scholarly journals Comparison of Genotoxicity and Pulmonary Toxicity Study of Modified SiO2 Nanomaterials

2021 ◽  
Vol 11 (24) ◽  
pp. 11990
Author(s):  
Yng-Tay Chen ◽  
Po-Yi Lue ◽  
Po-Wei Chen ◽  
Pin-Ju Chueh ◽  
Fuu-Jen Tsai ◽  
...  

Surface-modified nano-SiO2 is a common additive in many products. However, the safety of nano-SiO2 products under various modifications is still unclear. In this study, we investigated the genotoxicity and acute pulmonary toxicity of nano-SiO2 with or without modification. The samples used in this study included: sample A (SA, 55.16 nm, 411.3 mg/mL), modified sample A (mSA, 82.29 nm, 37.7 mg/mL), sample B (SB, 22 nm, 358.0 mg/mL), and modified sample B (mSB, 86.64 nm, 37.7 mg/mL). In the genotoxicity study, we conducted an Ames test, chromosomal aberration test (CA), and a micronucleus (MN) test. The SA, mSA, and mSB groups showed negative results in all these genotoxicity tests. Only SB showed a weakly positive reaction in these assays, but the genotoxicity could be reversed after S9 metabolism or modification. In the acute pulmonary toxicity test, the rats were given an intratracheal instillation (IT) (0.5 mL/kg) of diluted samples and sacrificed after 1 or 14 days. The mortality rate, number of leukocytes and cytokines of TNF-α in the bronchoalveolar lavage fluid (BALF), and the pathology in the lungs were determined. The results revealed that mSA posed acute toxicity in rats. After modification, the pulmonary toxicity was increased in mSA but decreased in mSB on Day 1, and no significant difference was observed on Day 14. In conclusion, there was no observed genotoxicity in either SA or SB, while mSA posed acute inhalation toxicity to rats that decreased in mSB after modification. This indicates that the decrease in pH level in SA and decrease in the solid content in SB are considered after the trifluorosilane surface-modified amorphous nano-silica.

2021 ◽  
Vol 22 (9) ◽  
pp. 4635
Author(s):  
Taisuke Tomonaga ◽  
Hiroto Izumi ◽  
Yukiko Yoshiura ◽  
Chinatsu Nishida ◽  
Kazuhiro Yatera ◽  
...  

This work studies the relationship between lung inflammation caused by nanomaterials and surfactant protein D (SP-D) kinetics and investigates whether SP-D can be a biomarker of the pulmonary toxicity of nanomaterials. Nanomaterials of nickel oxide and cerium dioxide were classified as having high toxicity, nanomaterials of two types of titanium dioxides and zinc oxide were classified as having low toxicity, and rat biological samples obtained from 3 days to 6 months after intratracheal instillation of those nanomaterials and micron-particles of crystalline silica were used. There were different tendencies of increase between the high- and low-toxicity materials in the concentration of SP-D in bronchoalveolar-lavage fluid (BALF) and serum and in the expression of the SP-D gene in the lung tissue. An analysis of the receiver operating characteristics for the toxicity of the nanomaterials by SP-D in BALF and serum showed a high accuracy of discrimination from 1 week to 3 or 6 months after exposure. These data suggest that the differences in the expression of SP-D in BALF and serum depended on the level of lung inflammation caused by the nanomaterials and that SP-D can be biomarkers for evaluating the pulmonary toxicity of nanomaterials.


Nanomaterials ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 1563
Author(s):  
Taisuke Tomonaga ◽  
Hiroto Izumi ◽  
Takako Oyabu ◽  
Byeong-Woo Lee ◽  
Masaru Kubo ◽  
...  

This work determines whether cytokine-induced neutrophil chemoattractants (CINC)-1, CINC-2 and CINC-3 can be markers for predicting high or low pulmonary toxicity of nanomaterials (NMs). We classified NMs of nickel oxide (NiO) and cerium dioxide (CeO2) into high toxicity and NMs of two types of titanium dioxides (TiO2 (P90 and rutile)) and zinc oxide (ZnO) into low toxicity, and we analyzed previous data of CINCs in bronchoalveolar lavage fluid (BALF) of rats from three days to six months after intratracheal instillation (0.2 and 1.0 mg) and inhalation exposure (0.32–10.4 mg/m3) of materials (NiO, CeO2, TiO2 (P90 and rutile), ZnO NMs and micron-particles of crystalline silica (SiO2)). The concentration of CINC-1 and CINC-2 in BALF had different increase tendency between high and low pulmonary toxicity of NMs and correlated with the other inflammatory markers in BALF. However, CINC-3 increased only slightly in a dose-dependent manner compared with CINC-1 and CINC-2. Analysis of receiver operating characteristics for the toxicity of NMs by CINC-1 and CINC-2 showed the most accuracy of discrimination of the toxicity at one week or one month after exposure and CINC-1 and CINC-2 in BALF following intratracheal instillation of SiO2 as a high toxicity could accurately predict the toxicity at more than one month after exposure. These data suggest that CINC-1 and CINC-2 may be useful biomarkers for the prediction of pulmonary toxicity of NMs relatively early in both intratracheal instillation and inhalation exposure.


2019 ◽  
Vol 3 (1) ◽  
Author(s):  
Tim Lenz-Habijan ◽  
Pervinder Bhogal ◽  
Catrin Bannewitz ◽  
Ralf Hannes ◽  
Hermann Monstadt ◽  
...  

Abstract Background Flow diverters (FDs) are widely used in the treatment of intracranial aneurysms, but the required medication increases the risk of haemorrhagic complications and limits their use in the acute setting. Surface modified FDs may limit the need for dual antiplatelet therapy (DAPT). Hydrophilic polymer coating (HPC) may reduce the need of medication. Methods This explorative study, approved by the local authorities and the local welfare committee, compared stent behaviour and overall tissue response between HPC-coated FDs and uncoated FDs, both implanted into the common carotid arteries of eight New Zealand white rabbits. Endothelialisation, inflammatory response, and performance during implantation were assessed. Angiographic follow-up was performed to observe the patency of the devices after implantation and after 30 days. Histological examinations were performed at 30 days to assess foreign body reaction and endothelialisation. Kruskal-Wallis and Wilcoxon tests were used to compare non-parametric variables. Results Angiography showed that both coated and uncoated FDs performed well during implantation. All devices remained patent during immediate follow-up and after 30 days. Histopathology showed no significant difference in inflammation within the vessel wall between the two cohorts (2.12 ± 0.75 vs. 1.96 ± 0.79, p = 0.7072). Complete endothelialisation of the stent struts was seen with very similar (0.04 ± 0.02 mm vs. 0.04 ± 0.03 mm, p = 0.892) neoendothelial thickness between the two cohorts after 30 days. Conclusion Taking into account the limitation in sample size, non-significant differences between the HPC-coated and uncoated FDs regarding implantation, foreign body response, and endothelialisation were found.


Author(s):  
Julien Favresse ◽  
Jean-Louis Bayart ◽  
Damien Gruson ◽  
Sergio Bernardini ◽  
Aldo Clerico ◽  
...  

Abstract Cardiac troponins (cTn) are the preferred biomarkers for the evaluation of myocardial injury and play a key role in the diagnosis of acute myocardial infarction (MI). Pre-analytical or analytical issues and interferences affecting troponin T and I assays are therefore of major concern given the risk of misdiagnosis. False positive troponin results have been related to various interferences including anti-troponin antibodies, heterophilic antibodies, or elevated alkaline phosphatase level. On the other hand, false negative results have been reported in the case of a large biotin intake. These interferences are characterized with erroneous but reproducible troponin results. Of interest, non-reproducible results have also been reported in the literature. In other words, if the sample is reanalyzed a second time, a significant difference in troponin results will be observed. These interferences have been named “fliers” or “outliers”. Compared to the biotin interference that received major attention in the literature, troponin outliers are also able to induce harmful clinical consequences for the patient. Moreover, the prevalence of outliers in recent studies was found to be higher (0.28–0.57%) compared to the biotin interference. The aim of this systematic review is to warn clinicians about these non-reproducible results that may alter their clinical judgment. Four case reports that occurred in the Clinique of Saint-Luc Bouge are presented to attest this point. Moreover, we aimed at identifying the nature of these non-reproducible troponin results, determining their occurrence, and describing the best way for their identification.


2005 ◽  
Vol 289 (5) ◽  
pp. L890-L895 ◽  
Author(s):  
Cara Geary ◽  
Henry Akinbi ◽  
Tom Korfhagen ◽  
Jean-Etienne Fabre ◽  
Richard Boucher ◽  
...  

Purinergic receptors are expressed throughout the respiratory system in diverse cell types. The efficiency of mucus clearance in the airways, the cascade leading to tissue injury, and inflammation are modulated by autocrine/paracrine release of nucleotides and signaling by purinergic receptors. We assessed the role of purinergic receptors in innate host defense of the lung in vivo by infecting mice deficient in P2Y1, P2Y2, or both receptors with intratracheal instillation of Pseudomonas aeruginosa. After P. aeruginosa challenge, all double knockout (P2Y1/P2Y2−/−) mice succumbed within 30 h of challenge, whereas 85% of the wild-type mice survived. Thirty-three percent of wild-type mice survived beyond 96 h. Single knockout mice, P2Y1−/−, or P2Y2−/−, exhibited intermediate survivals. Twenty-four hours following intratracheal instillation of a sublethal dose of P. aeruginosa, the level of total protein in bronchoalveolar lavage fluid was 1.8-fold higher in double knockout than in wild-type mice ( P < 0.04). Total cell count in bronchoalveolar lavage fluids at 4 h and levels of IL-6 and macrophage inflammatory protein-2 in lung homogenates at 24 h postchallenge were significantly reduced in P2Y1/P2Y2−/− mice relative to wild-type mice. These findings suggest that purinergic receptors exert a protective role against infection of the lungs by P. aeruginosa by decreasing protein leak and enhancing proinflammatory cytokine response.


2013 ◽  
Vol 38 (3) ◽  
pp. 471-475 ◽  
Author(s):  
Jung-Taek Kwon ◽  
Young-Su Yang ◽  
Min-Sung Kang ◽  
Gyun-Baek Seo ◽  
Dong Hun Lee ◽  
...  

Open Medicine ◽  
2015 ◽  
Vol 10 (1) ◽  
Author(s):  
Hyo Yeong Ahn ◽  
Jeong Su Cho ◽  
Yeong Dae Kim ◽  
Hoseok I ◽  
Yeon Ji Kim ◽  
...  

AbstractChemical pleurodesis is an effective treatment modality to reduce recurrence of malignant effusion. Several agents have been used in chemical pleurodesis but, it is not yet clear which is better. Eighteen Sprague- Dawley rats were used and classified into three groups: a group intrapleurally injected normal saline (group A, n=6), 400mg/kg talc (group B, n=6), and 9mg/kg mistletoe extraction (ME) (group C, n=6). Autopsy was performed to evaluate the pleural adhesion, pathologic examination of pleura and lung and bronchoalveolar lavage fluid analysis 4 weeks after pleurodesis. Both group B and C showed an obvious pleural adhesion and there was no significant difference in grade of pleural adhesion between two groups (p=0.58). The parietal pleural thickness in talc group than ME group was significantly thicker (p=0.002) and the visceral pleura of talc group showed marked foreign body reaction with fibrosis and many multinucleated giant cells associated with talc crystal. This study suggests that pleurodesis using ME in condition without malignancy has comparable effect to pleurodesis using talc. However, additional experimental study in large animal or clinical trials would be required to prove a safety and an efficacy of pleurodesis using ME.


2005 ◽  
Vol 63 (2b) ◽  
pp. 375-379 ◽  
Author(s):  
Maria José Sá ◽  
Lucinda Sequeira ◽  
Maria Edite Rio ◽  
Edward J. Thompson

We assessed the frequency of cerebrospinal fluid (CSF) restricted oligoclonal IgG bands (IgG-OCB) in Portuguese multiple sclerosis (MS) patients and its relationship with outcome. Paired CSF/serum samples of 406 patients with neurological disorders were submitted to isoelectric focusing with immunodetection of IgG. Ninety-two patients had definite MS; non-MS cases were assembled in groups inflammatory/infectious diseases (ID, n=141) and other/controls (OD, n=173). We found in the MS group: mean duration, 38.9 months; clinically isolated syndromes, 24%; relapsing/remitting course (RR), 65%; in RR patients the mean EDSS was 2.1 and the mean index of progression was 0.31. Positive patterns significantly predominated in MS (82.6%; ID, 40.4%; OD, 3.5%). The sensitivity and the specificity of positive IgG-OCB for MS diagnosis was 82.6% and 79.9%, respectively. The sole statistically significant difference in the MS group was the lower progression index observed in negative cases. We conclude that the frequency of positive IgG-OCB patterns in our MS patients fits most values reported in the literature, and that negative results indicate benign disease.


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