM levels (0 versus 8 mg TOC/L). The interaction of these factors was additionally investigated for two aging scenarios: in one scenario nTiO(2) were aged together with one of the metals, while in other scenario metals were added to aged nTiO(2). Subsequently, their combined acute effects on Daphnia magna were assessed. The results uncovered that nTiO(2) elevate the toxicity of metals with mainly cationic species (i.e. Ag+ and Cd2+) with the effect size depending on their valence electron. Contrary, nTiO(2) have no impact on the metal with mainly anionic species (i.e. HAsO42-). Furthermore, NOM reduced metal toxicity only for Ag and aging duration had a limited impact on the test outcome suggesting that relevant interactions between metal and nTiO(2) occur rather quick (below 24 h). These findings suggest that the charge of metals' most toxic species is the determining factor for its interaction with nanoparticles and the resulting ecotoxicological effect assessment.
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| 5. |
- Bundschuh, Mirco
(författare)
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Quantity and quality of natural organic matter influence the ecotoxicity of titanium dioxide nanoparticles
- 2016
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Ingår i: Nanotoxicology. - : Informa UK Limited. - 1743-5390 .- 1743-5404. ; 10, s. 1415-1421
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Tidskriftsartikel (refereegranskat)abstract
- Nanoparticles' fate is amongst other parameters determined by the quantity and quality of natural organic matter (NOM). Consequently, the ecotoxicity of nanoparticles is modified, while only little information is available on the NOM characteristics triggering this interplay. This study systematically examined how NOM quantity and quality influences the acute ecotoxicity of titanium dioxide nanoparticles (nTiO(2)) towards Daphnia magna. Therefore, two nTiO(2) products (A-100 and P25; approximate to 100nm) were investigated in combination with seven NOM types of variable quality at four levels each (up to 4.00mg total organic carbon/L). The results showed that - independent of the applied nTiO(2) product and NOM type - nTiO(2) ecotoxicity decreased up to a factor of>18 with increasing NOM concentration. More importantly, increasing levels of aromaticity and hydrophobicity of the NOM decreased the magnitude of toxic effects caused by nTiO(2), which was again independent of the nTiO(2) product tested. In the light of the ubiquitary presence of NOM, the ecotoxicological risk of nTiO(2) in surface waters with high NOM loads is likely moderate. However, interactions of nTiO(2) and NOM in combination with other natural or chemical stressors are not well-understood but seem to be fundamental for a reliable risk assessment of nanoparticles.
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| 6. |
- Cappellini, Francesca, et al.
(författare)
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Mechanistic insight into reactivity and (geno)toxicity of well-characterized nanoparticles of cobalt metal and oxides
- 2018
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Ingår i: Nanotoxicology. - : Taylor & Francis. - 1743-5390 .- 1743-5404. ; 12:6, s. 602-620
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Tidskriftsartikel (refereegranskat)abstract
- An increasing use of cobalt (Co)-based nanoparticles (NPs) in different applications and exposures at occupational settings triggers the need for toxicity assessment. Improved understanding regarding the physiochemical characteristics of Co metal NPs and different oxides in combination with assessment of toxicity and mechanisms may facilitate decisions for grouping during risk assessment. The aim of this study was to gain mechanistic insights in the correlation between NP reactivity and toxicity of three different Co-based NPs (Co, CoO, and Co3O4) by using various tools for characterization, traditional toxicity assays, as well as six reporter cell lines (ToxTracker) for rapid detection of signaling pathways of relevance for carcinogenicity. The results showed cellular uptake of all NPs in lung cells and induction of DNA strand breaks and oxidative damage (comet assay) by Co and CoO NPs. In-depth studies on the ROS generation showed high reactivity of Co, lower for CoO, and no reactivity of Co3O4 NPs. The reactivity depended on the corrosion and transformation/dissolution properties of the particles and the media highlighting the role of the surface oxide and metal speciation as also confirmed by in silico modeling. By using ToxTracker, Co NPs were shown to be highly cytotoxic and induced reporters related to oxidative stress (Nrf2 signaling) and DNA strand breaks. Similar effects were observed for CoO NPs but at higher concentrations, whereas the Co3O4 NPs were inactive at all concentrations tested. In conclusion, our study suggests that Co and CoO NPs, but not Co3O4, may be grouped together for risk assessment.
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| 7. |
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| 8. |
- Cronholm, Pontus, et al.
(författare)
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Effect of sonication and serum proteins on copper release from copper nanoparticles and the toxicity towards lung epithelial cells
- 2011
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Ingår i: Nanotoxicology. - : Informa UK Limited. - 1743-5390 .- 1743-5404. ; 5:2, s. 269-281
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Tidskriftsartikel (refereegranskat)abstract
- Different methodological settings can influence particle characteristics and toxicity in nanotoxicology. The aim of this study was to investigate how serum proteins and sonication of Cu nanoparticle suspensions influence the properties of the nanoparticles and toxicological responses on human lung epithelial cells. This was investigated by using methods for particle characterization (photon correlation spectroscopy and TEM) and Cu release (atomic absorption spectroscopy) in combination with assays for analyzing cell toxicity (MTT-, trypan blue- and Comet assay). The results showed that sonication of Cu nanoparticles caused decreased cell viability and increased Cu release compared to non-sonicated particles. Furthermore, serum in the cell medium resulted in less particle agglomeration and increased Cu release compared with medium without serum, but no clear difference in toxicity was detected. Few cells showed intracellular Cu nanoparticles due to fast release/dissolution processes of Cu. In conclusion; sonication can affect the toxicity of nanoparticles.
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| 9. |
- Ekstrand-Hammarström, Barbro, et al.
(författare)
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Human Primary Bronchial Epithelial Cells are more Responsive to Titanium Dioxide Nanoparticles than the Lung Epithelial Cell Lines A549 and BEAS-2B
- 2012
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Ingår i: Nanotoxicology. - : Informa Healthcare. - 1743-5390 .- 1743-5404. ; 6:6, s. 623-634
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Tidskriftsartikel (refereegranskat)abstract
- We have compared the cellular uptake and responses of fivepreparations of nanocrystalline titanium dioxide (TiO2) betweennormal human bronchial epithelial (NHBE) cells and epithelialcell lines (A549 and BEAS-2B). The P25 nanoparticles, containingboth anatase and rutile modifications, induced reactive oxygenspecies (ROS) and secretion of the neutrophil chemoattractantIL-8 in all three cell types used. Pure anatase and rutile particlesprovoked differential IL-8 response in A549 and no response inBEAS-2B cells despite similar formation of ROS. The pure TiO2modifications also provoked release of the inflammatorymediators: IL-6, G-CSF and VEGF, in NHBE cells but not in the twocell lines. We conclude that the responsiveness of lung epithelialcells is strongly dependent on both the physicochemicalproperties of TiO2 nanoparticles and the type of responder cells.The differential pro-inflammatory responsiveness of primarylung epithelial cells compared with immortalized cell linesshould be considered in the assessment of adverse reactions toinhaled nanoparticles.
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| 10. |
- Ekstrand-Hammarström, Barbro, et al.
(författare)
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Human primary bronchial epithelial cells respond differently to titanium dioxide nanoparticles than the lung epithelial cell lines A549 and BEAS-2B
- 2012
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Ingår i: Nanotoxicology. - : Informa UK Limited. - 1743-5390 .- 1743-5404. ; 6:6, s. 623-634
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Tidskriftsartikel (refereegranskat)abstract
- We have compared the cellular uptake and responses of five preparations of nanocrystalline titanium dioxide (TiO(2)) between normal human bronchial epithelial (NHBE) cells and epithelial cell lines (A549 and BEAS-2B). The P25 nanoparticles, containing both anatase and rutile modifications, induced reactive oxygen species (ROS) and secretion of the neutrophil chemoattractant IL-8 in all three cell types used. Pure anatase and rutile particles provoked differential IL-8 response in A549 and no response in BEAS-2B cells despite similar formation of ROS. The pure TiO(2) modifications also provoked release of the inflammatory mediators: IL-6, G-CSF and VEGF, in NHBE cells but not in the two cell lines. We conclude that the responsiveness of lung epithelial cells is strongly dependent on both the physicochemical properties of TiO(2) nanoparticles and the type of responder cells. The differential pro-inflammatory responsiveness of primary lung epithelial cells compared with immortalized cell lines should be considered in the assessment of adverse reactions to inhaled nanoparticles.
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| 11. |
- Ekvall, Mikael T., et al.
(författare)
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Long-term effects of tungsten carbide (WC) nanoparticles in pelagic and benthic aquatic ecosystems
- 2018
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Ingår i: Nanotoxicology. - : Taylor & Francis. - 1743-5390 .- 1743-5404. ; 12:1, s. 79-89
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Tidskriftsartikel (refereegranskat)abstract
- As the production and usage of nanomaterials are increasing so are the concerns related to the release of the material into nature. Tungsten carbide (WC) is widely used for its hard metal properties, although its use, in for instance tyre studs, may result in nano-sized particles ending up in nature. Here, we evaluate the potential long-term exposure effects of WC nanoparticles on a pelagic (Daphnia magna) and a benthic (Asellus aquaticus) organism. No long-term effects were observed in the benthic system with respect to population dynamics or ecosystem services. However, long-term exposure of D. magna resulted in increased time to first reproduction and, if the particles were resuspended, strong effects on survival and reproductive output. Hence, the considerable differences in acute vs. long-term exposure studies revealed here emphasize the need for more long-term studies if we are to understand the effects of nanoparticles in natural systems.
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| 12. |
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| 13. |
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| 14. |
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| 15. |
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| 16. |
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| 17. |
- Kelpsiene, Egle, et al.
(författare)
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The effect of natural biomolecules on yttrium oxide nanoparticles from a Daphnia magna survival rate perspective
- 2023
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Ingår i: Nanotoxicology. - : Taylor and Francis Ltd.. - 1743-5390 .- 1743-5404. ; 17:4, s. 385-399
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Tidskriftsartikel (refereegranskat)abstract
- The attention to rare earth oxide nanoparticles (NPs), including yttrium oxide (Y2O3), has increased in many fields due to their unique structural characteristics and functional properties. The aim of our study was to investigate the mechanisms by which bio-corona formation on Y2O3 NPs affects their environmental fate and toxicity. The Y2O3 NPs induced toxicity to freshwater filter feeder Daphnia magna at particle concentrations of 1 and 10 mg/L, regardless of particle size. Interactions between naturally excreted biomolecules (e.g. protein, lipids, and polysaccharides) derived from D. magna, and the Y2O3 NPs (30–45 nm) resulted in the formation of an eco-corona, which reduced their toxic effects toward D. magna at a particle concentration of 10 mg/L. No effects were observed at lower concentrations or for the other particle sizes investigated. Copper-zinc (Cu-Zn) superoxide dismutase, apolipophorins, and vitellogenin-1 proteins proved to be the most prominent proteins of the adsorbed corona, and possibly a reason for the reduced toxicity of the 30–45 nm Y2O3 NPs toward D. magna.
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| 18. |
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| 19. |
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| 20. |
- Liu, Wei, et al.
(författare)
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Impact of silver nanoparticles on human cells : effect of particle size
- 2010
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Ingår i: Nanotoxicology. - New York : Informa Healthcare. - 1743-5390 .- 1743-5404. ; 4:3, s. 319-330
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Tidskriftsartikel (refereegranskat)abstract
- This work investigated the cytotoxicities of three silver nanoparticles (SNPs) SNP-5, SNP-20 and SNP-50 with different sizes ( approximately 5 nm, approximately 20 nm and approximately 50 nm) using four human cell models (A549, SGC-7901, HepG2 and MCF-7). Endpoints included cell morphology, cell viability, cellular membrane integrity, oxidative stress and cell cycle progression. Observable deleterious effects on the cell morphologies and membrane integrity were induced by SNP-5 and SNP-20. SNPs elevated the ROS levels in cells and arrested the cells at S phase. Apoptosis occurred for 4-9% of the exposed cells. All these cellular responses as well as EC50 values were found to be size-dependent for the tested SNPs. Ultrastructural observations confirmed the presence of SNPs inside cells. Elemental analysis of silver in cells by ICP-MS showed that smaller nanoparticles enter cells more easily than larger ones, which may be the cause of higher toxic effects. The findings may assist in the design of SNP applications and provide insights into their toxicity.
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| 21. |
- Lovén, Karin, et al.
(författare)
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Toxicological effects of zinc oxide nanoparticle exposure : an in vitro comparison between dry aerosol air-liquid interface and submerged exposure systems
- 2021
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Ingår i: Nanotoxicology. - : Taylor and Francis Ltd.. - 1743-5390 .- 1743-5404. ; 15:4, s. 494-510
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Tidskriftsartikel (refereegranskat)abstract
- Engineered nanomaterials (ENMs) are increasingly produced and used today, but health risks due to their occupational airborne exposure are incompletely understood. Traditionally, nanoparticle (NP) toxicity is tested by introducing NPs to cells through suspension in the growth media, but this does not mimic respiratory exposures. Different methods to introduce aerosolized NPs to cells cultured at the air-liquid-interface (ALI) have been developed, but require specialized equipment and are associated with higher cost and time. Therefore, it is important to determine whether aerosolized setups induce different cellular responses to NPs than traditional ones, which could provide new insights into toxicological responses of NP exposure. This study evaluates the response of human alveolar epithelial cells (A549) to zinc oxide (ZnO) NPs after dry aerosol exposure in the Nano Aerosol Chamber for In Vitro Toxicity (NACIVT) system as compared to conventional, suspension-based exposure: cells at ALI or submerged. Similar to other studies using nebulization of ZnO NPs, we found that dry aerosol exposure of ZnO NPs via the NACIVT system induced different cellular responses as compared to conventional methods. ZnO NPs delivered at 1.0 µg/cm2 in the NACIVT system, mimicking occupational exposure, induced significant increases in metabolic activity and release of the cytokines IL-8 and MCP-1, but no differences were observed using traditional exposures. While factors associated with the method of exposure, such as differing NP aggregation, may contribute toward the different cellular responses observed, our results further encourage the use of more physiologically realistic exposure systems for evaluating airborne ENM toxicity. © 2021 The Author(s).
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| 22. |
- Mattsson, Karin, et al.
(författare)
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Disaggregation of gold nanoparticles by Daphnia magna
- 2018
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Ingår i: Nanotoxicology. - : Informa UK Limited. - 1743-5390 .- 1743-5404. ; 12:8, s. 885-900
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Tidskriftsartikel (refereegranskat)abstract
- The use of manufactured nanomaterials is rapidly increasing, while our understanding of the consequences of releasing these materials into the environment is still limited and many questions remain, for example, how do nanoparticles affect living organisms in the wild? How do organisms adapt and protect themselves from exposure to foreign materials? How does the environment affect the performance of nanoparticles, including their surface properties? In an effort to address these crucial questions, our main aim has been to probe the effects of aquatic organisms on nanoparticle aggregation. We have, therefore, carried out a systematic study with the purpose to disentangle the effects of the freshwater zooplankter, Daphnia magna, on the surface properties, stability, and aggregation properties of gold (Au) nanoparticles under different aqueous conditions as well as identified the proteins bound to the nanoparticle surface. We show that Au nanoparticles aggregate in pure tap water, but to a lesser extent in water that either contains Daphnia or has been pre-conditioned with Daphnia. Moreover, we show that proteins generated by Daphnia bind to the Au nanoparticles and create a modified surface that renders them less prone to aggregation. We conclude that the surrounding milieu, as well as the surface properties of the original Au particles, are important factors in determining how the nanoparticles are affected by biological metabolism. In a broader context, our results show how nanoparticles released into a natural ecosystem become chemically and physically altered through the dynamic interactions between particles and organisms, either through biological metabolism or through the interactions with biomolecules excreted by organisms into the environment.
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| 23. |
- Mattsson, Karin, et al.
(författare)
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Translocation of 40 nm diameter nanowires through the intestinal epithelium of Daphnia magna
- 2016
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Ingår i: Nanotoxicology. - : Informa UK Limited. - 1743-5390 .- 1743-5404. ; 10:8, s. 1160-1167
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Tidskriftsartikel (refereegranskat)abstract
- Nanowires (NWs) have unique electrical and optical properties of value for many applications including lighting, sensing, and energy harnessing. Consumer products containing NWs increase the risk of NWs being released in the environment, especially into aquatic ecosystems through sewage systems. Daphnia magna is a common, cosmopolitan freshwater organism sensitive to toxicity tests and represents a likely entry point for nanoparticles into food webs of aquatic ecosystems. Here we have evaluated the effect of NW diameter on the gut penetrance of NWs in Daphnia magna. The animals were exposed to NWs of two diameters (40 and 80 nm) and similar length (3.6 and 3.8 μm, respectively) suspended in water. In order to locate the NWs in Daphnia, the NWs were designed to comprise one inherently fluorescent segment of gallium indium phosphide (GaInP) flanked by a gallium phosphide (GaP) segment. Daphnia mortality was assessed directly after 24 h of exposure and 7 days after exposure. Translocation of NWs across the intestinal epithelium was investigated using confocal fluorescence microscopy directly after 24 h of exposure and was observed in 89% of Daphnia exposed to 40 nm NWs and in 11% of Daphnia exposed to 80 nm NWs. A high degree of fragmentation was observed for NWs of both diameters after ingestion by the Daphnia, although 40 nm NWs were fragmented to a greater extent, which could possibly facilitate translocation across the intestinal epithelium. Our results show that the feeding behavior of animals may enhance the ability of NWs to penetrate biological barriers and that penetrance is governed by the NW diameter.
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| 24. |
- McCarrick, Sarah, et al.
(författare)
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High variability in toxicity of welding fume nanoparticles from stainless steel in lung cells and reporter cell lines : the role of particle reactivity and solubility
- 2019
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Ingår i: Nanotoxicology. - : TAYLOR & FRANCIS LTD. - 1743-5390 .- 1743-5404.
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Tidskriftsartikel (refereegranskat)abstract
- Millions of people in the world perform welding as their primary occupation resulting in exposure to metal-containing nanoparticles in the fumes generated. Even though health effects including airway diseases are well-known, there is currently a lack of studies investigating how different welding set-ups and conditions affect the toxicity of generated nanoparticles of the welding fume. The aim of this study was to investigate the toxicity of nine types of welding fume particles generated via active gas shielded metal arc welding (GMAW) of chromium-containing stainless steel under different conditions and, furthermore, to correlate the toxicity to the particle characteristics. Toxicological endpoints investigated were generation of reactive oxygen species (ROS), cytotoxicity, genotoxicity and activation of ToxTracker reporter cell lines. The results clearly underline that the choice of filler material has a large influence on the toxic potential. Fume particles generated by welding with the tested flux-cored wire (FCW) were found to be more cytotoxic compared to particles generated by welding with solid wire or metal-cored wire (MCW). FCW fume particles were also the most potent in causing ROS and DNA damage and they furthermore activated reporters related to DNA double- strand breaks and p53 signaling. Interestingly, the FCW fume particles were the most soluble in PBS, releasing more chromium in the hexavalent form and manganese compared to the other fumes. These results emphasize the importance of solubility of different metal constituents of the fume particles, rather than the total metal content, for their acute toxic potential.
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| 25. |
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| 26. |
- Messing, Maria, et al.
(författare)
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Gas-borne particles with tunable and highly controlled characteristics.
- 2013
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Ingår i: Nanotoxicology. - : Informa UK Limited. - 1743-5404 .- 1743-5390. ; 7:6, s. 1052-1063
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Tidskriftsartikel (refereegranskat)abstract
- Abstract For nanotoxicology investigations of air-borne particles to provide relevant results it is ever so important that the particle exposure of, for example cells, closely resembles the "real" exposure situation, that the dosimetry is well defined, and that the characteristics of the deposited nanoparticles are known in detail. By synthesizing the particles in the gas-phase and directly depositing them on lung cells the particle deposition conditions in the lung is closely mimicked. In this work we present a setup for generation of gas-borne nanoparticles of a variety of different materials with highly controlled and tunable particle characteristics, and demonstrate the method by generation of gold particles. Particle size, number concentration and mass of individual particles of the population are measured on-line by means of differential mobility analyzers (DMA) and an aerosol particle mass analyzer (APM) whereas primary particle size and internal structure are investigated by transmission electron microscopy. A method for 3 estimating the surface area dose from the DMA-APM measurements is applied and we further demonstrate that for the setup used, a deposition time of around 1 hour is needed for deposition onto cells in an air liquid interface chamber, using electrostatic deposition, to reach a toxicological relevant surface area dose.
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| 27. |
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| 28. |
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| 29. |
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| 30. |
- Ogonowski, Martin, et al.
(författare)
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Multi-level toxicity assessment of engineered cellulose nanofibrils in Daphnia magna
- 2018
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Ingår i: Nanotoxicology. - : Taylor & Francis. - 1743-5390 .- 1743-5404. ; 12:6, s. 509-521
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Tidskriftsartikel (refereegranskat)abstract
- Cellulose nanofibril (CNF)-based materials are increasingly used in industrial and commercial applications. However, the impacts of CNF on aquatic life are poorly understood, and there are concerns regarding their potential toxicity. Using a combination of standard ecotoxicological tests and feeding experiments, we assessed the effects of CNF exposure (0.206-20.6 mg/L) on the feeding (food uptake and gut residence time) and life-history traits (growth and reproduction) in the cladoceran Daphnia magna. No mortality was observed in a 48 h acute exposure at 2060 mg/L. Moreover, a 21-day exposure at low food and moderate CNF levels induced a stimulatory effect on growth, likely driven by increased filtration efficiency, and, possibly, partial assimilation of the CNF by the animals. However, at low food levels and the highest CNF concentrations, growth and reproduction were negatively affected. These responses were linked to caloric restriction caused by dilution of the food source, but not an obstruction of the alimentary canal. Finally, no apparent translocation of CNF past the alimentary canal was detected. We conclude that CNF displays a low toxic potential to filter-feeding organisms and the expected environmental risks are low.
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| 31. |
- Park, Margriet V. D. Z., et al.
(författare)
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Development of a systematic method to assess similarity between nanomaterials for human hazard evaluation purposes - lessons learnt
- 2018
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Ingår i: Nanotoxicology. - : TAYLOR & FRANCIS LTD. - 1743-5390 .- 1743-5404. ; 12:7, s. 652-676
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Tidskriftsartikel (refereegranskat)abstract
- Within the EU FP-7 GUIDEnano project, a methodology was developed to systematically quantify the similarity between a nanomaterial (NM) that has been tested in toxicity studies and the NM for which risk needs to be evaluated, for the purpose of extrapolating toxicity data between the two materials. The methodology is a first attempt to use current knowledge on NM property-hazard relationships to develop a series of pragmatic and systematic rules for assessing NM similarity. Moreover, the methodology takes into account the practical feasibility, in that it is based on generally available NM characterization information. In addition to presenting this methodology, the lessons learnt and the challenges faced during its development are reported here. We conclude that there is a large gap between the information that is ideally needed and its application to real cases. The current database on property-hazard relationships is still very limited, which hinders the agreement on the key NM properties constituting the basis of the similarity assessment and the development of associated science-based and unequivocal rules. Currently, one of the most challenging NM properties to systematically assess in terms of similarity between two NMs is surface coating and functionalization, which lacks standardized parameters for description and characterization methodology. Standardization of characterization methods that lead to quantitative, unambiguous, and measurable parameters describing NM properties are necessary in order to build a sufficiently robust property-hazard database that allows for evidence-based refinement of our methodology, or any other attempt to systematically assess the similarity of NMs.
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| 32. |
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| 33. |
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| 34. |
- Rajapakse, K., et al.
(författare)
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Proteomic analyses of early response of unicellular eukaryotic microorganism Tetrahymena thermophila exposed to TiO2 particles.
- 2016
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Ingår i: Nanotoxicology. - Taylor & Francis : Informa UK Limited. - 1743-5390 .- 1743-5404. ; 10:5, s. 542-556
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Tidskriftsartikel (refereegranskat)abstract
- Key biological functions involved in cell survival have been studied to understand the difference between the impact of exposure to TiO2 nanoparticles (TiO2-NPs) and their bulk counterparts (bulk-TiO2). By selecting a unicellular eukaryotic model organism and applying proteomic analysis an overview of the possible impact of exposure could be obtained. In this study, we investigated the early response of unicellular eukaryotic protozoan Tetrahymena thermophila exposed to TiO2-NPs or bulk-TiO2 particles at subtoxic concentrations for this organism. The proteomic analysis based on 2DE + nLC-ESI-MS/MS revealed 930 distinct protein spots, among which 77 were differentially expressed and 18 were unambiguously identified. We identified alterations in metabolic pathways, including lipid and fatty acid metabolism, purine metabolism and energetic metabolism, as well as salt stress and protein degradation. This proteomic study is consistent with our previous findings, where the early response of T. thermophila to subtoxic concentrations of TiO2 particles included alterations in lipid and fatty acid metabolism and ion regulation. The response to the lowest TiO2-NPs concentration differed significantly from the response to higher TiO2-NPs concentration and both bulk-TiO2concentrations. Alterations on the physiological landscape were significant after exposure to both nano- and bulk-TiO2; however, no toxic effects were evidenced even at very high exposure concentrations. This study confirms the relevance of the alteration of the lipid profile and lipid metabolism in understanding the early impact of TiO2-NPs in eukaryotic cells, for example, phagocytosing cells like macrophages and ciliated cells in the respiratory epithelium.
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| 35. |
- Ribeiro, F., et al.
(författare)
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Uptake and elimination kinetics of silver nanoparticles and silver nitrate by Raphidocelis subcapitata: The influence of silver behaviour in solution
- 2015
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Ingår i: Nanotoxicology. - : Informa UK Limited. - 1743-5390 .- 1743-5404. ; 9:6, s. 686-695
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Tidskriftsartikel (refereegranskat)abstract
- Raphidocelis subcapitata is a freshwater algae species that constitutes the basis of many aquatic trophic chains. In this study, R. subcapitata was used as a model species to investigate the kinetics of uptake and elimination of silver nanoparticles (AgNP) in comparison to silver nitrate (AgNO3) with particular focus on the Ag sized-fractions in solution. AgNP used in this study were provided in a suspension of 1mg Ag/l, with an initial size of 3-8nm and coated with an alkane material. Algae was exposed for 48 h to both AgNP and AgNO3 and sampled at different time points to determine their internal Ag concentration over time. Samples were collected and separated into different sized fractions: total (Ag-tot), water column Ag (Ag-water), small particulate Ag (Ag-small.part.) and dissolved Ag (Ag-dis). At AgNO3 exposures algae reached higher bioconcentration factor (BCF) and lower elimination rate constants than at AgNP exposures, meaning that Ag is more readily taken up by algae in its dissolved form than in its small particulate form, however slowly eliminated. When modelling the kinetics based on the Ag-dis fraction, a higher BCF was found. This supports our hypothesis that Ag would be internalised by algae only in its dissolved form. In addition, algae images obtained by Coherent Anti-stokes Raman Scattering (CARS) microscopy demonstrated large aggregates of nanoparticles external to the algae cells with no evidence of its internalisation, thus providing a strong suggestion that these AgNP were not able to penetrate the cells and Ag accumulation happens through the uptake of Ag ions.
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| 36. |
- Skjolding, L. M., et al.
(författare)
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An assessment of the importance of exposure routes to the uptake and internal localisation of fluorescent nanoparticles in zebrafish (Danio rerio), using light sheet microscopy
- 2017
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Ingår i: Nanotoxicology. - : Informa UK Limited. - 1743-5390 .- 1743-5404. ; 11, s. 351-359
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Tidskriftsartikel (refereegranskat)abstract
- © 2017 Informa UK Limited, trading as Taylor & Francis Group.A major challenge in nanoecotoxicology is finding suitable methods to determine the uptake and localisation of nanoparticles on a whole-organism level. Some uptake methods have been associated with artefacts induced by sample preparation, including staining for electron microscopy. This study used light sheet microscopy (LSM) to define the uptake and localisation of fluorescently labelled nanoparticles in living organisms with minimal sample preparation. Zebrafish (Danio rerio) were exposed to fluorescent gold nanoparticles (Au NPs) and fluorescent polystyrene NPs via aqueous or dietary exposure. The in vivo uptake and localisation of NPs were investigated using LSM at different time points (1, 3 and 7 days). A time-dependent increase in fluorescence was observed in the gut after dietary exposure to both Au NPs and polystyrene NPs. No fluorescence was observed within gut epithelia regardless of the NP exposure route indicating no or limited uptake via intestinal villi. Fish exposed to polystyrene NPs through the aqueous phase emitted fluorescence signals from the gills and intestine. Fluorescence was also detected in the head region of the fish after aqueous exposure to polystyrene NPs. This was not observed for Au NPs. Aqueous exposure to Au NPs resulted in increased relative swimming distance, while no effect was observed for other exposures. This study supports that the route of exposure is essential for the uptake and subsequent localisation of nanoparticles in zebrafish. Furthermore, it demonstrates that the localisation of NPs in whole living organisms can be visualised in real-time, using LSM.
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| 37. |
- Åkerlund, Emma, et al.
(författare)
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Inflammation and (secondary) genotoxicity of Ni and NiO nanoparticles
- 2019
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Ingår i: Nanotoxicology. - : Taylor & Francis. - 1743-5390 .- 1743-5404. ; 13:8, s. 1060-1072
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Tidskriftsartikel (refereegranskat)abstract
- Nanoparticle-induced genotoxicity can arise through different mechanisms, and generally, primary and secondary genotoxicity can be distinguished where the secondary is driven by an inflammatory response. It is, however, yet unclear how a secondary genotoxicity can be detected using in vitro methods. The aim of this study was to investigate inflammation and genotoxicity caused by agglomerated nickel (Ni) and nickel oxide (NiO) nanoparticles and, furthermore, to explore the possibility to test secondary (inflammation-driven) genotoxicity in vitro. As a benchmark particle to compare with, we used crystalline silica (quartz). A proteome profiler antibody array was used to screen for changes in release of 105 different cytokines and the results showed an increased secretion of various cytokines including vascular endothelial growth factor (VEGF) following exposure of macrophages (differentiated THP-1 cells). Both Ni and NiO caused DNA damage (comet assay) following exposure of human bronchial epithelial cells (HBEC) and interestingly conditioned media (CM) from exposed macrophages also resulted in DNA damage (2- and 3-fold increase for Ni and NiO, respectively). Similar results were also found when using a co-culture system of macrophages and epithelial cells. In conclusion, this study shows that it is possible to detect a secondary genotoxicity in lung epithelial cells by using in vitro methods based on conditioned media or co-cultures. Further investigation is needed in order to find out what factors that are causing this secondary genotoxicity and whether such effects are caused by numerous nanoparticles.
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| 38. |
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