Cell and Developmental Biology Commons^™

Modeling And Analysis Of Electric Signal In Neurons, Kevin J. Roberts

All Graduate Reports and Creative Projects, Fall 2023 to Present

Neurons in humans and other species transmit information by sending electric signals via axons. This process relies on the generation and propagation of action potentials—rapid changes in the membrane potential of the axon. Understanding the mechanisms of action potentials, including how they are generated and influenced by the axon geometry and material parameters, is crucial for gaining insight into neurological diseases such as Alzheimer’s and Multiple Sclerosis (diseases highly correlated to demyelination). In this work, we review and summarize mathematical models for signal transmission–including the classical Hodgkin-Huxley model, the Single Cable (SC) model, and the Double Cable (DC) model. We …

The Genetic And Environmental Determinants Of Stress Resilience Across Model Systems, Carson Len Stacy

Graduate Theses and Dissertations

Survival in fluctuating environments demands that organisms effectively anticipate and respond to future challenges. This capacity is shaped by both genetic background and environmental context. In this dissertation, I apply a population aware lens to explore how genetic diversity and environmental conditions intersect to shape stress survival. Integrating functional genomics and transcriptomics in Saccharomyces cerevisiae (brewer’s yeast) and a vertebrate (common canary) system, I dissect gene-by-environment (GE) interactions that underpin resilience. First, I move beyond a single reference genome by using a pan-genomic CRISPR knockout screen to assess osmotic stress survival across diverse S. cerevisiae isolates. This analysis reveals a …

Characterizing The Ethanol Sensitivity Of The Planar Cell Polarity Pathway In Endoderm Morphogenesis And Jaw Development., Raéden Omneil C. C. Rolle Gray

Electronic Theses and Dissertations

Fetal Alcohol Spectrum Disorders (FASD) describes a large range of developmental defects due to prenatal alcohol exposure. It is characterized by neural and facial defects, including jaw hypoplasia. Many factors contribute to the susceptibility of ethanol-induced facial defects, including genetics, yet the genes involved, and the cell events they regulate, are poorly understood. Zebrafish have a large number of tools for genetic manipulation available, share 70% of genes with humans, are fertilized externally and are translucent during embryogenesis, making them great models to study FASD. Previous studies show that two members of the Planar Cell Polarity (PCP) pathway, zebrafish vangl2 …

Host-Intrinsic Factors Determine Anti-Tumor Efficacy Of Exercise In Pancreatic Ductal Adenocarcinoma, Sumedha Pareek

Dissertations and Theses (Open Access)

Pancreatic Ductal Adenocarcinoma (PDAC) is the third leading cause of cancer-related deaths with a low 5-year relative survival rate of approximately 13.3% for all stages combined. We have previously shown that exercise can improve quality of life and enhance functional capacity among patients with PDAC. Exercise induces a variety of changes in the tumor microenvironment with beneficial effects in several tumor types. However, our understanding of the clinical effects of exercise and the mechanisms that mediate anti-tumor effects are limited in pancreatic cancer.

In this project, using C57BL/6 mice from Taconic Biosciences (Tac) and Jackson Laboratories (Jax), we established a …

Ontogenetic Analysis Of Parasaurolophus Braincases (Ornithischia, Hadrosauridae) From The Kaiparowits Formation (Upper Cretaceous) Of Utah, Usa: Comparing Juvenile And Adult Morphology, Amanda "Billie" C. Guerrero

Electronic Theses, Projects, and Dissertations

This study documents the ontogenetic development of the braincase in Parasaurolophus, a lambeosaurine hadrosaurid dinosaur known for its distinctive cranial crest. Whereas the crest has been extensively examined for its roles in communication and display, the braincase remains less understood, despite its structural and functional relationship with the crest. This research compares the braincase morphology of a juvenile specimen (RAM 14000, "Baby Joe"), a subadult specimen (RAM 17000), and an adult P. tubicen (NMMNH P-25100), to investigate how developmental changes influenced sensory systems, neurocranial architecture, and biomechanical adaptations across ontogeny.

Detailed morphological analysis reveals progressive changes from juvenile to …

A Persistent Homology Framework For Scrna-Seq: Assessing Clustering Robustness And Quantifying Preprocessing And Integration Effects On Topological Features., Jonah Daneshmand

Electronic Theses and Dissertations

As single-cell RNA sequencing (scRNA-seq) data expands, robust methods for integrating diverse datasets are critical. This dissertation applies Persistent Homology (PH), a technique from Topological Data Analysis (TDA), to a collection of scRNA-seq datasets spanning eight tissue types to quantify how data integration affects topological features and biological interpretability. We assessed global topological structure using Betti curves, Euler characteristics, and persistence landscapes across raw, normalized, and integrated data representations. Our analysis revealed a performance inversion: while conventional methods excelled on unintegrated data, high-granularity topological methods, particularly those sensitive to global data structure, became superior after integration. This suggests a synergy …

A Ralgef Inhibitor Suppresses Lung Cancer Stem Cell Development And Tumorigenesis., Raphael Ngozichi Suarez Jigo

Electronic Theses and Dissertations

The RALGEF family of proteins are direct downstream effectors of the RAS oncoprotein. RALGEFs act as guanine nucleotide exchange factors (GEFs) for downstream RAL proteins, thus tying RAS to the regulation of RAL. Genetic studies have demonstrated RAL proteins to be key drivers of RAS-driven transformation and metastasis. Furthermore, this pathway has been implicated in chemoresistance, exocyst-mediated transport, and the modulation of cancer stem cells. Previous work in our lab reported the activity of a novel pan-RALGEF inhibitor (C4-180) against RAS-driven pancreatic cancer models. Here we show the agent to be active against in vitro and in vivo models of …

Further Characterization Of The Fungal Effector Mvlg-01732 In Planta And Heterologous Expression Of Fungal Effectors In Different Smut Fungi., Joseph Paul Ham

Electronic Theses and Dissertations

Host-pathogen interactions in smut fungi are characterized by effector proteins and their role in infection. The goal of this work is to better understand these interactions by further characterizing an effector from Microbotryum lychnidis-dioicae and heterologously expressing this and other effectors in heterologous species to see if the range of these effectors can play a role in pathogenicity when expressed in distantly and closely related fungal species. These effectors have been attuned over time to their host plant but have homologous interactors in other plant species. In this study, Microbotryum lychnidis-dioicae, Sporisorium reilianum, and Ustilago maydis, were all used …

Context Dependent Regulation Of Dicer Function During Oocyte-To-Embryo Transition, Nick A. Newkirk

Dissertations and Theses (Open Access)

Over two decades ago, Dicer was discovered as the primary enzyme responsible for the generation of small RNAs known as the microRNAs (miRNAs) and short interfering RNAs (siRNAs). Spatiotemporal regulation of Dicer-dependent small-RNA biogenesis affects many aspects of biology, including aging, disease progression, fertility, and cancer. Interestingly, a distinct population of Dicer-dependent small RNAs, known as the endogenous siRNAs (endo-siRNAs), are uniquely abundant in the germ cells and gametes, and are critical for normal fertility. Despite their function regulating new life, the mechanisms controlling their biogenesis and subsequent germ cell functions remain poorly defined. Work to parse these mechanisms in …

A Molecular Mechanism Of Epithelial To Mesenchymal Transition (Emt): An Evidence Based Lesson Applying Molecular Biology Through The Lens Of Cancer, Sophie Hasson, Melissa Rowland-Goldsmith

Open Educational Resources

This lesson aims to strengthen students’ critical thinking and molecular biology data analysis skills as well as their understanding of concepts related to the hallmark of cancer: tissue invasion and metastasis. Students begin by learning about the invasion of cancer cells, Epithelial-Mesenchymal Transition (EMT), and an important protein involved in EMT: E-cadherin. They then apply molecular biology knowledge to analyze data from multiple papers to infer the relationship between Snail and E-cadherin in different types of cancers. Next, they continue to interpret data from many papers to determine that a repressor transcription factor is present during EMT in cancer cells …

Mitochondria-Mediated Epigenetic Transfer Between Chondrosarcoma And Wild-Type Cells, Caleb C. J. Wyckoff

Biomedical Sciences Theses & Dissertations

Glioblastoma (GB), acute myeloid leukemia (AML), chronic lymphocytic leukemia (CLL), cholangiocarcinoma, and chondrosarcoma (CS) cancers all contain mutations in the gene isocitrate dehydrogenase 2 (IDH2). The mutant IDH2 enzyme exhibits transformation of alpha-ketoglutarate (αKG) into the oncometabolite D-2-hydroxyglutarate (D2HG) in the mitochondria of these cancers. Mitochondrial-mediated transfer between cancer cells and recipient cells is a significant event that impacts the physiology of the receiving cell, specifically the epigenetic landscape. Previous experiments indicating increased DNA methylation in mesenchymal stem cells exposed to IDH1 or IDH2 conditioned medium underscore the potential role of D2HG to alter methylation states. Additionally, the presence of …

Characterization Of A New Domestic Feline Macrophage Cell Line To Study Molecular Mechanisms Of Feline Coronavirus, Adam Espinoza

Electronic Theses, Projects, and Dissertations

Feline Coronavirus (FCoV) is a veterinary pathogen common in domestic cats. FCoV is transmitted via the fecal-oral route, results in mild enteric symptoms, and is considered feline enteric coronavirus (FECV). During infection the virus may transition from infecting host enteric epithelial cells to infecting host macrophages, resulting in a lethal systemic disease, and the virus is now considered feline infectious peritonitis virus (FIPV). FIPV arises in an infected individual, is not shed in the feces, and is not transmitted from cat to cat. There is limited research defining the host molecular mechanisms driving FCoV lethal outcomes, with few feline cell …

Immunological Surveillance Against Cancer Across Mammals, Orsolya Vincze, Piotr Minias, Alexandre Corthay, Fernando Colchero, Jean-François Lemaître, Louise Maille, Tamás Malkócs, Justus Hagemann, Dalia A. Conde, Samuel Pavard, Antoine M. Dujon, Beata Ujvari, Frédéric Thomas, Amy M. Boddy, Carlo C. Maley, Damien Chevallier, Tuul Sepp, Thomas Pradeu, Mathieu Giraudeau

Presidential Fellows Articles and Research

Contrary to expectations based on their higher cell numbers, larger and longer-lived species do not face dramatically increased risk of cancer. This strongly suggests that evolution has fashioned natural cancer resistance mechanisms, yet our knowledge remains limited on what these mechanisms might be. The cancer immunological surveillance hypothesis, proposed by Burnet and Thomas in the 1950s, highlights immunity as a key factor determining species-specific cancer resistance. Here we address the original, evolutionary interpretation of this hypothesis by investigating the relationship between cancer mortality risk and markers of efficient antigen presentation. Our results show that the expansion of the MHC class …

The Differential Effects Of Camp Mobilizing Agents On Tgf-Β-Induced Extracellular Matrix In Human Lung-Derived Fibroblasts: Insights Into Therapeutic Targets For Lung Fibrosis, Sarah Orfanos, Brian T. Deeney, Gaoyuan Cao, Nikhil Karmacharya, Anjani Ravi, Cynthia J. Koziol-White, Qi Yang, Rennolds S. Ostrom, Reynold A. Panettieri Jr.

Pharmacy Faculty Articles and Research

Background

Injury-repair responses typically induce tissue or organ scarring. Generally, cAMP-mobilizing agents inhibit the activation of fibroblasts and deposition of extracellular matrix. Some but not all cAMP-mobilizing agents inhibit fibrosis. Evidence suggests that inhaled treprostinil, a prostacyclin (IP) analog, increases intracellular cAMP levels [cAMP]I, and slows the decline in pulmonary function in patients with idiopathic pulmonary fibrosis (IPF). However, the molecular mechanisms by which cAMP-mobilizing agents, including treprostinil, alter the expression of matrix proteins in human lung fibroblasts (HLF) remain unclear. Unlike other Gαs -coupled receptors, we posit that the antifibrotic properties of treprostinil are driven by cAMP-mobilizing-dependent and -independent …

Effects Of Photo-Oxidized Crude Oil On Gulf Killifish Early Life Stages, Charles Campbell

LSU Master's Theses

Photo-oxidation of spilled crude oil generates polar compounds that can heighten toxicity to marine fish embryos. We investigated the effects of photo-oxidized crude oil on early life stages of Gulf killifish (Fundulus grandis) by exposing embryos under flow-through conditions to water-accommodated fractions of four oil treatments: fresh oil unexposed to either sunlight or weathering referred to as dark control (DC), a UV-light oxidized whole oil (LT), the polar fraction extracted from LT (Pol) and the remnants after extracting the Pol from LT (NP). Oil loadings of 0.38–3.00 g oil/kg water were tested. Total PAH concentrations and chemical profiles …

Mathematical Model Of Ovarian Cancer Tumor Growth In Mice, Jessica A. Hoffman

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.

Balancing Stability And Complexity In Boolean Models Of Biological Networks, Venkata Sai Narayana Bavisetty

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.

Losing Focus In The Age Of Tik Tok: Clinical Evidence For Policy Action On Social Media Use, Megan Conefrey, Robert Griffin

SURE Journal: Science Undergraduate Research Experience Journal

No abstract provided.

Tracking Livestock Heart Rate & Location Using Long-Range Radio Networks. An Immediate Solution For Farms Without Reliable Wi-Fi, Dermott Harkin, Martin Bradley

SURE Journal: Science Undergraduate Research Experience Journal

No abstract provided.

Voices Matter: Tackling Accentism In Ireland. A Study Addressing Accent-Based Discrimination Awareness In Education, Sadhbh Reddington, Victoria Graham, Holly Jordan, Mairead Moriarty

SURE Journal: Science Undergraduate Research Experience Journal

No abstract provided.