Toxicology Research Today is a free monthly online journal that collates and summarizes the latest research about Toxicology, including details on forensic toxicology, carcinogenicity, assays. | ||||||
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Embryotoxicity of weathered crude oil from the gulf of Mexico in mallard ducks (Anas platyrhynchos).Finch BE, Wooten KJ, Smith PN The Institute of Environmental and Human Health, Department of Environmental Toxicology, Texas Tech University, Lubbock, Texas USA. Weathered crude oil in the Gulf of Mexico can result from oil spills such as the Deepwater Horizon incident that occurred on April 20, 2010 or from natural seeps. Adult waterbirds of the Gulf Coast region may become exposed to weathered crude oil while foraging, wading, or resting, and residues can then be transferred to nests, eggs, and hatchlings. Although the toxicity of many types of crude oil to avian embryos has been thoroughly studied, the effects of weathered crude oil on developing avian embryos are not well characterized. The objective of the present study was to examine embryotoxicity of weathered crude oil collected from the Gulf of Mexico in June 2010 using mallard ducks (Anas platyrhynchos) as a model species. Weathered crude oil was applied to fertilized mallard duck eggs by paintbrush in masses ranging from 0.1 to 99.9 mg on day 3 of incubation. Mortality occurred as early as day 7 and the median lethal application of weathered crude oil was 30.8 mg/egg (0.5 mg/g egg) or 30.7 µl/egg (0.5 µl/g egg). Body mass, liver and spleen mass, crown rump and bill lengths, and frequency of deformities were not significantly different among hatchlings from oiled and control eggs. In comparison to published reports of fresh crude oil embryotoxicity, weathered crude oil was considerably less toxic. We conclude that avian toxicity varies according to the degree of crude oil weathering and the stage of embryonic development at the time of exposure. Results indicate bird eggs exposed to weathered crude oil from the Gulf of Mexico during summer 2010 may have had reduced hatching success. Environ. Toxicol. Chem. © 2011 SETAC. Published 11 May 2011 in Environ Toxicol Chem. Articles on Toxicology published 11 May 2011: ∆(9)-Tetrahydrocannabinol-dependent mice undergoing withdrawal display impaired spatial memory. Psychopharmacology (Berl). RATIONALE: Cannabis users display a constellation of withdrawal symptoms upon drug discontinuation, including sleep disturbances, irritability, and possibly memory deficits. In cannabinoid-dependent rodents, the CB(1) antagonist rimonabant precipitates somatic withdrawal and enhances forskolin-stimulated adenylyl cyclase activity in cerebellum, an effect opposite that of acutely administered ∆(9)-tetrahydrocannabinol (THC), the primary constituent in cannabis. OBJECTIVES: Here, we tested ... [Abstract] [Full-text] PPARγ dependence of cyclosporine-isoprenaline renovascular interaction: Roles of nitric oxide synthase and heme oxygenase. J Cardiovasc Pharmacol. We previously showed that cyclosporine (CSA) impairs renal vasodilations caused by β-adrenoceptor activation. This study investigated whether the peroxisome proliferator-activated receptor-gamma (PPARγ) and related nitric oxide synthase (NOS)/heme oxygenase (HO) signaling mediates the CSA-β-adrenoceptor interaction. The vasodilatory response elicited by bolus injection of isoprenaline (1 μmol) in phenylephrine-preconstricted perfused kidneys of rats was reduced after prior infusion of zinc ... [Abstract] [Full-text] Connective Tissue Growth Factor Acts as a Therapeutic Agent and Predictor for Peritoneal Carcinomatosis of Colorectal Cancer. Clin Cancer Res. PURPOSE: Here, we aimed to investigate the role of connective tissue growth factor (CTGF) in peritoneal carcinomatosis (PC) associated with colorectal cancer (CRC) and to characterize the underlying mechanism of CTGF mediating adhesion. EXPERIMENTAL DESIGN: A cohort of 136 CRC patient specimens was analyzed in this study. CRC cell lines were used for in vitro adhesion assay and in vivo peritoneal dissemination experiment. Recombinant CTGF protein treatment, transfection of CTGF expression ... [Abstract] [Full-text] Hormesis, resveratrol and plant-derived polyphenols: some comments. Hum Exp Toxicol. Hormesis is a dose-response phenomenon, usually present in plants and animals, characterized by a low-dose stimulation and high-dose inhibition, often resulting in typical U-shaped or J-shaped curves. Hormesis has become an interesting model for toxicology and risk assessment, as it has been described for several nature-derived phytochemicals but also because this adaptive response to stressors might hide an underlying more general behaviour of cell towards low doses. [Abstract] [Full-text] Influence of N-acetylcysteine against dimethylnitrosamine induced hepatotoxicity in rats. Toxicol Ind Health. This study evaluates the hepatoprotective and antioxidant properties of N-acetylcysteine (NAC) on dimethylnitrosamine (DMN) induced hepatotoxicity in male Wistar albino rats. A single intraperitoneal dose of DMN (5 mg/kg b.w.) caused a significant increase in the levels of the serum marker enzymes (aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), glutamyl transpeptidase (γ-GT)) and a subsequent decrease in AST, ALT, ALP and ... [Abstract] [Full-text] Fenvalerate, a type II synthetic pyrethroid, has emerged as one of the most potent indoor toxicants. Despite its widespread usage, the adverse effect of this insecticide on immune defense mechanism has not been comprehensively investigated. In this in vitro study we report the effect of fenvalerate on two pivotal components of the immune network, namely the complement system and macrophages. Fenvalerate treated human sera showed serum complement activation as evident by significant (p<0.05) ... [Abstract] [Full-text] Depletion and recovery of lymphoid subsets following morphine administration. Br J Pharmacol. Background and purpose: Opioid use and abuse has been linked to significant immunosuppression, which has been attributed, in part, to drug-induced depletion of lymphocytes. We sought to define the mechanisms by which lymphocyte populations are depleted and recover following morphine treatment in mice. Experimental approach: Mice were implanted with morphine pellets and B and T cell subsets in the bone marrow, thymus, spleen, and lymph nodes were analyzed at various time points. We also examined ... [Abstract] [Full-text] Allosteric Modulation of Glycine Receptors. Br J Pharmacol. Inhibitory (or strychnine-sensitive) glycine receptors (GlyRs) are anion-selective transmitter-gated ion channels of the cys-loop superfamily, which includes among others also the inhibitory γ-aminobutyric acid receptors (GABA(A) receptors). While GABA mediates fast inhibitory neurotransmission throughout the CNS, the action of glycine as a fast inhibitory neurotransmitter is more restricted. This probably explains why GABA(A) receptors constitute a group of extremely successful drug targets ... [Abstract] [Full-text] © 2005-2011 Toxicology Research Today. All Rights Reserved. |
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