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Medical Toxicology Commons

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Full-Text Articles in Medical Toxicology

Antidepressant Effects In Hybrid Striped Bass: Moving From External Exposures To Internal Doses, Lauren Sweet Aug 2015

Antidepressant Effects In Hybrid Striped Bass: Moving From External Exposures To Internal Doses, Lauren Sweet

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Over 47 percent of Americans take at least one prescription drug per month and of these pharmaceuticals, antidepressants are the third most prescribed drug. Their widespread and prolonged use coupled with incomplete removal during wastewater treatment processes has made them one of the most commonly detected pharmaceuticals in the aquatic environment. Antidepressants are intended to modify human behavior by altering brain chemistry and the neurotransmitter receptor targets of these chemicals are highly conserved in many vertebrate species; thus, aquatic organisms may be at risk. Previous research in our lab has shown that exposure of hybrid striped bass (HSB) (Morone saxatilis …


Ahr-Related Activities In A Creosote-Adapted Population Of Adult Atlantic Killifish, Fundulus Heteroclitus, Two Decades Post-Epa Superfund Status, Josephine Wojdylo Dec 2014

Ahr-Related Activities In A Creosote-Adapted Population Of Adult Atlantic Killifish, Fundulus Heteroclitus, Two Decades Post-Epa Superfund Status, Josephine Wojdylo

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Atlantic killifish, Fundulus heteroclitus, have adapted to, or at least developed a level of resistance to creosote-based polycyclic aromatic hydrocarbons (PAHs) found at the Atlantic Wood (AW) superfund site in the southern branch of the Elizabeth River, VA USA. Historically, 90+% of the mummichogs at this site have hepatic lesions of varying severity, and 30+% of these fish have tumors of various origin. Many xenobiotics, including select PAHs found at the Atlantic Wood site, are ligands for the aryl hydrocarbon receptor (AhR), which is a promiscuous ligand-dependent transcription factor involved in developmental regulation, environmental sensing, and induction of a suite …


A Characterization Of Gold Nanoparticle Uptake By Mammalian Cells, Thomas Garner Dec 2013

A Characterization Of Gold Nanoparticle Uptake By Mammalian Cells, Thomas Garner

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Over the past decade, there has been an exponential growth in products and applications that utilize nanotechnology, as these materials present exciting opportunities for the development of new products, enhancement of existing products, and the evolution of innovative procedures. However, this recent growth has occurred in the absence of detailed knowledge concerning the interactions of nanoparticles with biological systems. Nanoparticles must usually be bioavailable in order to elicit a biological response, and to reach an active site they must usually cross a membrane. As a result, cell culture studies have proven to be beneficial and are generally one of the …


Assessment Of 17beta-Estradiol Removal From Wastewater Via Abiotic And Biotic Routes And Potential Effects On Food Chain Pathways, Lance Beecher May 2013

Assessment Of 17beta-Estradiol Removal From Wastewater Via Abiotic And Biotic Routes And Potential Effects On Food Chain Pathways, Lance Beecher

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Estrone, 17beta-estradiol (E2), and estriol are three of the most relevant natural hormones and are often found to contaminate the environment. When emanating from endogenous sources, these three compounds are not toxic or of concern; however, when estrogens are released into the environment from wastewater effluent they become a concern. The overall goal of the project was to evaluate abiotic and biotic techniques for removal of E2 and to quantify survival and reproduction impacts on an algal species and on an invertebrate species. We accomplished this goal by: 1) quantifying E2 sorption rates to crushed brick, an industrial mineral aggregate …


Uptake And Toxic Effects Of Surface Modified Nanomaterials In Freshwater Aquatic Organisms, Brandon Seda May 2012

Uptake And Toxic Effects Of Surface Modified Nanomaterials In Freshwater Aquatic Organisms, Brandon Seda

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Nanomaterials are a class of materials with unique properties due to their size, and the association of these properties with the toxicity of nanomaterials is poorly understood. The present study assessed the toxic effects of stable aqueous colloidal suspensions of three distinctly different classes of nanomaterials in aquatic organisms. The fullerene, C70, was stabilized through non-covalent surface modification with gallic acid. Toxicity of C70-gallic acid was confirmed to exhibit similar toxic effects as C60-fullerene, including changes in antioxidative processes in Daphnia magna. Daphnia magna fecundity was significantly reduced in 21d bioassays at C70-gallic concentrations below quantifiable limits (0.03 mg/L C70). …


Arsenic Represses Myogenesis And Neurogenesis Through Epigenetic Mechanisms, Repressed Transcription Factors, And Altered Wnt Signaling Pathway, Gia-Ming Hong Dec 2011

Arsenic Represses Myogenesis And Neurogenesis Through Epigenetic Mechanisms, Repressed Transcription Factors, And Altered Wnt Signaling Pathway, Gia-Ming Hong

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Arsenic is a toxicant commonly found in water systems around the world. Evidence from epidemiological studies indicates that chronic arsenic exposure can result in cancer, central nervous system and sensory deficits, effects on development, and neuromuscular deficits. However, the molecular mechanism of arsenic's toxicity remains largely unclear. In this study, both C2C12 mouse myoblast cells and mouse embryonic stem cells (mESCs) were used as models of arsenic mediated developmental toxicity in humans to investigate the effects of sodium arsenite on cellular differentiation.
Results from our first and second studies indicate that exposure of 20nM sodium arsenite to C2C12 mouse myocyte …


Impacts Of Psychotropic Pharmaceuticals On Hybrid Striped Bass: Altered Predation Behavior As A Function Of Changes In Brain Chemistry, Joseph Bisesi Dec 2011

Impacts Of Psychotropic Pharmaceuticals On Hybrid Striped Bass: Altered Predation Behavior As A Function Of Changes In Brain Chemistry, Joseph Bisesi

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Advances in Analytical Chemistry have led to the detection of low concentrations of pharmaceuticals and personal care products (PPCPs) in wastewater treatment plant effluents as well as their receiving waters. Antidepressants are routinely found among these contaminants, but have been shown to be relatively non-toxic at environmentally measured concentrations using traditional toxicity testing techniques. The neurochemical mode of action of antidepressants warrants investigation of the effects these chemicals may have on fish behavior due to the highly conserved nature of neurotransmitter transporter targets. Using a predator prey bioassay designed in our laboratory, previous studies has shown that the antidepressant fluoxetine …


Lentiviral-Mediated Rnai Knockdown Yields A Novel Mouse Model For Studying Cyp2b Function, Basma Damiri Aug 2011

Lentiviral-Mediated Rnai Knockdown Yields A Novel Mouse Model For Studying Cyp2b Function, Basma Damiri

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The Cyp2b subfamily contains five members (Cyp2b9, Cyp2b10, Cyp2b13, Cyp2b19, and Cyp2b23) of which three (Cyp2b9, Cyp2b10, Cyp2b13) are hepatic enzymes involved in xenobiotic detoxification. In this study, we made a Cyp2b-knockdown mouse using lentiviral-promoted shRNA homologous to all five Cyp2b subfamily members in FVB/NJ mouse to characterize Cyp2b's role in xenobiotic detoxification. We assessed the in vivo function of Cyp2bs in the toxicity from pesticides (i.e. parathion) and drugs (i.e. zoxazolamine). We demonstrated that Cyp2b isoforms play a key role in parathion and Zoxazolamine metabolism and toxicity. In addition, we in partially phenotyped and characterized Cyp2b-KD model and assessed …


Didox Modulates Reactive Oxygen Species Production And Inflammatory Events Induced By Lipopolysaccharide (Lps) And Aryl Hydrocarbon Receptor (Ahr) Ligands In Raw 264.7 Murine Macrophages., Thabe Matsebatlela Aug 2009

Didox Modulates Reactive Oxygen Species Production And Inflammatory Events Induced By Lipopolysaccharide (Lps) And Aryl Hydrocarbon Receptor (Ahr) Ligands In Raw 264.7 Murine Macrophages., Thabe Matsebatlela

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Aberrant activation of macrophages during inflammation results in oxidative burst release of reactive oxygen and reactive nitrogen species (ROS/RNS) which are widely accepted to participate in pathogenesis of cancer, cardiovascular disease, atherosclerosis, hypertension, ischemia/reperfusion injury, diabetes mellitus, neurodegenerative diseases (Alzheimer's disease and Parkinson's disease), rheumatoid arthritis, and ageing. It is demonstrated here that Didox (3,4-Dihydroxybenzohydroxamic acid) possesses antioxidative and anti-inflammatory properties that can protect against inflammation and oxidative stress induced by lipopolysaccharide (LPS) and aryl hydrocarbon receptor (AHR) ligands (PCB126, E804, and IO) in Raw 264.7 murine macrophages. In brief, it is demonstrated here that Didox inhibits LPS-induced oxidative stress, …