Digital Commons Network^™

Phenotypic Analysis Of Murine Gut Associated Lymphocytes, Madison Flood

Master's Theses

γδ T cells are important in the role of immune homeostasis, especially in relation to the gut. It has been shown that there is a higher proportion of γδ T cells in the intestines than in circulation. With this knowledge, our lab focused on understanding the mechanisms of these cells, specifically regarding immune tolerance. In our preliminary research, we identified a subset of γδ T cells that express Foxp3, a transcription factor essential for the functioning of regulatory T cells, in the neonatal (5 day old) intestine. We hypothesized that these Foxp3+ γδ T cells have immunosuppressive functions upon exposure …

Bisacodyl Limits Chikungunya Virus In Vitro And Is Broadly Antiviral, Natalie June Lomascolo

Master's Theses

Identifying novel antivirals requires significant time and resource investment, and the continuous threat of viruses to human health necessitates commitment to antiviral identification and development. Developing antivirals requires years of research and validation, and recent outbreaks have highlighted the need for preparedness in counteracting pandemics. One way to facilitate development is to repurpose molecules already used clinically. By screening such compounds, we can accelerate antiviral development. Here, we screened compounds from the National Institutes of Health’s Developmental Therapeutic Program for activity against chikungunya virus, an alphavirus that is responsible for a significant outbreak in the Americas in 2013. Using this …

Investigating The Bactericidal Activity Of Lactobacillus Crispatus Cell-Free-Supernatant, Omar Majed Abdul-Rahim

Dissertations

Antimicrobial-resistant (AMR) microorganisms are an increasingly seriousproblem worldwide, accounting for thousands of fatalities annually. The current literature on combating AMR pathogens often centers on commensal microbes such as Lactobacillus species, which are most frequently found in asymptomatic ‘healthy’ patients and are believed to elicit protective effects. In this dissertation, I sought to investigate the protective effect of Lactobacillus crispatus, utilizing our vast collection of clinical isolates. Previous work from our lab had found that cell-free-supernatant (CFS) of L. crispatus is robustly bactericidal, and that this killing activity does not depend on hydrogen peroxide or lactic acid. We identified phenyl-lactic acid …

B Cells In The Gut Associated Lymphoid Tissue (Galt), Ameera Bukhari

Dissertations

The gut-associated lymphoid tissue (GALT) is the largest mass of lymphoid tissue in the body, and it is a unique line of defense where immune cells are in constant contact with gut commensals and pathogens. B lymphocytes constitute most of the lymphatic tissues of the gastrointestinal (GI) tract and they play a critical role in protecting from infections, promoting tolerance, and shaping microbiota in the gut through the production of immunoglobulins (Ig). Previous studies on GALT B cells in human showed that large B cell clones in the body partition into two broad networks: one includes the blood, bone marrow, …

The Role Of Glycogen Synthase Kinase 3 Β (Gsk-3Β) At The Cardiac Myofilament, Marisa Jean Stachowski

Dissertations

Altered kinase activity and localization is gaining appreciation as a mechanism contributing to cardiovascular disease. Previous work suggests that the kinase glycogen synthase kinase 3 β (GSK-3β) regulates contractile function of the myofilament, but this work was performed in vitro. The goal of this work was to investigate GSK-3β’s in vivo role in regulating myofilament function, the mechanisms involved, and the translational relevance in disease. GSK-3β’s myofilament localization was confirmed in wild type mouse and human tissue via western blot of myofilament enriched tissue and immunofluorescence. These experiments also revealed that GSK-3β phosphorylated at Y216 binds to the z-disc. We …

Elucidating The Function Of An Evolutionarily Conserved Col2Α1 Isoform During Vertebrate Development, Charles Lantz H. Ingersoll

Master's Theses

ABSTRACT

Formation of skeletal structural elements during vertebrate embryogenesis is largely a

conserved evolutionary process that employs numerous conserved genes and pathways. One

critical gene in this process is the highly conserved vertebrate Type II Collagen alpha 1 (col2α1).

It produces multiple splice isoforms that have different functions and expression patterns during

skeletogenesis. Two of the primary isoforms are of great interest; variant 1, the primary

embryonic isoform, and variant 2, a post embryonic isoform. While the more commonly known

post-embryonic isoform has been well studied over the last 30 years, identification of a unique

role for the evolutionarily conserved …

Development And Characterization Of A Tissue-Specific Reporter Line For Monitoring Circadian Clock Transcriptional Activity, Lilyan Mather

Master's Theses

Daily rhythms in physiology and behavior are produced by a circadian system consisting of a central clock located in the brain and peripheral clocks located in various peripheral tissues. Circadian clocks track time of day through the presence of a molecular clock that functions as a transcriptional-translational feedback loop. In the nucleus, the transcription factors CLOCK (CLK) and CYCLE (CYC) activate transcription of clock genes period (per) and timeless (tim). PER and TIM proteins slowly accumulate in the cytoplasm before entering the nucleus, where they inhibit CLK and CYC, and therefore repress their own transcription. Degradation of nuclear PER and …

Investigating The Role Of Nagc Reveals It To Be A Global Regulator, Natasha Peterson

Master's Theses

Bacterial colonization of host surfaces can result in symbiotic or pathogenic associations.As bacteria becomes more resistant to antibiotics, pathogenic bacterial colonization poses an increasing risk to human health. Symbiotic associations that have beneficial outcomes for both the host and the microbe can serve as models to investigate how bacterial processes affect colonization of host surfaces. The symbiotic relationship between the Gram-negative, bioluminescent bacterium Vibrio fischeri and the Hawaiian bobtail squid is one such model (E. V. Stabb & Visick, 2013). The study of this exclusive relationship has developed in a way where in vitro phenotypes can predict the ability of …

Comparison Of Feeding Functional Morphology Development In North American Esocids, Cheryl Theile

Master's Theses

Esocidae is a family of freshwater fishes within order Esociformes known for its long, cylindrical bodies, duck-bill snouts, and an impressive number of sharp teeth. There are four species, including two subspecies, in North America with areas of overlap of their geographic distribution. These ambush predators change diets from invertebrate prey to vertebrate prey during their first year of life, and the timing of this shift varies between species. In particular, the sister species Esox lucius (Northern Pike) and Esox masquinongy (Muskellunge) overlap in the upper Midwest, but E. masquinongy transitions to a vertebrate diet sooner in its development than …

Evolution Of Life-History Characteristics In Gadoidei, Joshua Hittie

Master's Theses

Life-history characteristics (e.g., age and growth) have been used extensively to understand the temporal population dynamics of fish species, but less so within a phylogenetic framework. This study investigates life-history characteristics within the suborder Gadoidei (order: Gadiformes) and to test the extent of phylogenetic signal for those characteristics. To accomplish this, a phylogeny of Gadoidei was first constructed based on both mitochondrial and nuclear genes. Within this phylogenetic framework, life-history traits, including growth rate, age at maturity, and longevity, as well as ecological data, such as water depth and diet type, were mapped to the phylogeny using parsimony analysis to …

Unveiling Bacterial Hitchhikers In The Urobiome, Genevieve Baddoo

Master's Theses

Microbial communities of bacteria, viruses, and fungi form complex interactions in nature. However, our understanding of these communities is limited to those that can be cultured in the lab. Enhanced culture methods have enabled the isolation of numerous fastidious species from urinary tract, definitively proving that the urinary tract of asymptomatic individuals is not sterile. In working with these isolates, our group has observed several instances in which a “purified” isolate actually harbors more than one species. We refer to these additional members as bacterial hitchhikers, a term previously used to describe similar occurrences in soil communities. I hypothesized that …

Dna Methylation Patterns Of Line-1 Elements Specific To Hc21p In Cancer Cells, Dametria Jetters

Master's Theses

Long Interspersed Nuclear Elements (LINEs) are retrotransposons. They function by making a cDNA copy, reverse-transcribing it into DNA and reinserting itself back into the genome; thereby, increasing its copy number. Sequencing of the human genome revealed that LINEs (L1) are underrepresented on the short arm of human chromosome 21 (HC21), but it is enriched in full-length copies. A number of previous studies have investigated the DNA methylation patterns of L1s in cancer cells, but these studies are typically done in euchromatic regions. The heterochromatic short arm of HC21 is primarily composed of heterochromatin. However these regions can be targeted for …

Rapid Radiation Of Zeiformes Revealed Through Comparison Of Jaw Morphologies, Jeffrey Peters

Master's Theses

Zeiformes (e.g., Dories, Lookdown dories, Tinselfishes, Oreos) are a deep (1000 m) to mid-water (100 m) marine order of acanthomorph fishes with a circumpolar distribution, and a fossil record extending back to the Late Cretaceous. The order consists of 33 species across six families. The phylogenetic placement of the Zeiformes within Teleostei has been debated, but more recent studies based on both molecular and morphological data place Zeiforms within Paracanthopterygii closely related to Gadiformes. Zeiformes are characterized by anal and dorsal profiles that contain a variable number of fin rays and spines. They are mostly deep bodied, highly compressed fishes …

Calcium-Mediated Induction Of Vibrio Fischeri Es114 Biofilms, Katia Elizabeth Semenchuk

Master's Theses

Vibrio fischeri bacteria form biofilms that facilitate symbiotic colonization of the Hawaiian bobtail squid, Euprymna scolopes. These host-associated biofilms require production of the SYP polysaccharide. However, it has been difficult to observe robust biofilm formation in vitro in a laboratory setting using wild-type strain ES114; instead, most work investigating syp-dependent biofilm formation has relied on genetically altered strains. Guided by recent findings that increasing calcium induces c-di-GMP (Tischler et al., 2021), a molecule known in other systems to promote biofilm formation, the question was posed as to whether high levels of calcium alone could promote syp-dependent biofilm formation by ES114. …

Biofilms On Plastic Litter: Community Composition And Activity And The Effects On Ecosystem Processes, Raul F. Lazcano

Master's Theses

The rapid increase of plastic production and disposal has resulted in plastic pollution becoming a global problem. In aquatic ecosystems, plastic litter is a substrate for biofilms, but little research has simultaneously assessed the effects of plastic litter on biofilm activity, community composition, and ecosystem processes. Our objectives were to: (1) measure biofilm activity and community composition on plastic litter relative to a natural surface in an urban river and (2) assess the impact of microplastic pollution on ecosystem metabolism and N2 flux in an oligotrophic lake. For objective (1) we incubated three common plastics with distinct physical and chemical …

Abl2 Promotes Alcohol-Associated Liver Disease Via Ppar Gamma Regulation, Gregory Malnassy

Dissertations

Alcohol-associated liver disease (AALD) is an umbrella term for a spectrum of diseases resulting from chronic alcohol (e.g. ethanol) abuse ranging in severity from reversible conditions such as alcohol-induced steatosis to advanced and largely irreversible liver pathologies including alcoholic steatohepatitis (ASH), alcoholic hepatitis (AH), fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). AALD is one of the primary causes of chronic liver disease worldwide and accounts for 44% of liver disease deaths in the United States. Drinking rates, both in the United States and globally, have increased year over year for the past three decades, a trend which has resulted in significantly …

Elucidating The Role Of Kmt2d In Her2+ Breast Cancer, Emily Ma

Dissertations

Breast cancer is the second leading cause of cancer-related deaths among women in the US. Histone modifications are common epigenetic changes that have been implicated in several breast cancers, including HER2+ breast cancers. Current therapies, such as trastuzumab, block the HER2 receptor to reduce tumor growth. Unfortunately, HER2+ breast cancers have found ways to overcome these therapies, leading to tumor resistance, metastases, and poor survival outcomes. A better understanding of the underlying mechanisms contributing to HER2+ breast cancer resistance may lead to the discovery of novel therapeutic strategies to improve patient outcomes.One prognostic marker for poor survival in women with …

The Identification Of Lxr-Dependent Pathways In The Dorsal Root Ganglia In Models Of Obesity, Nadia Elshareif

Master's Theses

Peripheral Neuropathy is characterized as injury to the peripheral nervous system. In terms of sensory neuropathy, metabolic syndrome is involved in chronic inflammation and ER stress pathways induced by lipid overload, leading to the structural and physiological damage of afferent sensory nerves. To protect the cell from lipid-induced ER stress, Liver X Receptors (LXRs) are sterol-activated nuclear transcription factors that are of particular interest due to its role in the regulation of lipid homeostasis, membrane phospholipids, and inflammation in metabolic tissues. Their role in the peripheral nervous system remains to be elucidated. LPCAT3, regulated by LXRs, has been shown to …

Characterizing A Novel Cocksackievirus B3 Protease Mutant And Its Response To Polyamine Depletion, Bridget Hulsebosch

Master's Theses

Enteroviruses, including Coxsackievirus B3 (CVB3), are pervasive pathogens that cause significant disease, including cardiomyopathies. Unfortunately, no treatments or vaccines are available for infected individuals. We identified the host polyamine pathway as a potential drug target, as inhibiting polyamine biosynthesis significantly reduces enterovirus replication in vitro and in vivo. Here, we show that CVB3 is sensitive to polyamine depletion through the polyamine analog diethylnorspermidine (DENSpm) which enhances polyamine catabolism through induction of polyamine acetylation. We demonstrate that CVB3 acquires resistance to DENSpm via mutation of the 2A protease, which enhances proteolytic activity in the presence of DENSpm. Resistance to DENSpm occurred …

The Utilization And Optimization Of Omics Trait Prediction Models Within And Across Diverse Populations, Ashley Mulford

Master's Theses

Most cancer chemotherapeutic agents are ineffective in a subset of patients; thus, it is important to consider the role of genetic variation in drug response. Lymphoblastoid cell lines (LCLs) derived from 1000 Genomes Project populations of diverse ancestries are a useful model for determining how genetic factors impact variation in cytotoxicity. In our study, LCLs from three 1000 Genomes Project populations of diverse ancestries were previously treated with increasing concentrations of eight chemotherapeutic drugs and cell growth inhibition was measured at each dose with half-maximal inhibitory concentration (IC50) or area under the dose-response curve (AUC) as our phenotype for each …

Assessing The Role Of The Interaction Between Polyamines And Heparan Sulfate In Coxsackievirus B3 Viral Infection, Oreoluwa Omoba

Master's Theses

Non-polioenteroviruses are highly infectious viruses that typically cause mild asymptomatic cases but can cause severe disease such as aseptic meningitis and dilated cardiomyopathy. Coxsackievirus B3 (CVB3) is a member of this group and is prevalent in the United States and Eastern Asia. Viruses like CVB3 rely on the host cell for many molecules in order to replicate. One such set of molecules is the polyamines. Polyamines are small, positively charged molecules that play a role in a multitude of cellular processes including RNA/DNA stabilization, gene expression, translation, and regulating membrane fluidity. Previous studies have shown CVB3 relies on polyamines for …

Population-Matched Transcriptome Prediction Increases Discovery And Replication Rate In Twas, Elyse Geoffroy

Master's Theses

Most genome-wide and transcriptome-wide association studies (GWAS, TWAS) focus on European populations; however, these results cannot always be accurately applied to non-European populations due to differences in genetic architecture. Using summary statistics from GWAS in the Population Architecture using Genomics and Epidemiology (PAGE) study, which comprises ~50,000 Hispanic/Latinos, African Americans, Asians, Native Hawaiians, and Native Americans, we perform transcriptome-wide association studies to determine gene-trait associations. Initially, we compared results using two transcriptome prediction models derived from the Multi-Ethnic Study of Atherosclerosis (MESA) populations: the African American (AFA) model and the Hispanic/Latino (HIS) model. We identified 141 unique genome-wide significant trait-associated …

Plasmodium Tlap-2 Is A Microtubule-Associated Protein With Microtubule Stabilization Properties, Grifin Berge

Master's Theses

Microtubules facilitate major cellular and morphological changes in eukaryotic cells, including the protozoan parasite Plasmodium. Microtubule-associated proteins (MAPs), only very few of which have been characterized in the malaria parasite, regulate the highly dynamic microtubules. Thioredoxin-like associated protein 2 (TLAP2) is a MAP unique to the phylum apicomplexa, which in addition to Plasmodium includes the important human pathogen Toxoplasma. Here we report on the cloning and microtubule-binding activity of TLAP2 of the rodent malaria parasite Plasmodium berghei (PbTLAP2). PbTLAP2 is coded by a single exon gene and consists of 598 amino acids. The protein contains a putative C-terminal microtubule-binding domain. …

Function Of Mllt3 In Liver Metabolism, Grace Ann Hammack

Master's Theses

The chromatin regulator MLLT3 recognizes target genes through the YEATS domain that identifies post-translationally modified histones, with preference for crotonyl and acetyl marks, and recruits different multiprotein effector complexes through its C-terminal domain to target genes. To study the role of MLLT3 in gene regulation, the Zeleznik-Le and Hemenway labs developed Mllt3 whole-body knockout (Mllt3;Rosa26-CreERT2) mice. These mice have a hematopoietic stem cell phenotype and an unexpected obesity and hepatic steatosis phenotype. It was unknown whether these phenotypes were from liver intrinsic effects or influenced by other parts of the body. To study this fatty liver phenotype further, Mllt3;Alb-Cre were …

Elucidating Regulatory Connections Between The Second Messenger Cyclic-Di-Gmp With Biofilm And Motility Phenotypes Of Vibrio Fischeri, Ali Razvi

Master's Theses

The symbiosis between the gram-negative marine bacterium Vibrio fischeri and its host Euprymna Scolopes occurs when the bacteria reaches and colonizes the light organ. This pathway to colonization begins in the outer marine environment and finishes within the deep crypts of the light organ, with states of biofilm formation and dispersal in between. This switch between biofilm formation to dispersal is important as the bacteria transitions from the surface on the light organ into a pore leading to the interior of the light organ. This dispersal is regulated by LAP system which is dependent on the second messenger c-di-GMP. Through …

Characterization Of Alcohol-Mediated Promotion Of Breast Cancer Stem Cells, Mckenna Below

Master's Theses

Breast cancer is the leading cause of cancer-related death in women globally, and one in eight women will be diagnosed with breast cancer at some point in her life. Alcohol consumption has been linked to increase breast cancer risk and increased risk of tumor recurrence. Understanding the molecular mechanisms of modifiable lifestyle factors such as alcohol consumption will help to lower these risks and design more effective therapeutic approaches. Estrogen Receptor positive (ER+) breast cancer comprises approximately 70% of all breast cancers, and these tumors are effectively targeted by endocrine therapy in the form of estrogen deprivation with aromatase inhibitors, …

Beta-Adrenergic Receptor Mediated Transcriptional Dysregulation In Hematopoeitc Stem And Progenitor Cells Leads To Bone Marrow Erythroid Suppresion In Multiple Myeloma Patients - Ex Vivo Investigations, Vimal Ravi Subramaniam

Master's Theses

The sympathetic nervous system (SNS) regulates our body’s involuntary response to stress or harm. Once activated, it releases hormones and neurotransmitters known as catecholamines throughout the body to mediate its recovery. The catecholamines bind to adrenergic receptors located on various cells in a process designated as adrenergic signaling to elicit this response. This process is not always to our benefit. Adverse symptoms such as anemia can result due to adrenergic signaling. Our laboratory previously showed that burn injury triggers adrenergic receptor stimulation resulting in anemia induced by diminished erythropoiesis. The development of anemia in these studies was found to be …

Characterizing A Putative Membrane Androgen Receptor In Glioma Cell Models, Emma Yuen

Master's Theses

The goal of this current research was to explore the role of a putative membraneandrogen receptor (AR) in modulating the viability of various models of glioma/astrocytoma, relative to normal (non-tumor) astrocytes. We hypothesized that binding to the membrane AR could enhance the sensitivity of glioma cells to toxic insult (i.e., the chemotherapeutic, Temozolomide, TMZ), while leaving “normal” astrocytes unscathed. Our data reveal that binding to the putative membrane AR sensitized C6 glioma cells to TMZ and the oxidative/metabolic insult, iodoacetic acid (IAA). And while there was some evidence that binding to the membrane AR could enhance the effect of TMZ …

Advancing Our Understanding Of Mechanosensitive Microtubule Acetylation In Neurons, Margaret Earl Utgaard

Master's Theses

Stiffness is a signaling cue in the brain, and neuronal response to stiffness impacts development, injury and disease. Mechanotransduction is the process of cells interpreting and converting mechanical cues to biochemical signals. Tubulin acetylation increases microtubule stability and could be mechanosensitive. The impact of stiffness on tubulin acetylation and role of septins is the focus of this project.It was hypothesized that stiffer surfaces would increase tubulin acetylation. SH-SY5Y cells were plated on varying stiffness and the ratio of acetylated to alpha tubulin was measured using immunocytochemistry. This study found SH-SY5Y cells had the highest acetylation on hard surfaces. SH-SY5Y cells …

Anthropogenic Particle (Including Microplastic And Microfiber) Transport And Retention In Streams Under Varied Environmental Conditions, Elizabeth Marjorie Berg

Master's Theses

Microplastics (plastic particles <5 mm) and other anthropogenic particles (i.e., synthetic, semi-synthetic and anthropogenically modified cellulose particles < 5mm) are pollutants of concern in aquatic ecosystems worldwide. Anthropogenic particles enter food chains, adsorb harmful chemical pollutants, and are ubiquitous in aquatic ecosystems. Streams are key sites of anthropogenic particle input, retention, and transport, and empirical measurements of particle movement in lotic ecosystems are needed to inform global budgets of anthropogenic particles and microplastics. However, factors that influence anthropogenic particle retention in lotic ecosystems are poorly understood. We demonstrate how environmental characteristics affect plastic transport and retention in streams in experimental and observational studies. In our experimental study, we used particle spiraling metrics to directly measure microplastic retention in outdoor, experimental streams at Notre Dame's Linked Experimental Ecosystem Facility (ND-LEEF). We tested the impact of stream discharge (i.e., high, low), benthic biofilms (i.e., well-established biofilms, reduced biofilms post-scouring), and benthic substrate type (i.e., cobble, pea gravel, sand, mixed substrate) on retention of microplastic fibers using pulsed releases and synchronized water sample collection at 3 sites downstream. We also collected benthic surface samples for biomass and microplastic density. Samples were filtered directly (water samples) or after peroxide digestion (benthic samples), and experimental microplastic fibers were enumerated visually using a dissecting microscope. Microplastic deposition rates were significantly higher with (1) higher discharge, (2) well established benthic biofilm (as opposed to bare substrate), and (3) larger and more homogeneous substrates. The observational study examined anthropogenic particles (including microplastics and microfibers) in the Milwaukee River during storm events. Lotic ecosystems are highly variable (e.g., seasonal changes, storm events), and most research assessing anthropogenic particle pollution extrapolates stream particle loads based on measurements during only one point in time. This limits the accuracy of anthropogenic particle and microplastic dynamics models in rivers, where frequent changes in discharge drives retention and transport of fine particles. In this study, we used automated samplers to collect water from the Milwaukee River during four distinct storm events in the spring and summer of 2018. We quantified anthropogenic particle abundance using standard methods and used nearby USGS gauges to determine discharge. Anthropogenic particle concentrations varied significantly among the four sampling periods, highlighting the temporal variability of anthropogenic particle transport across dates. When data from the sampling periods were pooled, there was a decrease in anthropogenic particle concentration in the water column after storm events, indicating that floods may "flush" microplastics from the river. Unexpectedly, anthropogenic particle concentrations were not correlated with other water quality metrics, including concentrations of total suspended solids, fecal coliform, chloride, nitrate, and sulfate, indicating that these metrics cannot be used to estimate microplastic concentrations and likely have distinct driving factors. These results provide novel insights into the environmental factors controlling anthropogenic particle and microplastic fate and are critical to understanding the role of lotic retention and transport in global plastic budgets.