Toxicokinetics and toxicodynamics of chlorpyrifos is altered in embryos of Japanese medaka exposed to oil sands process-affected water: evidence for inhibition of P-glycoprotein.

Oil sands process-affected water (OSPW) is generated during extraction of bitumen in the surface mining oil sands industry in Alberta, Canada. Studies were performed in vitro by use of Caco-2 cells, and in vivo with larvae of Japanese medaka (Oryzias latipes) to determine if organic compounds from the aqueous phase of OSPW inhibit ATP binding cassette protein ABCB1 (permeability-glycoprotein, P-gp). Neutral and basic fractions of OSPW inhibited activity of P-gp in Caco-2 cells by 1.

Identification of Thyroid Hormone Disruptors among HO-PBDEs: In Vitro Investigations and Coregulator Involved Simulations.

Some hydroxylated polybrominated diphenyl ethers (HO-PBDEs), that have been widely detected in the environment and tissues of humans and wildlife, bind to thyroid hormone (TH) receptor (TR) and can disrupt functioning of systems modulated by the TR. However, mechanisms of TH disrupting effects are still equivocal. Here, disruption of functions of TH modulated pathways by HO-PBDEs was evaluated by assays of competitive binding, coactivator recruitment, and proliferation of GH3 cells.

Glucuronide and sulfate conjugates of tetrabromobisphenol A (TBBPA): Chemical synthesis and correlation between their urinary levels and plasma TBBPA content in voluntary human donors.

3,3',5,5'-Tetrabromobisphenol-A (TBBPA) is an important brominated flame retardant in epoxy, vinyl esters and polycarbonate resins. Previous studies have already shown the occurrence of its Phase II metabolites, TBBPA-glucuronide and sulfate conjugates, in human urine, after oral administration of TBBPA. The main objective of this work is to examine correlations among level of TBBPA in human blood and those of its Phase II metabolites in human urine.

Calcium-Sensing Receptor and Transient Receptor Ankyrin-1 Mediate Emesis Induction by Deoxynivalenol (Vomitoxin).

The common foodborne mycotoxin deoxynivalenol (DON, vomitoxin) can negatively impact animal and human health by causing food refusal and vomiting. Gut enteroendocrine cells (EECs) secrete hormones that mediate DON's anorectic and emetic effects. In prior work utilizing a cloned EEC model, our laboratory discovered that DON-induced activation of calcium-sensing receptor (CaSR), a G-coupled protein receptor (GPCR), and transient receptor ankyrin-1 (TRPA1), a transient receptor potential (TRP) channel, drives Ca-mediated hormone secretion.

Effects of captivity and artificial breeding on microbiota in feces of the red-crowned crane (Grus japonensis).

Reintroduction of the threatened red-crowned crane has been unsuccessful. Although gut microbiota correlates with host health, there is little information on gut microbiota of cranes under different conservation strategies. The study examined effects of captivity, artificial breeding and life stage on gut microbiota of red-crown cranes.

Untargeted Screening and Distribution of Organo-Iodine Compounds in Sediments from Lake Michigan and the Arctic Ocean.

The majority of halogenated organic compounds present in the environment remain unidentified. To address this data gap, we recently developed an untargeted method (data-independent precursor isolation and characteristic fragment; DIPIC-Frag) for identification of unknown organo-bromine compounds. In this study, the method was adapted to enable untargeted screening of natural and synthetic organo-iodine compounds (NSOICs) in sediments.

Impairment of reproduction of adult zebrafish (Danio rerio) by binary mixtures of environmentally relevant concentrations of triclocarban and inorganic mercury.

Effects of chemical mixtures at environmentally relevant concentrations on endocrine systems of aquatic organisms are of concern. Triclocarban (TCC) and inorganic mercury (Hg) are ubiquitous in aquatic environments, and are known to interfere with endocrine pathways via different mechanisms of toxic action. However, effects of mixtures of the two pollutants on aquatic organisms and associated molecular mechanisms were unknown.

Linking Oxidative Stress and Magnitude of Compensatory Responses with Life-Stage Specific Differences in Sensitivity of White Sturgeon (Acipenser transmontanus) to Copper or Cadmium.

Sensitivity of white sturgeon (Acipenser transmontanus) to copper (Cu) or cadmium (Cd) has been shown to significantly differ as a function of life-stage. This study investigated oxidative stress, metal homeostasis, and associated compensatory responses as potential mechanisms of this sensitivity pattern in three early life-stages. Sturgeon were most sensitive to Cu at 15 days post hatch (dph), which was accompanied by a significant increase in lipid peroxidation (LPO).

Effect of Lipid Partitioning on Predictions of Acute Toxicity of Oil Sands Process Affected Water to Embryos of Fathead Minnow (Pimephales promelas).

Dissolved organic compounds in oil sands process affected water (OSPW) are known to be responsible for most of its toxicity to aquatic organisms, but the complexity of this mixture prevents use of traditional bottom-up approaches for predicting toxicities of mixtures. Therefore, a top-down approach to predict toxicity of the dissolved organic fraction of OSPW was developed and tested. Accurate masses (i.

Peroxisome Proliferator-Activated Receptor γ is a Sensitive Target for Oil Sands Process-Affected Water: Effects on Adipogenesis and Identification of Ligands.

Identification of toxic components of complex mixtures is a challenge. Here, oil sands process-affected water (OSPW) was used as a case study to identify those toxic components with a known protein target. Organic chemicals in OSPW exhibited dose-dependent activation of peroxisome proliferator-activated receptor γ (PPARγ) at concentrations less than those currently in the environment (0.

Combined Transcriptomic and Proteomic Approach to Identify Toxicity Pathways in Early Life Stages of Japanese Medaka (Oryzias latipes) Exposed to 1,2,5,6-Tetrabromocyclooctane (TBCO).

Currently, the novel brominated flame retardant 1,2,5,6-tetrabromocyclooctane (TBCO) is considered a potential replacement for hexabromocyclododecane (HBCD). Therefore, use of TBCO could increase in the near future. To assess potential toxicological risks to aquatic organisms, embryos of Japanese medaka (Oryzias latipes) were exposed to 10, 100, or 1000 μg/L TBCO from 2 h postfertilization until 1 day post-hatch.

Reduced Noradrenergic Signaling in the Spleen Capsule in the Absence of CB and CB Cannabinoid Receptors.

The spleen is a visceral organ that contracts during hypoxia to expel erythrocytes and immune cells into the circulation. Spleen contraction is under the control of noradrenergic sympathetic innervation. The activity of noradrenergic neurons terminating in the spleen capsule is regulated by α2-adrenergic receptors (AR).

Effects of Zinc Chelators on Aflatoxin Production in Aspergillus parasiticus.

Zinc concentrations strongly influence aflatoxin accumulation in laboratory media and in food and feed crops. The presence of zinc stimulates aflatoxin production, and the absence of zinc impedes toxin production. Initial studies that suggested a link between zinc and aflatoxin biosynthesis were presented in the 1970s.

Bioconcentration of Dissolved Organic Compounds from Oil Sands Process-Affected Water by Medaka (Oryzias latipes): Importance of Partitioning to Phospholipids.

The complex mixture of dissolved organics in oil sands process-affected water (OSPW) is acutely lethal to fish at environmentally relevant concentrations, but few bioconcentration factors (BCFs) have been measured for its many chemical species. Japanese medaka (Oryzias latipes) were exposed to 10% OSPW, and measured BCFs were evaluated against predicted BCFs from octanol-water distribution ratios (DOW) and phospholipid membrane-water distribution ratios (DMW). Two heteroatomic chemical classes detected in positive ion mode (SO(+), NO(+)) and one in negative mode (O2(-), also known as naphthenic acids) had the greatest DMW values, as high as 10 000.

CRACC-targeting Fc-fusion protein induces activation of NK cells and DCs and improves T cell immune responses to antigenic targets.

The CD2-like receptor activating cytotoxic cell (CRACC) receptor is a member of the SLAM family of receptors that are found on several types of immune cells. We previously demonstrated that increasing the abundance of the adaptor protein EAT-2 during vaccination enhanced innate and adaptive immune responses to vaccine antigens. Engagement of the CRACC receptor in the presence of the EAT-2 adaptor generally results in immune cell activation, while activating CRACC signaling in cells that lack EAT-2 adaptor inhibits their effector and regulatory functions.

Effect of oil sands process-affected water on toxicity of retene to early life-stages of Japanese medaka (Oryzias latipes).

Toxicity of oil sands process-affected water (OSPW) to aquatic organisms has been studied, but effects of co-exposure to OSPW and polycyclic-aromatic hydrocarbons (PAHs), which are an important class of chemicals in tailings ponds used to store OSPW, has not been investigated. The goal of the current study was to determine if organic compounds extracted from the aqueous phase of relatively fresh OSPW from Base-Mine Lake (BML-OSPW) or aged OSPW from Pond 9 experimental reclamation pond (P9-OSPW) modulated toxic potency of the model alkyl-PAH, retene, to early life-stages of Japanese medaka (Oryzias latipes). Embryos were exposed to retene by use of a partition controlled delivery (PCD) system made of polydimethylsiloxane (PDMS) until day of hatch.

Are styrene oligomers in coastal sediments of an industrial area aryl hydrocarbon-receptor agonists?

Effect-directed analysis (EDA) was performed to identify the major aryl hydrocarbon receptor (AhR) agonists in sediments collected from a highly industrialized area (Lake Shihwa, Korea). Great AhR-mediated potencies were found in fractions containing aromatic compounds with log Kow values of 5-8, and relatively great concentrations of styrene oligomers (SOs) and polycyclic aromatic hydrocarbons (PAHs) were detected in those fractions. Until now, there was little information on occurrences and toxic relative potencies (RePs) of SOs in coastal environments.

Potential roles for calcium-sensing receptor (CaSR) and transient receptor potential ankyrin-1 (TRPA1) in murine anorectic response to deoxynivalenol (vomitoxin).

Food contamination by the trichothecene mycotoxin deoxynivalenol (DON, vomitoxin) has the potential to adversely affect animal and human health by suppressing food intake and impairing growth. In mice, the DON-induced anorectic response results from aberrant satiety hormone secretion by enteroendocrine cells (EECs) of the gastrointestinal tract. Recent in vitro studies in the murine STC-1 EEC model have linked DON-induced satiety hormone secretion to activation of calcium-sensing receptor (CaSR), a G-coupled protein receptor, and transient receptor potential ankyrin-1 (TRPA1), a TRP channel.

Characterization of organic matter of plants from lakes by thermal analysis in a N2 atmosphere.

Organic matter (OM) has been characterized using thermal analysis in O2 atmospheres, but it is not clear if OM can be characterized using slow thermal degradation in N2 atmospheres (STDN). This article presents a new method to estimate the behavior of OM in anaerobic environment. Seventeen different plants from Tai Lake (Ch: Taihu), China were heated to 600 °C at a rate of 10 °C min(-1) in a N2 atmosphere and characterized by use of differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA).

Directly Predicting Water Quality Criteria from Physicochemical Properties of Transition Metals.

Transition metals are a group of elements widespread in aquatic environments that can be hazardous when concentrations exceeding threshold values. Due to insufficient data, criteria maximum concentrations (CMCs) of only seven transition metals for protecting aquatic life have been recommended by the USEPA. Hence, it is deemed necessary to develop empirical models for predicting the threshold values of water quality criteria (WQC) for other transition metals for which insufficient information on toxic potency is available.

Identification of a long non-coding RNA NR_026689 associated with lung carcinogenesis induced by NNK.

Long non-coding RNAs (lncRNA) are thought to be important epigenetic regulators involved in the development of a variety of cancers. Alterations in lncRNA expression are associated with exposure to chemical carcinogens. However, it is still unclear whether lncRNA expression during lung carcinogenesis is induced by chemical carcinogens.

Sunlight Irradiation of Highly Brominated Polyphenyl Ethers Generates Polybenzofuran Products That Alter Dioxin-responsive mRNA Expression in Chicken Hepatocytes.

We report on two highly brominated polyphenyl ether flame retardants, tetradecabromo-1,4- diphenoxybenzene (TeDB-DiPhOBz) and 2,2',3,3',4,4',5,5',6,6'-decabromodiphenyl ether (BDE-209), that formed photolytic degradation products in tetrahydrofuran (THF)/hexane solvent after 21 days of natural sunlight irradiation (SI). These degradation products of SI-TeDB-DiPhOBz and SI-BDE-209 included the numerous polybrominated homologue groups of polybenzofurans and dibenzofurans, respectively. Formation of similar polybenzofuran and dibenzofuran products was also observed following a 3 month exposure of the solid powder forms of TeDB-DiPhOBz and BDE-209 to natural SI.

Inhibition of ABC transport proteins by oil sands process affected water.

The ATP-binding cassette (ABC) superfamily of transporter proteins is important for detoxification of xenobiotics. For example, ABC transporters from the multidrug-resistance protein (MRP) subfamily are important for excretion of polycyclic aromatic hydrocarbons (PAHs) and their metabolites. Effects of chemicals in the water soluble organic fraction of relatively fresh oil sands process affected water (OSPW) from Base Mine Lake (BML-OSPW) and aged OSPW from Pond 9 (P9-OSPW) on the activity of MRP transporters were investigated in vivo by use of Japanese medaka at the fry stage of development.

Untargeted Screening and Distribution of Organo-Bromine Compounds in Sediments of Lake Michigan.

Previously unreported natural and synthetic organo-bromine compounds (NSOBCs) have been found to contribute more than 99% of total organic bromine (TOB) in environmental matrices. We recently developed a novel untargeted method (data-independent precursor isolation and characteristic fragment, DIPIC-Frag) and identified ∼2000 NSOBCs in two sediments from Lake Michigan. In this study, this method was used to investigate the distributions of these NSOBCs in 23 surficial samples and 24 segments of a sediment core from Lake Michigan.

Concentrations of neonicotinoid insecticides in honey, pollen and honey bees (Apis mellifera L.) in central Saskatchewan, Canada.

Neonicotinoid insecticides (NIs) and their transformation products were detected in honey, pollen and honey bees, (Apis mellifera) from hives located within 30 km of the City of Saskatoon, Saskatchewan, Canada. Clothianidin and thiamethoxam were the most frequently detected NIs, found in 68 and 75% of honey samples at mean concentrations of 8.2 and 17.