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https://www.readbyqxmd.com/read/29332272/comparative-study-of-selenium-and-selenium-nanoparticles-with-reference-to-acute-toxicity-biochemical-attributes-and-histopathological-response-in-fish
#1
Neeraj Kumar, Kishore Kumar Krishnani, Narendra Pratap Singh
Recent studies have demonstrated that selenium (Se) and selenium nanoparticles (Se-NPs) exhibited toxicity at a higher concentration. The lethal concentration of Se and Se-NPs was estimated as 5.29 and 3.97 mg/L at 96 h in Pangasius hypophthalmus. However, the effect of different definite concentration of Se (4.5, 5.0, 5.5, and 6.0 mg/L) and Se-NPs (2.5, 3.0, 3.5, and 4.0 mg/L) was decided for acute experiment. Selenium and Se-NPs alter the biochemical attributes such as anti-oxidative status [catalase (CAT), superoxide dismutase (SOD), and glutathione-S-transferase (GST) activities], neurotransmitter enzyme, cellular metabolic enzymes, stress marker, and histopathology of P...
January 13, 2018: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/29331881/ameliorative-role-of-genistein-against-age-dependent-chronic-arsenic-toxicity-in-murine-brains-via-the-regulation-of-oxidative-stress-and-inflammatory-signaling-cascades
#2
Sukanya Saha, Pritam Sadhukhan, Sushweta Mahalanobish, Sayanta Dutta, Parames C Sil
Brain is highly prone to oxidative damage due to its huge lipid content and extensive energy requirements. Exogenous insult in brain via oxidative injury can lead to severe pathophysiological conditions. Age-dependent deterioration of normal brain functions is also noteworthy. Genistein, a polyphenolic isoflavonoid, obtained from the soy plant, is well known to protect against several diseased conditions. Here, in this study chronic brain toxicity model was developed using oral administration of arsenic for 90 days in adult and aged murines...
December 12, 2017: Journal of Nutritional Biochemistry
https://www.readbyqxmd.com/read/29331836/effects-of-zno-nanoparticles-in-the-caspian-roach-rutilus-rutilus-caspicus
#3
K Khosravi-Katuli, G Lofrano, H Pak Nezhad, A Giorgio, M Guida, F Aliberti, A Siciliano, M Carotenuto, E Galdiero, E Rahimi, G Libralato
Most studies investigating the toxicity of zinc oxide nanoparticles (ZnO NPs) focused on the effect of size, whereas exposure concentration and duration remained poorly understood. In this study, the effect of acute and sub-acute exposures of ZnO NPs on Zn compartmentalization and biomarkers' expression were investigated in Rutilus rutilus caspicus (Caspian roach) considering various exposure scenarios: i) the assessment of the concentration-response curves and median lethal concentration (LC50); ii) the assessment of the effects of organisms exposed at LC50 value and one tenth of LC50 value of ZnO NPs suspensions for 4 d and 28 d, respectively; iii) the assessment of 14 d depuration period...
January 11, 2018: Science of the Total Environment
https://www.readbyqxmd.com/read/29331773/impact-of-co-exposure-of-aldrin-and-titanium-dioxide-nanoparticles-at-biochemical-and-molecular-levels-in-zebrafish
#4
Reena C Jhamtani, Saurabh Shukla, P Sivaperumal, M S Dahiya, Rakhi Agarwal
Aldrin (ALD), a persistent-organic-pollutant (POP), an organochlorine-cyclodiene-pesticide is highly toxic in nature. Titanium dioxide nanoparticles (TNP) are widely used for various industrial applications. Despite the remarkable research on pesticide toxicity, the work with impact of nanoparticles on POP has been dealt with marginally. Chemicals co-exist in the environment and exhibit interactive effects. An investigation was carried out to evaluate the individual and combined effects of ALD (6 ppm) and TNP (60 ppm) exposure at sub-lethal concentration for 24 h in zebrafish...
December 27, 2017: Environmental Toxicology and Pharmacology
https://www.readbyqxmd.com/read/29331717/in%C3%A2-vitro-dermal-bioaccessibility-of-selected-metals-in-contaminated-soil-and-mine-tailings-and-human-health-risk-characterization
#5
Laura T Chaparro Leal, Mert Guney, Gerald J Zagury
Dermal exposure to contaminated sites has generally received less attention than oral/inhalation exposure due to limited exposure scenarios and less perceived potential for toxicity, however, the risk can be significant for specific contaminants and scenarios. The present study aims to (1) measure Cr, Ni, Pb, and Zn contamination in soil and mine tailings samples (n = 7), (2) determine the dermal bioaccessibility of these metals via in vitro tests using two synthetic sweat formulations (EN 1811; NIHS 96-10), and (3) obtain dermal absorbed doses (DADs) for children's and adults' exposure scenarios and compare them to derived dermal reference values...
January 4, 2018: Chemosphere
https://www.readbyqxmd.com/read/29331715/toxicokinetics-of-zn-and-cd-in-the-earthworm-eisenia-andrei-exposed-to-metal-contaminated-soils-under-different-combinations-of-air-temperature-and-soil-moisture-content
#6
M Nazaret González-Alcaraz, Susana Loureiro, Cornelis A M van Gestel
This study evaluated how different combinations of air temperature (20 °C and 25 °C) and soil moisture content (50% and 30% of the soil water holding capacity, WHC), reflecting realistic climate change scenarios, affect the bioaccumulation kinetics of Zn and Cd in the earthworm Eisenia andrei. Earthworms were exposed for 21 d to two metal-contaminated soils (uptake phase), followed by 21 d incubation in non-contaminated soil (elimination phase). Body Zn and Cd concentrations were checked in time and metal uptake (k1) and elimination (k2) rate constants determined; metal bioaccumulation factor (BAF) was calculated as k1/k2...
January 8, 2018: Chemosphere
https://www.readbyqxmd.com/read/29331652/salinomycin-induces-primary-chicken-cardiomyocytes-death-via-mitochondria-mediated-apoptosis
#7
Xiuge Gao, Yani Zheng, Xiangchun Ruan, Hui Ji, Lin Peng, Dawei Guo, Shanxiang Jiang
Salinomycin, as a polyether ionophore antibiotic, is extensively used as a feed additive against coccidiosis in poultry and as a growth promoter of ruminants worldwide. Owing to its narrow therapeutic index, numerous intoxication have been reported in target/non-target animals by overdosage, misuse or drug interactions as well as human who consumed salinomycin accidently. Salinomycin-induced cardiotoxicity in chicken and non-target animals is considered as a major contributor to animal death. In the current study, we aim to elucidate the underlying mechanism of its myocardial toxicity using primary chicken myocardial cell as an in vitro model...
January 10, 2018: Chemico-biological Interactions
https://www.readbyqxmd.com/read/29331621/silver-ion-enhanced-particle-specific-cytotoxicity-of-silver-nanoparticles-and-effect-on-the-production-of-extracellular-secretions-of-phanerochaete-chrysosporium
#8
Zhenzhen Huang, Piao Xu, Guiqiu Chen, Guangming Zeng, Anwei Chen, Zhongxian Song, Kai He, Lei Yuan, Hui Li, Liang Hu
This study investigated the influence of silver ions (Ag+) on the cytotoxicity of silver nanoparticles (AgNPs) in Phanerochaete chrysosporium and noted the degree of extracellular secretions in response to the toxicant's stress. Oxalate production was elicited with moderate concentrations of 2,4-dichlorophenol (2,4-DCP) and AgNPs reaching a plateau at 10 mg/L and 10 μM, respectively. Increased oxalate accumulation was accompanied by higher activities of manganese peroxidase (MnP) and lignin peroxidase (LiP)...
December 30, 2017: Chemosphere
https://www.readbyqxmd.com/read/29331520/vitamin-c-attenuates-biochemical-and-genotoxic-damage-in-common-carp-cyprinus-carpio-upon-joint-exposure-to-combined-toxic-doses-of-fipronil-and-buprofezin-insecticides
#9
Madiha Ghazanfar, Sana Shahid, Irfan Zia Qureshi
In the present study, potential protective role of Vitamin C (l-ascorbic acid) was investigated in aquaria acclimated common carp (Cyprinus carpio) following exposure for 96 h to combined toxic doses of fipronil (FP) and buprofezin (BPFN) insecticides in combination (FP: 200 μg/L; 4.57 × 10-7 mol/L and BPFN: 50 mg/L; 1.64 × 10-4 mol/L). At end of 96 h exposure, fish were supplemented with low (25 mg/L) and high (50 mg/L) doses of Vitamin C, added once daily to aquaria water for continuous three weeks...
January 5, 2018: Aquatic Toxicology
https://www.readbyqxmd.com/read/29330822/biochemical-changes-in-mussels-submitted-to-different-time-periods-of-air-exposure
#10
Madalena Andrade, Amadeu Soares, Etelvina Figueira, Rosa Freitas
Intertidal species face multiple stressors on a daily basis due to their particular habitat. The submergence at high tide in the aquatic environment and emergence at low tide to the aerial environment, associated with a wide variation of abiotic parameters, along with anthropogenic contamination are some of the daily stresses that these organisms are exposed to. With such a dynamic environment, organisms developed strategies that allow them to avoid or tolerate these stressors. Among these species, bivalves are some of the most hypoxia tolerant, being commonly used as a biomonitoring tool due to their capacity to accumulate pollutants from the environment and reflect the imposed toxic impacts...
January 13, 2018: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/29330218/a-study-on-pharmacokinetics-of-bosentan-with-systems-modeling-part-1-translating-systemic-plasma-concentration-to-liver-exposure-in-healthy-subjects
#11
Rui Li, Mark Niosi, Nathaniel Johnson, David A Tess, Emi Kimoto, Jian Lin, Xin Yang, Keith A Riccardi, Sangwoo Ryu, Ayman F El-Kattan, Tristan S Maurer, Larry M Tremaine, Li Di
Understanding liver exposure of hepatic transporter substrates in clinical studies is often critical as it typically governs pharmacodynamics, drug-drug interactions, and toxicity for certain drugs. However, this is a challenging task since there is currently no easy method to directly measure drug concentration in the human liver. Using bosentan as an example, a new approach has been demonstrated to estimate liver exposure based on observed systemic pharmacokinetics from clinical studies using physiologically-based pharmacokinetic modeling...
January 12, 2018: Drug Metabolism and Disposition: the Biological Fate of Chemicals
https://www.readbyqxmd.com/read/29329878/course-dose-and-stage-dependent-toxic-effects-of-prenatal-dexamethasone-exposure-on-fetal-articular-cartilage-development
#12
Ze Chen, Zhe Zhao, Yunzepeng Li, Xingyu Zhang, Bin Li, Liaobin Chen, Hui Wang
Dexamethasone, a synthetic long-acting glucocorticoid, is routinely used for treating mothers at risk for preterm delivery. However, intrauterine overexposure to glucocorticoids induces low birth weight and cartilage dysplasia in offspring. Also, the "critical window" and safe dose of this treatment are largely unknown. This study investigated the course-, dose-, and stage-dependent toxic effects and the possible mechanisms of prenatal dexamethasone exposure (PDE) on fetal development and articular cartilage development...
January 9, 2018: Toxicology Letters
https://www.readbyqxmd.com/read/29329860/ethyl-carbamate-an-emerging-food-and-environmental-toxicant
#13
REVIEW
Vemana Gowd, Hongming Su, Petr Karlovsky, Wei Chen
Ethyl carbamate (EC), a chemical substance widely present in fermented food products and alcoholic beverages, has been classified as a Group 2A carcinogen by the International Agency for Research on Cancer (IARC). New evidence indicates that long-term exposure to EC may cause neurological disorders. Formation of EC in food and its metabolism have therefore been studied extensively and analytical methods for EC in various food matrices have been established. Due to the potential threat of EC to human health, mitigation strategies for EC in food products by physical, chemical, enzymatic, and genetic engineering methods have been developed...
May 15, 2018: Food Chemistry
https://www.readbyqxmd.com/read/29329425/comparison-of-hepatic-2d-sandwich-cultures-and-3d-spheroids-for-long-term-toxicity-applications-a-multi-center-study
#14
Catherine C Bell, Anita C A Dankers, Volker M Lauschke, Rowena Sison-Young, Roz Jenkins, Cliff Rowe, Chris Goldring, Kevin Park, Sophie Regan, Tracy Walker, Chris Schofield, Audrey Baze, Alison J Foster, Dominic Williams, Amy W M van de Ven, Frank Jacobs, Jos van Houdt, Tuula Lähteenmäki, Jan Snoeys, Satu Juhila, Lysiane Richert, Magnus Ingelman-Sundberg
Primary human hepatocytes (PHH) are commonly used for in vitro studies of drug-induced liver injury. However, when cultured as 2D monolayers, PHH lose crucial hepatic functions within hours. This dedifferentiation can be ameliorated when PHH are cultured in sandwich configuration (2Dsw), particularly when cultures are regularly re-overlaid with extracellular matrix, or as 3D spheroids. In this study, the six participating laboratories evaluated the robustness of these two model systems made from cryopreserved PHH from the same donors considering both inter-donor and inter-lab variability and compared their suitability for use in repeated-dose toxicity studies using 5 different hepatotoxins with different toxicity mechanisms...
January 10, 2018: Toxicological Sciences: An Official Journal of the Society of Toxicology
https://www.readbyqxmd.com/read/29329270/toxicity-evaluation-of-individual-and-mixtures-of-nanoparticles-based-on-algal-chlorophyll-content-and-cell-count
#15
Kyung-Seok Ko, Dong-Chan Koh, In Chul Kong
The toxic effects of individual and binary mixtures of five metal oxide nanoparticles (NPs) were evaluated based on changes in two endpoints of algal growth: the cell count and chlorophyll content. Various effects were observed according to the concentration tested and type of NPs, and there were no significant differences in findings for the two endpoints. In general, ZnO NPs caused the greatest inhibition of algal growth, and Fe₂O₃ NPs the least. The EC50 for ZnO was 2.0 mg/L for the cell count and 2...
January 12, 2018: Materials
https://www.readbyqxmd.com/read/29329085/an-integrated-approach-to-assess-the-impacts-of-zinc-pyrithione-at-different-levels-of-biological-organization-in-marine-mussels
#16
Lorna J Dallas, Andrew Turner, Tim P Bean, Brett P Lyons, Awadhesh N Jha
The mechanisms of sublethal toxicity of the antifouling biocide, zinc pyrithione (ZnPT), have not been well-studied. This investigation demonstrates that 14-d sublethal exposure to ZnPT (0.2 or 2 μM, alongside inorganic Zn and sea water controls) is genotoxic to mussel haemocytes but suggests that this is not caused by oxidative DNA damage as no significant induction of oxidised purines was detected by Fpg-modified comet assay. More ecologically relevant endpoints, including decreased clearance rate (CR), cessation of attachment and decreased tolerance of stress on stress (SoS), also showed significant response to ZnPT exposure...
December 27, 2017: Chemosphere
https://www.readbyqxmd.com/read/29329084/sources-of-polychlorinated-dibenzo-p-dioxins-and-dibenzofurans-and-biphenyls-in-chinese-mitten-crabs
#17
Ying Han, Wenbin Liu, Wen Zhu, Kaifeng Rao, Ke Xiao, Lirong Gao, Guijin Su, Guorui Liu
Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polychlorinated biphenyls (PCBs) in Chinese mitten crabs from several areas were determined. The toxic equivalents (TEQs) for the mean PCDD/F and total PCDD/F and dioxin-like PCBs were 2.9 ± 2.7 and 5.7 ± 4.0 pg TEQ g-1, respectively. The mean concentrations of PCBs and dl-PCBs were 282 and 59 times the concentrations of PCDD/Fs, respectively. PCDD/F and PCB sources in the crab food web were assessed. The total TEQ of PCDD/F and PCB supplied by crab compound feed was 2...
January 6, 2018: Chemosphere
https://www.readbyqxmd.com/read/29328974/novel-approach-for-evaluating-pharmaceuticals-toxicity-using-daphnia-model-analysis-of-the-mode-of-cytochrome-p450-generated-metabolite-action-after-acetaminophen-exposure
#18
Ryeo-Ok Kim, Min-A Jo, Jinhaeng Song, Il-Chan Kim, Seokjoo Yoon, Woo-Keun Kim
Because of its widespread use, the pharmaceutical acetaminophen (APAP) is frequently detected in aquatic environments. APAP can have serious physiological effects, such as reduced reproduction, low growth rates, and abnormal behavior, in aquatic organisms. However, the methods available for evaluation of the aquatic toxicity of APAP are of limited usefulness. The present study aimed to develop reliable and sensitive markers for evaluation of APAP toxicity using Daphnia as a model organism. We focused on N-acetyl-p-benzoquinoneimine (NAPQI) production from APAP via cytochrome P450 metabolism because NAPQI causes APAP toxicity...
December 30, 2017: Aquatic Toxicology
https://www.readbyqxmd.com/read/29328973/feeding-inhibition-in-corbicula-fluminea-o-f-muller-1774-as-an-effect-criterion-to-pollutant-exposure-perspectives-for-ecotoxicity-screening-and-refinement-of-chemical-control
#19
Bruno Branco Castro, Carlos Silva, Inês Patrunilho Efe Macário, Bruno Oliveira, Fernando Gonçalves, Joana Luísa Pereira
Bivalves are commonly used in biomonitoring programs to track pollutants. Several features, including its filter-feeding abilities, cumulatively argue in favour of the use of the Asian clam (Corbicula fluminea) as a biosentinel and an ecotoxicological model. Filtration in bivalves is very sensitive to external stimuli and its control is dictated by regulation of the opening/closure of the valves, which may be used as an avoidance defence against contaminants. Here, we investigate the filter-feeding behaviour of the Asian clam as an endpoint for assessing exposure to pollutants, driven by two complementary goals: (i) to generate relevant and sensitive toxicological information based on the ability of C...
January 4, 2018: Aquatic Toxicology
https://www.readbyqxmd.com/read/29328451/a-systematic-review-and-meta-analysis-of-bidirectional-effect-of-arsenic-on-erk-signaling-pathway
#20
Dongjie Li, Yutao Wei, Shangzhi Xu, Qiang Niu, Mei Zhang, Shugang Li, Mingxia Jing
Arsenic is a toxic metal, which ultimately leads to cell apoptosis. ERK is considered a key transcriptional regulator of arsenic‑induced apoptosis. Due to a few controversial issues about arsenic‑mediated extracellular signal‑regulated MAP kinases (ERK) signaling, a meta‑analysis was performed. Subgroup analyses demonstrated that high doses (≥2 µmol/l) of arsenic increased the expression of Ras, ERK, ERK1, ERK2, phosphorylated (p)‑ERK, p‑ERK1, and p‑ERK2, while low doses (<2 µmol/l) decreased the expression of Ras, ERK1, p‑ERK, and p‑ERK2 when compared to control groups...
January 5, 2018: Molecular Medicine Reports
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