Toxicology Commons^™

Nanoparticle Toxicity And Molecular Mechanisms In Fish: A Case Study With Silver Nanoparticles, Jiejun Gao

Open Access Dissertations

Nanoparticles (NPs) are widely used in a myriad of commercial and industrial products making their entry to the environment a likely event. NPs have unique physical-chemical properties that result from their small size and high surface area to volume ratio, making them highly reactive and potentially toxic. In Chapter 1, we summarize the effects and mechanisms of metal-based NPs on the vascular system. In vitro studies have shown that NPs are anti-angiogenic because they cause inflammation, oxidative stress, and apoptosis of endothelial cells resulting in increased permeability and decreased proliferation and migration. Whole animal studies examining the effects of NPs …

Analysis Of Synthetic Cannabinoids And Drugs Of Abuse Amongst Hiv-Infected Individuals, Jillian M. Wetzel

Student Theses

Synthetic cannabinoids are man-made mind-alternating chemicals. Law enforcement and legislation have attempted to classify many of these synthetic cannabinoids as schedule I controlled substances, however, they are continuously being modified by dealers at the retail end of the distribution chain. Addiction and moderate use of illicit drugs have been identified as major reasons for non-adherence to antiretroviral therapy among HIV patients. However, there is no data regarding the impact of synthetic cannabinoid exposure in this population and how this affects their compliancy with taking antiretroviral therapy. A total of 72 authentic urine specimens were collected weekly from 13 individuals with …

Gonadal Intersex In Teleosts: Mechanisms, Molecular Biomarkers And Diagnostic Assays, Ahmed M.E. Abdel-Moneim Mohamed

Open Access Dissertations

Natural and synthetic estrogenic and androgenic compounds are continuously released into aquatic ecosystems. Exposure of teleost fishes to these contaminants can negatively impact sex differentiation and reproductive output. Specifically, development of gonadal intersex in gonochoristic (fixed sex) fish species has been studied extensively in relation to exposure to this class of compounds. The main objectives of this dissertation were to: 1) conduct field and laboratory studies to investigate the molecular signaling pathways behind the development of gonadal intersex; and 2) establish molecular biomarkers and assays for testing the ability of environmental pollutants to develop this condition using a battery of …

Molecular Measurement Of Toxicity In Fish; Case Examples And Policy Implications, Jessica A. Freedman

Senior Honors Projects

Stormwater and oil are common urban contaminants that can be harmful to fish species. One way of recognizing exposed and impaired fish is by monitoring gene expression and gene induction. This study focused on the identification and validation of reference genes for measuring contaminant-induced changes in gene expression due to urban influence. In this study, reference genes (which are genes used to normalize data and remain consistent in varying exposures regardless of organism and tissue type) were established. Six genes were identified as reference genes (ef1a, wdtc1, mtm1, spop, rxrba and tuba1) from a longer list of potential …

The Relationship Between Lead In Groundwater And Elementary School Students' Academic Performance In Missouri, Lynnette Xiangling Li

MSU Graduate Theses

Lead exposure can come from various sources, e.g., lead mines, industrial areas, and lead based paint. Missouri has more than 4,128 lead mines. Lead is a neurotoxin. The objectives of the study were to investigate i) the spatial relationship between lead mines and lead distribution in groundwater, ii) the statistical impact of lead in groundwater on students' Missouri Assessment Program (MAP) scores, and iii) the geographic variations of lead's impact on students' MAP scores. Geographic Information Science spatial analysis tools were used to analyze the concentration of lead in groundwater within school districts in Missouri. Regression analysis was utilized to …

Use Of A Modified Greenscreen Tool To Conduct A Screening-Level Comparative Hazard Assessment Of Conventional Silver And Two Forms Of Nanosilver., Jennifer Sass, Lauren Heine, Nina Hwang

Environmental and Occupational Health Faculty Publications

BACKGROUND: Increased concern for potential health and environmental impacts of chemicals, including nanomaterials, in consumer products is driving demand for greater transparency regarding potential risks. Chemical hazard assessment is a powerful tool to inform product design, development and procurement and has been integrated into alternative assessment frameworks. The extent to which assessment methods originally designed for conventionally-sized materials can be used for nanomaterials, which have size-dependent physical and chemical properties, have not been well established. We contracted with a certified GreenScreen profiler to conduct three GreenScreen hazard assessments, for conventional silver and two forms of nanosilver. The contractor summarized publicly …

The Influence Of Oxygen Tension And Glycolytic And Citric Acid Cycle Substrates In Acrolein-Induced Cellular Injury In The Differentiated H9c2 Cardiac Cell Model, Jayme Coyle

USF Tampa Graduate Theses and Dissertations

Most in vitro systems employ the standard cell culture maintenance conditions of 95 % air with 5 % CO2 to balance medium pH, which translates to culture oxygen tensions of approximately 20 % - above the typical ≤ 6 % found in most tissues. The current investigation, therefore, aims to characterize the effect of maintenance and toxicant exposure with a particular focus on the α,β-unsaturated aldehyde, acrolein, in the presence of physiologically relevant oxygen tension using a differentiated H9c2 cardiomyoblast subclone. H9c2 cells were maintained separately in 20.1 and 5 % oxygen, after which cells were differentiated for five days, …

Aneuploidy: A Common And Early Evidence-Based Biomarker For Carcinogens And Reproductive Toxicants., Daniele Mandrioli, Fiorella Belpoggi, Ellen K Silbergeld, Melissa J. Perry

Environmental and Occupational Health Faculty Publications

Aneuploidy, defined as structural and numerical aberrations of chromosomes, continues to draw attention as an informative effect biomarker for carcinogens and male reproductive toxicants. It has been well documented that aneuploidy is a hallmark of cancer. Aneuploidies in oocytes and spermatozoa contribute to infertility, pregnancy loss and a number of congenital abnormalities, and sperm aneuploidy is associated with testicular cancer. It is striking that several carcinogens induce aneuploidy in somatic cells, and also adversely affect the chromosome compliment of germ cells. In this paper we review 1) the contributions of aneuploidy to cancer, infertility, and developmental abnormalities; 2) techniques for …

School Siting Near Industrial Chemical Facilities: Findings From The U.S. Chemical Safety Board's Investigation Of The West Fertilizer Explosion., Veronica A Tinney, Jerad M Denton, Lucy Sciallo-Tyler, Jerome A. Paulson

Environmental and Occupational Health Faculty Publications

BACKGROUND: The U.S. Chemical Safety and Hazard Investigation Board (CSB) investigated the April 17, 2013 explosion at the West Fertilizer Company (WFC) that resulted in 15 fatalities, more than 260 injuries and damage to more than 150 buildings. Among these structures were four nearby school buildings cumulatively housing children in grades K-12, a nursing care facility and an apartment complex. The incident occurred during the evening when school was not in session, which reduced the number of injuries.

OBJECTIVES: The goal of this paper is to illustrate the consequences of siting schools near facilities that store or use hazardous chemicals, …

Quantifying The Toxicity Of 1-Methylnaphthalene To The Shallow-Water Coral, Porites Divaricata, For Use In The Target Lipid Model, Nicholas Turner

HCNSO Student Theses and Dissertations

The proximity of coral reefs to coastal urban areas and shipping lanes predisposes corals to petroleum pollution from multiple sources. Previous research has evaluated petroleum toxicity to coral using a variety of methodologies, including monitoring effects of acute and chronic spills, in situ exposures, and ex situ exposures with both adult and larval stage corals. Variability in toxicant, bioassay conditions, species and other methodological disparities among studies prevents comprehensive conclusions regarding the toxicity of hydrocarbons to corals. This research evaluated the 48-hour toxicity of 1-methylnaphthalene to Porites divaricata using a continuous-flow passive dosing system. The range-finding exposure evaluated the dosing …

Synthetic And Biological Exploration Of (+)-Boldine - Identification Of Potential Cns Receptor Ligands, Sujay Joseph

Theses and Dissertations

(+)-Boldine, an aporphine alkaloid, is reported to be biologically active at various Central Nervous System(CNS) receptors. However, only a few Structure Activity Relationship(SAR) studies have been conducted using boldine’s aporphine scaffold. A library of novel analogs was synthesized from boldine to understand the effect of bisbenzylation at C2 and C9 positions on the affinity and selectivity at the serotonin receptors.

Manufacturer Perspectives On Content Transparency And Material Health In The Us Building Products Industry, Alexandra A. Muller

Open Access Theses

Flawed U.S. federal regulation of chemicals has resulted in a materials market that undervalues human and environmental health in favor of the more traditional attributes of price, performance and aesthetics. In the building products industry, global, dynamic supply chains and proprietary information concerns further complicate the task of assessing the material health of products.

Voluntary material health programs in the green building industry are intended to incentivize the manufacture and selection of safer products by getting companies to gather and assess ingredient, hazard and risk information from their supply chain. Building product manufacturers considered early adopters of the main material …

The Interactive Effects Of Pesticide Exposure And Infectious Disease On Amphibian Hosts, Katherine M. Pochini

Open Access Theses

Natural systems are home to a multitude of natural and anthropogenic stressors, which draw an array of effects on ecological communities. While these effects have been investigated individually, it is important, given the routine co-occurrence of these stressors, to understand their interactive effects. Pesticide exposure and infectious disease are two common, co-occurring stressors that each have documented detrimental effects on species and, as evidence suggests, may have interactive effects. Moreover, existing research suggests that these interactive effects are highly context dependent, eliciting different results based on species, disease agent, toxin, and environment. Given the variability with which species may experience …

Air Pollution, Pulmonary Oxidative Stress, And The Endothelin System In The Development Of Cardiovascular Injury., Jordan B. Finch

Electronic Theses and Dissertations

The goal of this project was to examine the role of endothelin-1 (ET-1) as a mediator in the pathway between air pollution exposure and the development of vascular injury. A human cohort and male mice (C57BL/6 and ecSOD-Tg) were used to evaluate changes in the ET-1 system in response to exposures of fine particulate matter (PM2.5). Human ET-1 levels were significantly associated with environmental factors and markers of vascular change, but were decreased with increased PM2.5. No association was seen between ET-1 and endothelial progenitor cells (EPCs) except for EPC-4, possibly indicating a regulatory relationship with this specific population. In …

The Current Scientific And Legal Status Of Alternative Methods To The Ld50 Test For Botulinum Neurotoxin Potency Testing, Sarah Adler, Gerd Bicker, Hans Bigalke, Christopher Bishop, Jörg Blümel, Dirk Dressler, Joan Fitzgerald, Frank Gessler, Heide Heuschen, Birgit Kegel, Andreas Luch, Catherine Milne, Andrew Pickett, Heidemarie Ratsch, Irmela Ruhdel, Dorothea Sesardic, Martin Stephens, Gerhard Stiens, Peter D. Thornton, René Thürmer, Martin Vey, Horst Spielmann, Barbara Grune, Manfred Liebsch

Martin Stephens, PhD

No abstract provided.

Bringing Toxicology Into The 21st Century: A Global Call To Action, Troy Seidle, Martin Stephens

Martin Stephens, PhD

Conventional toxicological testing methods are often decades old, costly and low-throughput, with questionable relevance to the human condition. Several of these factors have contributed to a backlog of chemicals that have been inadequately assessed for toxicity. Some authorities have responded to this challenge by implementing large-scale testing programmes. Others have concluded that a paradigm shift in toxicology is warranted. One such call came in 2007 from the United States National Research Council (NRC), which articulated a vision of ‘‘21st century toxicology” based predominantly on non-animal techniques. Potential advantages of such an approach include the capacity to examine a far greater …

A Caenorhabditis Elegans Model To Detect Developmental Teratogens With Adverse Reproductive And Metabolic Effects, Alexis Ann Killeen

USF Tampa Graduate Theses and Dissertations

Obesity is a current epidemic in the United States. Greater than one third of adults and nearly one fifth of children are classified as obese (Ogden, 2014). Increased awareness of this problem has triggered interest into the potentially causal agents in our environment. These agents, termed obesogens, are a type of teratogen hypothesized to work during embryonic development by programming offspring to store excess fat. A type of teratogen, obesogens are also typically reprotoxic, affecting germline development and embryonic viability. These noxious teratogens span a variety of different chemical classes including estrogen mimics, metals and metalloids, biocides, and even voluntary …

From Milpas To The Market: A Study On The Use Of Metal Silos For Safer And Better Storage Of Guatemalan Maize, José Rodrigo Mendoza

Department of Food Science and Technology: Dissertations, Theses, and Student Research

This project aimed to implement the use of metal silos to improve quality and safety of maize consumed by inhabitants of the highlands of Guatemala. This manuscript includes a literature review of the maize production chain in Guatemala, a survey about agricultural practices used in the region of study, as well as a characterization of the analyzed maize regarding its mycoflora, nutritional composition, and insect infestation. To better understand the current situation regarding agricultural practices and maize consumption, a survey was carried out. Sample consisted of 280 families representing 14 rural communities distributed in the townships of Todos Santos and …

Omics As Therapeutic Platform: Environmental Factors To Parkinson's Disease, Hong-Duck Kim, Shana Warner, Kamini Singh, Jae-Hyeon Cho, Diane E. Heck

NYMC Faculty Publications

No abstract provided.

Exploration Of Chemical And Biological Management Strategies For Diaphorina Citri The Primary Vector Of Candidatus Liberibacter Asiaticus, Gretta Marie Sharp

Biology Theses

Diaphorina citri (Hemipteran: Psyllidae), the Asian citrus psyllid, is a phloem-feeding, invasive species endemic to southern Asia that was first identified in the United States in Florida in 1998. Since introduction, D. citri has spread across the major citrus growing regions of the United States. This is of great concern to the citrus industry because D. citri is the primary vector of Candidatus Liberibacter asiaticus the causal agent of Haunglongbing (HLB). Haunglongbing is the most economically devastating disease of citrus causing an estimated 8.92 billion dollars lost in revenue and 4.62 billion dollars lost in gross domestic product between 2006-2007 …

4,4’-Dichlorodiphenyltrichloroethane (Ddt) And 4,4’-Dichlorodiphenyldichloroethylene (Dde) Promote Adipogenesis In 3tl1 Adipocyte Cell Culture, J Kim, Q Sun, Y Yue, Kyong-Sup Yoon, K -Y Whang, J M. Clark, Y Park

SIUE Faculty Research, Scholarship, and Creative Activity

4,4’-Dichlorodiphenyltrichloroethane (DDT), a chlorinated hydrocarbon insecticide, was extensively used in the 1940s and 1950s. DDT is mainly metabolically converted into 4,4’- dichlorodiphenyldichloroethylene (DDE). Even though most countries banned DDT in the 1970s, due to the highly lipophilic nature and very stable characteristics, DDT and its metabolites are present ubiquitously in the environment, including food. Recently, there are publications on relationships between exposure to insecticides, including DDT and DDE, and weight gain and altered glucose homeostasis. However, there are limited reports regarding DDT or DDE and adipogenesis, thus we investigated effects of DDT and DDE on adipogenesis using 3T3-L1 preadipocytes. Treatment …

Modification Of The In Vitro Uptake Mechanism And Anti-Oxidant Levels In Hacat Cells And Resultant Changes To Toxicity And Oxidative Stress Of G4 And G6 Poly (Amido Amine) Dendrimer Nanoparticles., Marcus Maher, Hugh Byrne

Articles

The mechanism of cellular uptake by endocytosis and subsequent oxidative stress has been identified as the paradigm for the toxic response of cationically surface charged nanoparticles. In an attempt to circumvent the process, the effect of increased cellular membrane permeability on the uptake mechanisms of poly (amidoamine) dendrimers generation 4 (G4) and 6 (G6) in vitro was investigated. Immortalised, non-cancerous human keratinocyte (HaCaT) cells were treated with DL-Buthionine-(S,R)-sulfoximine (BSO). Active uptake of the particles was monitored using fluorescence microscopy to identify and quantify endosomal activity and resultant oxidative stress, manifest as increased levels of reactive oxygen species, monitored using the …

Polychlorinated Biphenyl (Pcb) Pollution Of The Hudson River: Social Policy And Health Considerations, Laura Schad

Honors Theses

The purpose of this paper is to examine pollution in the Hudson River and the role General Electric has had in creating this problem. The focus will be on social issues and problems that have emerged as a result of the environmental damage from pollution. Until recently, there was little research done on the health and environmental justice issues that impact the New York communities where GE’s factories were located. This paper examines the material collected and studies that were done which document Hudson River pollution and the contributions as well as cleanup efforts of General Electric. The overall problems …

Consequences Of 2,3,7,8-Tetrachlorodibenzo-P-Dioxin (Tcdd) On Hepatic Stellate Cell Activation And Extracellular Matrix Remodeling During Chronic Liver Injury, Cheri Lou Lamb

Boise State University Theses and Dissertations

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a persistent environmental pollutant and high-affinity ligand for the aryl hydrocarbon receptor (AhR). Exposure to TCDD elicits a spectrum of toxic effects, many involving aberrant cell proliferation, activation, and differentiation. The liver is a target organ for TCDD toxicity, and increasing evidence indicates that AhR signaling regulates genes that coordinate deposition and remodeling of the extracellular matrix (ECM) in the liver. Hepatic stellate cells (HSCs) are central to ECM remodeling in the liver. We recently reported that TCDD treatment increases the activation of human HSCs in vitro. The goal of this study was to …

Investigating The Effects Of 17Α-Ethynylestradiol On Mitochondrial Genome Stability, Alicia M. Chivers

Dissertations and Theses

Environmental toxicants are ubiquitous throughout the environment as a result of human activity. Among these toxicants, environmental estrogens are a category of particular concern due to their environmental prevalence and potency in altering reproductive traits. While many studies have addressed the detrimental effects of environmental estrogens on both aquatic and terrestrial organisms, few have analyzed the potential for these compounds to alter mitochondrial function. Mitochondria are the primary energy-generating system for all eukaryotic life, supporting all aspects of development, metabolism, and growth. Each cell within the body contains many mitochondria which in turn contain multiple copies of their own DNA …

Investigations Of The Effects Of Different Ventilation Structures On Physiologically Based Pharmacokinetic Modeling (Pbpk) Simulations, Karen A. Yokley

Biology and Medicine Through Mathematics Conference

No abstract provided.

Effect Of Bisphenol-A On Neurodevelopment In Drosophila Melanogaster Larvae, Alexandra M. Streifel

All College Thesis Program, 2016-2019

This paper examines the effects of the chemical preservative bisphenol-A on the developing nervous systems of Drosophila melanogaster, or fruit fly, larvae. This study examines the effects of bisphenol-A using both behavioral as well as morphological paradigms. It was determined that bisphenol-A significantly increased the amount of time larvae spent in seeking behavior, the number of peristaltic contractions, and the distance traveled in a linear fashion. In the morphological analysis, indications of increased dendritic area in experimental larvae existed, but there was not enough data to determine significance. For future research, it is recommended that more data be gathered to …

Comparing The Quantitation Of Opiates From Possible Drug Overdose Cases Using Results Of Blood Analysis And Liver Analysis, Lee Ann Garozzo

Forensic Science Theses

Currently the quantitation of opiates at the Erie County Medical Examiner’s Office Toxicology Laboratory is conducted through whole blood analysis. The objective of this thesis project was to determine if the analysis of opiates could be conducted through liver analysis, and if the analysis of opiates would provide a more accurate quantitation compared to the blood analysis. The quantitation of opiates was conducted from the livers of sixty-four possible overdose cases that were brought into the Erie County Medical Examiner’s Office between 2013 and 2015. Results showed that the opiate drugs could successfully be quantitated using the liver analysis. Generally …

The Emergence Of Systematic Review In Toxicology, Martin L. Stephens, Kellyn Betts, Nancy Beck, Vincent Cogliano, Kay Dickersin, George Gray, +8 Additional Authors

Environmental and Occupational Health Faculty Publications

The Evidence-based Toxicology Collaboration hosted a workshop on “The Emergence of Systematic Review and Related Evidence-based Approaches in Toxicology,” on November 21, 2014 in Baltimore, Maryland. The workshop featured speakers from agencies and organizations applying systematic review approaches to questions in toxicology, speakers with experience in conducting systematic reviews in medicine and healthcare, and stakeholders in industry, government, academia, and non-governmental organizations. Based on the workshop presentations and discussion, here we address the state of systematic review methods in toxicology, historical antecedents in both medicine and toxicology, challenges to the translation of systematic review from medicine to toxicology, and thoughts …

Evaluating The Cytotoxic Effects Of Cellulose Nanocrystals (Cncs) Using Autobioluminescent Yeast And Human Cells, Julianna Hughes Burchett

EURēCA: Exhibition of Undergraduate Research and Creative Achievement

Cellulose nanocrystals (CNCs) are widely used in different industries including pharmaceutical and cosmetic production due to their adept physical and biological properties. Because CNCs are becoming a more prevalent material and have a high potential of being redistributed in the environment, it is important to understand their toxic potentials in biological systems, including organisms of various trophic levels. This study evaluated the cytotoxic effects of CNCs in the lower eukaryotic organism Saccharomyces cerevisiae and human embryonic kidney (HEK293) cells using autobioluminescent yeast and human cell reporters, respectively. The S. cerevisiae and HEK293 reporter cells were engineered to express a synthetic …