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T‐2 toxin is the most toxic among mycotoxins and poses a potential health hazard for both humans and animals. At high doses, T‐2 toxin can cause shock‐like syndrome that can result in death. We evaluated the effect of time course and route of exposure on hepatic oxidative damage in mice and it is only such study so far to compare the effects of dermal and subcutaneous exposure of T‐2 toxin. Mice were exposed to 1 LD50 of T‐2 toxin either by percutaneous (5.94 mg/kg body weight) or subcutaneous (1.54 mg/kg body weight) route and sacrificed at 0, 1, 3, and 7 days postexposure. Analysis of a number of serum biochemical variables, antioxidant enzymes activity, gene and protein expression by immunoblot assay showed time and route dependent effects of T‐2 induced hepatic oxidative damage. Time dependent increase in protein carbonyl content and protein oxidation was seen in serum and liver. Results of our study may provide possible mechanism for developing medical countermeasures against T‐2 toxin. © 2013 Wiley Periodicals, Inc. Environ Toxicol 30: 64–73, 2015.  相似文献   
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Invasive fungal infections (IFI) are associated with significant health burden in preterm neonates. The objective of this study was to systematically review effect of probiotic supplementation (PS) for preventing IFI in preterm neonates. We searched Cochrane Central Register of Controlled Trials, Medline, Embase, Cumulative Index of Nursing and Allied Health Literature, and proceedings of the Pediatric Academic Society meetings in August 2014. Study selection was performed on randomised controlled trials ( RCT) of PS in neonates born <37 weeks. Primary outcome of this study was IFI (Isolation of fungus in blood/body fluids) and secondary outcome was fungal gut colonisation. Information on IFI/colonisation was available in 8 of 27 RCT. Meta‐analysis (fixed effects model) showed that PS reduced the risk of IFI (RR: 0.50, 95% CI: 0.34, 0.73, I2 = 39%). Results were not significant with random effects model (RR: 0.64, 95%, CI: 0.30, 1.38, P = 0.25, I2 = 39%). Analysis after excluding the study with a high baseline incidence (75%) of IFI showed that PS had no significant benefits (RR: 0.89; 95% CI: 0.44, 1.78). Of the five studies reporting on fungal gut colonisation, three reported benefits of probiotics; two did not. Current evidence is limited to derive firm conclusions on the effect of PS for preventing IFI/gut colonisation in preterm neonates.  相似文献   
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Depression is a major psychiatric illness that is associated with cognitive dysfunctions. The underlying mechanism of depression‐associated memory impairment is unclear. Previously, we showed altered hippocampal synaptic plasticity in an animal model of depression. Although several antidepressants are beneficial in the treatment of depression, very little is known about the effects of these drugs on depression‐associated learning and memory deficits. Prolonged antidepressant treatment might contribute to neuroplastic changes required for clinical outcomes. Accordingly, we evaluated the effect of chronic reboxetine (a selective noradrenergic reuptake inhibitor) treatment on depression‐induced reduced hippocampal synaptic plasticity, neurotransmitter levels, and spatial learning and memory impairments. Depression was induced in male Wistar rats by the administration of clomipramine from postnatal days 8 to 21, and these rats were treated with reboxetine in adulthood. The neonatal clomipramine administration resulted in impaired hippocampal long‐term potentiation (LTP), decreased hippocampal cholinergic activity and monoamine levels, and poor performance in a partially baited eight‐arm radial maze task. Chronic reboxetine treatment restored the hippocampal LTP, acetylcholinesterase activity, and levels of biogenic amines and ameliorated spatial learning and memory deficits in the depressed state. Thus, restoration of hippocampal synaptic plasticity might be a cellular mechanism underlying the beneficial effect of reboxetine in depression‐associated cognitive deficits. This study furthers the existing understanding of the effects of antidepressants on learning, memory, and synaptic plasticity and could ultimately assist in the development of better therapeutic strategies to treat depression and associated cognitive impairments. © 2014 Wiley Periodicals, Inc.  相似文献   
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Aluminium oxide nanoparticles (Al2O3 NPs) are increasingly used in diverse applications that has raised concern about their safety. Recent studies suggested that Al2O3 NPs induced oxidative stress may be the cause of toxicity in algae, Ceriodaphnia dubia, Caenorhabditis elegans and Danio rerio. However, there is paucity on the toxicity of Al2O3 NPs on fish cell lines. The current study was aimed to investigate Al2O3 NPs induced cytotoxicity, oxidative stress and morphological abnormality of Chinnok salmon cells (CHSE‐214). A dose‐dependent decline in cell viability was observed in CHSE‐214 cells exposed to Al2O3 NPs. Oxidative stress induced by Al2O3 NPs in CHSE‐214 cells has resulted in the significant reduction of superoxide dismutase, catalase and glutathione in a dose‐dependent manner. However, a significant increase in glutathione sulfo‐transferase and lipid peroxidation was observed in CHSE‐214 cells exposed to Al2O3 NPs in a dose‐dependent manner. Significant morphological changes in CHSE‐214 cells were observed when exposed to Al2O3 NPs at 6, 12 and 24 h. The cells started to detach and appear spherical at 6 h followed by loss of cellular contents resulting in the shrinking of the cells. At 24 h, the cells started to disintegrate and resulted in cell death. Our data demonstrate that Al2O3 NPs induce cytotoxicity and oxidative stress in a dose‐dependent manner in CHSE‐214 cells. Thus, our current work may serve as a base‐line study for future evaluation of toxicity studies using CHSE‐214 cells. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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