Potential Impact of Low-Concentration Silver Nanoparticles on Predator–Prey Interactions between Predatory Dragonfly Nymphs and Daphnia magna as a Prey

2012 ◽  
Vol 46 (14) ◽  
pp. 7755-7762 ◽  
Author(s):  
Lok R. Pokhrel ◽  
Brajesh Dubey
Keyword(s):  
Silver Nanoparticles ◽  
Daphnia Magna ◽  
Predator Prey ◽  
Low Concentration ◽  
Potential Impact ◽  
Dragonfly Nymphs

Silver nanoparticles and silver nitrate induce high toxicity to Pseudokirchneriella subcapitata, Daphnia magna and Danio rerio

2014 ◽  
Vol 466-467 ◽  
pp. 232-241 ◽  
Author(s):  
Fabianne Ribeiro ◽  
Julián Alberto Gallego-Urrea ◽  
Kerstin Jurkschat ◽  
Alison Crossley ◽  
Martin Hassellöv ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Silver Nitrate ◽  
Daphnia Magna ◽  
Danio Rerio ◽  
Pseudokirchneriella Subcapitata ◽  
High Toxicity

scholarly journals Effect of silver nanoparticles on human mesenchymal stem cell differentiation

2014 ◽  
Vol 5 ◽  
pp. 2058-2069 ◽  
Author(s):  
Christina Sengstock ◽  
Jörg Diendorf ◽  
Matthias Epple ◽  
Thomas A Schildhauer ◽  
Manfred Köller
Keyword(s):  
Silver Nanoparticles ◽  
Cell Differentiation ◽  
Osteogenic Differentiation ◽  
Stem Cell Differentiation ◽  
Laser Scanning Microscopy ◽  
Surgical Instruments ◽  
Dependent Manner ◽  
Low Concentration ◽  
Long Term Treatment

Background: Silver nanoparticles (Ag-NP) are one of the fastest growing products in nano-medicine due to their enhanced antibacterial activity at the nanoscale level. In biomedicine, hundreds of products have been coated with Ag-NP. For example, various medical devices include silver, such as surgical instruments, bone implants and wound dressings. After the degradation of these materials, or depending on the coating technique, silver in nanoparticle or ion form can be released and may come into close contact with tissues and cells. Despite incorporation of Ag-NP as an antibacterial agent in different products, the toxicological and biological effects of silver in the human body after long-term and low-concentration exposure are not well understood. In the current study, we investigated the effects of both ionic and nanoparticulate silver on the differentiation of human mesenchymal stem cells (hMSCs) into adipogenic, osteogenic and chondrogenic lineages and on the secretion of the respective differentiation markers adiponectin, osteocalcin and aggrecan. Results: As shown through laser scanning microscopy, Ag-NP with a size of 80 nm (hydrodynamic diameter) were taken up into hMSCs as nanoparticulate material. After 24 h of incubation, these Ag-NP were mainly found in the endo-lysosomal cell compartment as agglomerated material. Cytotoxicity was observed for differentiated or undifferentiated hMSCs treated with high silver concentrations (≥20 µg·mL−1 Ag-NP; ≥1.5 µg·mL−1 Ag+ ions) but not with low-concentration treatments (≤10 µg·mL−1 Ag-NP; ≤1.0 µg·mL−1 Ag+ ions). Subtoxic concentrations of Ag-NP and Ag+ ions impaired the adipogenic and osteogenic differentiation of hMSCs in a concentration-dependent manner, whereas chondrogenic differentiation was unaffected after 21 d of incubation. In contrast to aggrecan, the inhibitory effect of adipogenic and osteogenic differentiation was confirmed by a decrease in the secretion of specific biomarkers, including adiponectin (adipocytes) and osteocalcin (osteoblasts). Conclusion: Aside from the well-studied antibacterial effect of silver, little is known about the influence of nano-silver on cell differentiation processes. Our results demonstrate that ionic or nanoparticulate silver attenuates the adipogenic and osteogenic differentiation of hMSCs even at non-toxic concentrations. Therefore, more studies are needed to investigate the effects of silver species on cells at low concentrations during long-term treatment.

scholarly journals The impact of large terrestrial carnivores on Pleistocene ecosystems

2015 ◽  
Vol 113 (4) ◽  
pp. 862-867 ◽  
Author(s):  
Blaire Van Valkenburgh ◽  
Matthew W. Hayward ◽  
William J. Ripple ◽  
Carlo Meloro ◽  
V. Louise Roth
Keyword(s):  
Prey Size ◽  
Habitat Degradation ◽  
Terrestrial Ecosystems ◽  
Growth Data ◽  
Predator Prey ◽  
Body Sizes ◽  
Population Sizes ◽  
Potential Impact ◽  
The Impact ◽  
Ground Sloths

Large mammalian terrestrial herbivores, such as elephants, have dramatic effects on the ecosystems they inhabit and at high population densities their environmental impacts can be devastating. Pleistocene terrestrial ecosystems included a much greater diversity of megaherbivores (e.g., mammoths, mastodons, giant ground sloths) and thus a greater potential for widespread habitat degradation if population sizes were not limited. Nevertheless, based on modern observations, it is generally believed that populations of megaherbivores (>800 kg) are largely immune to the effects of predation and this perception has been extended into the Pleistocene. However, as shown here, the species richness of big carnivores was greater in the Pleistocene and many of them were significantly larger than their modern counterparts. Fossil evidence suggests that interspecific competition among carnivores was relatively intense and reveals that some individuals specialized in consuming megaherbivores. To estimate the potential impact of Pleistocene large carnivores, we use both historic and modern data on predator–prey body mass relationships to predict size ranges of their typical and maximum prey when hunting as individuals and in groups. These prey size ranges are then compared with estimates of juvenile and subadult proboscidean body sizes derived from extant elephant growth data. Young proboscideans at their most vulnerable age fall within the predicted prey size ranges of many of the Pleistocene carnivores. Predation on juveniles can have a greater impact on megaherbivores because of their long interbirth intervals, and consequently, we argue that Pleistocene carnivores had the capacity to, and likely did, limit megaherbivore population sizes.

scholarly journals Aquatic Toxicity Comparison of Silver Nanoparticles and Silver Nanowires

2015 ◽  
Vol 2015 ◽  
pp. 1-12 ◽  
Author(s):  
Eun Kyung Sohn ◽  
Seyed Ali Johari ◽  
Tae Gyu Kim ◽  
Jin Kwon Kim ◽  
Ellen Kim ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Daphnia Magna ◽  
Silver Nanowires ◽  
Aquatic Toxicity ◽  
Oryzias Latipes ◽  
Aquatic Environments ◽  
Silver Nanomaterials ◽  
Raphidocelis Subcapitata ◽  
Test Organisms ◽  
Test Fish

To better understand the potential ecotoxicological impact of silver nanoparticles (AgNPs) and silver nanowires (AgNWs) released into freshwater environments, the toxicities of these nanomaterials were assessed and compared using Organization for Economic Cooperation and Development (OECD) test guidelines, including a “Daphniasp., acute immobilization test,” “Fish, acute toxicity test,” and “freshwater alga and cyanobacteria, growth inhibition test.” Based on the estimated median lethal/effective concentrations of AgNPs and AgNWs, the susceptibility to the nanomaterials was different among test organisms (daphnia > algae > fish), suggesting that the AgNPs are classified as “category acute 1” forDaphnia magna, “category acute 2” forOryzias latipes, and “category acute 1” forRaphidocelis subcapitata, while the AgNWs are classified as “category acute 1” forDaphnia magna, “category acute 2” forOryzias latipes, and “category acute 2” forRaphidocelis subcapitata, according to the GHS (Globally Harmonized System of Classification and Labelling of Chemicals). In conclusion, the present results suggest that more attention should be paid to prevent the accidental or intentional release of silver nanomaterials into freshwater aquatic environments.

scholarly journals Defective defence in Daphnia daughters: silver nanoparticles inhibit anti-predator defence in offspring but not in maternal Daphnia magna

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Sarah Hartmann ◽  
Anna Beasley ◽  
Darya Mozhayeva ◽  
Carsten Engelhard ◽  
Klaudia Witte
Keyword(s):  
Silver Nanoparticles ◽  
Daphnia Magna ◽  
Predator Defence

scholarly journals Multigenerational Exposures of Daphnia Magna to Pristine and Aged Silver Nanoparticles: Epigenetic Changes and Phenotypical Ageing Related Effects

Small ◽  
2020 ◽  
Vol 16 (21) ◽  
pp. 2000301 ◽  
Author(s):  
Laura‐Jayne A. Ellis ◽  
Stephen Kissane ◽  
Elijah Hoffman ◽  
James B. Brown ◽  
Eugenia Valsami‐Jones ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Daphnia Magna ◽  
Epigenetic Changes

Potential impact of engineered silver nanoparticles in the control of aflatoxins, ochratoxin A and the main aflatoxigenic and ochratoxigenic species affecting foods

Food Control ◽  
2019 ◽  
Vol 101 ◽  
pp. 58-68 ◽  
Author(s):  
José V. Gómez ◽  
Andrea Tarazona ◽  
Fernando Mateo ◽  
Misericordia Jiménez ◽  
Eva M. Mateo
Keyword(s):  
Silver Nanoparticles ◽  
Ochratoxin A ◽  
Potential Impact

Toxicity of two types of silver nanoparticles to aquatic crustaceans Daphnia magna and Thamnocephalus platyurus

2012 ◽  
Vol 20 (5) ◽  
pp. 3456-3463 ◽  
Author(s):  
Irina Blinova ◽  
Jukka Niskanen ◽  
Paula Kajankari ◽  
Liina Kanarbik ◽  
Aleksandr Käkinen ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Daphnia Magna ◽  
Thamnocephalus Platyurus

scholarly journals Antimicrobial Efficacy of Low Concentration PVP-Silver Nanoparticles Deposited on DBD Plasma-Treated Polyamide 6,6 Fabric

Coatings ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 581 ◽  
Author(s):  
Ana Isabel Ribeiro ◽  
Dilara Senturk ◽  
Késia Karina Silva ◽  
Martina Modic ◽  
Uros Cvelbar ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Low Cost ◽  
Antimicrobial Effect ◽  
Bactericidal Effect ◽  
Dbd Plasma ◽  
Low Concentration ◽  
Log Reduction ◽  
Spray Method ◽  
Antibacterial Textiles ◽  
Fabric Surface

In this study, a low concentration (10 μg·mL−1) of poly(N-vinylpyrrolidone) (PVP)-coated silver nanoparticles (AgNPs) were deposited by spray and exhaustion (30, 70 and 100 °C) methods onto untreated and dielectric barrier discharge (DBD) plasma-treated polyamide 6,6 (PA66) fabric. DBD plasma-treated samples showed higher AgNP deposition than untreated ones for all methods. After five washing cycles, only DBD plasma-treated samples displayed AgNPs on the fabric surface. The best-performing method was exhaustion at 30 °C, which exhibited less agglomeration and the best antibacterial efficacy against S. aureus (4 log reduction). For E. coli, the antimicrobial effect showed good results in all the exhaustion samples (5 log reduction). Considering the spray method, only the DBD plasma-treated samples showed some bacteriostatic activity for both strains, but the AgNP concentration was not enough to have a bactericidal effect. Our results suggest DBD plasma may be a low cost and chemical-free method for the preparation of antibacterial textiles, allowing for the immobilization of a very low—but effective—concentration of AgNPs.

scholarly journals Influence of fragmentation and disturbance on the potential impact of feral predators on native fauna in Australian forest ecosystems

1996 ◽  
Vol 23 (4) ◽  
pp. 387 ◽  
Author(s):  
S. A. May ◽  
T. W. Norton
Keyword(s):  
Forest Ecosystems ◽  
Prey Species ◽  
Prey Availability ◽  
Current Knowledge ◽  
Native Forest ◽  
Feral Cat ◽  
Predator Prey ◽  
Small Prey ◽  
Potential Impact ◽  
The Impact

The current knowledge is reviewed of the diet and predator–prey relationships of the feral cat (Felis catus), fox (Vulpes vulpes) and dingo (Canis familiaris dingo) (including wild dogs). The effect of forest fragmentation by roads on the use of native forest ecosystems by these species and the significance of this for native fauna is considered. The cat, fox and dingo are significant predators in Australia that interact with native fauna in various ways, including predation, competition for resources, and transmission of disease. On the basis of current knowledge, it is clear that the nature and impact of predation by the cat, fox and dingo on native fauna are primarily determined by prey availability, although there are exceptions to this rule. Generally, dingoes prey upon large to medium-sized prey species (e.g. wallabies, common wombats, and possums), foxes prey upon medium-sized to small prey (e.g. possums and rats) and consume a significant component of scavenged material and vegetation, while cats also prey upon medium-sized to small prey, but may have a greater proportion of reptiles and birds in their diet. The cat is generally considered to be an opportunistic predator and to have contributed to the demise of a number of mammals. The fox is considered more of a threat to small native mammals and it has been asserted that all species of mammals that fall within the critical weight range (CWR) of 120–5000 g are at risk of local extinction when the fox is present. The severity of the impact of the dingo upon the native fauna is considered to be minimal, at least in comparison with the impact that the cat and fox can have on populations. The dingo is not considered a threat to CWR mammals in undisturbed environments. The fox, feral cat and dingo are all considered to have the ability to selectivity prey upon species and, to some extent, individual sexes and age-classes of a number of larger prey species. Although many of Australia's forested areas are relatively heavily fragmented by roads, there are no published studies specifically investigating the use of roads by feral predators. Information on the distribution and abundance of foxes, cats and dingoes in these ecosystems, their ecology and their impact on native fauna is particularly limited. Further, the extent to which roads influence the distribution and abundance of these species and the consequences of these for native fauna are poorly known. One of the most important research needs is to establish the relative impact that exotic predators may have on native fauna under varying degrees of road construction within native forests. For example, are areas with and without roads in forests used differently by exotic predators and what is the significance of this in terms of the potential impact on fauna? The extent to which feral predators forage away from roads needs further investigation, as does the rates of predation within edges, because this may have several consequences for the design, location and size of retained strips and wildlife corridors as well as restoration programmes. Further observations on regional differences influencing predator–prey interactions are required, as is research on the potential impacts on native fauna resulting from prey selection in forests subjected to various degrees of fragmentation and modification.

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