Toxicology Commons^™

Remobilization Of Heavy Metals By Mangrove Leaves, Hanan Almahasheer, Oscar Serrano, Carlos M. Duarte, Xabier Irigoien

Research outputs 2014 to 2021

Several studies have been carried out on heavy metal pollution in mangrove ecosystems. However, the role of mangroves in heavy metal remobilization is still relatively unknown. On one side, mangrove woody organs and soils sequester heavy metals for long time periods, but on the other hand, senescence of mangrove leaves may return these metals collected by roots to the upper layers of the soil. Here, we analyzed the concentration of chemical elements (Al, As, Cd, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Sr, V, and Zn) as a function of age in mangrove leaves to understand heavy metals retention by …

The Influence Of Physiological And Abiotic Factors On The Sensitivity Of The Sea Lamprey (Petromyzon Marinus) To The Lampricide 3-Trifluoromethyl-4-Nitrophenol (Tfm), Alexandra Muhametsafina

Theses and Dissertations (Comprehensive)

Invasive sea lamprey (Petromyzon marinus) in the Great Lakes are controlled using the pesticide (lampricide) 3-trifluoromethyl-4-nitrophenol (TFM), which is applied to nursery streams containing larval lamprey. The toxicity of TFM to lamprey is affected by various environmental and physiological factors, which can lead to residual lamprey that survive TFM treatment. The goal of this study was to investigate how abiotic (season and temperature) factors interacted with physiological parameters (whole body and tissue energy reserves) to influence TFM sensitivity in sea lamprey. Toxicity tests were conducted at different times of the year (spring, early and late summer, fall) and …

Forensic Markers Of Lampricide Toxicity In Oncorhynchsus Mykiss, Chris White

Theses and Dissertations (Comprehensive)

The lampricide 3-trifluoromethyl-4-nitrophenol (TFM) has been used for decades to control invasive sea lamprey (Petromyzon marinus) populations in the Great Lakes, normally with little harm to other fish populations. However, due to the nature of lampricide treatments and the chemical properties of TFM, adverse effects to non-target fishes and non-target mortality occasionally occur. However, investigations of non-target mortality can be complex, particularly if fish deaths are not noticed immediately, due to decomposition of the carcasses. The objectives of this thesis were to expose rainbow trout (Oncorhynchsus mykiss) to TFM in order to: (i) identify forensic markers …

The Effects Of The Red Tide Producing Dinoflagellate, Karenia Brevis, And Associated Brevetoxins On Viability And Sublethal Stress Responses In Scleractinian Coral: A Potential Regional Stressor To Coral Reefs, David A. Reynolds

UNF Graduate Theses and Dissertations

Coral cover is in decline on a global scale, with increased mortality events being attributed to a number of global and regional stressors. While the impacts of global stressors (e.g. sea surface temperature rise, ocean acidification) are well documented, there is growing interest in identifying and understanding the impacts of regional stressors. The reason for this change in focus is that regional stressors can often work in combination, sometimes synergistically, with global stressors and that stressors on a regional scale tend to be more easily mitigated by management practices. One regional stressor that impacts a myriad of marine organisms in …

Testing The Underlying Chemical Principles Of The Biotic Ligand Model (Blm) To Marine Copper Systems: Measuring Copper Speciation Using Fluorescence Quenching, Tara N. Tait, James C. Mcgeer, Scott Smith

Chemistry Faculty Publications

Speciation of copper in marine systems strongly influences the ability of copper to cause toxicity. Natural organic matter (NOM) contains many binding sites which provides a protective effect on copper toxicity. The purpose of this study was to characterize copper binding with NOM using fluorescence quenching techniques. Fluorescence quenching of NOM with copper was performed on nine sea water samples. The resulting stability con- stants and binding capacities were consistent with literature values of marine NOM, show- ing strong binding with log K values from 7.64 to 10.2 and binding capacities ranging from 15 to 3110 nmole mg C ^{−1 …}

9-Aminoacridine Inhibits Ribosome Biogenesis And Synergizes With Cytotoxic Drugs To Induce Selective Killing Of P53-Deficient Cells, Leonid Anikin, Dimitri G Pestov

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Common cancer treatments target rapidly dividing cells and do not discriminate between cancer and normal host cells. One approach to mitigating negative side‐effects of cancer treatment is to temporarily arrest cell cycle progression and thus protect normal cells during cytotoxic treatments, a concept called cyclotherapy. We recently proposed that transient inhibition of post‐transcriptional steps of ribosome biogenesis (RBG) can be used to selectively arrest p53‐positive host cells and not p53‐null cancer cells. In this study, we investigated whether cytoprotective RBG inhibition can be achieved through small molecule treatment.

Effects Of Crude Oil On Tumor Suppressor P53 Polymorphisms In Laboratory-Exposed Atlantic Killifish, Fundulus Heteroclitus, Allison Margaret Nadler

Seton Hall University Dissertations and Theses (ETDs)

Polycyclic aromatic hydrocarbons (PAHs), constituents of crude oil, are implicated as a potent source of adverse toxicological effects on living organisms. To model the effects of PAHs in response to environmental oil spill disasters a species of killifish (Fundulus heteroclitus) was captured and exposed to crude oil in a laboratory-controlled setting. Over a period of 7 days, fish were dosed with crude oil by gavage, culled, and organs were harvested for analysis. Excitation-emission matrix spectroscopy (EEMS) of gall bladder tissue homogenates was used to verify exposure. Effects of PAHs on the p53 gene were evaluated as an indicator …

Organizational Effects Of Defeminizing Toxicants: Lessons Learned From An Environmental Sentinel Organism, The Fathead Minnow., Jonathan Ali

Theses & Dissertations

Endocrine disrupting compounds (EDCs) are chemicals that interfere with hormone function and are increasingly detected in aquatic environments, where they elicit adverse effects from exposed organisms. The toxicological effects of EDCs can be described as either activational (reversible) or organizational (irreversible), where the latter are associated with adverse outcomes in reproductive performance of adult fish. However, few studies have investigated the organizational impacts of anti-estrogenic or “defeminizing” EDCs, e.g. agrichemicals or pharmacological agents, in an environmentally-relevant or “sentinel” species. The objective of this study was to investigate the impacts of early-life EDC-initiated changes in estrogenic gene expression on organizational effects …

Identification And Quantification Of Cyanide And Its Metabolites In Lemur Urine, Jeremy Peralta

Student Theses

Cyanide is a chemical compound that contains the monovalent groups of carbon and nitrogen. This substance is considered a rapidly acting deadly chemical. However, some animals such as lemurs consume food products that are known to contain elevated levels of cyanide without major consequences. The mechanism by which the lemur can handle this high exposure to cyanide is unknown. In this study, we developed and validated two analytical methods for the determination of cyanide and two metabolites, thiocyanate and 2-aminothiazoline-4-carboxylic acid (ATCA) in lemur urine. The method was applied to 47 authentic lemur urine samples collected from 4 different species …

Toxicity And Mitochondrial Delivery Of Flavonol-Based Carbon Monoxide-Releasing Molecules, Hector Jose Esquer Heredia

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Despite the reputation of carbon monoxide (CO) as a silent killer, new evidence suggests that this gaseous molecule has anti-inflammatory, anti-cancer and vasoprotective properties. Unfortunately, little is known about the role of CO in the body. However, proteins present in mitochondria are believed to be important targets. We previously synthesized a class of novel and structurally modifiable flavonol-based CO-releasing molecules (CORMs). Flavonols are commonly found in fruits and vegetables. The base structure, Flav-1, is fluorescent, exhibits low toxicity, and releases CO after exposure to visible light. Previous reports indicate that addition of a triphenylphosphonium (TPP) tail allows chemical structures to …

Age-Related Host Factors Regulate Lung Cancer Progression., John Caleb Greenwell

Electronic Theses and Dissertations

Cancer is largely a disease of the elderly. In the United States alone, 87% of all cancers in 2017 will be diagnosed in individuals aged 50 years or older. Among them, lung cancer is the deadliest, accounting for 1 in 4 cancer deaths. The 5-year survival rate is below 20%, a number which has not changed substantially over the past several decades. This underscores a desperate need for new strategies in prevention, early detection and treatment of this deadly disease. While tobacco use is unquestionably the number one risk factor for the development of lung cancer, the majority of diagnoses …

Activation Des Éosinophiles Humains Par Des Nanoparticules, Denis Girard, Maxime Marion-Murphy

Rapports de recherche scientifique

L’économie du Canada, comme celle de bien d’autres pays industrialisés, bénéficie du développement des nanotechnologies dont le fort potentiel peut être exploité dans plusieurs secteurs industriels. Un nombre croissant d’entreprises québécoises de production de nanoparticules (NP) est d’ailleurs déjà implanté et tout porte à croire que d’autres emboîteront le pas dans les années à venir. Ce faisant, non seulement le nombre de travailleurs œuvrant dans la fabrication et la synthèse des NP augmentera sensiblement, mais également le nombre de ceux qui seront appelés à en manipuler et à en transformer dans les domaines des nanotechnologies en général. Une des conséquences …

A Historical Assessment Of Asbestos Exposure, Abatement Methods And Containment Efficacy During Asbestos Containing Material Removal Activities At A Large Federal Facility, Daniel A. Newfang

USF Tampa Graduate Theses and Dissertations

Asbestos sampling and monitoring data, starting from 2003, located in a large federal facility’s Asbestos Air Database Management (AADM) repository will be queried and analyzed on airborne asbestos fiber concentrations generated from abatement activities of asbestos-containing materials (ACM) and asbestos-containing building materials (ACBM). Historically, concerns expressed by personnel outside of the containment areas, whether adjacent to or quite a distance from the asbestos abatement activities present operational challenges for the project manager, potential angst and uneasiness to personnel residing next to the abatement activity as well as programmatic concerns to the building/facility managers. The concerned individuals working outside the abatement …

Multigeneration Effects Of Chronic Exposure To Polycyclic Aromatic Hydrocarbons In Gulf Killifish (Fundulus Grandis), Andrea Yammine

LSU Master's Theses

The goal of this study was to examine potential adaptation within two generations of Gulf killifish exposed to polycyclic aromatic hydrocarbons (PAH) while also investigating the use of mucus as an effective and non-lethal alternative to determine concentrations of 11-ketotestosterone (11-KT) and vitellogenin (VTG) of F. grandis. Multiple biomarkers were used to assess adaptation within these fish, such as lysozyme (enzyme critical in innate immunity), and 11-ketotestosterone and vitellogenin (endocrine hormones often affected by PAHs).

Mucal concentrations of 11-KT and VTG were determined and evaluated for effectiveness through comparative assays with blood plasma. This method was then applied to …

Effects Of Carboxylated Nanodiamonds On Macrophages During And After Differentiation, Maisoun E. Bani Hani

Biological Sciences Theses & Dissertations

Nanodiamonds (ND) are a carbon-based nanomaterial that are increasingly being proposed for developing novel imaging techniques, as carriers of biomolecules and therapeutic drugs, as coatings for implants, and for other biomedical applications. The exceptional chemical, mechanical, and optical properties of ND make this material suitable in a wide range of fields. The application of ND in the biomedical field is attractive but requires more in-depth investigation into the safety of ND and its interactions with different cells and systems. The effects of ND on the immune system are not fully understood or investigated and there are several controverting reports regarding …

Protective Effect Of Beta-Sitosterol Against Ethanol Toxemia, Dakota Cooper, April Boucher-Zamzo

Journal of Undergraduate Research at Minnesota State University, Mankato

Herbal medications have no indications of interactions with alcohol on their labels. There has been at least one clinical finding that saw palmetto with active ingredient beta-sitosterol used for enlarged male prostates caused pancreatic damage. This study with 20 male mice hypothesized that ethanol would increase the toxicity of beta-sitosterol. It was found that mice dosed by gavage with 0.1 ml of 95 proof ethanol died starting at the second dose and increased to 100% by the sixth dose (unexpected based on literature). 60-microgram injections of beta-sitosterol prevented deaths in 80% of the mice past the sixth dose opposite to …

Inhibition Of Post-Transcriptional Steps In Ribosome Biogenesis Confers Cytoprotection Against Chemotherapeutic Agents In A P53-Dependent Manner, Russell T Sapio, Anastasiya N Nezdyur, Matthew Krevetski, Leonid Anikin, Vincent J Manna, Natalie Minkovsky, Dimitri G Pestov

Rowan-Virtua School of Osteopathic Medicine Departmental Research

The p53-mediated nucleolar stress response associated with inhibition of ribosomal RNA transcription was previously shown to potentiate killing of tumor cells. Here, we asked whether targeting of ribosome biogenesis can be used as the basis for selective p53-dependent cytoprotection of nonmalignant cells. Temporary functional inactivation of the 60S ribosome assembly factor Bop1 in a 3T3 cell model markedly increased cell recovery after exposure to camptothecin or methotrexate. This was due, at least in part, to reversible pausing of the cell cycle preventing S phase associated DNA damage. Similar cytoprotective effects were observed after transient shRNA-mediated silencing of Rps19, but not …

Rxtx And Micromedex, Shawn Hendrikx, Kelly Hatch

Western Libraries Publications

No abstract provided.

Novel Insight Into The Liver-Lung Axis In Alcohol-Enhanced Acute Lung Injury., Lauren G. Poole

Electronic Theses and Dissertations

Background. Individuals who chronically abuse alcohol are almost 4 times more likely to develop Acute Respiratory Distress Syndrome (ARDS), the most severe form of Acute Lung Injury (ALI), but the mechanisms by which alcohol abuse sensitizes the lung to injury are poorly understood. However, the lung appears to share many parallel mechanisms of injury with the liver- a primary target of alcohol abuse. The overarching goal of this dissertation was therefore to expand on established mechanisms of alcohol-induced liver injury to ask innovative questions about mechanisms of alcohol-enhanced acute lung injury, as well as to develop new tools that may …

The Comparative Cytotoxicity And Genotoxicity Of Hexavalent Chromium In Humans And Sea Turtles., Rachel M. Speer

Electronic Theses and Dissertations

Monitoring the health effects of environmental contaminants can be achieved using sentinel species as models. Leatherback sea turtles (Dermochelys coriacea) are an endangered marine species that may experience prolonged exposures to environmental contaminants including hexavalent chromium [Cr(VI)]. While Cr(VI) has been identified as a known human carcinogen, the health effects in marine species are poorly understood. In this study the cytotoxic and genotoxic effects of particulate and soluble Cr(VI) were assessed in leatherback lung cells and compared to those in human lung cells. Cr(VI) induced a concentration-dependent increase in cytotoxicity and genotoxicity in leatherback lung cells indicating Cr(VI) …