Advances in Toxicology The latest articles from Hindawi Publishing Corporation © 2014 , Hindawi Publishing Corporation . All rights reserved. Differential Effect of Isooctane Doses on HaCaT and HeLa: A Multimodal Analysis Thu, 09 Oct 2014 10:12:11 +0000 A multimodal approach is effective in analyzing biological problems critically and thus also useful in assessing cytotoxicity under chemicals assaults. In this study effects of isooctane, an organic solvent and component of gasoline produced in petroleum industries, have been explored on normal (HaCaT) and cancerous (HeLa) epithelial cells. Besides morphological alterations, impacts on viability, prime molecular expressions, and bioelectrical properties on exposure to different doses of isooctane were noted. Scanning electron microscopy and viability assay demonstrated remarkable structural alterations and cell death, respectively, in HaCaT but not in HeLa. Transcriptomic and immunocytochemical studies on E-cadherin expression also elucidated pronounced toxic effects on HaCaT. Remarkable changes on the bioelectrical properties (e.g., impedance and phase angle) of the HaCaT, in contrast to HeLa, at different temporal points on isooctane exposure also indicated cytotoxic effects in the former. Hence this study illustrated cytotoxicity of isooctane on HaCaT multidimensionally which was evaded by HeLa. Lopamudra Das, Sanmitra Basu, Sanghamitra Sengupta, Soumen Das, and Jyotirmoy Chatterjee Copyright © 2014 Lopamudra Das et al. All rights reserved. Dual Role of Hydrogen Peroxide in Arabidopsis Guard Cells in Response to Sulfur Dioxide Tue, 30 Sep 2014 12:55:55 +0000 Sulfur dioxide (SO2) is a major air pollutant and has significant impacts on plant physiology. Plant can adapt to SO2 stress by controlling stomatal movement, gene expression, and metabolic changes. Here we show clear evidences that SO2-triggered hydrogen peroxide (H2O2) production mediated stomatal closure and cell death in Arabidopsis leaves. High levels of SO2 caused irreversible stomatal closure and decline in guard cell viability, but low levels of SO2 caused reversible stomatal closure. Exogenous antioxidants ascorbic acid (AsA) and catalase (CAT) or Ca2+ antagonists EGTA and LaCl3 blocked SO2-induced stomatal closure and decline in viability. AsA and CAT also blocked SO2-induced H2O2 and elevation. However, EGTA and LaCl3 inhibited SO2-induced increase but did not suppress SO2-induced H2O2 elevation. These results indicate that H2O2 elevation triggered stomatal closure and cell death via signaling in SO2-stimulated Arabidopsis guard cells. NADPH oxidase inhibitor DPI blocked SO2-induced cell death but not the stomatal closure triggered by low levels of SO2, indicating that NADPH oxidase-dependent H2O2 production plays critical role in SO2 toxicity but is not necessary for SO2-induced stomatal closure. Our results suggest that H2O2 production and accumulation in SO2-stimulated plants trigger plant adaptation and toxicity via reactive oxygen species mediating Ca2+ signaling. Huilan Yi, Xin Liu, Min Yi, and Gang Chen Copyright © 2014 Huilan Yi et al. All rights reserved. Compound-Specific Toxicities Detected in CFU-GM, Rat Kidney NRK Cells, Rat Bladder RBLAK Cells, and Rat Liver Slices following Batracylin or N-Acetyl Batracylin Exposure Mon, 08 Sep 2014 00:00:00 +0000 The investigational anticancer agent batracylin (BAT; 8-aminoisoindolo [1,2-b]quinazolin-10(12H)-one; NSC320846) causes γ-H2AX foci development in exposed tumor cells and has demonstrated activity against solid tumors and adriamycin-resistant leukemia. Reports indicate BAT has wide interspecies variation of adverse effects, including myelosuppression, kidney, bladder, and liver damage, including biliary hyperplasia. The effects of BAT and its metabolite N-acetyl batracylin (NAB) were evaluated in the CFU-GM bone marrow toxicity assay, rat kidney (NRK) cells, bladder epithelial (RBLAK) cells, and rat precision cut liver slices (PCLS). Exposure effects were evaluated biochemically and histologically. Human, dog, and rat exhibited similar CFU-GM IC90 values for BAT (21–29 μM). The ATP assay and γ-H2AX staining showed time- and concentration-dependent toxicity in RBLAK (more severe than NRK at <72 hr) NRK and cells ( μM after 96 hr BAT exposure). BAT (5 μM and 25 μM) caused biochemical and histology changes to PCLS by day 3 and 25 μM produced centrilobular hepatotoxicity. NAB (≤5 μM) produced no toxicity in CFU-GM, NRK, or RBLAK cells. However, both BAT and NAB caused biliary epithelial cell proliferation in PCLS. Our studies demonstrated species similarities in sensitivity to BAT-induced myelosuppression, and implicate the metabolite NAB in biliary hyperplasia. Facundo M. Cutuli and Holger P. Behrsing Copyright © 2014 Facundo M. Cutuli and Holger P. Behrsing. All rights reserved. Extraction of Parquat from Blood by Clinoptilolite Tue, 19 Aug 2014 06:38:48 +0000 Paraquat is a bipyridyl herbicide and organic divalent cation which due to its high polarity and water solubility cannot be readily extracted by common organic solvents from body fluids. Dithionite color test for qualitative and quantitative determination of paraquat in urine has been proposed and used for many years. Although some methods were proposed for solvent extraction of paraquat from blood, they are less practical in clinical laboratories and lack high extraction recovery. Clinoptilolite is a highly porous natural zeolite with cation-exchange property and high surface area. In the present work, extraction of paraquat from human blood by clinoptilolite was investigated and compared with Amberlite CG-50 I, a well-known weak cation-exchanger. Blood paraquat was adsorbed by adsorbents (clinoptilolite or Amberlite) and extracted from them by saturated sodium chloride solution. Extracted paraquat was spectrophotometrically measured by means of sodium dithionite reagent at 394.5 nm. Recovery, limit of detection, considering signal-to-noise (S/N) ratio of 3, and limit of quantification, regarding S/N of 10, of paraquat extraction by clinoptilolite and Amberlite CG-50 were 81.7% ± 3.4%, 0.58 μg, and 1.93 μg and 83.6% ± 3.2%, 0.49 μg, and 1.63 μg, respectively. Repeatabilities (within-laboratory error) of paraquat extraction by clinoptilolite and Amberlite CG-50 I were 7.1% and 6.3%, respectively. Mohammad-Amin Aghaii-Afshar and Seyed Vahid Shetab-Boushehri Copyright © 2014 Mohammad-Amin Aghaii-Afshar and Seyed Vahid Shetab-Boushehri. All rights reserved.