Chinese scientists: citation of Moscow University.
http://5bio5.blogspot.com/2013/09/citation-of-moscow-university.html
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The Citation, visible at the web-site of PubMed:
Abstract
Silica nanoparticles (SiNPs) have been widely used in biomedical and biotechnological applications. Environmental exposure to nanomaterials is inevitable as they become part of our daily life. Therefore, it is necessary to investigate the possible toxic effects of SiNPs exposure. In this study, zebrafish embryos were treated with SiNPs (25, 50, 100, 200 µg/mL) during 4–96 hours post fertilization (hpf). Mortality, hatching rate, malformation and whole-embryo cellular death were detected. We also measured the larval behavior to analyze whether SiNPs had adverse effects on larvae locomotor activity. The results showed that as the exposure dosages increasing, the hatching rate of zebrafish embryos was decreased while the mortality and cell death were increased. Exposure to SiNPs caused embryonic malformations, including pericardial edema, yolk sac edema, tail and head malformation. The larval behavior testing showed that the total swimming distance was decreased in a dose-dependent manner. The lower dose (25 and 50 µg/mL SiNPs) produced substantial hyperactivity while the higher doses (100 and 200 µg/mL SiNPs) elicited remarkably hypoactivity in dark periods. In summary, our data indicated that SiNPs caused embryonic developmental toxicity, resulted in persistent effects on larval behavior.
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Introduction
Silica nanoparticles (SiNPs) have been found extensive applications in biomedical and biotechnological fields, such as medical diagnostics, drug delivery, gene therapy, tracking and imaging in vivo [1], [2], [3], [4](Li, 2012 #1). SiNPs is in the top five of nanomaterials explicitly referenced in nanotech-based comsumer products [5]. The toxicity research of nanomaterials is getting great attention as the increasing exposure of nanomaterials on human and ecological environment [6], [7]. One of the challenges in the field of nanotechnology is environmental health and safety (EHS), which is focusing on the consideration of the properties of engineered nanomaterials (ENMs) that could pose hazards to the environment and human beings [8].
Currently, zebrafish is emerging as a correlative in vivo vertebrate model for nano EHS studies due to their lower husbandry cost, optical transparency and high degree of genomic homology to humans [9], [10]. The zebrafish model has been reported for assessing of a wide array of nanomaterials including metal or metal oxide nanoparticles, carbon-based nanomaterials and polymers [11], [12],[13]. However, most studies conducted the embryonic toxicity induced by nanomaterials rather than assessing the changes of larval behavior. Zebrafish is also a popular model for the study of nervous system development [14]. New-hatched, larval zebrafish have a rich behavioral response. By six days post fertilization (dpf), the larvae are mature swimmers with functioning sensory and motor systems allowing studies of locomotor, escape, goal-oriented, and optomotor responses [15]. Thus, it is necessary to perform larval behavior as well as embryonic toxicity as evaluating nanomaterials. Despite the increasing popularity of SiNPs in biological applications, there is still lack of in vitro and in vivo data for predictive and correlative SiNPs toxicity. So far, only a few studies investigated the assessment of SiNPs toxicity using zebrafish model [16], [17]. Therefore, more studies are needed to better understand the toxicity of SiNPs in both embryos and larvae of zebrafish.
To our best knowledge, this is the first study to illustrate the embryonic toxicity and the alteration of larvae locomotor activity after zebrafish embryos exposure to SiNPs for 4–96 hours post fertilization (hpf). Prior to undertaking in vitro toxicity experiments, the characterization of SiNPs, which is essential for nanotoxicity studies, was performed by transmission electron microscope (TEM) and dynamic light scattering (DLS) measurements. To investigate the toxic effects of zebrafish embryos induced by SiNPs, we conducted a sequence of assessments including embryonic mortality, hatching rate, malformation and whole-embryo cellular death. We also determined the total swimming distance for light-dark optomotor responses to analyze whether SiNPs exposure could alter locomotor activity in zebrafish larvae. Taken embryonic toxicity and larval behavior together as indicators of evaluating SiNPs toxicity, will be more beneficial and comprehensive for the nano EHS studies and safety evaluation.
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Materials and Methods
Silica Nanoparticles Preparation and Characterization
SiNPs were prepared using the Stöber method [18]. Briefly, 2.5 mL of tetraethylorthosilicate (TEOS) (Sigma, USA) was added to premixed ethanol solution (50 mL) containing ammonia (2 mL) and water (1 mL). The reaction mixture was kept at 40°C fo
http://5bio5.blogspot.com/2013/09/citation-of-moscow-university.html
**
The Citation, visible at the web-site of PubMed:
Toxic Effects of Silica Nanoparticles on Zebrafish Embryos and Larvae
4 days ago - Nanotoxicology 5: 168–181. [PubMed]. 6. Ostroumov SA, Kotelevtsev SV (2011) Toxicology of nanomaterials and environment. Ecologica 18: 3–10.
Paper that was cited:
Ostroumov SA, Kotelevtsev SV (2011) Toxicology of nanomaterials and environment. Ecologica 18: 3–10.
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More info on the paper that cited:
PLoS One. 2013; 8(9): e74606.
Published online 2013 September 18. doi: 10.1371/journal.pone.0074606
PMCID: PMC3776836
Toxic Effects of Silica Nanoparticles on Zebrafish Embryos and Larvae
1School of Public Health, Capital Medical University, Beijing, P.R. China
2Beijing Key Laboratory of Environmental Toxicology, Capital Medical University, Beijing, P.R. China
3Institute of Disease Control and Prevention, Academy of Military Medical Sciences, Beijing, P.R. China
4School of Public Health and Primary Care, Chinese University of Hong Kong, Hong Kong, P.R. China
Dowling College, United States of America
#Contributed equally.
* E-mail: pengsq@hotmail.com (SQP); Email: zwsun@hotmail.com (ZWS)
Competing Interests: The authors have declared that no competing interests exist.
Conceived and designed the experiments: JCD YBY ZWS. Performed the experiments: JCD YBY HQS. Analyzed the data: JCD YBY CXG LWT. Contributed reagents/materials/analysis tools: PLH XQZ SQP ZWS. Wrote the paper: JCD YBY ZWS.
Vishal Shah, Editor
Abstract
Silica nanoparticles (SiNPs) have been widely used in biomedical and biotechnological applications. Environmental exposure to nanomaterials is inevitable as they become part of our daily life. Therefore, it is necessary to investigate the possible toxic effects of SiNPs exposure. In this study, zebrafish embryos were treated with SiNPs (25, 50, 100, 200 µg/mL) during 4–96 hours post fertilization (hpf). Mortality, hatching rate, malformation and whole-embryo cellular death were detected. We also measured the larval behavior to analyze whether SiNPs had adverse effects on larvae locomotor activity. The results showed that as the exposure dosages increasing, the hatching rate of zebrafish embryos was decreased while the mortality and cell death were increased. Exposure to SiNPs caused embryonic malformations, including pericardial edema, yolk sac edema, tail and head malformation. The larval behavior testing showed that the total swimming distance was decreased in a dose-dependent manner. The lower dose (25 and 50 µg/mL SiNPs) produced substantial hyperactivity while the higher doses (100 and 200 µg/mL SiNPs) elicited remarkably hypoactivity in dark periods. In summary, our data indicated that SiNPs caused embryonic developmental toxicity, resulted in persistent effects on larval behavior.
Go to:
Introduction
Silica nanoparticles (SiNPs) have been found extensive applications in biomedical and biotechnological fields, such as medical diagnostics, drug delivery, gene therapy, tracking and imaging in vivo [1], [2], [3], [4](Li, 2012 #1). SiNPs is in the top five of nanomaterials explicitly referenced in nanotech-based comsumer products [5]. The toxicity research of nanomaterials is getting great attention as the increasing exposure of nanomaterials on human and ecological environment [6], [7]. One of the challenges in the field of nanotechnology is environmental health and safety (EHS), which is focusing on the consideration of the properties of engineered nanomaterials (ENMs) that could pose hazards to the environment and human beings [8].
Currently, zebrafish is emerging as a correlative in vivo vertebrate model for nano EHS studies due to their lower husbandry cost, optical transparency and high degree of genomic homology to humans [9], [10]. The zebrafish model has been reported for assessing of a wide array of nanomaterials including metal or metal oxide nanoparticles, carbon-based nanomaterials and polymers [11], [12],[13]. However, most studies conducted the embryonic toxicity induced by nanomaterials rather than assessing the changes of larval behavior. Zebrafish is also a popular model for the study of nervous system development [14]. New-hatched, larval zebrafish have a rich behavioral response. By six days post fertilization (dpf), the larvae are mature swimmers with functioning sensory and motor systems allowing studies of locomotor, escape, goal-oriented, and optomotor responses [15]. Thus, it is necessary to perform larval behavior as well as embryonic toxicity as evaluating nanomaterials. Despite the increasing popularity of SiNPs in biological applications, there is still lack of in vitro and in vivo data for predictive and correlative SiNPs toxicity. So far, only a few studies investigated the assessment of SiNPs toxicity using zebrafish model [16], [17]. Therefore, more studies are needed to better understand the toxicity of SiNPs in both embryos and larvae of zebrafish.
To our best knowledge, this is the first study to illustrate the embryonic toxicity and the alteration of larvae locomotor activity after zebrafish embryos exposure to SiNPs for 4–96 hours post fertilization (hpf). Prior to undertaking in vitro toxicity experiments, the characterization of SiNPs, which is essential for nanotoxicity studies, was performed by transmission electron microscope (TEM) and dynamic light scattering (DLS) measurements. To investigate the toxic effects of zebrafish embryos induced by SiNPs, we conducted a sequence of assessments including embryonic mortality, hatching rate, malformation and whole-embryo cellular death. We also determined the total swimming distance for light-dark optomotor responses to analyze whether SiNPs exposure could alter locomotor activity in zebrafish larvae. Taken embryonic toxicity and larval behavior together as indicators of evaluating SiNPs toxicity, will be more beneficial and comprehensive for the nano EHS studies and safety evaluation.
Go to:
Materials and Methods
Silica Nanoparticles Preparation and Characterization
SiNPs were prepared using the Stöber method [18]. Briefly, 2.5 mL of tetraethylorthosilicate (TEOS) (Sigma, USA) was added to premixed ethanol solution (50 mL) containing ammonia (2 mL) and water (1 mL). The reaction mixture was kept at 40°C fo