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Toxicology Commons

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Hexavalent Chromium-Induced Cytotoxicity And Mutagenicity: A Study Of Protection By Ascorbic Acid And Epigallocatechin Gallate, Timothy P. Mayotte 2019 Olivet Nazarene University

Hexavalent Chromium-Induced Cytotoxicity And Mutagenicity: A Study Of Protection By Ascorbic Acid And Epigallocatechin Gallate, Timothy P. Mayotte

Honors Program Projects

Hexavalent chromium, or Cr(VI), is a potent oxidizer and known carcinogen, that is found at varying levels in the water sources of more than 200 million Americans. However, the exact mechanism of carcinogenicity remains unknown, and though the government currently regulates total chromium levels, they have yet to determine a permissible exposure limit for Cr(VI). Moreover, there is currently no preventative treatment for Cr(VI). Because of Cr(VI)’s strong oxidative power, we hypothesized that it causes DNA mutation and cell death via oxidation and that antioxidants could prevent this from occurring. To test this, we first ...


Development And Validation Of A Lc-Ms/Ms Method For Detection And Quantification Of 18 Antidepressants In Whole Blood, Linda Kim 2019 CUNY John Jay College

Development And Validation Of A Lc-Ms/Ms Method For Detection And Quantification Of 18 Antidepressants In Whole Blood, Linda Kim

Student Theses

Antidepressants are one of the most commonly prescribed drugs in America, with researchers reporting one in six Americans take some form of psychiatric drugs-mostly antidepressants (NBC News, 2016). Antidepressants are often present in combination with other drugs in suicides and drug-related deaths, so a sensitive and specific method to detect and quantify antidepressants is necessary. We developed a method for the detection and quantification of 18 different antidepressants in whole blood, with a range of 2.5-900 ng/mL and LOQ of 2.5 ng/mL. Three hundred uL of blood was used and the analytes were extracted using solid-phase ...


Integrating Online Instruction And Hands-On Laboratory Activities For Summer Learning For Students Of Color: A Design Case In Forensic Science, Douglas Elrick, Jiaqi Yu, Connie Hargrave 2019 Iowa State University

Integrating Online Instruction And Hands-On Laboratory Activities For Summer Learning For Students Of Color: A Design Case In Forensic Science, Douglas Elrick, Jiaqi Yu, Connie Hargrave

Constance P. Hargrave

The popularity of TV shows such as Crime Scene Investigation (CSI) has generated high school students’ interest in forensics. Yet, forensic science is not commonly accessible to students, and especially students of color who often attend under-resourced high schools. This article presents the design, development, and evaluation of an online forensics course created for high school students of color who were a part of an informal science, technology, engineering, and mathematics (STEM) educational development program. Two essential elements guided the course design: the target learners (high school students of color) and integrating online instruction and hands-on laboratory activities involving real-world ...


Studying The Effects Of Electronic Cigarette Exposure On Dna Mutation And Repair In Tetrahymena Thermophila, Tianna Sell, Katie Huisman, Matt F. Kvech 2019 Carroll College

Studying The Effects Of Electronic Cigarette Exposure On Dna Mutation And Repair In Tetrahymena Thermophila, Tianna Sell, Katie Huisman, Matt F. Kvech

Carroll College Student Undergraduate Research Festival

The purpose of our experiment was to answer the question: Does exposure to aerosols expelled from an electronic cigarette affect the APN2 gene expression in Tetrahymena thermophila? It was hypothesized that the expression of APN2 would increase in Tetrahymena that were exposed to aerosol from a vape and that their growth rate would decrease. The mechanism and function of the APN2 gene is known as base excision repair. To test the hypothesis, Tetrahymena were randomly assigned to either a control group or a test group. A contraption was created to extract 12mL of aerosol from a Smok Baby Beast vape ...


Effect Of Bis (2-Ethylhexyl) Phthalate On Tetrahymena Thermophila Dcl-1 Gene Expression And Conjugation, Talya Vaira, Peyton Twete 2019 Carroll College

Effect Of Bis (2-Ethylhexyl) Phthalate On Tetrahymena Thermophila Dcl-1 Gene Expression And Conjugation, Talya Vaira, Peyton Twete

Carroll College Student Undergraduate Research Festival

Phthalates, often referred to as plasticizers, are a group of chemicals used in hundreds of products including detergents, food packaging, and nail polish. Bis (2-ethylhexyl) phthalates (DEHP) have recently been shown to disrupt endocrine chemical balances, thereby causing reproductive strain. For this project, we wanted to explore how DEHP influences conjugation in Tetrahymena thermophila and to determine how DEHP exposure affects expression of the DCL-1 gene. The DCL-1 gene encodes the protein DCL-1 which is essential for transmitting genetic information during the process of conjugation in T. thermophila. We hypothesized that DEHP will act as a repressor of conjugation resulting ...


Hexavalent Chromium: Elucidating Its Carcinogenic Mechanism, And Testing Potential Preventative Treatments, Ryan Himes, Timothy Mayotte 2019 Olivet Nazarene University

Hexavalent Chromium: Elucidating Its Carcinogenic Mechanism, And Testing Potential Preventative Treatments, Ryan Himes, Timothy Mayotte

Scholar Week 2016 - present

Cr(VI) (hexavalent chromium) has recently been found in the drinking water of over 250 million Americans. It is a powerful oxidizing agent, and is known to cause cancer, although the specific mechanism has yet to be elucidated. There is no known preventative treatment for Cr(VI) exposure, and the US EPA is currently determining what concentration of Cr(VI) in drinking water can be safely tolerated. This study sought to test the hypothesis that Cr(VI) cytotoxicity can be prevented by various antioxidants. We tested this hypothesis by exposing human embryonic kidney and human intestinal epithelial cells to Cr ...


Evaluation Of Semi-Continuous Pit Manure Recharge System Performance On Mitigation Of Ammonia And Hydrogen Sulfide Emissions From A Swine Finishing Barn, Jisoo Wi, Seunghun Lee, Eunjong Kim, Myeongseong Lee, Jacek A. Koziel, Heekwon Ahn 2019 Chungnam National University

Evaluation Of Semi-Continuous Pit Manure Recharge System Performance On Mitigation Of Ammonia And Hydrogen Sulfide Emissions From A Swine Finishing Barn, Jisoo Wi, Seunghun Lee, Eunjong Kim, Myeongseong Lee, Jacek A. Koziel, Heekwon Ahn

Agricultural and Biosystems Engineering Publications

In this research, for the first time, we present the evaluation of a semi-continuous pit manure recharge system on the mitigation of ammonia (NH3) and hydrogen sulfide (H2S) emissions from a swine finisher barn. The pit recharge system is practiced on many swine farms in the Republic of Korea, primarily for improving air quality in the barn. It consists of an integrated waste management system where the fraction of stored manure is pumped out (10× of the daily production of manure, 3× a day); solids are separated and composted, while the aerobically treated liquid fraction is then returned to the ...


Herbicide Toxicity To Non-Target Aquatic Organisms Does Not Increase In Mixtures With Surfactants, Courtney L. Telfort 2019 Georgia Southern University

Herbicide Toxicity To Non-Target Aquatic Organisms Does Not Increase In Mixtures With Surfactants, Courtney L. Telfort

University Honors Program Theses

Agricultural herbicides enter aquatic environments after rain events where they affect microscopic aquatic plants (phytoplankton) and animals (zooplankton) that form the base of aquatic food webs. Atrazine, an herbicide with low solubility in water, is often mixed with surfactants such as alkyl polyglucoside (APG) to improve effectiveness. Although APG has low-toxicity, a potential drawback to increased atrazine solubility is greater adverse effects on aquatic organisms. I hypothesized that atrazine and APG decrease phytoplankton abundance more than atrazine alone. Specifically, I predicted phytoplankton abundance should 1) decrease with increasing concentrations of the mixture compared to the same atrazine concentrations individually, and ...


M22 Hormesis In Mouse Embryonic Stem Cell Models, Alexa Mejorada 2019 University of Colorado, Boulder

M22 Hormesis In Mouse Embryonic Stem Cell Models, Alexa Mejorada

Undergraduate Honors Theses

Cryoprotectant toxicity (CT), or the injury due to cryoprotectant (CPA) exposure, remains the most limiting barrier to performing successful organ cryopreservation. An intervention alleviating the stress induced by CT in mouse embryonic stem cell (mESC) models may translate well into tissue and organ models of cryopreservation. Such discoveries could enable large-scale organ banking and, potentially, end the transplantable-organ shortage. In this study, I sought to see if CT could be combated through a hormetic approach. Hormesis will be defined as the negation of the detrimental effects of a high, lethal dosage of a stressor via a prior nonlethal dosage of ...


Prevention Of Crystalline Silica-Induced Inflammation By The Anti-Malarial Hydroxychloroquine, Rachel Dawn Burmeister 2019 University of Montana

Prevention Of Crystalline Silica-Induced Inflammation By The Anti-Malarial Hydroxychloroquine, Rachel Dawn Burmeister

Graduate Student Theses, Dissertations, & Professional Papers

Exposure to inhaled crystalline silica (cSiO2) is common in occupations where there is cutting, milling, or grinding of cSiO2 containing material. The Occupational Safety and Health Administration estimates that over 2 million workers may be exposed to inhaled cSiO2 in the United States. Inhalation of cSiO2 causes acute and chronic inflammation and may lead pulmonary diseases such as silicosis, as well as an increased risk of developing autoimmune diseases.Unfortunately, treatment of cSiO2-induced lung diseases is limited and primarily focused on supportive care.

Inflammation caused by cSiO2 begins when, cSiO2 particles are phagocytized by alveolar macrophages. Interaction between the particle ...


Analysis Of Synthetic Opioids In Postmortem Blood, Vitreous Humor, And Brain Tissue, Rachel K. Chesser 2018 CUNY John Jay College

Analysis Of Synthetic Opioids In Postmortem Blood, Vitreous Humor, And Brain Tissue, Rachel K. Chesser

Student Theses

In the United States, the use of new synthetic opioids (e.g. fentanyl and derivatives) has become an increasing health issue with thousands of overdose deaths being observed since 2013. With the high mortality rate associated with these substances, postmortem analyses and interpretation of synthetic opioids has become extremely important. However, due to the novelty of these compounds, the available data is limited and provides challenges to toxicologists. The focus of this project was to examine the postmortem distribution of new synthetic opioids in blood, vitreous humor, and brain tissue. New methods were developed and validated to quantify 13 synthetic ...


Aptamer-Based Assay For Detection Of Ochratoxin A, Amanda Nicole Bartley 2018 Florida International University

Aptamer-Based Assay For Detection Of Ochratoxin A, Amanda Nicole Bartley

FIU Electronic Theses and Dissertations

Ochratoxin A (OTA) is a potent mycotoxin found in a wide range of agricultural products that has been linked to mitochondrial damage and renal disease. The standard methods for OTA analysis currently rely on the use of high-performance liquid chromatography (HPLC) coupled to fluorescence detection or mass spectrometry. Toward a highthroughput analysis of OTA, a single-stranded DNA aptamer, modified with a fluorophore, coupled to a complementary sequence, modified with a FRET-based quencher that dissociates in the presence of the target toxin, is proposed. In order to integrate “target trapping,” aptamer immobilization methods were explored to mediate interference issues. Assays were ...


45 - The Sublethal Effects And Bioaccumulation Of 17a-Ethinyl Estradiol In Lumbriculus Variegatus, Kikelomo Ogunsemore 2018 Augusta University

45 - The Sublethal Effects And Bioaccumulation Of 17a-Ethinyl Estradiol In Lumbriculus Variegatus, Kikelomo Ogunsemore

Georgia Undergraduate Research Conference (GURC)

The threat of freshwater scarcity is a global concern. With less than 1% of Earth’s total water available for human consumption, there has been concern about toxic contaminants affecting available freshwater sources.

Freshwater sources are subject to contamination from toxic compounds and other harmful materials through improper sewage cleanup and pollution. Ethinyl estradiol, a synthetic, steroidal estrogen used in contraception, is present in varying concentrations across freshwater sources worldwide. Ethinyl estradiol (EE) is also classified as an endocrine disruptor that is known to interfere with the endocrine system. Endocrine disruptors can create adverse effects on bodily systems and have ...


Optimization Of Time-Weighted Average Air Sampling By Solid-Phase Microextraction Fibers Using Finite Element Analysis Software, Bulat Kenessov, Jacek A. Koziel, Nassiba Baimatova, Olga P. Demyanenko, Miras Derbissalin 2018 Al-Farabi Kazakh National University

Optimization Of Time-Weighted Average Air Sampling By Solid-Phase Microextraction Fibers Using Finite Element Analysis Software, Bulat Kenessov, Jacek A. Koziel, Nassiba Baimatova, Olga P. Demyanenko, Miras Derbissalin

Agricultural and Biosystems Engineering Publications

Determination of time-weighted average (TWA) concentrations of volatile organic compounds (VOCs) in air using solid-phase microextraction (SPME) is advantageous over other sampling techniques, but is often characterized by insufficient accuracies, particularly at longer sampling times. Experimental investigation of this issue and disclosing the origin of the problem is problematic and often not practically feasible due to high uncertainties. This research is aimed at developing the model of the TWA extraction process and optimization of TWA air sampling by SPME using finite element analysis software (COMSOL Multiphysics, Burlington, MA, USA). It was established that sampling by porous SPME coatings with high ...


The Value Of Chemical Defense: The Effects Of Toxin Milking On The Physical, Physiological, And Behavioral Performance Of Cane Toads (Rhinella Marina), Ryann Blennerhassett 2018 SIT Study Abroad

The Value Of Chemical Defense: The Effects Of Toxin Milking On The Physical, Physiological, And Behavioral Performance Of Cane Toads (Rhinella Marina), Ryann Blennerhassett

Independent Study Project (ISP) Collection

Amphibians have cutaneous glands on their skin which produce a number of toxic compounds that serve as protection against predators and microorganisms. Cane toads (Rhinella marina) have large parotoid glands located on their shoulders to store toxins, many of which are derived from lipids and are thus energetically expensive to produce. I used a combination of field and laboratory studies to investigate behavioral and physiological consequences of toxin loss and replenishment in cane toads. In a cross-sectional study, free-ranging toads were euthanized and dissected to identify correlations between toxin content and morphology /physiology. Experimental manipulations (manually expressing toxin from glands ...


Effect Of Arsenic Exposure On Early Eye Development In Zebrafish (Danio Rerio), Remy S. Babich 2018 University of Maine

Effect Of Arsenic Exposure On Early Eye Development In Zebrafish (Danio Rerio), Remy S. Babich

Electronic Theses and Dissertations

Arsenic is a metalloid that contaminates drinking water supplies worldwide. Due to concerns for human health, the World Health Organization (WHO) and the U.S. Environmental Protection Agency (EPA) have established a safe level in drinking water of ≤ 10 ppb. Arsenic has been shown to have carcinogenic effects in humans at high and low doses. Chronic exposure may result in dermal conditions such as hyperkeratosis and hyperpigmentation. Recently, arsenic exposure has also been linked to lower IQ values in children. The effect of arsenic on neurogenesis, specifically eye development, has not been widely explored. This study aimed to examine the ...


A Review Of Inhalation Exposure To Mold And Adverse Health Outcomes, Amanda S. Persad, Todd Stedeford, Marek Banasik, Tomasz T. Suchecki, Carlos A. Muro-Cacho 2018 Florida State University College of Law

A Review Of Inhalation Exposure To Mold And Adverse Health Outcomes, Amanda S. Persad, Todd Stedeford, Marek Banasik, Tomasz T. Suchecki, Carlos A. Muro-Cacho

Florida State University Journal of Land Use and Environmental Law

No abstract provided.


Mycotoxins: Mechanisms For Toxicity And Methods For Identifying Exposed Individuals, Carlos A. Muro-Cach, Todd Stedeford, Marek Banasik, Tomasz T. Suchecki, Amanda S. Persad 2018 Florida State University College of Law

Mycotoxins: Mechanisms For Toxicity And Methods For Identifying Exposed Individuals, Carlos A. Muro-Cach, Todd Stedeford, Marek Banasik, Tomasz T. Suchecki, Amanda S. Persad

Florida State University Journal of Land Use and Environmental Law

No abstract provided.


Toxicology And Risk Assessment Of Mycotoxins, Raymond D. Harbison, Todd Stedeford, Marek Banasik, Carlos A. Muro-Cacho 2018 Florida State University College of Law

Toxicology And Risk Assessment Of Mycotoxins, Raymond D. Harbison, Todd Stedeford, Marek Banasik, Carlos A. Muro-Cacho

Florida State University Journal of Land Use and Environmental Law

No abstract provided.


Evaluation Of Drug-Loaded Gold Nanoparticle Cytotoxicity As A Function Of Tumor Tissue Heterogeneity., Hunter Allan Miller 2018 University of Louisville

Evaluation Of Drug-Loaded Gold Nanoparticle Cytotoxicity As A Function Of Tumor Tissue Heterogeneity., Hunter Allan Miller

Electronic Theses and Dissertations

The inherent heterogeneity of tumor tissue presents a major challenge to nanoparticle-medicated drug delivery. This heterogeneity spans from the molecular to the cellular (cell types) and to the tissue (vasculature, extra-cellular matrix) scales. Here we employ computational modeling to evaluate therapeutic response as a function of vascular-induced tumor tissue heterogeneity. Using data with three-layered gold nanoparticles loaded with cisplatin, nanotherapy is simulated with different levels of tissue heterogeneity, and the treatment response is measured in terms of tumor regression. The results show that tumor vascular density non-trivially influences the nanoparticle uptake and washout, and the associated tissue response. The drug ...


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