Research Methods in Life Sciences Commons^™

Mechanical Characterization And Modeling Of Rat Myocardia Under The Influence Of Epirubicin, Abdallah Mahmoud Alkhaiyat

Theses and Dissertations

Cancer remains a predominant health challenge that is responsible for a significant portion of global morbidity and mortality. Epirubicin (EPI), a chemotherapeutic anti-cancer drug, has shown remarkable efficacy in combating various malignancies. However, it is known to have undesirable side effects on the heart, collectively referred to as cardiotoxicity. This research investigates the adverse effects of chemotherapy on cardiac contractility through an in vitro examination of the mechanics of healthy and infarcted animal heart tissues. Electrically stimulated slices of rat ventricular tissue were tested using an isometric force measurement tissue bath. The tissue slices were subjected to uniaxial stretching, allowing …

Caspases Protect Against Hyperglycemia Induced Necroptosis-Like Cell Death In Brain Endothelial Cells, Aleena S. Mathew

Theses and Dissertations

Acute diabetes characterized by high spikes in blood glucose levels in association with severe hyperglycemia can lead to an increased risk of ischemic stroke in the brain. To better understand high blood glucose levels, hyperglycemia, in the brain we explored its effects on endothelial cells. Endothelial cells line the inner walls of blood vessels and are directly impacted in hyperglycemia. Brain endothelial cells are a major component of the blood brain barrier (BBB) which tightly regulates the brain’s microenvironment. The type of cell death such as apoptosis, caspase dependent, or necroptosis, caspase independent, can exacerbate diabetes associated complications. There is …

Dynamic Mathematical Approaches To Understanding Pain In Sickle Cell Disease, Quindel Jones

Theses and Dissertations

In the last 50 years, pain in Sickle Cell Disease (SCD) has become more widely studied thanks to advancements in technology and awareness. Clinical studies, population surveys, pharmaceutical trials, and computational models have been created and conducted to elucidate the mechanisms, treatments, and prediction of Sickle Cell disease pain episodes. Computational models have become quite useful in unraveling disease pathology with the rise in data collection accessibility and advanced computational power. In particular, dynamic mathematical models have been used to investigate Sickle Cell disease pathology and treatment. In this work we conduct a literature review of mathematical models used in …

Investigating The Impact Of Chronic Inflammatory Pain On Ethanol Consumption In Mouse Models., Joshua L. Hunt

Theses and Dissertations

Chronic pain affects nearly 20% of Americans annually and for many alcohol provides a convenient and legally acquired palliative. Population-based studies have suggested a link between increased alcohol use and reduced pain, but chronic or excessive alcohol use potentiates the risk to develop alcohol dependence and neuropathy. However, sex differences in chronic pain and alcohol abuse are still not well understood. In the present study, we investigated whether chronic inflammatory pain using the inflammatory agent Complete Freund’s Adjuvant (CFA) model could alter ethanol consumption in male and female C57BL/6J mice. We observed that only CFA-treated male mice increased their ethanol …

Mild Traumatic Brain Injury In Yucatan Minipigs: Assessing Changes In Approachability And Mechanical Nociception Following Diffuse Central Fluid Percussion Injury, Mark D. Pavlichenko

Theses and Dissertations

Traumatic brain injury (TBI) is a major healthcare concern affecting millions. Symptoms of TBI include sensory sensitivity and social changes that may persist long-term. Due to similarities in cytoarchitecture, metabolism, and inflammation, higher order minipig models are advantageous for translational TBI research, however, there remains a shortage of information regarding their behavioral and sensory sequelae following injury. Therefore, in this study, we assessed changes in sociability and somatosensation in adult male and female Yucatan minipigs for up to one-week following a sham or central fluid percussion injury (cFPI). Specifically, the voluntary human approach task (VHAT) and the forced human approach …

Hypothalamic Manipulation Of The Anuran Hpg Axis: Alternative Hormones And A Non-Invasive Administration Route For Amphibian Assisted Reproductive Technologies (Art), Erin Michelle Saylor

Theses and Dissertations

Amidst the amphibian extinction crisis, in situ and ex situ amphibian species conservation initiatives utilize assisted reproductive technologies for optimal genetic management of captive and wild populations. Development of effective, simple, low-cost methods for obtaining gametes for artificial fertilization, sperm biobanking, or natural breeding alleviates obstacles for institutions or programs to apply reproductive technologies. Objectives herein include investigating the efficacy of alternative hormones for inducing spermiation, an alternative hormone administration route for inducing ovulation, exploring the physiological effects of hormone therapy, and utilizing sperm from deceased animals for biobanking.

Moisture Effects On Visible Near-Infrared And Mid-Infrared Soil Spectra And Strategies To Mitigate The Impact For Predictive Modeling, Francis Hettige Chamika Anuradha Silva

Theses and Dissertations

Instrumental disparities and soil moisture are two of the key limitations in implementing spectroscopic techniques in the field. This study sought to address these challenges through two objectives. The first objective was to assess Visible-near infrared (VisNIR) and mid-infrared (MIR) spectroscopic approaches and explore the feasibility of transferring calibration models between laboratory and portable spectrometers. The second objective addressed the challenge of soil moisture and its impact on spectra. The portable spectrometers demonstrated comparable performance to their laboratory-based counterparts in both regions. Spiking with extra-weight, was the most effective calibration transfer method eliminating disparities between instruments. The samples were rewetted …

Evaluation Of The Virulence Potential Of Avian Pathogenic Escherichia Coli Isolated From Broiler Breeders With Colibacillosis In Mississippi, Jiddu Joseph

Theses and Dissertations

Avian pathogenic Escherichia coli (APEC) is a bacterium that is responsible for colibacillosis in birds. However, information about broiler breeder APEC isolates is limited, but the data is critical due to the transfer of this bacteria down the production pyramid to progenies resulting in high mortality. Therefore, we evaluated the phenotypic virulence characteristics of 28 isolates using embryo lethality and day-old chick challenge assays. Also, the in vitro adhesion and invasion potential of selected nine isolates were identified. Results showed more than 1/3^rd of the isolates were highly virulent and the virulence increased as the number of virulence-associated genes …

Evaluating The Influence Of Concurrently Available Non-Drug Reinforcers On Drug Reinforcement Using Sophisticated Preclinical Models Of Substance Use Disorder, Madison M. Marcus

Theses and Dissertations

The maladaptive allocation of behavior towards cocaine and away from other concurrently available non-drug reinforcers (e.g., family, health, work, etc.) is a key characteristic of cocaine use disorder (CUD) that is embedded into multiple diagnostic criteria for CUD. Accordingly, basic research conducted in a drug-vs-food “choice” context has improved our fundamental knowledge of the behavioral and neurobiological mechanisms of drug reinforcement. However, to date, these preclinical studies have only been conducted with food as the alternative reinforcer. The extent to which other non-drug reinforcers compete with cocaine-taking behavior is unknown. The studies in this dissertation establish two sophisticated discrete-trial cocaine-vs-alternative …

Epithelial Membrane Protein 3 (Emp3b) Is A Novel Regulator Of Sympathetic Nervous System Development In Zebrafish., Jessica M. White

Theses and Dissertations

Notable progress has been made in understanding the development of the neural crest (NC). Neural crest cells (NCCs) can be divided into 4-5 subpopulations. A major lineage among trunk NC derivatives are sympathoadrenal (SA) cells, which give rise to the sympathetic nervous system (SNS). Trunk NCCs follow a ventromedial migration pathway where signals derived from the dorsal aorta instruct migrating NCCs to a SA cell fate. Defects in NC development can result in syndromes known as neurocristopathies. Neuroblastoma is one of the most common forms of pediatric cancer affecting nearly 800 infants each year in the United States (Takita et …

The Impact Of Hiv-1 Tat And Morphine On Spatial Distribution Of Drugs In The Brain., Austin M. Jones

Theses and Dissertations

Despite combination antiretroviral therapy effectively suppressing HIV within the periphery, the central nervous system (CNS) remains affected by the virus. Approximately half of people living with HIV will experience HIV-associated neurocognitive disorders (HAND) or neuroHIV. Concurrent opioid use exacerbates neuroHIV by promoting neuroinflammation, viral replication, and potentially altering the antiretroviral concentrations within the brain.

Using a transgenic mouse that expresses the HIV-1 Tat protein, we examined the effects of Tat and morphine on antiretroviral accumulation and distribution and the effects of Tat on morphine accumulation within the brain using infrared matrix-assisted laser desorption electrospray ionization with mass spectrometry imaging (IR-MALDESI-MSI). …

Behavioral And Physiological Effects Of Heavy Metals On Fish: A Review And Preliminary Results, Diana V. Morales

Theses and Dissertations

Pollution, specifically heavy metal pollution, in various bodies of water has been a significant issue for decades. Research has been conducted on heavy metals and their effects on the environment, larger fish species, and humans since the 1970s (Skidmore, 1964; Adeniyi et al., 2007; Adeosun et al., 2015; Bawuro et al., 2018). It is known that zinc is a neurotoxin in some species and causes harm to the environment. It is also known that it causes harm to people if it is ingested or if they are exposed to it for long periods of time (Mahurpawar, 2015; Mizuno and Kawahara, …

Pushing It To The Limit: Determining Asian Elephant (Elephas Maximus) Olfactory Sensitivity And Discrimination Through A Behavioral Choice Task, Matthew S. Rudolph

Theses and Dissertations

Elephants have shown remarkable olfactory capabilities. Their sense of smell impacts their foraging choices, behavior, and ultimately, survival. Being able to detect a target odor can allow elephants to locate specific resources, identify threats, and find receptive conspecifics. Previous studies have shown that elephants can consistently detect target odors, but have not identified the limits of this detection. Thus, to investigate the extent of elephants’ odor detection capabilities, we tested Asian elephants in a two-step odor discrimination task. First, we investigated whether elephants could detect odors at varying levels of dilution after a training procedure, and then whether they could …

The Art Of Amphibian Conservation: Linking In-Situ And Ex-Situ Populations Of Endangered Species Through Genome Banking, Isabella Joann Burger

Theses and Dissertations

Limited breeding success in captive breeding programs has necessitated the development of assisted reproductive technologies (ART) to preserve and increase genetic variation and population numbers of both captive and wild amphibian groups. ART has been shown to be successful in numerous anuran species, and current studies focus on the application of ART in ex-situ populations. The focus of this project is to show that linking in-situ and ex-situ amphibian populations through sperm cryopreservation, genome banking, and in-vitro fertilization is possible, with the goal of increasing gene diversity throughout groups in order to produce self-sustaining, wild populations in the future. Specific …

Identifying Genes Downstream Of Mef2 That Influence Ethanol Sedation In Drosophila Melanogaster, Ananya Talikoti

Theses and Dissertations

Alcohol use disorder is a global public health issue that affects millions across the world. It can result in negative physical and mental health outcomes, and currently treatment options are limited and rates of relapse are high. Identifying genes that affect aspects of ethanol behaviors in model organisms, such as Drosophila melanogaster, can serve to eventually develop more robust therapeutic interventions for those experiencing alcohol dependence. Previous studies have identified a relationship between a person's initial sensitivity to alcohol and their abuse potential for the drug in later life. Therefore, we can study sedation behaviors in Drosophila melanogaster to …

Variation In Personality Among Semi-Wild Myanmar Timber Elephants, Sateesh Venkatesh

Theses and Dissertations

This study examines two personality traits: exploration and neophobia, which could influence human-elephant conflicts. Thirty-one semi-wild elephants were tested over two trials using a custom novel puzzle tube containing three tasks and three rewards. Our studies show that elephants do vary significantly between individuals in both exploration and neophobia.

Genetic And Cellular Models For The Study Of Ptk2b And Adam10 In Adaptive Thermogenesis And Metabolism, Jared S. Farrar

Theses and Dissertations

In a cellular model, we demonstrate that the non-receptor protein tyrosine kinase 2 beta (PTK2B) plays a critical role in mouse cultured beige adipocyte differentiation. CRISPR/Cas9-mediated knock-out of Ptk2b results in non-differentiating white adipocytes and differentiated beige adipocytes with significantly reduced thermogenic gene and protein expression, enlarged lipid droplet size, and altered mitochondrial respiration. Together, these data in a cell culture system provide evidence for a role of PTK2B in the differentiation of mouse beige adipocytes.

In the process of developing a new mouse model utilizing the adipocyte selective Adipoq-Cre transgenic mouse, strong genetic linkage between a gene …

Focal Augmentation Of Somatostatin Interneuron Function And Subsequent Circuit Effects In Developmentally Malformed, Epileptogenic Cortex, Nicole Ekanem

Theses and Dissertations

Drug-resistant epilepsy (DRE) is a common clinical sequela of developmental cortical malformations such as polymicrogyria. Unfortunately, much remains unknown about the aberrant GABA-mediated circuit alterations that underlie DRE's onset and persistence in this context. To address this knowledge gap, we utilized the transcranial freeze lesion model in optogenetic mice lines (Somatostatin (SST)-Cre or Parvalbumin (PV)-Cre x floxed channelrhodopsin-2) to dissect features of the SST, PV, and pyramidal neuron microcircuit that are potentially associated with DRE. Investigations took place within developmental microgyria’s known pathological substrate, the adjoined and epileptogenic paramicrogyral region (PMR). As well, microcircuit relationships within the previously unexplored range …

Enhancing Chemosensitivity Of Lung Cancers By Manipulating The Tumor Microenvironment: Local Lung Delivery And Nanocarrier-Based Therapies, Hanming Zhang

Theses and Dissertations

Cancer is the second leading cause of death in United States causing an estimated six hundred thousand death in 2019. Among different types of cancer, lung cancer is the leading cause of cancer related death in both male and female. While targeted therapy and immunotherapy have shown promising clinical outcomes, currently there remain a significant proportion of patients who do not benefit from these strategies or who cannot tolerate them, making Pt based doublet chemotherapy still an indispensable component in almost all stages of treatment. However, partially due to the poor tumor distribution of small molecule drug, the development of …

Molecular Targets Of Psychedelics And Their Role In Behavioral Models Of Hallucinogenic Action, Hiba Z. Vohra

Theses and Dissertations

Psychedelics are a subset of hallucinogenic drugs that exert their characteristic effects through agonist activity at the serotonin receptor 2A (5-HT_2A). In this study, I aimed to characterize the modulatory role of the metabotropic glutamate subtype 2 receptor (mGluR2) in the 5-HT_2A-specific rodent model of hallucinogenic action, head-twitch response (HTR). Secondly, I aimed to explore if 5-HT_2A agonist-induced deficits in prepulse inhibition (PPI) of the startle response, an additional model of hallucinogenic action, could be produced in mice. Though 5-HT_2A agonist-induced PPI deficits, which represent interruptions in normal sensorimotor gating, have been described in …

Floral Symmetry Genes Elucidate The Development And Evolution Of Oil-Bee Pollinated Flowers Of Malpighiaceae And Krameriaceae, Farahnoz N. Khojayori

Theses and Dissertations

Specialization on insect and animal pollinators is thought to be the driving force for the evolution of floral traits. Specifically in the New World (NW), the oil-bee pollination syndrome has led to the convergence of floral characters in two distantly related families of core eudicots, Malpighiaceae and Krameriaceae. Both families display a flag-like structure that establishes a zygomorphic flower and floral oil rewards in epithelial elaiophores. These traits work concomitantly to attract and reward female oil-bees that help fertilize these flowers and in return receive oils. The underlying genetics of floral zygomorphy were studied in several clades of core eudicots, …

Does Genotype Correlate With Phenotype? Evaluating Ruffed Lemur (Varecia Spp.) Color Vision Using Subject Mediated Automatic Remote Testing Apparatus (Smarta), Raymond Vagell

Theses and Dissertations

Ruffed lemur (Varecia spp.) color vision research was conducted using a multidisciplinary approach: psychophysics, genetic analysis, technology, and animal training. The behavioral manifestation of Varecia spp. trichromacy was shown using a touchscreen apparatus (SMARTA). Trichromats performed better than dichromats when discriminating red from green (G₂ = 78.10, p < 0.001).

Zebrafish (Danio Rerio) As A Model For Orofacial Research, Kevin A. Ghaffari

Theses and Dissertations

Across species, the face and more specifically the mouth, serves as an essential facet of everyday life. Amongst humans the mouth serves as a tool for the ingestion of food, a marker for facial recognition and a medium for communication. In order for the mouth to properly form, a series of precise growth and fusion events are needed. In order to insure that these events are orchestrated properly is a wide array of signals, transcription factors and epigenetic regulators. Due to the needed precision of these events, congenital birth defects of the face such as cleft lip and cleft palate …