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Analyzing Food Access: An Investigation of Food Insecurity amongst Latinos in Rural Nebraska
No full textBackground: Food insecurity is a public health issue in the United States, with disproportionately higher rates among Latino/Hispanic households. Rural communities face unique geographical, socioeconomic, and systemic barriers that often exacerbate food access disparities. Despite the growing Latino population in rural areas, particularly in Midwestern states like Nebraska, there remains a critical gap in comprehensive research that integrates both objective and subjective understandings of their food environments. Understanding these multifaceted influences is crucial for developing effective, culturally sensitive interventions.
Problem Statement: This dissertation aims to answer the central question: How does food access and food insecurity manifest amongst Latinos in rural Nebraska? This research addresses the need for a holistic understanding of the complex interplay between environmental characteristics, socioeconomic factors, and policy impacts on food security within this vulnerable population.
Methods: This dissertation comprises three interconnected studies. Chapter 3 develops a novel Food Insecurity Vulnerability Index (FIVI) using Principal Component Analysis of 2020 US Census data to spatially identify and quantify food insecurity vulnerability across Nebraska\u27s census tracts. Chapter 4 assesses the objective food environment in 28 rural stores across nine towns using the culturally adapted Latino Nutrition Environment Measures Survey in Stores (Latino NEMS-S), examining food availability, store features, and acceptance of federal benefits. Chapter 5 employs a qualitative phenomenological approach, utilizing participatory mapping and semi-structured interviews with 18 self-identifying Latinas in rural Nebraska, to explore their lived experiences and perceptions of food access in their towns.
Results: Chapter 3 revealed that higher FIVI scores were concentrated in tribal areas and urban census tracts with significant Hispanic/Latino and Black/African American populations, indicating greater vulnerability to experiencing food insecurity. Chapter 4 demonstrated that large chain and local grocery stores significantly outperformed ethnic stores in terms of overall healthy and culturally relevant food availability. However, ethnic stores offered a unique selection of cultural food items. A significant finding was that a store\u27s acceptance of SNAP benefits was a strong predictor of a higher Latino NEMS-S score. Chapter 5\u27s findings showed that 68.3% of participants were food insecure, highlighting key barriers such as limited access to health-specific foods, inadequate public transportation, high rural cost of living, the detrimental benefits cliff effect of assistance programs, and challenges related to immigration documentation status.
Conclusions: Food insecurity among rural Latinos in Nebraska is an issue driven by the complex relationships between environmental characteristics, socioeconomic factors, and systemic policies. The findings highlight the need for interventions that extend beyond simply increasing the number of food retailers in rural areas. Interdisciplinary efforts must focus on comprehensive economic development, equitable city planning, advocating for culturally relevant, healthy, and affordable food options, and reforming assistance program eligibility and education to dismantle systemic barriers and promote health equity for all
Evaluation of the Zanesville-Muskingum County Ohio’s Mosquito and Tick Disease Vector Control Program
Get PDFThis project aimed to evaluate the Zanesville – Muskingum County Health Department’s (ZMCHD) Vector Control Program based on performance measures, program indicators, and customer satisfaction. A secondary goal of the project is to evaluate and revise the existing policies and procedures of the program in regards specifically to the safety of the intern. Based on information from the Ohio Department of Health infectious disease dashboard, in the last 10 years (2014-2024) Muskingum County has reported 12 total cases of La Crosse virus, one case of West Nile Virus, and one case of Malaria (Ohio Department of Health, 2024a). ZMCHD has implemented a Vector Control program primarily focused on mosquito prevention for many years. Utilizing the ZMCHD’s modified framework, an evaluation of their Vector Control Program for the years 2021-2024 was conducted. Based on the results of the evaluation the following recommendations were suggested: expanding the program to other vectors, consistently reporting performance measures, increasing promotional efforts in smaller communities, marketing through locally produced infographics or videos when possible, and increasing mapping software use (GIS). Due to the increased incidence of Lyme Disease in the county, expanding vector control to include educational efforts and surveillance of ticks is strongly encouraged. Additionally, a Vector Control Safety Procedure document was developed for use for all staff that work within the Vector Control Program. These implementations have the potential to improve the program’s outcomes and ensure safe practices throughout the process
Folding Thermodynamics for the Incorporation of a Fourth Stem in DNA Junctions
Get PDFThe main goal of our research is to gain an understanding of the molecular forces involved in the folding of complex nucleic acid structures and to utilize this data for refining nearest-neighbor interactions. In this work, we used a combination of UV-temperature dependent spectroscopy and differential scanning calorimetry (DSC) techniques to determine complete thermodynamic profiles for the helix-coil transition of three- (3WJ) and four-way (4WJ) DNA (with dU instead of T) junctions. Specifically, we determine the melting behavior and overall thermodynamic profiles for the incorporation of a fourth stem-loop (with 2, 3, and 5 base pairs) in 3WJ to yield a 4WJ. Each junction unfolds with TMs that remain constant with increasing strand concentration, confirming their intramolecular formation. The folding of 3WJ is triphasic while all other junctions are biphasic. Table 1 shows that for each transition, the favorable free energy terms result from the characteristic compensation of favorable enthalpies (formation of base-pair stacks) and unfavorable entropies (ordering of the oligonucleotide strands and immobilization of cations and water molecules). Analysis of the DSC curves yielded unfolding free energies of 19.1 ± 1.5 kcal/mol and unfolding enthalpies of 131.1 ± 8.3 kcal/mol. These trends indicate that the inclusion of two base pairs (4WJ-2bp) is enough to form a stable stem in the four-way junction. Supported by Grant MCB-1912587 from the National Science Foundation.https://digitalcommons.unmc.edu/surp2025/1000/thumbnail.jp
Targeting Human Bromodomain Proteins for the Treatment of Medulloblastoma
No full textMedulloblastoma (MB) is a malignant pediatric brain tumor, where MYC overexpression is associated with poor prognosis and reduced survival. Directly targeting MYC remains difficult due to the lack of a druggable site. Targeting epigenetic readers such as BET bromodomain proteins, particularly BRD4, has emerged as a promising strategy. In MYC-driven MB, the BD1 and BD2 domains of BRD4 recognize acetylatedlysine residues, and the C-terminal motif recruits transcriptional machinery to promote MYC transcription. Most pan-BET inhibitors (iBET) bind equipotently to all bromodomains (BRD2/3/4/T), exhibiting no domain selectivity and dose-limiting toxicity. While these compounds highlight the therapeutic potential of iBETs, domain selectivity remains a challenge. We structurally characterized two ligands SRX3305, a BRD4 inhibitor exhibiting nanomolar-range affinity but lacked structural characterization, and MDP20, a structural analog of MDP5, a known iBET. We solved the crystal structure of a BRD4-BD2/SRX3305 complex, which reveals a ligand-induced conformational change within the acetyl-lysine binding pocket that could be leveraged to improve BD2 selectivity. Several Fluorescence Polarization-based probes have been developed to aid iBET drug discovery, but few have been characterized. To address this, we developed and characterized a fluorescent chemical probe based on structural insights from BRD4-BD2/SRX3305 complex. The probe demonstrated an affinity in the 2-25 µM range across BD1/BD2 of BRD2 and BRD4, with preference for BD1. To further assess the possible selectivity of these iBETs, we determined the crystal structure of the BRD2-BD2/SRX3305 complex along with MDP20 in complex with BRD2-BD2 and BRD4-BD2. These structural insights will guide the design of domain-selective iBET
Brightly Visualizing Pancreatic Cancer Margins in Orthotopic Mouse Models with an Anti-CA19-9 Antibody Conjugated to a Near-Infrared Fluorophore
Get PDFBackground/Purpose: The only potentially curative procedure for pancreatic cancer is R0 resection, which is difficult to achieve due to poorly defined tumor margins. In the present study, we used an anti-CA19-9 antibody conjugated to a near-infrared fluorophore in orthotopic mouse models to target and visualize pancreatic cancer. Methods: Orthotopic models of the human pancreatic cancer cell lines SW1990 and BxPC3 were established by implanting tumor fragments into the pancreas of athymic nude mice. Anti-CA19-9 and control IgG were conjugated with IRDye800CW. Mice received 50 µg of CA19-9-IRDye800CW or IgG-IRDye800CW via tail-vein injection and were imaged after 72 h. MIA PaCa-2, a CA19-9-negative cell line, was used in subcutaneous models to assess targeting specificity. Results: Using the LI-COR Pearl imaging system in the SW1990 model, the tumor-to-pancreas ratio (TPR) was 4.51 (±0.74), and the tumor to the liver ratio (TLR) was 3.05 (±0.60) with CA19-9-IRDye800CW, while the TPR was 1.67 (±0.16) and the TLR was 0.95 (±0.05) for the non-specific control IgG-IRDye800CW. Using a clinically available fluorescence laparoscope, CA19-9-1RDye800CW demonstrated a TPR of 2.34 (±0.44) and a TLR of 2.23 (±0.49), compared to 1.11 (±0.13) and 0.69 (±0.07), respectively, for IgG-IRDye800CW in the SW1990 orthotopic model. In the BxPC3 models, the TPR was 3.82 (±0.55) and the TLR was 4.13 (±0.77) for CA19-9-IRDye800CW compared to 2.40 (±0.31) and 1.49 (±0.23), respectively, for IgG-IRDye800CW. Conclusions: CA19-9-IRDye800CW provided specific in vivo targeting of two human pancreatic cancer cell lines in orthotopic nude mouse models with superior TPRs and TLRs compared to IgG-IRDye800CW. This tumor-specific fluorescent CA19-9 antibody is a promising clinical tool for improved visualization of pancreatic cancer
The Chlamydia trachomatis Inclusion Membrane as the Confluence between a Pathogen and Its Host
No full textChlamydia trachomatis is a Gram-negative, obligate intracellular bacterial pathogen of humans. It is the most common bacterial sexually transmitted infection. As an obligate intracellular pathogen, it grows within a eukaryotic host cell. Within the host cell, it resides within a membrane-derived vacuole known as the inclusion. The inclusion integrates itself within the host cell membrane transport system, selectively localizing eukaryotic proteins and lipids to the IM. The inclusion membrane (IM) functions as the interface between the bacteria and host cell. The bacteria actively modify the IM by inserting type III secretion effectors into the IM, known as Incs. Incs interact with various host cell proteins. The cytokine, IFN-γ, is known to induce tryptophan catabolism, thus depleting host cell tryptophan. Since C. trachomatis is a tryptophan auxotroph, the bacteria enter a persistence phenotype, in which they are viable but non-replicative. We hypothesized that C. trachomatis would maintain its usual recruitment of eukaryotic proteins and lipids to the IM during persistence. For the most part, the bacteria were still capable of recruiting host lipids and proteins to the IM during persistence. Inc protein expression during persistence depended on multiple factors, such as Inc tryptophan content, ability to be secreted, and stability on the IM. Separately, prior studies had demonstrated that a eukaryotic SNARE protein, VAMP3, transiently interacted with multiple Incs. We hypothesized that proper Inc protein expression would be necessary for localization of VAMP3 to the IM. To test this, we developed and characterized novel inducible CRISPRi strains to knock down transcription of the first Incs that interact with VAMP3, IncF and IncG. Using these strains, we showed that VAMP3 recruitment to the IM is a complex process, in some cases supporting the idea that these Incs are important for VAMP3 localization to the IM and in other cases suggesting that they are dispensable. Finally, we showed that IncF and IncG interact with one another on the IM, contextualizing Inc-Inc interactions to help understand the mechanisms behind VAMP3 recruitment to the IM
Food Insecurity’s Influence on Cardiovascular Disease Outcomes in Missouri
No full textThis report evaluates the relationship between food insecurity and cardiovascular outcomes in Missouri residents through a scoping literature review, including assessing variables that may be involved. While available studies have shown a relationship between food insecurity and cardiovascular outcomes, information specific to Missouri is limited. The overarching aim of this study is to explore the relationship between food insecurity and cardiovascular outcomes of Missouri residents. METHODS: A scoping literature review was conducted utilizing the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology. Studies included were published in the U.S. in the last 10 years and analyzed the relationship between food insecurity and cardiovascular disease outcomes. Data summaries from the CDC, Feeding America Inc, Missouri Dept. for Health and Human Services were also reviewed to gather available information on food insecurity and cardiovascular disease specific to Missouri residents. RESULTS: 293 studies were initially identified through two databases. After applying eligibility criteria, 38 studies remained. DISCUSSION: Most included studies identified a relationship between food insecurity and cardiovascular disease, but no published studies were found assessing the relationship specific to Missouri, which was identified as a need for future research. This paper concludes with a discussion of the findings in the literature for minimizing the impact of food insecurity on cardiovascular disease, considers the public health implications of this topic, and identifies future research opportunities
An Exploration of Substance Abuse by Healthcare Workers During the COVID-19 Pandemic: A Scoping Review
No full textObjective
This scoping review aims to identify available literature and research on substance abuse by healthcare workers (HCWs) during the COVID-19 pandemic to examine whether the stress of their duties during the pandemic exacerbated existing issues of substance abuse.
Methods
A literature search using PubMed and Google Scholar using Harzing Publish or Perish identified 100 relevant professionally-authored, peer-reviewed, English-language academic articles published between 2015 and 2025 on substance abuse by HCWs. Exclusions were done via a review of the abstract and then from the full text, reducing the number of articles to three from those three articles which generated an additional 15 articles of relevance to the subject.
Results
Themes identified include that substance abuse by HCWs being linked with an increased risk of self-harm and suicide, and that high levels of stress during the pandemic increased their rate of substance abuse. These themes suggest an increased risk of self-harm amongst HCWs arising from that stress and fueled in part by substance abuse.
Conclusion
This scoping review highlights the issue of substance abuse as a problem by stressed HCWs during the COVID-19 pandemic and beyond. By doing so, governments, hospitals, or other stakeholders may provide increased mental health support to reduce substance abuse by healthcare workers and to support them during a public health emergency.
Keywords Nurse, Healthcare workers, COVID, Stress, Coping, Physician, Drug, Alcohol, Substance Abus
RvD2 Mitigates TNFɑ-Induced Mitochondrial Reactive Oxygen Species through NRF2 Signaling in Placental Trophoblasts
Get PDFINTRODUCTION: Hypertensive disorders of pregnancy (HDP) are marked by elevated levels of TNFα, which increases reactive oxygen species (ROS) and disrupts metabolism of trophoblasts. Resolvin D2 (RvD2), an omega-3 fatty acid-derived lipid mediator, is known to resolve inflammation, but its role in protecting trophoblasts by promoting antioxidant responses to alleviate ROS remains unclear. Nuclear translocation of nuclear factor erythroid 2-related factor 2 (NRF2) controls cellular defense mechanisms against oxidative stress and helps with the maintenance of cellular redox homeostasis. Upon translocation to nucleus, NRF2 activates the antioxidant response element (ARE), inducing the expression of genes that can mitigate ROS. Hence, we hypothesized that RvD2 activates NRF2 and prevents TNFα-induced mitochondrial dysfunction in trophoblasts.
METHODS: We investigated RvD2\u27s potential protective mechanisms against TNFα-induced oxidative stress in trophoblasts by pretreating JEG cells with 100 nM RvD2, followed by exposure to 50 or 100 ng/mL TNFα.
RESULTS: We also observed that placental TNFα levels were elevated, while NRF2 protein levels were reduced in human HDP placental tissues compared to normotensive placentas. We demonstrate that RvD2 alone enhances NRF2 nuclear translocation, increases glutathione levels and mitochondrial function, and reduces mitochondrial ROS. In contrast, TNFα alone decreases nuclear NRF2 levels, increases mitochondrial ROS and oxygen consumption rates, and impairs migration. Notably, pretreatment of RvD2 before TNFα exposure protects against mitochondrial ROS, increases NRF2 levels, and restores mitochondrial oxygen consumption rates in trophoblasts.
DISCUSSION: These findings demonstrate that RvD2 functions as a positive regulator of endogenous antioxidant properties by enhancing NRF2 levels and mitigating mitochondrial ROS in placental trophoblasts
Integrating Artificial Intelligence and Machine Learning with Causal Inference for Early Detection & Management of Cardiac Rejection
No full textCardiac rejection remains a challenge for heart transplantation patients, significantly impacting their outcomes. Traditional AI/ML approaches have demonstrated promising predictive performance but are often criticized for their “black-box” nature and lack of causal interpretability. In response, this dissertation presents a novel decision-support framework that integrates advanced AI/ML techniques with causal inference methodologies inspired by Judea Pearl’s ladder of causation.
Using a comprehensive dataset that combines clinical records from the UNMC heart failure registry, EPIC electronic health records, and UNOS transplant data, our approach includes gradient-boosted models enhanced with SHAP value interpretability alongside a structural causal model framework. This dual strategy facilitates the distinction between mere correlations and actionable causal relationships, enabling counterfactual reasoning and transparent decision-making. Expert clinical insights were incorporated throughout the modeling process, ensuring that the system reflects real-world practice and can be seamlessly integrated into patient care.
Key findings include the observation that, among patients categorized as low risk by our causal inference engine, none (0 out of 14) experienced cardiac rejection, a result that underscores the efficacy of causal modeling in risk stratification. This outcome not only validates the model’s predictive accuracy but also highlights the clinical value of understanding underlying causal mechanisms.
In conclusion, the integration of AI/ML with causality-driven methods provides a transparent and interpretable tool for early detection of cardiac rejection. This framework bridges the gap between predictive performance and clinical interpretability, offering a robust platform for personalized immunosuppressive management and ultimately, improved patient outcomes