Digital Commons Network^™

Targeting The Dorsolateral Prefrontal Cortex With Transcranial Direct Current Stimulation To Improve Depression And Anxiety In Parkinson's Disease, Brock Renicks

Honors Theses

The aim of this study is to observe the outcomes of transcranial direct current stimulation (tDCS) as a treatment for Parkinson’s Disease (PD). This study will primarily look at changes in depression and anxiety, as these symptoms are often comorbid with Parkinson’s Disease. Transcranial direct current stimulation is a non-invasive, very low-intensity form of electrical stimulation of the brain. It is being increasingly used as a form of treatment for Parkinson’s Disease and depression and anxiety, however the literature is ambiguous, showing mixed results throughout various studies, with no standardization of tDCS administration. To determine the effect of tDCS on …

Evaluating Spect Neuroimaging In Psychiatric Diagnosis: A Critical Review And Proposed Randomized Controlled Study, Kiley Carter

Senior Honors Theses

Mental illness affects a substantial proportion of adults in the United States, yet psychiatric diagnosis remains subject to diagnostic variability. Single-photon emission computed tomography (SPECT) is a neuroimaging technique that measures cerebral blood flow and has been proposed as an adjunctive tool for psychiatric evaluation. Existing literature reports group-level perfusion patterns associated with certain psychiatric conditions, suggesting potential utility in diagnosing complex or treatment-resistant cases. However, critics of SPECT emphasize the absence of randomized controlled data demonstrating improved patient outcomes. To address this gap, a prospective randomized controlled trial comparing standard psychiatric care with SPECT-guided evaluation is proposed. The proposed …

Plasma Constituents Promote Endothelial Thromboinflammatory Dysfunction After Hemorrhagic Shock, Kelly E Sanders, Marissa D Pokharel, Baron K Osborn, Yao-Wei Wang, Charles E Wade, Lucy Z Kornblith, Mitchell J Cohen, Jessica C Cardenas

Faculty, Staff and Student Publications

Background: Hemorrhagic shock (HS) following traumatic injury is hallmarked by innate immune activation, hypercoagulability, and thromboinflammatory complications. To date, the direct link between HS, injury severity, and endothelial cell (EC) contributions to thromboinflammation remains poorly understood. The goals of this study were to determine the impact of injury severity and HS on endothelial-mediated thromboinflammation and examine whether these changes increase the propensity for thrombosis.

Methods: Plasma from 89 male trauma patients, stratified by HS and injury severity, and 10 healthy subjects were assessed for inflammatory mediators by BioPlex. Human lung microvascular endothelial cells were exposed to patient plasma for 4 …

Targeting The Dorsolateral Prefrontal Cortex With Transcranial Direct Current Stimulation To Improve Depression And Anxiety In Parkinson’S Disease, Brock Renicks

Poster Presentations

Around 40% of people with Parkinson’s Disease experience depression and anxiety (Zhao et al, 2025). Depression and Anxiety have been said to be localized to the dorsolateral prefrontal cortex (Brunoni et al, 2016). Transcranial Direct current stimulation (tDCS) has been shown to modulate depression and anxiety by targeting the dorsolateral prefrontal cortex (Sreeraj et al, 2023). It is beneficial due to its cost, portability, and simplicity of use. Thus we will be assessing the efficacy of tDCS in reducing depression and anxiety in individuals with Parkinson’s Disease.

Modeling Structural Support To Facilitate Novel Treatments Of Degenerative Disc Disease, Jose Luis Calderon

Poster Presentations

Over 600 million people worldwide suffered from low back pain in 2020, with projections for 2050 being over 800 million [1]. Annual costs associated with low back pain total over 450 billion dollars in the US alone [2]. This research serves as a proof-of-concept for the use of structural supports to facilitate intervertebral disc healing. This treatment would involve the implementation of these supports along with existing injection treatments to promote regeneration. In both models, along with the combined model, the ability for these supports to alleviate intervertebral disc height loss is shown. This indicates that these supports would serve …

The Relationship Between Mc1r Gene Variants For Red Hair And Clinical Responses To Anesthesia, Analgesia, And Pain: A Systematic Review Of The Literature, Mary Clark Allen

The Eleanor Mann School of Nursing Undergraduate Honors Theses

Background: Genetic variations of the melanocortin-1 receptor (MC1R) are commonly associated with red hair and pale skin. Research has linked MC1R variants with alterations in anesthetic response, pain perception, opioid sensitivity, and pain-related fear. Existing literature presents inconclusive findings, highlighting the need for further investigation.

Purpose: This review aims to synthesize current evidence concerning the role of MC1R variants in altering physiologic responses.

Methods: A systematic literature review was conducted by accessing CINAHL, MEDLINE, and PubMed through the University of Arkansas Libraries OneSearch platform. After applying inclusion and exclusion criteria, a total of 20 peer-reviewed articles were extracted for review. …

Advances In Glp-1 Receptor Agonists Delivery Systems For Obesity And Diabetes, Mehrnaz Abbasi, Kai Sun, Kevin W Huggins, Braeden Heath, Hannah Deloit, Lauren Mcginness, Kate Mccamy

The Brown Foundation: Institute of Molecular Medicine

Obesity and diabetes are chronic metabolic diseases affecting millions worldwide. Current treatments, including lifestyle changes, medications, and surgery, face challenges like poor adherence and side effects. Glucagon-like peptide-1 receptor agonists (GLP-1RAs) are recommended innovative medications for these conditions, with studies showing significant clinical benefits. GLP-1RAs are traditionally delivered orally or via subcutaneous injections, but these methods have limitations, including low bioavailability, poor solubility, the need for high doses, gastrointestinal side effects, and frequent dosing requirements. Novel delivery technologies offer promising strategies to overcome these challenges and enhance therapeutic effectiveness. Recent advances in drug delivery technologies, including nanocarrier- and microcarrier-based systems, …

Dyadic Agreement In And Task Correlates To A Measurement Of Conversational Success, Samantha Budge

All Graduate Theses and Dissertations, Fall 2023 to Present

Successful conversation matters for social connection, wellbeing, and quality of life, but people do not always agree on whether a conversation was successful, even when they participated in the same interaction. Conversation is also commonly measured through task success, even though it’s unclear how task success correlates to how successful a conversation feels. This study examined how conversational success is experienced by different conversation partners and whether feeling successful in a conversation is related to how well a task is completed.

Participants took part in a structured conversational task and then rated their own conversational experience using a self-report questionnaire …

Utilizing Brain Computer Interfaces That Interact With A Virtual Keyboard, Skye Lilienthal

Honors Theses

A brain-computer interface (BCI) can allow someone to utilize electrical signals in their brain to complete tasks using a computer. BCIs can help people take advantage of technology to type without the need for a traditional keyboard setup. This paper used the OpenBCI Mark IV to test the effectiveness of non-invasive BCIs with dry electrodes within the OpenViBE P300 Speller. This paper shows how to use the P300 speller through a setup pipeline. Results indicate that electrode placement affects P300 accuracy and that areas related to visual processing improve accuracy, suggesting that P300 signals can be detected within OpenBCI Mark …

Novel Biomarker Discovery In Multiple Sclerosis, Manisha Gangasani

Honors Theses

Multiple Sclerosis (MS) is a chronic neuroinflammatory disorder affecting the brain, spinal cord, and optic nerve. Patients experience cognitive, motor, autonomic, and emotional symptoms that often overlap with other neurological conditions, making early diagnosis challenging. Current diagnostic criteria require evidence of lesions with dissemination in time and space. Racial disparities in MS outcomes are well documented, with Black individuals often exhibiting greater disease severity, higher relapse rates, and increased disability compared to White individuals. These differences likely reflect a combination of genetic, biological, environmental, and healthcare access factors, underscoring the need to improve early diagnosis and reduce inequities in care. …

Characterization Of Circulating Extracellular Proteome In Plasma Samples Of Triple-Negative Breast Cancer Patients, Brionna Wilson

Honors Theses

Extracellular vesicles (EVs) are membrane-bound vesicles secreted by cells in the body that play an important role in intercellular signaling, immune modulation, and transfer of biomolecules between cells. EV s reflect the physiological state of their cells of origin, so they are being explored as potential noninvasive biomarkers for cancer detection and monitoring. Triple-negative breast cancer (TNBC), an aggressive subtype lacking targeted therapies, is difficult to detect early and currently has no reliable prognostic biomarkers. This study aimed to quantify EV concentrations in the blood serum of TNBC patients (n=40) compared with cancer-free healthy controls (n=35) as well as determine …

Developing A Protocol For Non-Cellular Transplantation Of Donor Mitochondria Into Recipient Cells, Andrew Parton

Honors Theses

Tumor innervation has emerged as a critical feature of cancer progression, with increased nerve density correlating with enhanced aggressiveness, metastatic dissemination, and poor clinical outcome. However, the functional contribution of neurons to tumor biology remains incompletely defined. We recently identified the intercellular transfer of mitochondria from neurons to cancer cells as a mechanism that promotes tumor progression. We therefore hypothesized that disruption of this transfer could attenuate tumor aggressivity. To directly investigate this process, we developed an approach to isolate mitochondria from donor cells and transplant them into recipient cancer cells independently of canonical cell-cell interactions. Transferred mitochondria were tracked …

Dean's Research Newsletter, May 2026, Neil W. Schluger

SOM Dean's Research Newsletter

No abstract provided.

An Investigation Of The Roles Aging, Gender And Age-Related Hearing Loss Play In Emotional Prosody Recognition, Giavanna Yowell

Undergraduate Honors Thesis Collection

Emotional prosody recognition is crucial for social interactions but is influenced by aging, gender, and age-related hearing loss (Lambrecht et al., 2012; Oerlemans et al., 2014; Palermo et al., 2013). No past studies have looked at all of these factors collectively. To address this shortcoming, the current study explored the relationships between aging, hearing loss and gender differences in emotional prosody recognition. The ability to recognize emotions through facial expressions was also included as a comparative measure. One hundred fifteen individuals (42 men and 73 women), ages 50 and older (M = 60.39, SD = 8.12), completed a hearing handicap …

The Impact Of Glucose Exposure On Organic Cation Transporters (Oct) Function In A Corneal Epithelial Cell Line, David A. Garza

Theses & Dissertations

Organic cation transporters (OCT) facilitate the movement of neurochemicals and medications, contribute to the removal of cellular waste, and facilitate neuronal communication. Three subtypes of these high-capacity, low-affinity transporters (OCT1, OCT2, and OCT3) are differently expressed in peripheral tissues such as the liver, kidneys, as well as the central nervous system. OCTs are also expressed in ocular tissues. Chronic hyperglycemia is a complication commonly associated with diabetes that can lead to ocular diseases such as diabetic keratopathy, which affects the cornea. In this project, we expose immortalized human corneal epithelial cells (HCE-S) to various glucose concentrations to study their impact …

Prefrontal Engagement In Cognitive Flexibility Across Paradigms, Katarina Kalajzic

Honors Scholar Theses

Cognitive flexibility is an executive function that involves dynamically adapting behavior in the face of changing environmental circumstances to achieve a particular goal. Disrupted in numerous psychiatric disorders such as Alzheimer’s disease, schizophrenia, OCD, and depression, the neural correlates of cognitive flexibility are not well understood. However, the prefrontal cortex (PFC) is strongly implicated in executive function and attentional control processes. Thus, we sought to examine the neural circuitry involved in distinct cognitive flexibility tasks – the attentional set-shifting task and the probabilistic 2-armed bandit task. Through optogenetic suppression, we targeted pyramidal neurons of the rodent medial prefrontal cortex, an …

Validation Of A Real-Time Pcr Laboratory Developed Test For The Detection Of Pneumocystis Jirovecii In Bronchoalveolar Lavage Samples, Caitlyn Moon

Honors Scholar Theses

Pneumocystis jirovecii is an opportunistic, host-obligate fungal pathogen responsible for causing P. jirovecii pneumonia (PJP) in humans. PJP is treated with trimethoprim-sulfamethoxazole (TMP-SMX), a strong broad-spectrum antibiotic that carries risk of renal and hepatotoxicity. Therefore, rapid diagnosis or exclusion of PJP is crucial to ensure PJP-positive patients receive effective treatment and PJP-negative patients avoid unnecessary antibiotics. Unlike most microorganisms, P. jirovecii cannot be cultured, presenting complications for the typical methods of diagnosing fungal pathogens. Historically, the gold standard for diagnosis was direct microscopic examination with stains such as methenamine silver and calcofluor white, but this diagnostic technique requires highly skilled …

The Development Of A Crispr-Based Calibrated Functional Assay For Classifying Pathogenicity Of Msh2 And Msh6 Variants In Lynch Syndrome, Olivia N. Amodeo

Honors Scholar Theses

Lynch syndrome is a hereditary disease caused by the inheritance of a mismatch repair gene variant. Individuals with this condition are predisposed to cancer development, most commonly colorectal cancer. Current guidelines for variant classification are based on numerous evidence categories, including functional evidence. However, many novel clinical variants are not well characterized, and evidence is difficult to obtain if functional assays are not calibrated.

To address this, our lab created a calibrated functional assay that calculates an odds of pathogenicity score for MSH2 and MSH6 gene variants that can be used as evidence for classifying variants of uncertain significance. This …

Feasibility Of Assessing Dietary Patterns And Anxiety In College Students: A Pilot Study Using Nutrition Questionnaires, Gad-7, And Asq, Kylie Ford

Electronic Theses and Dissertations

Anxiety is highly prevalent among college students representing a significant public health concern. Research indicates that dietary patterns may influence mental health outcomes; however, the practicality of collecting comprehensive dietary and psychological data in college populations remains unclear. This pilot study assessed the feasibility of evaluating dietary patterns and anxiety using self-report instruments. Participants completed the Nutrition and Eating Habit questionnaire, the Generalized Anxiety Disorder-7 (GAD-7), and the Anxiety Sensitivity Questionnaire (ASQ). Although twenty-one students were recruited, survey completion rates were low, with only seven participants completing the nutrition questionnaire necessary to calculate the Dietary Inflammatory Index (DII). Descriptive analyses …

A High-Throughput Assay For Monitoring And Quantifying Amyloid-Β Accumulation And Clearance In Alzheimer's Disease Cell Models, Ajish Ariyath, Fraulein Denise Arigo, Anna Fyfe, W. M.A.D.Binosha Fernando, Ralph Martins, Prashant Bharadwaj

Research outputs 2022 to 2026

Amyloidogenic proteins, such as amyloid-β (Aβ), self-assemble into cross-β fibrils whose accumulation is central to Alzheimer's disease (AD). Measuring Aβ aggregation and clearance in living cells remains challenging using current cell-based assays, which are often low-throughput or not suited for real-time monitoring. This study aimed to (1) develop a robust, quantitative, and scalable fluorescence-based assay using Amytracker to monitor Aβ accumulation and clearance in an Aβ-producing neuronal cell model, and (2) validate its utility for mechanistic studies and therapeutic screening. We established a plate-based fluorescence assay using Amytracker in MC65 neuronal AD model expressing the Amyloid precursor protein C-terminal fragment …

Circulating Sphingomyelins Correlate With Plasma T-Tau In Cognitively Unimpaired Older Adults At Risk Of Developing Alzheimer's Disease, Tahmida Sharmin, James D. Doecke, Pratishtha Chatterjee, Steve Pedrini, Hamid R. Sohrabi, Nicholas J. Ashton, Henrik Zetterberg, Manohar L. Garg, Kaj Blennow, Ralph N. Martins

Research outputs 2022 to 2026

Alterations in plasma sphingomyelin (SM) levels have been reported in Alzheimer's disease (AD), pointing to disturbances in lipid metabolism that may contribute to disease pathogenesis. Neuronal damage in early AD triggers tau release into central and peripheral systems. Despite influence from peripheral contributions, alterations in plasma total-tau (T-tau) remain valuable in indicating AD-related neurodegeneration. Investigating relationships between SM metabolism and tau release during preclinical AD may uncover important biochemical processes and support advancing early non-invasive detection and treatment approaches. This cross-sectional study investigated cognitively unimpaired (CU) older adults from the KARVIAH cohort, grouped by cortical amyloid-β (Aβ) status through positron …

Maximal Motor Unit Firing Rates Decline With Amyotrophic Lateral Sclerosis Progression, Gabriel L. Fernandes, Lucas B.R. Orssatto, Matheus D. Pinto, Joao S. Henkin, Ehsan Shandiz, Pamela A. Mccombe, Robert D. Henderson, Gabriel S. Trajano

Research outputs 2022 to 2026

Objective: Amyotrophic lateral sclerosis (ALS) is characterised by progressive degeneration of upper and lower motor neurons and their motor units (MUs). MU loss is compensated by collateral sprouting and reinnervation of muscle fibres. There is limited information about the properties of these surviving MUs as these processes take place. High-density surface electromyography (HD-sEMG) decomposition enables non-invasive analysis of individual MU firing behaviour during maximal voluntary contractions and assess their changes with ALS progression. Methods: Thirty-nine individuals with ALS (24 men; mean age 63 ± 16 years) completed up to five visits (interval 20.0 ± 7.9 weeks). Tibialis anterior HD-sEMG recordings …

Use Of Electroencephalography To Evaluate Neural Correlates Of Attention In The Oddball Paradigm, Folsom J. Berry

Honors Theses

Electroencephalography (EEG) and Event-Related Potentials (ERP) are tools used to study and analyze cognitive processing. EEG measures neuroelectric brain activity from the scalp, while ERPs are time-locked averages that are used to isolate neural responses to stimuli. The P300 (P3) component (positive waveform elicited at 300 milliseconds (ms)) is the primary ERP component. This thesis project had two main objectives. The first objective was to develop conceptual and technical competency in EEG/ERP theory, data acquisition, and processing. The second objective was to implement the visual oddball paradigm through experimental demonstration. This experiment tested the hypothesis that infrequent target stimuli will …

Race To Mitigate Aortic Dissection: Exercise, Pde5a, And The Dissecting Aorta, Siddharth K Prakash

Faculty, Staff and Student Publications

No abstract provided.

Assessment Of Skin In Patients With Systemic Sclerosis Using High-Frequency Ultrasound And Shear Wave Elastography: A Comparative Study With Histology, Molecular, And Clinical Parameters, Ruhani Desai, Filemon Tan, Minghua Wu, Jeffery L Browning, Samuel Theodore, Meng Zhang, Brian Skaug, Harshdeep Singh Chawla, Manmohan Singh, Salavat Aglyamov, Kirill V Larin, Maureen Mayes, Shervin Assassi

Faculty, Staff and Student Publications

Objective: Ultrasound (US) has been proposed as a potential tool for assessing skin fibrosis in systemic sclerosis (SSc). However, a large-scale comparison of US-based assessment with histologic markers of skin fibrosis has not been reported. We evaluated US-based skin assessments for their face validity (differentiation between involved SSc and healthy control [HC] skin), construct validity (comparison to modified Rodnan skin score [mRSS]), and criterion validity (comparison to histologic and gene expression fibrosis markers).

Methods: Twenty HCs and 52 patients with SSc underwent clinical and US assessment followed by a forearm skin biopsy. Predefined areas were assessed on the finger, hand, …

Brief Report: Hepatitis B Vaccination Histories In Persons With Hiv Needing Revaccination, Minhee Kang, Triin Umbleja, Anchalee Avihingsanon, Sandra W Cardoso, Josphat Kosgei, Karen J Vigil, Ta Thi Dieu Ngan, Unoda Chakalisa, Stephanie Caruso, Kenneth E Sherman, Kristen M Marks

Faculty, Staff and Student Publications

Introduction: Past studies of hepatitis B vaccines in people with HIV (PWH) have shown mixed results about improving responses with increases in dose or dose frequency, leading to inconsistent guidelines and practice. We examined vaccine series completion and revaccinations in PWH lacking a seroprotective response.

Methods: Hepatitis B vaccination histories were evaluated as a retrospective study in 561 participants of A5379 trial (NCT04193189). Individuals in 41 sites in Africa, Asia, South America, and the United States qualified for the trial with antibody titers below the seroprotective level (< 10 mIU/mL) despite past hepatitis B vaccinations. The primary measure of interest was the number of vaccines in the past vaccination records.

Results: Of the 1098 trial candidates, 561 (51%) did not …

Quantitative Muscle Magnetic Resonance Imaging Demonstrates Resolution Of Muscle Edema In Refractory Dermatomyositis: A Post Hoc Analysis Of A Proof-Of-Concept Clinical Trial Of Tofacitinib, Mona Dabiri, Anshula Nallapati, Marwin Groener, Patrick Debs, Jemima Albayda, Eleni Tiniakou, Lisa Christopher-Stine, Laura Fayad, Julie J Paik

Faculty, Staff and Student Publications

Objective: To evaluate changes in muscle edema using short-tau inversion recovery (STIR) imaging and quantitative diffusion-weighted imaging (DWI) with apparent diffusion coefficient (ADC) mapping in patients with refractory dermatomyositis (DM) treated with tofacitinib.

Methods: This post hoc imaging analysis included patients from a 12-week, open-label trial of tofacitinib 11 mg daily in refractory DM. Bilateral thigh magnetic resonance imaging was obtained at baseline and week 12 using standardized STIR, T1-weighted, and DWI sequences. Muscle edema (ME) and fascial edema were assessed qualitatively on STIR imaging. ADC values were measured in muscles demonstrating baseline STIR hyperintensity using three nonoverlapping regions of …

Severe, Non-Apneic Respiratory Dysfunction And Hypoxia Following Generalized Convulsive Seizures, Haley E Pysick, Rup K Sainju, Roshni Nair, Deidre N Dragon, Eduardo Bravo, Laura Vilella, Xiaojin Li, Samden D Lhatoo, George B Richerson, Brian K Gehlbach

Faculty, Staff and Student Publications

Objective: Sudden unexpected death in epilepsy (SUDEP) is a devastating consequence of some generalized convulsive seizures (GCS). Recent work has focused on seizure related apnea as a biomarker of SUDEP risk, frequently without characterizing the adequacy of non-apneic ventilation or identifying other dysfunctional breathing patterns. We hypothesized that GCS frequently induce immediate, severe, non-apneic respiratory dysfunction that can induce critical hypoxia and bradycardia and sought to characterize breathing patterns after GCS.

Methods: Adult patients admitted to an epilepsy monitoring unit were studied. The effects of GCS on breathing and heart rate were analyzed using nasal pressure transducers, chest and abdominal …

Neurointerventional Advances In 2025, Amol Mehta, Sunil A Sheth, Ashutosh P Jadhav

Faculty, Staff and Student Publications

No abstract provided.

Optimized Ultrasound Imaging Of Phase-Change Nanodroplets, Charles R Dyall, Dmitry Nevozhay, Andy Liu, Trevor M Mitcham, George J Lu, Konstantin V Sokolov, Richard R Bouchard

Faculty, Staff and Student Publications

Phase-change nanodroplets (PCNDs) continue to generate significant research interest due to their potential to extravasate into tissue, to be targeted for molecular imaging and drug delivery, and to undergo an induced phase-change to "activated" microbubbles (MBs) for ultrasound (US) imaging. To accurately quantify molecular markers, however, one assumes a consistent proportion of PCNDs in a region of interest (ROI) are stably activated and imaged. Herein we present a framework for developing a diagnostic sequence that is optimized for PCND activation uniformity, contrast, and acquisition time. To develop this framework, activation was examined at three scales of increasing complexity: single, adjacent, …