Medical Sciences Commons^™

Phytochemical And In-Vitro Cytotoxic Analyses Of Flavonoid Species Isolated From Chromolaena Leivensis, Luke A. Bryant

Electronic Theses and Dissertations

As a leading cause of death worldwide, cancer and its treatments remain a primary source of interest among researchers. Modern studies are looking into bioselective cytotoxicity to create new chemotherapies that do not have the same harsh side effects as those we use today. Natural product research has a promising future for the development of such treatments. Specifically, polar flavonoids may be the key to a bioselective treatment. Such flavonoid species are native to plants, often within flower petals or within the body. A natural antioxidant, they are designed not to harm healthy cells. This study focuses on the plant …

Robustness Assessment Of Head And Neck Proton Therapy Plans Using Composite Synthetic Cts: A Preliminary Step Toward Ai Driven Anatomy Prediction Planning: A Retrospective Dosimetric Study., Ryan Michael Rodriguez

Masters Projects

Proton therapy is more commonly being utilized for head and neck cancer treatment due to its ability to reduce dose to the surrounding normal tissue. However, one of the biggest challenges in proton treatment is its sensitivity to changes in tissue density, often necessitating adaptive replanning. This study evaluated if incorporating additional synthetic CTs (sCT) datasets during robust optimization can create treatment plans that maintain target coverage and organ sparing despite anatomical changes better than the original nominal plan, thereby reducing the need for adaptive planning in head and neck proton treatment. Ten head and neck cancer patients who underwent …

Ai Integration In Radiotherapy Workflows: Emerging Trends And Best Practices, Vi T. Dinh

Radiologic Sciences

Purpose To synthesize current evidence on artificial intelligence (AI) integration in radiotherapy workflows, identify emerging application trends, and examine best practices for clinical implementation.

Method A structured literature review was conducted using PubMed, Scopus, and Google Scholar to identify peer-reviewed studies published between 2015 and 2025. Eligible studies evaluated AI applications in radiotherapy workflows, including segmentation, treatment planning, and clinical decision-making. Findings were synthesized using thematic analysis.

Results Three primary themes emerged: (a) AI-based segmentation improved contouring efficiency and reduced interobserver variability; (b) AI-assisted treatment planning enhanced dose prediction consistency and workflow reproducibility; and (c) workflow integration supported clinical decision-making …

Impact Of Music On Patient Comfort During Mr Scans: A Literature Review, He Yan

Radiologic Sciences

Purpose To investigate the influence of auditory stimuli on patient comfort levels during magnetic resonance (MR) imaging, with particular emphasis on indicators of distress, duration of patient positioning, and utilization of emergency signaling devices.

Method An integrative literature review was undertaken utilizing peer-reviewed research articles sourced from journals within the fields of radiology, music therapy, and clinical practice. A comprehensive search was conducted across databases such as PubMed, ScienceDirect, SpringerLink, and Oxford Academic employing keywords including MR anxiety, music therapy, and patient comfort.

Results The body of literature consistently indicated that auditory stimuli significantly mitigate patient anxiety and distress in …

Assault Vs. Assistance: Radiologic Technologist Decision-Making When Fall-Risk Patients Decline Assistance, Pamela O'Dowd

Radiologic Sciences

Purpose To explore how radiologic technologists experience and respond to situations involving fall-risk patients who decline assistance during imaging procedures.

Method A cross-sectional survey design was used to collect data from practicing radiologic technologists recruited through the American Society of Radiologic Technologists. Descriptive statistics, including frequencies and percentages, were analyzed using SPSS to summarize participant responses, and a thematic analysis was conducted on open-ended responses.

Results A total of 87 respondents completed the survey. Results indicated that encounters with fall-risk patients who refuse assistance are common in clinical imaging practice. Sixty-three (72.4%) technologists reported having experienced situations in which a …

Quality Improvement Initiative To Improve Adherence To Ob Hemorrhage Policy And Standardize Pitocin Administration During Cesarean Sections To Reduce Postpartum Hemorrhage Risk, Lauren R. Litz, Monica Blauser

Doctor of Nurse Anesthesia Practice (DNAP) Manuscripts

Postpartum hemorrhage remains a leading cause of maternal morbidity and mortality, and Pitocin administration is an important component of hemorrhage prevention and management during cesarean delivery. Variation in Pitocin timing, dosing, method of administration, and adherence to evidence-based recommendations may compromise patient safety and create barriers to standardized obstetric anesthesia care. The purpose of this Doctorate of Nurse Anesthesia Practice quality improvement project was to evaluate current anesthesia provider practices for Pitocin administration during cesarean delivery, compare observed practices with the California Maternal Quality Care Collaborative hemorrhage toolkit and Society for Obstetric Anesthesia and Perinatology Enhanced Recovery After Cesarean recommendations, …

Characterization Of Catechol-Type Siderophore(S) From P. Mosselii Cfml 90-83, Kemper R. Rasnake

Electronic Theses and Dissertations

Iron is essential for many biological processes, where it is used as a cofactor. Even though it is abundant in the Earth’s crust, it is in an insoluble form unavailable to microorganisms in the soil. To overcome this, bacteria produce siderophores, which are secondary metabolites that have a high affinity for iron. This allows bacterial cells to obtain insoluble iron that is essential for survival. Pseudomonas mosselii, a Gram negative bacterium, was isolated from soil. It was selected for further analysis as it was found to produce siderophore(s) under iron-limited conditions, which have not been characterized previously. Therefore, we aimed …

Ai-Driven Segmentation And Volumetric Response Modeling Of Liver Regions To Radiotherapy, Aashish Chandra Gupta

Dissertations and Theses (Open Access)

In liver-directed radiotherapy (RT), liver regions receiving higher doses typically undergo atrophy while contralateral/adjacent lower-dose regions may exhibit compensatory hypertrophy through regeneration of healthy tissue. Optimizing the RT plan to promote regional hypertrophy while minimizing the risk of developing atrophy has the potential to enhance post-RT liver function and long-term survivorship. However, current clinical practice largely relies on global liver dose-volume metrics during RT-planning, which may obscure favorable dose-response correlation and limit actionable guidance for clinicians. Therefore, we hypothesized that post-RT regional liver response is governed by a combination of region-specific dose-volume and patient clinical features, and that these responses …

Retrospective Comparison Of Prostate Vmat Boost Plans With Central Versus Offset Isocenter Placement, Carly Shefffield

Masters Projects

This retrospective study evaluated the effects of isocenter placement on dosimetric outcomes for sequential prostate boost planning using volumetric modulated arc therapy (VMAT). Ten patients previously treated with whole pelvis radiation therapy (WPRT) followed by a sequential boost were selected. For each patient, two VMAT boost plans were created using identical planning objectives and beam arrangements. One plan was optimized using the original WPRT isocenter, while the second plan had the isocenter placed at the center of the boost planning target volume (PTV). Target coverage, conformity, and organ-at-risk (OAR) dose metrics were compared between the two planning techniques. Both plans …

Kras-Independent Factors Drive Pi3k Signaling And Circumvent The Necessity Of Kras-Driven Pi3k Activation In Pdac, Lucas Christopher Bialousow

MUSC Theses and Dissertations

Pancreatic ductal adenocarcinoma (PDAC) has one of the lowest five-year survival rates among cancers and is characterized by near-ubiquitous occurrence of oncogenic KRAS mutations. Oncogenic KRAS activates several downstream pathways, including ERK 1/2 MAPK and PI3K, which are critical for PDAC. However, accumulating evidence suggests that PI3K activity can be maintained independent of oncogenic KRAS. The high prevalence of KRAS^G12R in PDAC challenges the prevailing model of KRAS-driven PI3K activation, as this mutant is defective in direct engagement with PI3Kα. These observations raise important questions regarding how PI3K signaling is sustained in PDAC. Here, we investigated KRAS-independent mechanisms that …

Extracellular Vesicle-Mediated Transfer Of Gsdme-Nt Pores As A Mechanism Of Inflammation Propagation, Bifeng Xiao

Master's Theses

Inflammasomes are multiprotein complexes that initiate inflammatory signaling through activation of caspase-1, cytokine maturation, and cleavage of Gasdermin D (GSDMD). Cleaved GSDMD forms membrane pores that contribute to cytokine release and pyroptotic cell death. Recent evidence suggests that extracellular vesicles (EVs) may facilitate the intercellular transfer of inflammatory mediators. This study investigated whether GSDMD N-terminal fragment (GSDMD-NT) associates with EV-enriched fractions and contributes to inflammation propagation. Doxycycline-inducible HeLa cells expressing FLAG-tagged GSDMD-NT were used to generate EV-enriched fractions. Western blot analysis detected GSDMD-NT-associated material within EV fractions, while EV marker analysis supported successful enrichment of EV-associated material. Exposure of recipient …

Assessing Hpv And Hpv Vaccine Awareness And Perception Amongst Undergraduate Students, Maura Hawkins

Honors Theses

Human Papillomavirus (HPV) is one of the most common sexually transmitted infections in the United States. Vaccination rates remain low among college-aged students despite an effective vaccine being available. This study investigates HPV and HPV vaccination-related knowledge, beliefs, and perceptions among undergraduate students to inform targeted intervention strategies. Participants included undergraduate students (n = 19) who attended one of three focus groups conducted in April 2025 at the University of South Alabama. Structured interview guides explored HPV knowledge, perceived risk and severity, attitudes towards vaccination, autonomy in health decision-making, trust in health information sources, and preferred educational strategies. Discussions were …

A Quality Improvement Approach To Reducing Chronic Obstructive Pulmonary Disease Readmissions, Florwisse Rubio

Doctor of Nursing Practice (DNP) Scholarly Project

Problem:

The problem identified at the project site is that care transitions for patients with COPD lack standardized discharge processes, leading to inconsistent education, limited follow-up, and poor coordination of care.

Aim of the Project:

The primary aim was to improve patient outcomes by reducing the 19.6% 30-day readmissions among older adults diagnosed with COPD at the selected project site by implementing a standardized discharge intervention over 12 weeks, measuring progress, and ensuring appropriate workflow. The initiative of this project sought to foster a sense of proper continuity of care through timely follow-up, interprofessional communication among patients and providers, and …

Impact Of Anatomical Changes On Treatment Plan Robustness: A Comparative Study Of Intensity Modulated Proton Therapy And Volumetric Modulated Arc Therapy In Head And Neck Cancer., Jennifer Croft

Masters Projects

Head and neck cancer patients often experience anatomical changes during radiation therapy, including weight loss and tumor regression. These changes can alter planned dose distribution and affect treatment accuracy. Based on the previous understanding, IMPT offers highly conformal dose delivery but is sensitive to the patient’s geometry changes and daily setup uncertainties, while VMAT may provide greater stability under these uncertainties. However, as of today, there is no quantitative analysis and comparison between the two modalities using real clinical data. The purpose of this study is to compare the robustness of IMPT and VMAT for head and neck cancer by …

The Role Of 14-3-3 Proteins In The Pro-Inflammatory Response Of Microglia And The Neuronal Stress Response To Trichloroethylene Exposure, William Stone

ETDs from 2020-2029

ABSTRACT This dissertation examines how 14-3-3 proteins, with a focus on the 14-3-3θ iso-form, regulate signaling pathways relevant to neurodegeneration. While tradition-ally described as molecular hubs that organize protein–protein interactions, our work reveals how 14-3-3 function is shaped by environmental insults, namely bac-terial and neurotoxicant exposures, and how its disruption contributes to disease-associated processes. Two complementary approaches were used, focusing on microglial inflammatory signaling and neuronal responses to an environmental neurotoxicant, to define a broader role for 14-3-3 proteins in disease associated pathways in the brain. Chapter I identifies 14-3-3 proteins as modulators of microglial activation. Disrup-tion of 14-3-3 interactions …

Anatomy And Function Of Vasopressin Receptor 1a-Expressing Neurons In The Limbic Thalamus, David Joseph Kahn

Theses and Dissertations

The vasopressin (Avp) system modulates social behavior through region-specific and sex-dependent mechanisms, yet the role of Avp receptor 1a (Avpr1a) signaling in the thalamus has remained largely unexplored. This dissertation examined the distribution and functional contributions of Avpr1a-expressing neurons across the mouse thalamus using a combination of genetic labeling, anatomical quantification, and chemogenetic manipulation. Mapping of Avpr1a-expressing neurons revealed a presence in most thalamic nuclei, with highest densities in the anterior thalamic nuclei and midline nuclei. Notably, Avpr1a-expressing neuron densities did not mirror previously described patterns of Avp innervation, and no sex differences in Avpr1a-expressing neuron density were observed. Chemogenetic …

The Role Of Mitochondrial And Lysosomal Damage In Neurotoxicity From Parkinson 'S-Related Environmental Exposures, Neda Ilieva

ETDs from 2020-2029

Parkinson's disease (PD) is a progressive motor neurodegenerative disorder with a predominantly idiopathic etiology. More recently, however, the contribution of exogenous risk factors such as environmental contaminants has become of interest. Some endogenous genetic risk factors have been well characterized, but the mechanisms by which exogenous insults, such as environmental contaminants, drive dopaminergic neurodegeneration remain incompletely understood. This dissertation will address how environmental contaminants converge on mitochondrial and lysosomal dysfunction to activate parallel neurotoxic signaling pathways, with a focus on the LRRK2 kinase and the cGAS-STING innate immune pathway. Chapter 2 demonstrates that pharmacological inhibition of LRRK2 kinase activity protects …

Differential Roles Of Moesin And Vasp In Β-Catenin-Associated Networks During Zebrafish Heart Regeneration, Allen Rutman

Undergraduate Theses, Capstones, and Recitals

With cardiovascular disease remaining as the leading cause of mortality worldwide, it is largely due to the limited regenerative capacity of the human heart. However, zebrafish (Danio rerio) can fully regenerate cardiac tissue following injury, providing a valuable model for studying the mechanisms of heart repair. To investigate these mechanisms, we used proteomics methods in the past. Proximity labeling is a technique that identifies proteins based on their physical proximity to a protein of interest. It can be applied in organisms and in living cells (Roux et al., 2012; Cho et al., 2020). We used proximity labeling to characterize protein …

Mapping The Neuroexposome: Integrative Analysis Of Dementia Risk Factors Through Multi-Omics And Environmental Profiling In The Egyptian Population., Mai Ahmed Saadzaghloul Othman

Theses and Dissertations

Background: Dementia represents one of the most pressing public health challenges of the twenty-first century, with the global burden projected to reach 153 million cases by 2050. Egypt, as the most populous Arab nation, faces a corresponding rise in age-related diseases, yet comprehensive data from low- and middle-income countries remain severely limited. The neuroexposome framework, integrating genetic susceptibility, environmental exposures, and metabolic alterations, offers a powerful strategy to characterize the complex interplay between internal and external risk factors for Alzheimer's disease (AD) and Alzheimer's disease Related Dementias (ADRD).

Objectives: This thesis aimed to: (1) examine the distribution of APOE alleles …

Determinants Of Corporal Punishment And Severe Physical Punishment In Egypt: A Mixed-Methods Analysis For Child Protection Policy, Marwa Moustafa Nassef

Theses and Dissertations

Corporal punishment (CP) and severe physical punishment (SPP) remain a major public health, child rights, and child protection policy concern. In Egypt, despite legislative reforms, survey-weighted analysis of the 2021 Egypt Family Health Survey (EFHS) 2021 (CAPMAS, 2022) reveals prevalence rates of 60.5% for CP and 27.4% for SPP among children aged 1–14 (author’s calculations using EFHS-2021, n=7623), yet evidence distinguishing the determinants of routine corporal punishment from escalation to severe physical punishment remains limited in low- and middle-income contexts. Guided by Bronfenbrenner’s ecological framework, this mixed-methods study identifies key drivers of CP and its escalation to SPP among Egyptian …

The Gut Microbiome, The Gut-Brain Axis, And College Student Well-Being, Idi Mckay

University Honors Theses

This literature review examines how diet, stress, environmental exposure, and food accessibility may influence college students' mental health and academic performance through the gut microbiome and the Gut-Brain Axis (GBA). Current microbiome research often focuses on early childhood development, clinical disease populations, or older adults, while overlooking college-age students who experience significant social, environmental, and biological transitions. College students frequently face food insecurity, irregular eating patterns, chronic stress, inconsistent sleep schedules, and reduced access to nutrient-dense foods, all of which may influence microbial diversity and overall gut health.

This thesis explores how modern campus environments and lifestyle factors may contribute …

Molecular And Histologic Studies Of The Amygdala And Reward Circuits In Rhesus Macaques (Macaca Mulatta) With Self-Injurious Behavior (Sib), Jackie Barua

Doctoral Dissertations

Self-injurious behavior (SIB), also known as non-suicidal self-injury (NSSI), is characterized by deliberate infliction of harming one’s own body tissues without committing suicide, and persists in a group of captive rhesus macaques despite an enhanced enrichment program and pharmacological intervention with diazepam. The aim of this dissertation was to identify the neurobiological underpinnings of SIB by combining RNA-seq guided transcriptomic discovery and targeted candidate gene validation with unbiased histological and imaging analysis. The secondary aim was to employ a complementary mouse model to investigate the endogenous opioid system in response to diazepam. The amygdala transcriptome of primates with SIB (n …

Activated Dorsomedial Hypothalamic Astrocytes Regulate Feeding Behavior, Bella M. Lisenby

Honors Projects

The dorsomedial hypothalamus (DMH) region of the brain has been shown to be important for anticipatory feeding activity and play a role in restricting excessive food intake. In obese animals that overconsume calories, astrocytes within the DMH exhibit intracellular signaling changes indicative of cellular activation. Because astrocytes are known to influence neuronal function, we hypothesize that activated astrocytes regulate behavior. In the current study, we use chemogenetics combined with stereotaxic surgery to assess the contribution of astrocyte activity in the DMH towards metabolic behaviors.

Fentanyl Mediated Distortions Of Phasic Dopamine Release Dynamics Encoding Natural Reward And Aversive Processing In The Mammalian Mesolimbic Circuit, Oliver P. Culver Iv

MUSC Theses and Dissertations

Mu opioid receptor (MOR) agonists are recognized to disinhibit tonic dopamine (DA) in the ventral striatum (VS), contributing to opioid addiction and euphoria. However, MOR agonists can also inhibit non-drug reward-seeking, and disrupt conditioned responding to aversive stimuli, a phenomenon not readily explained by tonic DA disinhibition. We hypothesized that this effect could be due in part to disruption of phasic DA responses to conditioned stimuli (CS) which critically shape and maintain behaviors during naturalistic reward and aversive processing. Because MOR effects on CS-evoked phasic DA are largely unexamined, we conducted in vivo fiber photometric recordings in water-deprived male and …

Neuroinflammation And Neuropathology In A Novel Tau, Amyloid-Beta And Alpha-Synuclein Co-Pathology Model, Jhodi Mickayla Webster

ETDs from 2020-2029

Neurodegenerative diseases including Alzheimer’s disease (AD) and Parkinson disease (PD) often present with overlapping proteinopathies rather than aggregated proteins in isolation. Amyloid-β (Aβ) and phosphorylated tau are found in a substantial proportion of idiopathic PD cases, while α-synuclein (α-syn) pathology is present in over half of AD cases. The presence of these co-pathologies is associated with accelerated cognitive decline and increase mortality in these patients. In parallel, neurodegenerative diseases are increasingly recognized as being shaped by interactions between central nervous system (CNS) pathology and the immune system. Despite this, most experimental animal models of neurodegenerative disease examine single pathologies in …

Parkinson’S Disease Phenotype Stratification Using Multiple Correspondence Analysis, Kelly Astudillo

Dissertations, Theses, and Capstone Projects

Parkinson’s disease (PD) is the second most common neurodegenerative disorder, with over 12 million people projected to be affected by 2040 (Dorsey et al., 2018). Deep phenotyping and stratification can provide useful information regarding PD pathogenesis and can aid in the  development of disease modifying therapies that aim to delay the progression or prevent the onset of neurodegeneration (Blandini et al., 2019; Smith & Schapira, 2022). Utilizing multivariate methods such as multiple correspondence analysis (MCA) permits for the simultaneous analysis of distinct data modalities. To the best of our knowledge, MCA has not been previously used to explore phenotype patterns …

From Transcriptome To Function: Multimodal Characterization Of Transcriptionally Defined Ventral Tegmental Area Dopamine Neurons, Natalie Dalton Fitzgerald

ETDs from 2020-2029

Substance use disorder is a complex neurobiological disease characterized by impaired control over drug taking and drug seeking. Drugs of abuse exert their reinforcing effects largely through dopaminergic (DAergic) projections from the ventral tegmental area (VTA) to the nucleus accumbens, where all drugs of abuse increase DA transmission. Beyond reward processing and reward learning, the VTA contributes to a range of psychiatric conditions, including schizophrenia and attention-related disorders. Although DA signaling has long been a major focus of addiction research, recent transcriptomic studies have revealed substantial heterogeneity of cell types within the VTA. Previous work from our lab identified two …

Investigating The Effects Of Increased O-Glcnaylation On Pathology In Alzheimer’S Disease, Melissa Louise Garcia

ETDs from 2020-2029

Alzheimer’s disease (AD) is currently the 7th leading cause of death, with few treatment options. It is known that AD pathology begins 20-30 years before clinical symptoms manifest. Some of the earliest pathological changes occur in glial cells of the hippocampus, causing them to become chronically reactive, as well as the accumulation of Amyloid-β (Aβ) in the hippocampus and hyperphosphorylated Tau (pTau) in the locus coeruleus, resulting in dysfunction of the noradrenergic (NA) system. Preclinical studies have shown promise in the abilities of the post-translational modification O-linked β-N-acetylglucosamine (O-GlcNAc). O-GlcNAc is a tightly regulated reversible enzymatic modification controlled by the …

Characterizing The Role Of The Paraventricular Nucleus Of The Thalamus D2r+ Neurons In Interoceptive Predictions, Briana Machen

ETDs from 2020-2029

Interoceptive predictions are internal models through which the brain anticipates future bodily states based on past experiences and environmental cues. Under healthy conditions, these predictions allow organisms to anticipate physiological needs and proactively adjust behavior to maintain homeostasis. When these processes become dysregulated, however, environmental cues can trigger maladaptive physiological responses. Although interoceptive prediction is increasingly recognized as a key mechanism underlying adaptive behavior, the neuronal circuits responsible for generating these predictions remain poorly understood. The paraventricular nucleus of the thalamus (PVT) receives convergent inputs from brain regions involved in processing both interoceptive signals and exteroceptive cues, positioning it to …

Vergence Task-Based Neural Pathways With Binocularly Normal Vision And Comorbid Persistent Post-Concussive Symptoms -Convergence Insufficiency, Ayushi Sangoi

Dissertations

Binocular dysfunctions are more prevalent in the persistent post-concussive symptoms (PPCS) population than in the general population. The most prevalent binocular disorder is convergence insufficiency (CI), affecting 3-17% of the general population and up to 10 times as many people with PPCS. CI makes it difficult to fuse or maintain fusion on targets at near, and its symptoms include double or blurry vision and headaches when performing close-range tasks such as reading, which can exacerbate PPCS symptoms. Given controversy over the subjectivity and effectiveness of diagnostic tools and symptom surveys for both PPCS and CI, understanding why CI has high …