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Anti-MAA Antibodies Increase Disease Severity in a Mouse Model of Inflammatory Bowel Disease
Get PDFhttps://digitalcommons.unmc.edu/emet_posters/1044/thumbnail.jp
Evaluating Medical Usage and Injury Prevalence at the 2024 College World Series
Get PDFLarge-scale events such as the College World Series (CWS) pose unique challenges for medical services due to high crowd density, prolonged event durations, and variable environmental conditions. This study aimed to assess the medical usage rate (MUR) and injury prevalence at the 2024 CWS to inform future event planning and emergency medical preparedness. A retrospective analysis was conducted using patient encounter data collected between June 14 and June 24, 2024. Data sources included Union Medical event services, which documented on-site treatments and dispositions, and Omaha Fire Department EMS records detailing prehospital care. The MUR was calculated as the number of patients treated per 10,000 attendees. A total of 361 medical encounters were recorded among 377,814 attendees, yielding an MUR of 9.55 per 10,000. The most common medical presentations included heat-related illnesses (47.4%), minor trauma (22.2%), and general medical complaints (16.9%). Alcohol- and drug-related incidents were notably low (1.1%), which may reflect underreporting or a genuinely low incidence. Daily MUR fluctuations suggested an influence of external factors such as weather conditions and game scheduling. These findings highlight the need for targeted preventative strategies, particularly for heat-related illnesses, and adaptable medical staffing to accommodate variable medical demand. Future research should evaluate year-to-year trends in MUR at the CWS and compare these findings with other major sporting events to optimize medical preparedness and emergency response strategies.https://digitalcommons.unmc.edu/emet_posters/1045/thumbnail.jp
A Replication Study- Frequent Social Media Use and Experiences with Bullying Victimization, Persistent Feelings of Sadness or Hopelessness, and Suicide Risk Among High School Students- Youth Risk Behavior Survey, United States (2023)
No full textThis replication study examines the association between frequent social media (SM) use and bullying victimization, persistent feelings of sadness or hopelessness, and suicide risk among U.S. young adults using data from the 2023 Youth Risk Behavior Survey. The study replicates the findings of Young et al. (2024), the first CDC report to incorporate SM into national adolescent behavioral surveillance. Using a weighted, cross-sectional sample of 15,203 students, the replication analysis estimated unadjusted and adjusted odds ratios for outcomes, controlling for age, sex, race/ethnicity, and sexual identity. 77% of students reported frequent SM use. It was significantly associated with higher odds of bullying (both at school and electronically), feelings of sadness or hopelessness, and suicidal ideation. The replication confirmed the original findings and validated the robustness of the associations despite differences in the output from SUDAAN and SAS analyses. These results highlight the need for mental health interventions and continued exploration into social media’s role and influence in adolescent mental well-being and suicide prevention
The Role of Cell Size and Proliferation in Intestinal Crypt Organization
No full textThe stem and Paneth cells in the intestinal crypt are arranged in a checkerboard-like pattern. The contact between stem cells and Paneth cells plays a critical role in the maintenance and function of the intestinal stem cell niche. However, the physical and molecular principles underlying the maintenance of the checkerboard pattern are mostly unknown. Previous studies indicate that discrepancies in cell size control epithelial organization. We find that the stem cells are approximately 3.5 times smaller than Paneth cells. This study will determine if cell size discrepancy in the intestinal crypt has a causal role in generating checkerboard order-like organization. To interrogate the role of cell size in intestinal organization, we developed a stem cell mouse model to knock out Tsc1, a negative regulator of the mTOR pathway, to increase stem cells size, reduce the discrepancy in cell size, and determine its effect on checkerboard organization in the crypt. Upon Tsc1 knockout in stem cells, there was a decrease in size discrepancy and an increase in proliferation, accompanied by disruption of crypt organization. Interestingly, adhesion proteins: E-cadherin, beta-catenin, F-actin, and Nectin 3 enrichment at the crypt cells’ junctions were largely homogeneous between different cell types, indicating that they are unlikely to contribute to crypt organization. Altogether, our studies find that differential cell size and proliferation between Paneth and stem cells are drivers of crypt organization
Assessment of Polymeric Chloroquine Formulations for Targeted Therapy of Ulcerative Colitis and Metastatic Colorectal Cancer
No full textEffective targeted drug delivery is a critical unmet need in the management of both ulcerative colitis and metastatic colorectal cancer, where conventional systemic therapies may be hindered by suboptimal efficacy and significant side effects. This thesis explores the development and preclinical assessment of polymeric chloroquine (PCQ)-based nanotherapeutics, leveraging stimuli-responsive designs for disease-specific delivery and action.
For ulcerative colitis, a reactive oxygen species (ROS)-responsive nanogel system was engineered to release PCQ, a macromolecular derivative of hydroxychloroquine, specifically in the inflamed areas within the colon. Nanogels with well-defined size and positive surface charge were synthesized via reversible fragmentation chain transfer (RAFT) polymerization using a thioketal dimethacrylate crosslinker. The nanogels demonstrated ROS-triggered disintegration, stability in gastrointestinal environments, and preferential accumulation in inflamed colon. In a Citrobacter rodentium (C.rodentium)-induced murine model of colitis, the PCQ nanogels conferred superior local therapeutic effects, including restoration of epithelial integrity, reduction in immune cell infiltration, and modulation of inflammatory signaling, while minimizing systemic toxicity compared to free hydroxychloroquine. Evaluation of nanogel variants further revealed that optimizing particle size and surface charge can fine-tune the balance between local and systemic immunomodulatory responses, underscoring the need for careful formulation design in targeted colitis therapy.
In parallel, this work addresses the challenge of peritoneal metastasis in colorectal cancer, a clinical scenario marked by poor prognosis and limited treatment options. A reduction-responsive PCQ-gemcitabine (PCQ-SS-GEM) conjugate was developed, employing disulfide linkages to achieve glutathione-triggered, tumor-selective release of gemcitabine. In an aggressive CT26-Luc murine peritoneal metastasis model, PCQ-SS-GEM displayed approximately 40-fold enhanced in vitro cytotoxicity versus 5-fluorouracil and achieved near-complete suppression of peritoneal tumor growth and ascites accumulation in vivo. Notably, animals treated with PCQ-SS-GEM exhibited a near absence of peritoneal metastases on histopathological evaluation, far outperforming reference chemotherapy and vehicle controls. These results highlight the advantages of stimulus-responsive polymeric carriers for maximizing efficacy and minimizing systemic adverse effects in cancer therapy.
Collectively, this body of work establishes PCQ-based, stimuli-responsive nanotherapeutics as versatile platforms for disease-targeted treatment in both ulcerative colitis and metastatic colorectal cancer. The findings support further development and translational studies of these next-generation, controlled-release polymeric drug systems, with the ultimate goal of improving local disease control and clinical outcomes in patients suffering from inflammatory and metastatic disease of the colon
Regulation of Chromatin Remodeling by the Post-HSA Domain of BRG1, a Subunit the BAF ATP-Dependent Chromatin Remodeling Complex
No full textThe ATP-dependent chromatin remodeler BAF complex regulates nucleosome positioning, chromatin accessibility, and tissue specific gene expression. Its catalytic subunit, BRG1, contains several regulatory domains including the post-HSA region, proposed to modulate ATPase activity. Multiple cancer-associated mutations map to these regulatory regions underscoring their importance, yet the precise role of the post-HSA region in chromatin remodeling remains poorly understood.
To investigate the function of the post-HSA domain, we ectopically expressed FLAG-tagged BRG1 with post-HSA deletion (Δpost-HSA BRG1) in mouse embryonic stem cells. Western blot analysis confirmed expression of the mutant protein. To determine the effects of mutant protein expression on chromatin structure over an induction time course, CUT&Tag mapping was performed targeting histone post translational modifications H3K27me3 and H2AK119ub, Ser5 phosphorylation of RNA polymerase II (RNAPII-S5P) representing paused RNAPII, and FLAG epitope to track mutant BRG1 occupancy. Spike-in calibration strategies were optimized using Drosophila S2 cells to ensure quantitative reproducibility.
Induction of Δpost-HSA BRG1 resulted in downregulation of transcriptionally repressive histone modifications genome wide. Interestingly, we observed a consistent but unexpected decrease in RNAPII-S5P occupancy at both active and repressive genes. These findings suggest that loss of the BRG1 post-HSA domain in BAF disrupts the regulation between chromatin structure and transcriptional machinery, potentially affecting the stability of promoter-proximally paused RNAPII. Experiments to directly measure effects on transcription initiation and elongations are underway.
Together, this study provides new insight into mechanisms regulating chromatin remodeling by the BAF complex and the roles of regulatory domains
Unheard Voices: Mental Health Outcomes of Yazidi Females in the Aftermath of the Genocide by ISIS: A Literature Review
No full textThis literature review examines mental health outcomes among Yazidi females who survived Islamic State of Iraq and Syria (ISIS) captivity during the 2014 genocide. Yezidis, one of the oldest communities of Mesopotamia (modern-day Iraq), have a distinct ethnoreligious identity that has made them the target of repeated persecution and genocides throughout their history (Kizilhan, 2018). In order to draw a complete picture of the survivors\u27 needs, it is essential first to understand the mental health impacts of the violence-related trauma. At the same time, the interpretation of mental health outcomes and their causes helps tailor culturally appropriate support services.
Searches were conducted in PsycINFO, Scopus, CINAHL, PubMed, and Google Scholar for English-language studies published between 2015 and 2025 that examined mental health outcomes among formerly enslaved Yazidi females. After screening 114 records against predefined criteria, 26 studies met the inclusion criteria.
Most of these studies were conducted in internally displaced persons (IDP) camps in northern Iraq, while fewer additional studies were administered among resettled refugees in Germany. Across studies, findings consistently indicated a severe burden of trauma-related symptoms, including PTSD, depression, anxiety, and somatic distress. A small number of intervention studies described culturally responsive psychosocial approaches that showed potential benefit. However, the absence of longitudinal research and limited age-specific analyses were the main gaps found in the literature.
Overall, the existing literature underscores the need for long-term, culturally grounded mental health services that can support effective recovery and reintegration for Yazidi survivors
Assessing and Addressing the Needs of Socially Vulnerable Populations to Enhance Community Emergency Preparedness and Resilience: A Mixed Methods Study
Get PDFBackground: A robust understanding of the needs of individuals and communities can help reduce the impact of a disaster, especially on those communities that already have associated health disparities. By strategically including these populations into mitigation, preparedness, response, and recovery planning, emergency management plans can be enhanced to be more inclusive and effective by identifying targeted resources during a crisis. Additionally, understanding and improving upon individual resiliency can potentially bolster a community’s resiliency level and reduce overall susceptibility to a disaster event, and expedite the recovery phase. Purpose: The purpose of this study is to assess the emergency needs and individual resiliency levels of socially vulnerable populations and determine how they can be addressed across the emergency management lifecycle. This approach aims to enhance the overall community’s emergency preparedness and resilience capacities by providing programmatic recommendations to improve emergency management practices and health equity in Sangamon County, Illinois. Methods: A convergent parallel mixed methods design was used, combining quantitative surveys and qualitative interviews to assess individual resilience and emergency preparedness needs. The Centers for Disease Prevention and Control’s Social Vulnerability Index (SVI) was utilized to identify the more socially vulnerable geographic regions in Sangamon County and to identify the study population and associated SVI characteristics. Results: The survey results indicated that a low percentage of households had adequate emergency plans and supplies, highlighting the need for better preparedness. Interviews revealed themes of personal resilience, the importance of family and community, trust in authority, the value of preparedness, and the need for accessible information and resources. Integrated results provided context to both the quantitative and qualitative findings, illustrating a desire from the study population for inclusion in emergency management planning and for shared responsibility with the health department.
Conclusion: Recommended programmatic enhancements to Sangamon County\u27s emergency management plan were identified for each of the four phases: mitigation, preparedness, response, and recovery to improve health equity and resilience. The implementation science framework, equity-focused implementation research (EquIR) was applied to the recommended enhancements to ensure the interventions prioritized the needs of the socially vulnerable. The use of EquIR provides a framework to ensure that emergency management enhancements are inclusive and effective for bolstering community resilience
Mucin-type O-glycans Protects Against Pancreatitis
No full textThe increasing global prevalence of pancreatitis, along with its potential to rapidly progress to severe forms and its strong association with pancreatic cancer, makes it essential to understand the mechanisms underlying its progression. Truncated mucin-type O-glycans Tn and STn antigens are linked to pancreatic cancer and have also been seen in premalignant lesions and human pancreatitis samples. However, their role in pancreatitis remains unclear. This study uses a cerulein-induced acute pancreatitis animal model to investigate the impact of shortened O-glycans on immune response, pancreatic inflammation, and metabolic changes.
The loss of the molecular chaperone Cosmc in the pancreas causes the expression of truncated O-glycans, which leads to sustained inflammation and delayed tissue repair in the pancreatitis mouse model. Cre CosmcKO mice showed prolonged acinar dedifferentiation, edema, and increased serum amylase compared to wild-type controls. Similarly, with an initial increase in proinflammatory CD86-expressing M1 macrophages and sustained levels of the M2 macrophage marker Ym1/2 on day 14, the pancreas of Cre CosmcKO mice showed enhanced macrophage infiltration, which can eventually result in continued acinar-to-ductal metaplasia and fibrosis. The phosphoproteome analysis of the pancreas samples showed higher levels of phosphorylated perilipin-1, which is associated with enhanced lipolysis and free fatty acids in the pancreas that can worsen the damage. These findings collectively demonstrate that by resulting in a sustained inflammatory and metabolic imbalance, aberrant O-glycosylation of proteins in the pancreas can delay pancreatic recovery after pancreatitis
The Role of Responsive Feeding in Childhood Development and Clinical Implications: A Comprehensive Literature Review
Get PDFResponsive feeding refers to caregiver-infant feeding interactions that encourage healthy eating behaviors and support the child’s autonomy by responding to their hunger and satiety cues. Responsive feeding supports healthy early childhood development, influencing self-regulation in eating behaviors and long-term health outcomes, particularly in obesity prevention. A comprehensive literature review was conducted to examine the impact of responsive feeding practices on childhood development in the United States and its clinical implications. The objectives were to explore the role of parental feeding practices in shaping childhood eating behaviors, understand the relationship between responsive feeding and obesity, and determine literature daps. Articles for this review were sourced from PubMed, Google Scholar, and Embase. Studies were included if they were: 1) published between 2005 and 2025; 2) included material involving responsive feeding practices and their impact on childhood weight status; 3) published in peer-reviewed journals; 4) focused on children under the age of 5; 5) were published in English; and 6) were conducted in a high-income country. In total, 25 peer-reviewed articles are included with 18 being within the USA and 7 being from other high-income countries. The randomized control trials and observational studies in the review found that parental education/implementation of responsive feeding techniques was associated with lower BMI z-scores and better weight outcomes. Non-responsive feeding behaviors were linked to poor self-regulation development and increased risk for excess weight gain. Caregiver responsiveness is important in fostering healthy dietary patterns and emphasize the need for further research on how responsive feeding influences long-term developmental outcomes of infants. This review aims to analyze the clinical importance of responsive feeding and inform pediatric providers to help combat adverse health outcomes associated with non-responsive feeding behaviors