Anatomy, Cell Biology & Physiology Department Theses and Dissertations
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Item The Role of TNF-Mediated Inflammation in Vascular Cognitive Impairment and Dementia(2026-05) Krick, Katelynn Elizabeth; Pierchala, Brian; Wilcock, Donna; Oblak, Adrian; Risacher, Shannon; Lasagna-Reeves, CristianOver 2.7 million Americans are estimated to be living with vascular dementia or mixed dementia with vascular components. Cerebral small vessel disease (cSVD) and cerebral amyloid angiopathy (CAA) are two common vascular pathologies that can lead to cognitive decline and dementia. In each of these progressive diseases, inflammation plays a strong role in response to disease onset and can become chronic, potentially contributing to neurodegeneration. TNF has dual roles, being important for homeostatic signaling at low levels but is strongly pro-inflammatory when expressed at high levels, orchestrating broad immune responses by inducing further cytokine release. TNF has been shown in our laboratory to be one of the earliest and most upregulated cytokines in both cSVD and CAA, making it an attractive therapeutic target in these vascular diseases. We hypothesize that TNF signaling is common between vascular diseases and may be an effective target for reducing vascular pathologies. Likewise, CAA has been identified as a risk factor for the development of amyloid related imaging abnormalities (ARIA) in individuals treated with amyloid targeting immunotherapies. ARIA consists of vascular side effects of edema and hemorrhage, which are often asymptomatic but in rare instances can be fatal when severe. Inflammation and TNF specifically have been associated with immunotherapy administration, supporting our hypothesis that TNF inhibition in a mouse model of ARIA will reduce hemorrhagic lesions and become an attractive combination therapy candidate with amyloid immunotherapy. In these studies, we identified longitudinal changes associated with amyloid deposition and CAA. Most notably, despite significant parenchymal amyloid deposition, CAA occurs at later ages (14-20months of age) in the Tg2576 mouse model, and this was associated with astrocyte activation markers surrounding the CAA-positive vessels and proinflammatory cytokines including TNF. We tested TNF inhibition in mouse models of cSVD, CAA, and ARIA. While we observed some modest effects of treatment in our model of cSVD, we observed minimal impact of TNF inhibition on ARIA events in response to amyloid-targeted immunotherapy when no significant CAA was present. Collectively, our data suggest that there are likely other TNF independent pathways that are important in vascular pathologies of dementia beyond TNF-mediated signaling.Item The Role of the Klotho KL1 Domain in CKD-Associated Cardiac Fibrosis(2026-05) Halim, Arvin; Lim, Kenneth; Moe, Sharon M.; Chen, Neal X.; Hato, TakashiCardiac fibrosis is a major contributor to cardiovascular morbidity and mortality in patients with advanced Chronic Kidney Disease (CKD). Cardiac fibrosis is associated with multiple adverse consequences, such as impaired cardiovascular functional capacity, diastolic dysfunction, arrhythmias, and sudden cardiac death. There are currently no clinically available direct therapies for cardiac fibrosis. Klotho is a pleiotropic protein that exhibits powerful cardioprotective effects. Klotho knockout models develop severe cardiac fibrosis, conversely Klotho replacement ameliorates this condition. Klotho can inhibit several pro-fibrotic pathways that are organized by lipid rafts, and this is independent of the phosphatonin, Fibroblast Growth Factor 23 (FGF23), which is elevated in CKD. KL1 is a fragment of Klotho that does not bind with FGF23 and may exert Klotho’s FGF23-independent cardioprotective effects with fewer off-target effects than Klotho. Therefore, KL1 is of significant therapeutic interest. However, to-date, no studies have investigated the role and mechanisms of KL1’s anti-fibrotic effects at the heart in CKD. The overall aim of my dissertation was to elucidate KL1’s anti-fibrotic role and mechanisms in CKD-associated cardiac fibrosis. My overarching hypothesis is that KL1 can directly inhibit CKD-associated cardiac fibrosis via the focal adhesion pathway. In Aim 1, I demonstrated that serum Klotho was associated with procollagen type 1 C-terminal peptide, a byproduct of fibrillogenesis, in a cohort of dialysis-dependent advanced CKD patients. In Aim 2, I developed a novel Klotho mass spectrometry assay to overcome limitations of current assays and simultaneously distinguish between Klotho isoforms. In Aim 3, using a progressive CKD rat model, I found that KL1 treatment reduced cardiac fibrosis and pro-fibrotic myofibroblast markers. Using human cardiac fibroblasts exposed to mineral stressors (i.e., high phosphate and calcium) found in CKD, I demonstrated that KL1 reduced collagen 1:3 ratio. In Aim 4, I found that KL1 reduced focal adhesion kinase (FAK) protein expression, in vitro, and trended to reduced cardiac FAK transcriptional expression, in vivo. I also found that KL1 colocalized to lipid rafts of human cardiac fibroblasts, in vitro. In summary, these findings suggest that KL1 can inhibit cardiac fibrosis in CKD via the focal adhesion pathway.Item Exploring Sources of First- and Second-Year Medical Student Perceptions of the Ideal Physician(2025-08) Kruskie, Megan E.; Deane, Andrew S.; Byram, Jessica N.; Organ, Jason M.; Hayes, Cleveland; Beckman, Emily S.Imposter phenomenon is linked to medical student burnout, which has significant implications for the physician workforce, patient care, and the healthcare system as a whole. One source of feeling like an imposter is comparing oneself to the expected image of an ideal physician, however, it is not well understood how physicians in training develop these ideals. In a sequential exploratory mixed methods study, Phase 1 conducted semi-structured focus groups (n=6) with first- and second-year medical students from Indiana University School of Medicine. Participants (n=22) were asked what attributes an ideal physician has, where these ideas came from, and if these expectations impacted their sense of belongingness in the field of medicine. Transcripts were analyzed using the framework method of thematic analysis. Participants in Phase 2 (n=131), who were from allopathic medical schools across the US, responded to a self-administered survey based on results of P1. Items on this survey included demographics, prior experiences in healthcare, habits/interactions with media, and the Clance Imposter Phenomenon Scale (CIPS). Descriptive statistics and chi-squared tests for independence were used to determine if there was an association between demographics and attributes or sources of the ideal physician. Hoeffding’s d correlations were used to examine correlations between television watching habits and CIPS. This study found two major themes with several subthemes: The Dynamic Ideal and Conceptualizing the Ideal. These themes describe how the ideal image of a physician is perceived by first- and second-year medical students. The statistical analyses found relatively few significant associations between variables; thus, the ideal physician depends on the individual lived experiences of medical students. This study demonstrated that while medical students do have preconceived ideas of what the ideal physician should be that stem from the sum of their lived experiences, there is no one-size-fits-all model. Educators can use these data to communicate with students who may be experiencing imposter feelings that these feelings are also a normal and expectable result of comparing oneself with an ideal type.Item Human Skeletal Remains at US Medical Schools: Provenance, Management, and Barriers to Ethical Stewardship(2025-06) Woods, Sabrina Christiane; Byram, Jessica N.; Agosto, Elizabeth R.; McNulty, Margaret A.; Organ, Jason M.; Mussell, Jason C.; Scheurich, James J.Following calls to action to ethically interact with human skeletal remains (HSR), the Task Force for Legacy Anatomical Collections within the American Association for Anatomy published guidelines on how to ethically manage HSR. Despite calls to action and recommendations, the literature lacks empirical investigation into the provenance of HSR and the current state of HSR management at US medical schools. Therefore, the purpose of this study was to investigate the provenance(s) of HSR at US medical schools, their current management, and barriers to improving management. To investigate provenance and current management of HSR, a questionnaire was nationally distributed via email to gross anatomy educators and lab managers identified through an internet search. Results were analyzed using descriptive statistics. To investigate the barriers experienced by faculty and staff in improving HSR management, 60-minute focus groups were conducted; data was analyzed using framework thematic analysis. The Theoretical Domains Framework was applied to the inductively interpreted themes. The results of this work show that provenance for HSR at US medical schools is largely undocumented and that the quality of HSR management varies by operational domain. For example, storage conditions and handling procedures are largely in line with professional recommendations at most medical schools. However, inventories and oversight committees are not active at over half of US medical schools and provenance investigations are not occurring at most US medical schools. Described barriers that hamper improvement of HSR management include ‘Social Influences’ and ‘Environmental Context and Resources’ from a lack of collegial and financial support as well as the management of HSR being a low ‘Goal’ for faculty and staff due to an overload of responsibilities. This work provides empirical evidence that most HSR at US medical schools are of unknown provenance and shows that there are relatively few aspects of HSR management where US medical schools currently excel. It also demonstrates barriers experienced by faculty and staff in improving the management of HSR and provides potential solutions to those barriers. Lastly, this work serves as a further call to action to show HSR the respect and dignity they deserve.Item Romidepsin is a Potential Therapeutic to Treat Metastatic Osteosarcoma(2024-12) Seiden, Emily Elizabeth; Greenfield, Ed; Byram, Jessica; Collier, Chris; McNulty, Margaret; Pollok, KarenOsteosarcoma is the most common primary malignant bone tumor in children, adolescents, and dogs. Lethality is due to lung metastases. Despite standard of care, patients with lung metastases have a survival rate of only 25%. Therefore, our lab studied potential therapeutics to target lung metastases. To do this, our lab repurposed already FDA-approved oncology drugs, which saves on the extensive time and cost of traditional drug discovery. Our lab also used 3-D spheroids (sarcospheres) that mimic in vivo tumors. In initial drug screens, our lab identified romidepsin, a histone deacetylase inhibitor, as a potent inhibitor of viability of highly metastatic osteosarcoma sarcospheres that was non-toxic to normal cells. Romidepsin was additive-to-synergistic with standardof- care chemotherapy and inhibited viability in a subset of patient-derived sarcospheres. This thesis therefore focused on determining the mechanism of action of romidepsin in osteosarcoma sarcospheres and the efficacy of romidepsin in a mouse model of metastatic osteosarcoma. Romidepsin either blocked growth or increased cell death in a growth phenotype dependent manner. Sarcospheres that grow slowly showed an increase in cell death, while those that grow quickly showed a cell cycle arrest. This trend differs in patient-derived sarcospheres. Though they grow slowly, only the most sensitive patient sample showed an increase in cell death. Our sarcosphere assay may be able to be used clinically to identify which patients are most likely to respond to specific drugs. In a tail vein injection mouse model of metastatic osteosarcoma, romidepsin increased survival and reduced respiratory distress in immunocompetent mice, but not in immunocompromised mice. This indicated that romidepsin may act on the immune system to have an effect. Therefore, it may be essential to use a mouse model with an intact immune system for romidepsin to decrease tumor burden. Overall, romidepsin is a potential therapeutic to treat a subset of metastatic osteosarcoma patients.Item What's My Role Again? Cultivating Interprofessionalism, Role Knowlege, and Role Clarity Through Case-Based Learning(2024-03) Herriott, Hannah Laine; McNulty, Margaret A.; Byram, Jessica N.; Agosto, Elizabeth R.; Deane, Andrew S.; Rebman, Rebecca; Scheurich, Jim J.As healthcare has shifted away from physician-centered practice, in favor of a patient-centered model, the importance of interprofessional team-based practice was recognized. Early exposure, practice working through clinical cases in teams, and learning each profession’s roles are essential determinants of successful interprofessional collaboration (IPC). Although interprofessional role comprehension is widely accepted as one of four core competencies of interprofessional education (IPE) and lack of role comprehension is associated with medical errors; literature measuring said construct is lacking. Role knowledge and clarity are two crucial skills that encompass identifying the roles and limitations of various professions’ scopes of practice and discerning which professional is best equipped to undertake a task in a particular situation. The present study investigated a novel IPE intervention employing role centered, small group casebased learning (CBL) sessions, integrated throughout an anatomy course for firstsemester occupational therapy (OTD), physical therapy (DPT), and physician assistant (MPAS) students. Additionally, fourth-year medical (MD) students participated in the IPE intervention by serving as near-peer facilitators for each of the small groups. A sequential explanatory, mixed methods design was employed to examine participants’: 1) acquisition of role knowledge, 2) demonstration of role clarity, 3) views of IPC after engaging in CBL sessions, and 4) perceptions of the intervention itself. The present study addressed the previously mentioned gap in the literature by exploring a CBL intervention’s influence on role comprehension (a previously unquantified aspect of IPE), in addition to their IPE-related perceptions. The aforementioned CBL intervention effectively improved role knowledge and clarity when implemented in-person; however, no significant changes were demonstrated in the virtual cohort. While many positive perceptions of the intervention and IPE experience were found, some misconceptions about professions and inhibitory power dynamics were also identified. Despite the latter findings, the CBL intervention examined in this study can serve as an effective model for cultivating IPE through enhanced role knowledge and clarity among health professional students.Item Identification of a Biofilm-Inducible Wound Macrophage Subset Characterized by Unique MARCO Expression: Significance in Chronic Wound Infection(2023-08) Das Ghatak, Piya; Roy, Sashwati; Gordillo, Gayle M.; Khanna, Savita; Xuan, YiStaphylococcus aureus (SA) biofilm infection, a common occurrence in human chronic wounds, exhibits sustained inflammation resulting in wound chronicity. Current studies claim that SA biofilm transforms host macrophages (m) towards an alternatively activated phenotype that suppresses the inflammatory response. Given a key role of m in wound healing, we investigate the phenotype and function of wound m (wm) in SA biofilm infection. To address the biofilm component of SA pathogenicity, two isogenic mutant strains of wild-type SA (USA300) were used that possess varying degrees of biofilm-forming ability. The strains, USA300::sarA (ΔsarA) and USA300::rexB (ΔrexB), have hypo- and hyper biofilm-forming ability, respectively. Mechanistic studies were performed on peripheral blood monocytes subjected to conditioned media (CM) derived from ΔsarA and ΔrexB biofilm cultures. scRNAseq and bulk RNAseq studies revealed presence of a unique m subtype that displays a distinct gene expression signature when exposed to CM derived from ΔrexB mutant as compared to CM from ΔsarA mutant. We identified macrophage receptors with collagenous structure (MARCO) as one of the highly abundant uniquely expressed biofilm-responsive genes in wm. MARCO, a member of the scavenger receptor, belongs to a larger group of pattern recognition receptors primarily involved in immunosurveillance and plays important roles in host defense and apoptotic cell clearance activities. scRNAseq and immunohistochemistry from human chronic biofilm-infected wounds demonstrated abundance of MARCO expression on wm. Significant upregulation of MARCO was observed in ΔrexB CM treated m in a dose and time-dependent manner as compared to ΔsarA CM treated m. Knockdown of biofilm-induced MARCO in m resulted in dysregulated m functions and inflammatory responses, suggesting its critical significance in biofilm infection. Immunohistochemistry studies in SA biofilm-infected porcine wounds validated the in vitro findings. In summary, this study identifies a SA biofilm inducible m receptor that has a significant role in wound chronicity.Item Identification of Extracellular Wnt Inhibitors for Novel Synergistic Anabolic Action on the Skeleton(2023-07) Choi, Roy Byung-Jun; Robling, Alexander; Bidwell, Joseph; Thompson, William; Pavalko, Fredrick; White, KennethThe Wnt pathway has been an obvious target for designing skeletal therapies, mainly based on the high-bone-mass phenotypes in patients with activating mutations in the Wnt co-receptors Lrp5 and Lrp6, or with inactivating mutations in the Lrp5/6 inhibitor Sost. An attractive property of the Wnt pathway is that it stimulates anabolic action in bone cells. The powerful anabolic potential of manipulating Wnt signaling in bone has been demonstrated by the recent FDA approval of sclerostin antibody (Scl-mAb) EvenityTM (Romosozumab) for the treatment of osteoporosis. However, an increased risk of cardiovascular events was reported, triggering the FDA to issue a ‘black box warning’ requirement for romosozumab. One potential solution to lower the risk of adverse events is to reduce the medication dose. Reducing the dose of Scl-mAb, while maintaining the anabolic potential of the drug, will likely provide a safer and more cost-effective strategy to harness Wnt for fracture prevention. Here, we found that dual inhibition of sclerostin and Dkk1 produced extremely potent synergistic bone anabolic effects in the cancellous compartment, using both genetic and pharmacological models. Further, much lower total doses of dual antibody treatment, given at optimized proportions, generated equivalent trabecular bone anabolic effects as Scl-mAb alone. On the contrary, we looked for other candidates that might potentiate the cortical effects of sclerostin inhibition. We found that either Sostdc1 or Notum deletion results in high bone mass, specifically in the cortical compartment, with little to no effect in the cancellous compartment. Inhibition/deletion of Sostdc1 or Notum alone had no detectable effects (Sostdc1) or mild (Notum) cortical effects, but suppression of either target while co-supressing/deleting Sost improved bone mass disproportionately. In summary, these findings highlight the potential therapeutic role that combinational inhibition of different Wnt inhibitors generates, resulting in synergistic bone anabolic action in different/select skeletal compartments.Item Metacognition in Anatomical Sciences Education(2023-06) Cale, Andrew Stephen; McNulty, Margaret A.; Byram, Jessica N.; Hoffman, Leslie A.; Longtin, Krista; Palmer, Megan; Williams, James C.Metacognition, the ability to self-regulate one’s learning and performance, is well-known to provide numerous academic and professional benefits for students, educators, and clinicians. However, few studies have studied metacognition specifically in the context of anatomical sciences education. Therefore, the overarching purpose of this dissertation was to explore the metacognition of students and educators who are learning and teaching the anatomical sciences. This dissertation investigated the metacognition of allied health students (physical therapy, physician assistant, and occupational therapy; n=109), first-year medical students (n=1802), and anatomy educators (faculty, associate instructors, and teaching assistants; n=13) in anatomy courses through three multiple-methods studies. Quantitative data were collected using assessment data and either the Metacognition Awareness Inventory (MAI), Practice-Based Learning and Improvement (PBLI) assignments, or Teacher Metacognition Inventory (TMI). These data were then analyzed using the appropriate descriptive and inferential statistics. Qualitative data were also collected through reflective writing activities (e.g., online discussion boards or reflective journals) and analyzed using thematic or framework analysis. Overall, both students and educators improved their metacognition across a semester of either learning or teaching anatomy, with certain subgroups demonstrating greater metacognitive ability or growth than others. Higher performing allied health and medical students were both more accurate at predicting their exam performances compared to their lower performing peers. Faculty also demonstrated the greatest teaching-specific metacognition, though teaching assistants exhibited the greatest growth in their teaching-specific metacognition. These improvements were primarily in their reflective ability and awareness of personal strengths and weaknesses as teachers. Several notable themes relating to metacognition were also identified such as student willingness to monitor learning diminishing over time due to competing academic or professional commitments. Additionally, novice educators were more inwardly-focused on personal traits and content mastery, whereas experienced educators were more outwardly-focused on interpersonal factors (e.g., student rapport and inclusive language). These insights into the metacognition of both students and educators can inform how to best support and improve teaching and learning in the anatomical sciences. Given the significance of metacognition, it may be beneficial to incorporate educational activities that can support the metacognition of both students and educators, simultaneously.Item Interactions Between Aging and Chronic Kidney Disease on the Skeleton(2023-05) Tippen, Samantha P.; Allen, Matthew R.; White, Kenneth E.; Moe, Sharon M.; Wallace, Joseph M.In the US, 15% of adults have chronic kidney disease (CKD). While CKD occurs across all ages, the prevalence is highest in the aged, with ~40% of individuals over age 65 having some form of CKD. CKD and aging are each independently associated with higher fracture risk, and thus overlaying CKD in the aging population presents an additive fracture risk. Cortical porosity is a central tenet underlying skeletal fragility and occurs in CKD and aging. Previous research on cortical porosity has focused on preventing pore formation, while research on pore reversal (infilling) is lacking. Pore infilling is dependent on proper osteoblast function, and previous research has shown that infilling is possible in young mice. However, it is unclear whether infilling is possible in aging mice due to aging-associated osteoblast dysfunction. Therefore, we proposed that aging animals with CKD may require both suppression of CKD-induced elevations in parathyroid hormone (PTH) and anabolic therapy to infill cortical pores. Romosozumab, a humanized monoclonal sclerostin antibody, uses PTH-independent mechanisms to increase osteoblast activity, making it an attractive therapeutic for CKD. CKD was induced by feeding aging (78-week) male mice 0.2% adenine for six weeks followed by two weeks of maintenance on control diet for a total study duration of eight weeks of CKD; mice were then treated with calcium water, romosozumab, or the combination and their effectiveness in improving skeletal quantity and quality was evaluated. Romosozumab treatment was associated with higher trabecular bone volume, lower cortical porosity, and higher mechanical properties compared to control animals. Combination treatment also resulted in benefits to trabecular bone volume and mechanical properties. These results demonstrate that both romosozumab alone and when combined with PTH suppression can be effective at improving bone microarchitecture and mechanical properties in aged individuals with CKD who are at high risk of fracture.