University Of Missouri-Columbia

NSF Awards · FY 2024 · 2024-07

This project aims to serve the national interest by significantly enhancing the spatial communication abilities of students on virtual field trips. Field trips are one of the most common methods used to deliver real life situated learning experiences to students. They represent a form of active learning, enriching traditional lessons by better engaging students and strengthening spatial, verbal, and math skills for many students. However, field trips also present major logistical, financial, and accessibility challenges for many educational institutions. In this IUSE level 3 project, Arizona State University in collaboration with the University of Missouri plans to engage in a 54-month project, the goal of which is to investigate the use of virtual field trips to improve student learning through a virtual field trip platform. The approach leverages web-based digital environments to deliver multi-user, synchronous, situated learning experiences offering students in-depth spatial communication practice. The project features a transformative change in the ways that spatial communication learning is conducted in STEM, democratizing it by making field trip experiences fully accessible anywhere, anytime. Broad dissemination of findings is assured through extensive faculty professional development and the implementation of iVisit in courses, workshops, webinars, and outreach. Intentional efforts will be made to reach low-income and students from groups underrepresented in STEM using iVisit, further improving STEM inclusion. Research questions posited to guide the investigations include (1) What learning affordances in virtual field trips foster active spatial communication and student group engagement? and (2) How do virtual field trips improve student group spatial communication learning? A design-based research approach is to be employed to obtain answers since this offers the opportunity to improve educational practice through iterative analysis, design, and implementation. Researchers and practitioners will collaborate in real-world settings to create and test design principles and solutions for educational core areas in the current curriculum of Construction Management programs in the United States. The iVisit field trip contents and technology will be informed by the conceptual frameworks for situated learning, including Problem-Based Learning (PBL), Computer-Supported Collaborative Learning (CSCL), and spatial communication in construction. Focus group interviews for instructors recruited to provide the field trip experience for their courses, will be recorded, transcribed, and analyzed via thematic analysis. By leveraging the results from the focus groups, the field trip contents and the PBL Student Activities will be created. In order to support the created contents and activities, multiple media representations of spatial data will be embedded into iVisit to digitally embody the required knowledge for learning spatial communication. These field trip contents and PBL student activities will then be used for the iVisit platform development. The NSF IUSE: EDU Program supports research and development projects to improve the effectiveness of STEM education for all students. Through the Engaged Student Learning track, the program supports the creation, exploration, and implementation of promising practices and tools. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

NSF Awards · FY 2024 · 2024-07

A major barrier to research on plant function and to crop improvement is a limitation in methods available for genetically manipulating plants. Techniques currently used include the culturing of plant tissues, the insertion or editing of DNA, and the recovery of whole plants, but each of these steps poses challenges to the degree that they work reliably in relatively few species, and even then may not work well in all varieties of the species. To fill this gap, we propose that the parasitic plant dodder (Cuscuta species) can be used to deliver gene editing molecules to a wide range of plants. Dodder plants live by attaching themselves to the stems of host plants and forming connections to withdraw water and nutrients. The organs that form the connections are called haustoria, and function somewhat similar to the way a mosquito taps into a vein to feed, and dodder is able to transmit a variety of large molecules, including proteins and RNAs, to their hosts. Another key feature of dodder is its ability to connect to an unusually wide range of host species, including the most important broadleaf crops. We will evaluate the ability of dodder to mobilize genome editing molecules into its hosts, with the goal of producing gene-edited seeds. Success in this activity would establish a novel vehicle for genetic modification of plants that is relatively simple, rapid, and broadly applicable. The project will explore multiple possibilities for transferring Cas9 and single guide RNA (sgRNA) between dodder and hosts. Among the possibilities are the movement of these molecules from an easily transformed host, such as Arabidopsis, to result in transformed dodder, or the reverse from stably transformed dodder to result in a transformed host. Given success with these, we will explore the ability for dodder to serve as a bridge between a Cas9-sgRNA expressing donor host and a target host (e.g., tomato). The project has three major aims to achieve these outcomes, including: 1) the stable transformation of dodder (C. campestris) to be used in host gene editing, 2) the development of a dodder protoplast system for rapid screening of gene editing constructs, and 3) the development of a dodder-mediated gene editing system. Preliminary results indicate that Agrobacterium-mediated transformation of dodder is possible, and the procedure will be optimized to enable generation of multiple lines bearing various transgene constructs. Other considerations include identifying promotors for the appropriate expression of gene constructs and optimized targeting for systemic trafficking of Cas9/sgRNA in the parasite-host system. For the outreach goal of this project, PIs will develop a program for refugee students to help them participate in project-related activities and develop their understanding of plant science at the University of Missouri. In summary, the project will leverage the intrinsically engaging topics of plant parasitism, RNA mobility, and genome editing to attract these students to plant science. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

NSF Awards · FY 2024 · 2024-07

With support from the Chemical Structure, Dynamics, and Mechanism A (CSDM-A) program in the Division of Chemistry, Professor Bernadette Broderick of the University of Missouri, Columbia is investigating the sublimation dynamics of molecules desorbed from an ice surface using broadband rotational spectroscopy. The molecular structures and relative abundances of the species that may result from sublimation of ices containing complex molecules remain largely unexplored. However, understanding the dynamics of sublimation is central to the water cycle, to fixing Earth’s albedo, and to cloud and aerosol dynamics in the upper atmosphere. Professor Broderick and her students will study the sublimation dynamics of various polar and nonpolar molecules desorbed from ices generated at 4 K (or warmer) within a custom-built ultrahigh vacuum apparatus. Temperature programmed desorption experiments will be conducted at various ramping rates and the structures of the desorbed products will be determined with isomer-, conformer- and vibrational-state specificity using chirped-pulse mm-wave rotational spectroscopy. Their studies could provide better understanding of chemical reactions in ices and the dynamics of sublimation which could have broad implications to the atmospheric, astrochemical, and materials science fields. The broader impacts of this work include the development of a “Freshman Interest Group” (FIG) for first-year undergraduate Chemistry majors at the University of Missouri. The CPICE apparatus, developed by the Broderick group, takes advantage of revolutionary developments in rotational spectroscopy combined with powerful buffer gas cooling methods which together open a new window into the solid to gas phase transition. First, Chirped-pulse Fourier-Transform mmWave (CP-FTmmW) spectroscopy allows for recording a rotational spectrum of several GHz in a few microseconds at sub-MHz resolution with meaningful relative intensities. Second, buffer gas cooling offers a means to overcome the disadvantageous temperature dependence of rotational spectroscopy, generally without disturbing the desorbing conformer populations or vibrational distributions. The temperature dependence of the rotational partition function is particularly problematic for ice desorption studies given that the majority of the organic molecules of interest sublime at unfavorably high temperatures. Buffer gas cooling thus gives orders of magnitude enhancement in signal levels. With CPICE, the Broderick group will explore the role of molecular complexity in sublimation dynamics. This approach allows them to monitor the molecules directly sublimed from the ices, to detect a broad range of polyatomic systems with increasing molecular complexity, to achieve conformerspecific detection at desorption, and to employ CP-FTmmW spectroscopy with instantaneous scans and reliable branching determination. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

NSF Awards · FY 2024 · 2024-07

This project aims to identify trends in the demographics and turnover behavior of the STEM teacher workforce. It focuses on specific remedies and investments needed to retain prospective teachers in high-need schools, especially rural communities, and to improve outcomes for their students. The project includes two complementary studies, one using the National Teacher and Principal Survey (an update from the earlier Schools and Staffing Survey) and a second, using longitudinal administrative data from the states of Kansas and Missouri. The project will explore a range of questions, including: how STEM teacher demographics, turnover intentions, and actual turnover may have changed nationally due to the COVID-19 pandemic; and how the Great Recession of 2007-08 and the COVID-19 pandemic may have influenced teacher outcomes. This body of research will produce insights to inform actionable recruitment and retention practices for high-need school districts and future research focused on teacher labor markets. The conceptual framework and proposed analyses build upon a model of teacher turnover that suggests three main categories of factors that drive teacher turnover: teacher factors, school factors, and external factors and events. Leveraging this framework, the investigators group the research questions and analyses into three broad themes: STEM teacher characteristics, the school and student characteristics in which STEM teachers are employed, and contemporary secular trends that impact STEM teachers. They also consider the interplay between the STEM teacher characteristics and the school context in which STEM teachers work. The investigating team will employ descriptive and regression analyses to answer the research questions. Across interconnected lines of inquiry, the researchers will balance national generalizability with comprehensive state-specific application to inform current and future practice, policy, and research. This project is supported by the EHR Core Research(ECR) program. The ECR program emphasizes fundamental STEM education research that generates foundational knowledge in the field. Investments are made in critical areas that are essential, broad and enduring: STEM learning and STEM learning environments, broadening participation in STEM, and STEM workforce development. The program supports the accumulation of robust evidence to inform efforts to understand, build theory to explain, and suggest intervention and innovations to address persistent issues in STEM education. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

NIH Research Projects · FY 2026 · 2024-07

Project Summary/Abstract My research program is focused on the intersection of pro-folding chaperones and the pro-degradation 26S proteasome. Protein Quality Control (PQC) is the balance of protein folding, unfolding and degradation, which is central to human health and disease. An outstanding question in the PQC field is “how do chaperone proteins triage substrate proteins between the pro-folding and pro-degradation pathways?” In my graduate and postdoctoral training, I have gained experience using in vitro techniques to study both chaperone proteins and the 26S proteasome. This positions me to explore how chaperone activity and substrate processing affect downstream degradation by the proteasome. This work will bridge the gap between two major cellular pathways that, to-date, have been characterized independently. Our goal over the next five years will be to use a multi-disciplinary approach to study how the chaperone complex, Hsp70/CHIP/BAG-1, affects proteasomal degradation. Hsp70 is a molecular chaperone and ATPase that binds and releases substrates throughout an ATP-hydrolysis cycle that is regulated by co- chaperone proteins. Two such co-chaperones are C-terminus of Hsc70-interacting protein (CHIP), an E3 ubiquitin ligase, and Bcl-2 associated athanogene-1 (BAG-1), a nucleotide exchange factor. The Hsp70/CHIP/BAG-1 complex has been shown to target human disease substrates, such as mutant huntingtin and immature BCR-ABL oncoproteins, to the proteasome for degradation. Therefore, this is an ideal chaperone complex for developing my research program. I propose to use in vitro characterization to dissect how chaperones influence each step of proteasomal degradation, including ubiquitination, substrate binding, and degradation. In addition, we will employ cryo- electron microscopy to determine first-of-its kind structures that directly observe the substrate handoff mechanism from chaperones to the 26S proteasome. These techniques will be paired with single molecule Fluorescence Resonance Energy Transfer (smFRET) experiments that report on the conformational state of Hsp70 during substrate processing. Tracking the changes in Hsp70 will demonstrate how interactions with co-chaperones and the proteasome affect the conformational landscape during substrate processing. Combining these in vitro techniques to rigorously study how chaperones mediate proteasomal degradation will provide unique insights into the molecular mechanisms that affect substrate handoff and degradation. Furthermore, I expect that our data will lead to novel strategies for targeting this process in human disease.

NSF Awards · FY 2024 · 2024-07

Huge volumes of omics data such as genomics, transcriptomics, and proteomics data have been generated by high-throughput sequencing experiments. Extracting biological knowledge regarding gene regulation mechanisms of cells from multiple sources of heterogeneous omics data is a significant computational challenge, which is critical for leveraging the data to address various biological problems such as how genes are regulated under different biological conditions and how genotypes (e.g., genetic mutations) cause phenotypes (e.g., physical features). The overarching goal of this project is to develop cutting-edge artificial intelligence (AI) methods based on transformers to infer gene regulatory relationships (i.e., gene regulatory networks) from omics data more accurately than before. The pretrained transformer tools can be broadly used to study gene regulation in various biological systems such as bacteria, plants, and animals. The publicly released course materials, web sites, videos, databases, software tools, tutorials, user manuals, and the online learning community on social networks will boost gene regulatory network modeling in bioinformatics and AI. The course modules and training activities will enrich both AI and bioinformatics education at middle/high school, undergraduate, and graduate levels. The combination of AI and omics data analysis will promote the diversity in AI, computing, and bioinformatics by attracting and training underrepresented minority and women students. The project will engage the local public and the Missouri State Legislature to advocate for the importance of scientific research for the society and economy. This project aims to achieve three specific objectives: (1) developing transformers to predict transcription factor binding sites on chromosomes/genomes from omics data, including genomics, transcriptomics, epigenomics, and protein sequence and structure data; (2) developing self-supervised graph transformers to infer gene regulatory networks by integrating omics data and transcription factor binding site predictions; and (3) develop graph transformers to infer gene regulatory networks from single-cell omics data via transfer learning. The first self-supervised learning-based transformers to tackle this problem will improve the accuracy of inferring gene regulatory networks over existing unsupervised methods. The self-supervised learning will overcome the weakness of existing supervised methods not effectively dealing with the problem of lacking labelled data. The transformers can predict entire gene regulatory networks as graphs, leveraging the inter-dependence between multiple transcription factor-gene regulations that the current supervised methods of predicting the regulatory relationship for one pair of transcription factor and gene a time cannot. Moreover, the graph transformers use uniform graph representations to integrate multiple modalities of omics data under the same graph framework, which are more scalable and effective than the existing methods that use different ways to process different data. Furthermore, the transformers can predict gene regulatory networks from the data of both single cells and a population of cells (bulk cells) and use transfer learning to fine-tune the models pretrained on bulk-cell data to improve the highly challenging single-cell gene regulatory network inference for the first time, which is likely much more effective than the existing methods of separating the gene regulation inference from bulk-cell and single-cell omics data as two independent problems. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

NSF Awards · FY 2024 · 2024-06

This CAREER research project will develop new econometric and statistical tools for identifying and estimating causal effects in settings where the current approaches impose unrealistic assumptions. The validity of every econometric method is grounded in the assumptions placed on the model. In some cases, these assumptions may be fundamental to the identification and estimation strategy, but ultimately unrealistic in real economic settings. Research that uses these strategies to estimate policy effects or causal impacts may be unreliable if these assumptions are not true. This project will provide alternative strategies that are valid without unrealistic assumptions. The project also will develop methods to test for the legitimacy of underlying assumptions. To ensure the usability of the proposed methods, code will be developed for popular statistical software and will be posted in publicly accessible software repositories. By examining what fundamental assumptions are used to identify causal effects, what the implication of these assumptions are, and how to determine if the assumptions are realistic, this project will contribute to the continual improvement of accurate empirical analysis, an essential input for successful economic policy making. In terms of educational activities, the investigator will support the pipeline of students into economics through the development and mentorship of undergraduate student groups and undergraduate research experiences. To facilitate that activity, the investigator will develop and analyze surveys to determine which student activities are most impactful and make available supporting material on public online platforms for other educators to use. In the estimation of causal effects and policy evaluation, models of endogeneity are commonplace as individuals or states who choose treatment or to enact a policy often are different than those who do not in unobservable ways. The control function approach is a popular method that addresses endogeneity by controlling for the unobserved differences. However, current control function approaches are limited by unnecessary and often unrealistic restrictions in the identification strategy. This research consists of three projects aimed at eliminating these restrictions and developing a more general control function approach. First is the identification of triangular random coefficient models with continuous endogenous variables. Unlike current control function approaches in the literature, this project will develop a general control function approach that does not depend on scalar heterogeneity in the first stage. The second project will extend the first to the setting of binary endogenous variables; i.e., the policy evaluation setting. The current literature depends critically on a monotonicity assumption in the first stage to identify local average treatment effects, whereas the proposed general control function approach will not. The final project will explore the sensitivity of control function approaches to misspecification of nonlinearity and heteroskedasticity as well as provide guidance to empirical researchers on how to compose specifications that are flexible enough to avoid these issues. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

NIH Research Projects · FY 2026 · 2024-06

PROJECT SUMMARY/ABSTRACT Cardiovascular disease (CVD) is the main cause of death in older adults in the US and the burden of aging- associated CVD is expected to grow as the percentage of the older population steadily grows. A key characteristic of vascular aging is arterial stiffening, which is a causal factor and independent prognosticator of cardiovascular morbidity and mortality. Even though increased arterial stiffness contributes to the pathogenesis of CVD, the mechanisms underlying arterial stiffening in aging remain poorly understood. Further, there are currently no treatments available that directly target arterial stiffening. This project addresses these significant gaps in knowledge. The long-term goal is to elucidate the molecular mechanisms causing aging-related arterial stiffening that can be therapeutically targeted to prevent the development and/or reverse the progression of CVD. Arterial stiffening has been attributed to remodeling of the extracellular matrix of the vascular wall, particularly to increased deposition of adventitial collagen. However, the role of vascular smooth muscle cell (VSMC) stiffening in the pathogenesis of aging-associated arterial stiffening is increasingly recognized. Based on rigorous published research and preliminary studies, the central hypothesis of this project is that VSMC activation of Ras homolog family member A (RhoA)/Rho-associated protein kinase (ROCK) in aging causes LIM kinase (LIMK)-dependent actin polymerization, stress fiber formation, and consequent arterial stiffening, an effect that can be reversed by inhibiting sodium glucose co-transporter 2 (SGLT2). A corollary to this hypothesis is that treating older adults with an SGLT2 inhibitor will reduce arterial stiffness. The hypothesis will be tested using gain- and loss-of-function genetic manipulation and pharmacological experiments in isolated arteries from younger and older individuals and in cultured VSMC. Mechanistic studies will be complemented by the first clinical trial to purposely test the efficacy of SGLT2 inhibition in reversing aging-related arterial stiffening. Specifically, studies in Aim 1 will determine the role of VSMC RhoA/ROCK activation and LIMK-dependent actin polymerization in arterial stiffening in aging, and the effects of SGLT2 inhibition on this pathway. In Aim 2, the effects of empagliflozin, an SGLT2 inhibitor, on arterial stiffness in older individuals will be determined. It is posited that SGLT2 inhibition holds extraordinary promise for reversing arterial stiffening in older adults, and ultimately ameliorating CVD.

NIH Research Projects · FY 2026 · 2024-04

Project Summary/Abstract Epidemiological data have established an increased incidence of cardiovascular disease events in obese individuals, with these events being strongly associated with excessive arterial stiffness. Elevated aldosterone levels and activation of vascular mineralocorticoid receptors (MRs) contribute to obesity related arterial stiffening. Studies by our group and others have further shown that enhanced endothelial cell (EC) mineralocorticoid receptor (ECMR) and its downstream epithelial sodium channel (EnNaC) signaling, induce arterial and EC stiffening together with oxidative stress and inflammation. Conversely, ECMR/EnNaC deletion prevents diet or aldosterone induced excessive endothelial and arterial stiffness. Our recent data further indicate that activation of the ECMR increases expression of EC deubiquitinating enzymes and that endothelial ubiquitin-specific protease 8 (ECUSP8) plays a dominant role in preventing EnNaC ubiquitination and degradation, leading to increases in EC endosomal EnNaC. Moreover, enhanced ECMR/ECUSP8 signaling also promotes endosomal EnNaC trafficking and release of exosomal EnNaC. Importantly, exosomal EnNaC, released from endosomes, is re-uptaken and in turn impacts on EC/vascular smooth muscle cell (VSMC) and arterial stiffening. Our research hypothesis is that ECMR activation enhances ECUSP8 signaling that increases endosomal EnNaC, endosome trafficking, plasma membrane EnNaC, and release of exosomal EnNaC, resulting in EC/VSMC and arterial stiffening. This notion is supported by the fact that obesity is a major public health issue in the United States, and it is associated with cardiovascular MR activation and vascular disease. To address this hypothesis in vivo and in vitro, models of ECMR/ECUSP8/EnNaC activation will include a high fat, high sucrose diet (diet induced obesity) and aldosterone administration, respectively. A cross-sectional human study will be included to investigate the correlation between plasma exosomal EnNaC and arterial stiffening in clinically obese and hypertensive patients. Aim 1 of this application proposes to determine whether ECMR activation enhances ECUSP8 signaling that increases endosomal EnNaC, endosome trafficking, plasma membrane EnNaC content, and EC and arterial stiffening. Aim 2 will determine determine whether ECUSP8 signaling increases release of EC derived exosomal EnNaC that is uptaken by ECs/VSMCs and in turn impacts on arterial stiffening. The proposed innovative research program will provide enhanced understanding of the interactions between ECMR/ECUSP8/EnNaC activation, endosome trafficking, release of exosmes, and identify novel therapeutic targets and strategies for the early diagnosis and prevention of obesity induced vascular stiffening and related cardiovascular complications.

NIH Research Projects · FY 2026 · 2024-04

Summary/Abstract Abdominal aortic aneurysm (AAA) is a potentially lethal disease that lacks pharmacological treatment. Although vascular inflammation is the initial event leading to AAA formation, aorta rupture due to artery wall weakening is responsible for the high mortality rate in this silent killer. Aortic wall weakening in AAA is primarily caused by aorta media degeneration, elastin breakage and impaired adventitia response. The media degeneration is driven by programmed cell death (e.g., apoptosis and necroptosis) of medial smooth muscle cells (SMC). However, there are critical knowledge gaps concerning mechanism(s) or key factor(s) governing SMC survival in aortic wall. Moreover, adventitia thickening due to fibroblastic response is crucial for strengthening aorta wall and impeding AAA progression. Compromised adventitial responses along with medial degeneration make the aorta highly vulnerable to rupture. However, it remains largely unknown how the adventitia fibroblastic response is regulated. Exciting preliminary data indicate that Smad2 is downregulated in both mouse and human AAA lesions. Smad2 deficiency with SM22α-Cre mice (S2sm22-/-) exacerbates AAA formation/dissection in both angiotensin II (Ang II) infusion and elastase models. S2sm22-/- aggravates elastin fragmentation, causes larger aorta dilation and greater SMC loss with less adventitia thickening than wildtype (WT) ApoE-/- mice in AAA. Importantly, Smad2 deficiency exacerbates SMC necroptosis both in vivo in aorta media and in vitro in culture SMCs. Moreover, lineage tracing studies indicate that Smad2 deficiency in SMCs attenuates SMC trans-differentiation to adventitial Sca1 (advSca1) cells and diminishes adventitial fibroblast proliferation and collagen deposition. These compelling data strongly support a novel hypothesis that SMC- driven Smad2 mitigates AAA progression by alleviating SMC necroptosis in aorta media while promoting protective fibroblast response in adventitia. Using primary mouse and human SMCs, in vivo Smad2 SMC- specific knockout mouse and two AAA models combining with molecular, cellular, histological, and cutting- edge CUT&RUN sequencing and single cell RNA sequencing analyses, the hypothesis will be tested by two specific aims: Aim 1 is to determine the impact of Smad2 deficiency on AAA formation/dissection; and Aim 2 is to establish molecular mechanisms by which Smad2 preserves aortic wall integrity essential for hindering AAA formation/dissection. Successful completion of the proposed studies will establish novel mechanisms regulating SMC necroptosis and adventitial protective responses, which are likely to advance our understanding of the AAA progression and dissection and ultimately lead to novel strategies for developing effective therapeutics to treat AAA/dissection.

NIH Research Projects · FY 2026 · 2024-04

Project Summary Caregivers of children with autism spectrum disorders often recall differences in their children as early as infancy, despite most children with autism being diagnosed after age 3. Caregiver recall of behavioral differences in infancy indicates that there is more to learn from the earliest developmental periods of children later diagnosed with autism that could ultimately contribute to earlier screening and earlier interventions. Understanding the prodromal period could identify sources of heterogeneity in autism phenotypes, such as social communication deficits and delayed language, which are highly variable and predictive of long-term outcomes in the autism population. Investigating emerging communication processes is an important domain to focus on in early development. Infant cries are part of the earliest communicative exchanges for humans. Cry characteristics impact caregiver perceptions and responses to their infants and thus may impact early communication development. Differences in cry acoustics associated with later autism diagnoses have been observed as early as 6 months, and caregivers have perceived autism-related differences in cries from infants as young as 1-month of age. These findings support cry acoustics as an early risk marker of autism. Aim 1 will replicate and extend the association between caregiver cry perception and autism outcomes to aid in identification of the objective acoustic features driving the perceptual differences , requiring collection of new caregiver ratings of cries from an existing library. Aim 2 will consist of detailed analysis of existing daylong recordings to capture a phenotype of social contingency development through analysis of caregiver- infant turn-taking involving cry over the first 12 months of life. The project will utilize recordings collected at 1, 3, 6, 9, and 12 months in children with and without autism. In addressing these aims and preparing for a career as an independent investigator, the PI will be trained in three primary areas: 1) the autism spectrum disorder phenotype and clinical knowledge, 2) measurement and data analysis relevant to prospective longitudinal studies of developmental disorders and developmental trajectory phenotypes, and 3) professional development, especially focused on training in grant writing and presenting research to multiple academic disciplines and stakeholders. The research projects and training plan leverage the sponsor and co-sponsor’s existing data (cry recordings and daylong recordings collected longitudinally), expertise in autism and infant cry (sponsor) and statistical analysis (co-sponsor), experience in training and mentoring (sponsor and co-sponsor), and the PIs strong foundation of research experience and commitment to multi- disciplinary research of atypical language acquisition.

NIH Research Projects · FY 2025 · 2024-02

Abstract Ultra-high dose rate (UHDR) radiation delivery, termed FLASH radiotherapy (FLASH-RT), has the potential to reduce normal tissue damage, with significant clinical cancer treatment ramifications. Current evidence suggests that FLASH-RT reduces functional damage to normal brain, colon, lung, and skin, at the same dose values. Although controversial, some studies show this reduction in tissue damage as great as 40%, despite tissue type alpha/beta ratio and total dose remain significant unknown factors. Most surprisingly tumor tissue appears unaffected by FLASH radiation sparing, suggesting that the therapeutic ratio achieved through FLASH-RT is higher than conventional RT. The potential to achieve higher therapeutic ratios make FLASH-RT very attractive for future human use to address radioresistant tumors that would otherwise result in excessive radiotoxicity during conventional treatment. Despite clinical translation of FLASH-RT to large animal and human studies being urgently warranted, the majority of the preclinical work for FLASH-RT remains in small animals, where concerns regarding dose and dose rate inhomogeneities cannot be adequately assessed. A major barrier towards translational FLASH-RT is that optimization of treatment plans for large animals and humans with larger/deeper tissues and complicated geometries remains challenging. In order to demonstrate the hypothesized superiority of FLASH-RT, it is essential to conduct the studies FLASH-RT studies under controlled conditions and in clinically realistic workflows. This begins with a treatment planning system {TPS) capable of generating and delivering comparable plans for FLASH/CONV-RT within a minimally modified clinical setting. In the current proposal, we are committed to developing such a TPS for the first time and making our software available to the scientific community. We will achieve this by first generating beam models for FLASH-capable linacs. These beam models will then be used to implement advanced planning and delivery technology utilizing passive intensity modulation. Next, we will develop tumor control probability and normal tissue complication probability models deployable on the TPS. Lastly, our work will culminate in demonstrating successful deliveries of optimized plans with comprehensive characterization of plan delivery using quality assurance systems uniquely available at Dartmouth. Due to the urgency to transfer this paradigm-shifting therapy, high-risk of the first initiative, the exploratory, and developmental nature of the proposal, the R21 grant mechanism is leveraged and justified. The successful completion of the proposed work will advance the state-of-the-art in FLASH-RT by bridging the extensive gap between the basic science of FLASH and the clinical needs of FLASH for translation to human trials. The team has leading expertise in radiation physics, informatics, and radiation oncology, and are supported by existing FLASH-capable linacs, TPS prototypes, unique UHDR dosimetry technologies invented at Dartmouth, canine pilot trials, future human trials in planning and leading industrial partners. Taken together, the team is ideally poised to conduct the proposed work of exploratory and developmental nature.

NIH Research Projects · FY 2025 · 2024-01

Project Summary Stem-cell based strategy has been widely considered as a promising approach to replace damaged pulp and dentin structures and restore their biological functions in regenerative endodontics. However, regeneration of functional tubular dentin has been a challenge owing to the lack of understanding dental pulp stem cell (DPSC) polarization and differentiation as well as the underlying mechanism that are prerequisite for tubular dentin regeneration. A unique biomimetic 3D platform was recently developed to study DPSC polarization and differentiation in the PI’s group. This platform can precisely manipulate single cells on each microisland of the 3D platform and is an excellent tool to decipher the biophysical and biochemical signals that initiate and regulate DPSC polarization at the single cell level. A variety of biophysical factors were screened using this 3D platform, and the nanofibrous architecture and tubular structure of the matrix were identified to be the two critical biophysical factors that initiate and regulate DPSC polarization. The combination of RNA-seq with laser microdissection techniques and a conditional knockout model further identified that TGF-1 is a crucial biochemical factor for odontogenesis. Consequently, the hypothesis of this work is that DPSC polarization is controlled by a dynamic signaling network composed of a set of critical biophysical and biochemical factors, and integration of these factors in scaffolding design will regenerate tubular dentin from DPSCs. Therefore, the overall objective of this proposal is to explore and optimize the parameters that initiate/modulate DPSC polarization, understand the underlying mechanism of DPSC polarization, and regenerate tubular dentin in vivo. To accomplish the overall objective for this project, three specific aims are proposed. Aim 1 will explore how the biomimetic tubular matrix modulates DPSC polarization and differentiation. Aim 2 will examine how TGF-1 regulates DPSC polarization and differentiation. Aim 3 will integrate TGF-1 into the biomimetic tubular matrix to regenerate tubular dentin in vivo. Successfully completing this work will fundamentally advance the understanding of DPSC polarization and differentiation, and greatly promote the ability to develop new bio- inspired matrices to regenerate functional tubular dentin for regenerative dental therapies.

NIH Research Projects · FY 2025 · 2024-01

Project Summary Periodontitis is a highly prevalent oral disease among US adults and is the primary cause of the loss of permanent teeth. It was recently estimated that 42% of US adults aged 30 years or older have periodontitis, with 7.8% having severe periodontitis. Destructive periodontitis is characterized by the loss of dental supporting tissues including alveolar bone. Clinically, alveolar bone loss can be broadly divided into vertical (intrabony) and horizontal (suprabony) bone loss. Surprisingly, horizontal bone loss in periodontitis is the most common problem confronting clinicians but has received scant attention. Currently, there are no products offering satisfactory outcomes for the treatment of horizontal alveolar bone loss. Therefore, it is clinical significance to develop innovative biomaterials and technology for horizontal alveolar bone regeneration. In the preliminary studies, a multifunctional injectable nanofibrous ECM-mimicking microsphere (MINE-MS) system with several unique features was designed and fabricated. These features include high mechanical strength, excellent injectability and cytocompatibility, fast setting time, strong antibacterial activity, and high osteoinductivity. In addition, a short peptide E7 that has high specific affinity to bone marrow derived mesenchymal stem cells (BMSCs) and repels epithelial and gingival fibroblast cells was identified. When the E7 peptide was conjugated to the MINE-MS surface, the MINE-MS served as an excellent biological barrier to selectively repopulate cells by significantly increasing BMSCs and expelling epithelia and fibroblasts both in vitro and in vivo. Furthermore, the pilot experiment shows that the MINE-MS successfully elevated the alveolar crest and regenerated more bone than enamel matrix derivative (a clinical product for periodontitis treatment) in a mouse periodontitis-induced horizontal bone loss model. These exciting findings make the MINE-MS an excellent candidate for the treatment of horizontal alveolar bone loss in periodontitis. The proposed project, therefore, is to develop and optimize the MINE-MS system for horizontal alveolar bone regeneration. Three specific aims are proposed in this work. Aim 1 is to synthesize the MINE-MS and optimize the properties, including the injectability, setting time, mechanical strength, cytocompatibility, and antibacterial activity. Aim 2 focuses on incorporating the BMSC affinity peptide onto the MINE-MS surface, evaluating and optimizing its function as a biological barrier for selective cell repopulation using a competitive cell adhesion assay in vitro and a periodontal fenestration defect rat model. In Aim 3, an osteogenic peptide-loaded nanospheres will be incorporated into the core of the MINE-MS and its function for enhanced bone regeneration will be examined. Lastly, the optimized MINE-MS will be tested for periodontal alveolar bone regeneration in a rat periodontitis-induced horizontal bone loss model. Successful completion of this project will address the challenge of periodontitis-induced horizontal alveolar bone loss, making a significant step towards periodontal alveolar bone regeneration in clinic.

NIH Research Projects · FY 2026 · 2024-01

ABSTRACT Ischemic stroke leads to a loss of blood flow to the brain and is a prominent cause of death and disability in affected individuals. Whereas neuroprotective agents have shown limited clinical benefits for treatment of stroke, vascular interventions are promising targets for therapy. Nevertheless, restoration of bloodflow following these treatments is often incomplete. Surprisingly, the role of vascular survival and function within the injured tissue following ischemia/reperfusion (I/R) is largely unexplored. Mitochondrial membrane potential (ΔΨm) depolarization and increases in mitochondrial Ca2+ are key signaling events in cell death, but the effects of targeting vascular mitochondrial Ca2+ signaling and ΔΨm depolarization on neuronal outcomes is unknown. Upon reperfusion following ischemia, the production of reactive oxygen species (ROS) damages surrounding neuronal and vascular tissues. In resistance arteries of mice, posterior cerebral artery smooth muscle cells (SMCs) are more susceptible than endothelial cells (ECs) to cell death induced by oxidative stress imposed by H2O2. Furthermore, vascular cells from females are more resilient to mitochondrial (intrinsic) apoptosis to H2O2 compared to males. However, the mechanisms mediating this protection in females is unknown. To address this gap in knowledge, the Specific Aims of this project will test the central hypothesis that sex-based differences in mitochondrial Ca2+ signaling and ΔΨm regulation underly greater vascular cell resilience to acute oxidative stress in PCAs of female vs. male mice. To investigate these relationships, sex differences in mitochondrial Ca2+ signaling and ΔΨm depolarization during exposure to H2O2 (200 μM for 50 min) will be evaluated in isolated, pressurized cerebral arteries and native endothelial tubes (Aim 1). Complimentary experiments will test the effects of Ca2+ channel signaling induced by acute oxidative stress on mitochondrial Ca2+ and ΔΨm depolarization. The proposal will additionally examine how differences in electron transport function and reverse activation of ATP synthase between males and females contribute to greater cell death in males (Aim 2). Using a middle cerebral artery occlusion model, experiments will evaluate the role of mitochondrial Ca2+ signaling and ΔΨm depolarization to arterial damage in males and females following I/R in vivo (Aim 3). These findings will be correlated to neuronal survival and behavioral deficits, to gain further understanding to how vascular survival can improve neuronal outcomes. Gaining new understanding of how to target intrinsic mechanisms of protection inherent to females to promote vascular resilience in the cerebral circulation following I/R injury to the brain will yield new insight into preserving vascular function and associated neuronal outcomes. Such findings provide foundational knowledge regarding sex differences in vascular mitochondrial function and will facilitate the development of novel avenues for therapy targeting the vasculature for patients after stroke and other conditions of oxidative stress in the brain such as traumatic brain injury.

NIH Research Projects · FY 2026 · 2024-01

ABSTRACT Sjögren's disease is an autoimmune condition characterized by chronic inflammation and diminished secretory function of the salivary glands. Although extensive investigation has been done to understand it, causes of and effective treatments for the disease are still unknown. Given the high degree of need and the limitations of current therapies, development of novel treatments to decrease inflammation and restore salivary gland secretory function is essential. Previous studies demonstrated that a treatment with aspirin-triggered RvD1 and dexamethasone (AT-RvD1/DEX) reverses Sjögren's disease-like features in NOD/ShiLtJ mice at disease onset but the utility of this treatment is currently limited because the minimum effective dosage has yet to be established. Specifically, although AT-RvD1 has no known side effects, its relatively high cost could limit affordability. More importantly, DEX has been demonstrated to have significant side effects that can be expected to impede long-term use. By determining AT-RvD1/DEX biodistribution using mathematical modeling and thus defining the optimal (i.e., minimum effective) treatment dose, it is possible to manage the issues presented by both drugs and in so doing produce a cost-effective and clinically safe treatment option to mitigate symptoms associated with Sjögren's disease. To that end, it is hypothesized that systemic delivery of AT-RvD1/DEX will restore salivary gland secretory function in Sjögren's disease. Aim 1 will reduce AT-RvD1/DEX doses to their minimum effective levels, while Aim 2 will explore mechanisms by which AT-RvD1/DEX treatment outcomes are achieved and Aim 3 will apply AT-RvD1/DEX treatment to humanized systems.

NIH Research Projects · FY 2026 · 2024-01

Project Summary/Abstract Relatively little is known about SMARD1 and CMT2S and the disease-causing gene IGHMBP2 as it relates to disease development. Therapeutic options are, at best, minimal as no approved drugs exist. The objective of this project is to understand the consequences of disease-causing mutations in IGHMBP2 that result in SMA with Respiratory Distress (SMARD1) or Charcot Marie Tooth Type 2S (CMT2S). Towards this goal, we have generated six Ighmbp2 mouse models that are based on patient mutations in IGHMBP2. These models represent the first, patient-based models of SMARD1 and CMT2S. Importantly, we demonstrate that each mutation thus far studied demonstrates distinct disease phenotypes. These investigations are designed to further our understanding of IGHMBP2 and its functional significance in disease development by utilizing the Ighmbp2 mouse models and complementary approaches: genetics and biochemistry. Aim I of this proposal examines the phenotypic and molecular changes that result from Ighmbp2 mutations R604X and H922Y and the effect of these mutations on disease progression and therapeutic efficacy. Examining the similarities and differences between these mutations should provide valuable information towards what molecular alterations result in the more severe SMARD1 or less severe CMT2S. Therapeutic studies proposed will help us understand what aspects of disease pathology are altered and to what extent. Aim II utilizes biochemistry to investigate how these IGHMBP2 mutations effect IGHMBP2 function and the association of proteins in IGHMBP2 pathways. RNA and protein stability, protein binding affinity, ATPase and helicase activity and processivity for these mutants will be examined in the presence of absence of ABT1, a protein that binds IGHMBP2 and increases IGHMBP2 ATPase and helicase activity and processivity. It will be important to determine how each of these mutations alter IGHMBP2 biochemical function and how altered IGHMBP2 biochemical function relates to disease. Our previous studies suggest that IGHMBP2-ABT1 function in 47S pre- rRNA processing; Aim III expands on these studies. Our laboratory has developed reagents aimed at addressing IGHMBP2-ABT1 function in neuronal and non-neuronal contexts. 47S pre-rRNA processing will be examined in wild type and mutant contexts to determine whether and to what extent processing is altered. We will also ask whether any processing defects can be eliminated following therapeutic delivery of IGHMBP2 or ABT1. Each Aim of this proposal should provide independent relevant information towards understanding disease development and progression, IGHMBP2 biological processes and targets for therapeutic development. Determining the functional differences between IGHMBP2 mutations that result in SMARD1 versus CMT2S has important therapeutic implications since a subtle increase in functionality can have profound clinical implications. This proposal is a natural collaboration of MU investigators within molecular biology and neurodegenerative fields. Each investigator provides their own unique expertise towards the successful completion of these Aims.

NIH Research Projects · FY 2026 · 2023-12

My research goal is to understand the pathophysiology of HFpEF (Heart Failure with preserved Ejection Fraction) and identify its therapeutic targets. Compelling evidence suggests that the pathophysiology of HFpEF in men and women is distinct, leading to differential phenotypes, responses to treatment, and a potential need for sex- specific therapeutic intervention. Studying sex differences in HFpEF is an essential step toward establishing a personalized therapeutic strategy. Women in HFpEF are typically in their postmenopausal state. Although women comprise the majority of HFpEF patients, the preclinical study of female HFpEF pathogenesis is limited due to a lack of animal models. Female mice, both cycling (premenopausal) and non-cycling (induced by ovariectomy), resist HFpEF development. One of the novelties of my proposed work is to use a new female HFpEF-like model induced by ovary-intact menopause (by VCD (Vinyl Cyclohexene Dioxide) injection) combined with metabolic stress. The VCD- postmenopausal differs from the ovariectomized (OVX) model since it retains residual ovarian stroma, analogous to natural menopause in women. VCD mice subjected to metabolic stress develop robust HFpEF phenotype. In addition to estrogen deficiency, women with natural menopause also experience relative androgen excess (RAE) due to the remaining androgen-producing capacity of the residual ovaries. Clinical studies show that a high androgen/estrogen ratio (not a low level of estrogen alone) is associated with increased cardiovascular risks in women. Androgens suppress NP (Natriuretic Peptide) production from atrial cells, a critical activator of cGMP- PKG signaling. Importantly, a deficiency of myocardial cGMP-PKG activity was reported to underlie myofilament dysfunction in HFpEF. My proposed work focuses on myofilament-based alterations that are responsible for mechanical dysfunction in HFpEF. Aim 1 will focus on sex-specific myofilament alterations. The diastolic function will be evaluated at the in vivo LV, the myocardium, and single cardiomyocyte levels. Diastolic stiffness, relaxation kinetics, crossbridge kinetics, myofilament Ca2+ sensitivity, and Ca2+ release-reuptake kinetics will be investigated. Passive sarcomere stiffness and the stiffness contribution of ECM (extracellular matrix) will be measured. Myofilament (phospho)proteomics, transcriptomics, activity assay, protein and RNA studies, etc., will investigate the signaling pathways associated with these mechanical changes. Aim 2 will elucidate the role of RAE and anti-androgens’ effect on diastolic function in postmenopausal HFpEF. The impact of RAE will be studied in 2 postmenopausal models: 1) the OVX model (low estrogens and low androgens); and 2) the VCD model (low estrogens and normal androgens). The contribution of RAE will be revealed through the inhibition of 5α-reductase (by anti-androgens). I anticipate that this proposed work will advance our knowledge of the sarcomere-based alterations in HFpEF and provide potential insight to alleviate diastolic dysfunction in a sex-specific manner.

NIH Research Projects · FY 2025 · 2023-12

Project Summary HIV remains a significant problem worldwide. The CA protein of HIV is involved in several critical replication events, including Gag oligomerization and viral assembly, maturation, reverse transcription (RT), trafficking to the nucleus via interaction with host factors, nuclear import, integration, and evasion of host immune responses. Despite significant advances in our understanding of the role of CA in replication, there are many unresolved questions regarding CA structural dynamics during viral assembly and post-entry replication steps, CA-host factor interactions, and the impact of these interactions on virus biology. The genetic fragility of CA and difficulty of examining CA-host interactions in cells represent significant barriers to the resolution of these questions. To address these challenges and knowledge gaps, we are working to identify and develop novel tools capable of discriminating among different CA assembly forms. To date, we have identified RNA aptamers that bind specifically to the CA lattice, but not other assembly forms, and those that bind both the CA lattice and CA hexamer assembly forms. Aptamers represent unique tools particularly well-suited to the study of CA assembly forms and interaction sites, as they bind targets with high specificity, discriminate among different conformations of the same protein, can be expressed in or delivered to cells, can be used to outcompete other interacting partners, and are amenable to a variety of different modifications. Interestingly, our aptamers identified to date display different biological phenotypes, suggesting that they may target unique sites on CA or influence CA function in distinct ways. Here, we propose two aims in support of our goal to develop aptamers as useful tools for the field. The focus of Aim 1 is to identify new aptamers that target additional CA assembly forms, building upon our prior work supporting feasibility of our approach. Our ultimate goal is to develop a panel of aptamers with specificities to all relevant CA assembly states. The focus of Aim 2 is to develop an aptamer-mediated, CA assembly state-specific affinity purification method paired with crosslinking mass spectrometry to identify novel CA assembly state-associated host factors. Collectively, these tools will tremendously benefit the field, as there are currently no tools available for the differentiation of CA assembly states. Importantly, aptamers are amenable to a variety of modifications that will facilitate applications including affinity purification, microscopy-based tracking of CA during replication, expression in cells for evaluation of replication effects and mechanistic studies, and delivery to cells to compete for binding to specific CA sites. Furthermore, future determination of sites of aptamer-CA interaction will help identify novel accessible sites on CA for potential therapeutic targeting.

NIH Research Projects · FY 2024 · 2023-10

Urinary tract obstruction causes kidney injury, which, if left uncorrected, may lead to an irreversible renal loss especially in infants. The pathophysiology of neonatal obstructive nephropathy has been a focus of considerable research interests for decades, but significant gaps in understanding include vascular mechanisms that underlie impairment of renal microcirculation. In the present application, we propose a novel concept that alterations of newborn renal vascular resistance (RVR) and perfusion by acute ureteral obstruction are mediated by reactive oxygen species-driven biosynthesis of peptidase endothelin-converting enzyme 1, which proteolytically processes multiple renal big endothelins (ET1-3) to their vasoactive isoforms. ET-derived renal diacylglycerol (DAG) activates renal vascular smooth muscle cell TRPC3 channels, leading to receptor-operated extracellular calcium entry, prolonged vasoconstriction, RVR elevation, and hypoperfusion. To investigate these concepts, we will utilize newborn pigs that are maintained under intensive care as a preclinical model for reversible urinary tract obstruction in infants. These pigs and a novel TRPC3 knockout neonatal rat strain will be used to delineate calcium-dependent signal transduction mechanisms in renal vascular smooth muscle cells that mediate 1) persistent hypoperfusion, 2) kidney injury, and 3) impaired myogenic renal autoregulation during and after acute urinary tract obstruction. The proposed studies in this application will accrue mechanistic data that will not only improve our understanding of neonatal renal vasculopathy but may lead to potential diagnostic markers or therapeutic targets for obstructive renal insufficiency in newborns.

NIH Research Projects · FY 2024 · 2023-09

PROJECT SUMMARY Tuft cells are rare cholinergic chemosensory epithelial cells capable of producing an unusual spectrum of biological effector molecules, such as interleukins, eicosanoids and neurotransmitters. Previous studies have shown that tuft cells are capable of triggering immune responses in different organs (e.g., intestine and airways) via G protein-coupled receptor-dependent pathways, involving components of chemosensory transduction. Although tuft cells have been detected in salivary glands, their functions in this organ are unknown. The aims of this project are designed to utilize modern technologies to explore tuft cells biology in salivary gland epithelium as well as their role in innate and adaptive immunity. The K99 phase proposes to (1) to investigate tuft cell distribution and function in salivary gland epithelium through advanced microscopic techniques as well as in vivo experiments; (2) to determine tuft cell chemosensory components in salivary gland epithelium using single cell analysis; (3) to determine the effects of tuft cell on salivary gland innate immunity using tuft cell ablation in vivo model. During this time the candidate will complete mentored training in molecular immunology and biology, high-resolution microscopy, single cell RNA sequencing and spatial transcriptomics as well as courses in professional development. The independent R00 phase will investigate the role of tuft cells in salivary gland adaptive immunity utilizing Sjögren’s syndrome-like mouse models and human specimens. Together, the new generated information will allow a better understanding of tuft cell biology in salivary gland and allow therapeutic targets for salivary gland diseases.

NIH Research Projects · FY 2024 · 2023-09

Project Summary Alzheimer’s disease (AD) is the most common form of dementia with hallmarks of extracellular beta amyloid (Aβ) plaques (A), intraneuronal tau tangles (T), and neurodegeneration (N), known as the A/T/N framework, a descriptive classification for AD biomarkers. Accumulating evidence shows that a severely imbalanced microbial community, or dysbiosis, is associated with A/T/N and neuroinflammation in AD patients compared with healthy controls (HC). However, it remains unknown how individual microbiota correlates with regional A/T/N neuroimaging markers in AD and HC. It is also unknown if dysbiosis directly promotes and accelerates A/T/N at early stage and whether there are effective interventions available to mitigate the dysbiosis and thus AD risk. Therefore, the goal of the project is to design a translational study, employing parallel human and preclinical animal experiments to understand mechanism and identify interventions for filling these knowledge gaps. The central hypothesis is that severity of dysbiosis between AD and HC individuals will correlate with their regional A/T/N imaging markers and cognitive status; young healthy triple transgenic AD (3xTg-AD) mice received fecal microbiome transplantation (FMT) from AD patients (FMT-AD) will have reproduced dysbiosis as the donors, which will accelerate A/T/N, neuroinflammation and cognitive impairment of the mice. Interventions with inducible nitric oxide synthase (iNOS) inhibition will mitigate A/T/N and neuroinflammation, and prebiotic diet (inulin) supplementation can further restore microbiome balance to protect brain physiology and cognition. The central hypothesis will be tested by the following three Specific Aims: (1) Identify correlation of dysbiosis, A/T/N imaging markers and cognition in humans; (2) Reveal impact of iNOS on mitigating A/T/N in the presence of dysbiosis; (3) Determine ability of inulin, with and without functional iNOS, to rescue FMT-AD- induced A/T/N and cognitive impairment. Participants who had PET scans for “A/T” will be recruited for the study, and ultrahigh resolution 7T MRI will be used to determine “N”. Translational 7T MRI, gut microbiome sequencing and cognitive assessments will be applied to both humans and mice to determine longitudinal effects of gut-brain interactions. A novel iNOS knockout triple transgenic AD (iNOS-KO/3xTg-AD) mouse model has been created for the project to study the iNOS effects on mitigating A/T/N despite of gut dysbiosis. Biochemical assays and brain staining will be used to determine “A/T” in the mice. Inflammatory gene expression will be identified by transcriptomics. It is anticipated that the findings from this study will have tremendous positive impact as they will enhance the understanding of gut-brain interactions underlying A/T/N in AD and pave the way for future disease-modifying interventions for AD via the microbiome-gut-brain axis. As iNOS inhibitors, inulin diet, 7T MRI and microbiome analyses are available for humans, the success of animal interventional outcomes and the human study pipeline established in the study may pave a way for future clinical trials to mitigate AD risk by gut microbiome modulation.

NIH Research Projects · FY 2024 · 2023-09

Intrauterine growth restriction (IUGR) is associated with perinatal organ injury and the risk of developing cardiovascular, renal, and metabolic disorders in later life. Hence, elucidation of the mechanisms that cause early and progressive organ derangement in growth-restricted newborns is necessary to reduce infant and adult morbidity and mortality. Urotensin II (UII), a potent vasoactive peptide modulates renal function, and its levels are increased in infants with heart and kidney disease. Although its physiological and pathophysiological mechanisms are unresolved, recent evidence suggests that the UII system can promote neurotransmission, thereby altering organ function. Here, we propose a new concept that an increase in UII activity contributes to renal insufficiency in growth-restricted newborns. UII stimulates peripheral sympathoexcitation via Ca2+-dependent tyrosine hydroxylase phosphorylation, catecholamine biosynthesis, and neurotransmission. Sympathetic outflow elicited by UII triggers kidney injury in the neonates. These concepts will be investigated in newborn pigs and a preclinical porcine model of naturally-occurring human asymmetric IUGR. Using innovative procedures for translational research, we will study renal function in small-for-gestational-age neonatal pigs and elucidate the function and regulation of the UII system and the contribution of its components to 1) alterations in neonatal renal hemodynamics and 2) renal insufficiency in growth-restricted infants. We anticipate that our proposed studies will have a significant impact on understanding the pathophysiology of the immature kidney.

NIH Research Projects · FY 2024 · 2023-09

PROJECT SUMMARY Vaccination is perhaps the greatest public health achievement of our time. With an explosion of antibiotic resistance, developing new vaccines against multi-drug resistant (MDR) bacterial pathogens is more important than ever. Pseudomonas aeruginosa (Pa) is an important opportunistic human pathogen that causes severe infections in patients with cystic fibrosis (CF), burns, severe wounds, pneumonia, as well as critically ill patients who require intubation or catheterization. Clearing Pa has become problematic as it has become increasingly antibiotic resistant. This is exacerbated by the fact that the biggest risk factor for negative outcomes associated with MDR Pa is advanced age. After the age of 60, there is a significant increase in morbidity and mortality resulting from MDR Pa. While there are Pa vaccines in development, none are licensed. The goal of the R21 is to define a stable nanoparticle (NP) suspension for our prophylactic Pa vaccine that prevents Pa, regardless of strain, prior to establishment of a biofilm. Like many Gram-negative pathogens, Pa strains of the PAO1/PA14-clades possess a type III secretion system (T3SS) that allows avoidance of host innate immunity and is required for initiating infection. Structurally resembling a molecular syringe with an external needle, the T3SS apparatus (T3SA) provides an energized conduit from the bacterium into the host cell for transporting the effector proteins that mediate key aspects of infection. A needle tip protein and the first of two translocator proteins localize to the distal end of the T3SA needle to mediate host cell contact. In Pa these proteins are PcrV and PopB, respectively, and they are required for pathogenesis. They are also highly conserved (95-98%) among all P. aeruginosa strains that possess a T3SS. We have fused PcrV and PopB to give PaF. To promote simultaneous uptake of antigen and adjuvant by antigen presenting cells, we genetically fused LTA1, the active moiety of dmLT, to the N- terminus of PaF (L-PaF). L-PaF reduces mouse and rat lung Pa burden significantly when challenged with a PAO1/PA14 clade Pa. Recently, Pa outliers of the PAO7 clade have been identified that are devoid of the T3SS and instead use exolysin A (ExlA) to disrupt host cell membranes. We have added ExlA to our L-PaF formulation and, when delivered intranasally, have demonstrated protection against PAO1/14 and PAO7 clades in mice. Sera from these mice exhibit significant opsonophagocytic killing (OPK). Additionally, elevated levels of IL-17 were secreted from lung cells of L-PaF-vaccinated mice. Both IL-17 and OPK are deemed important in clearing Pa infections. In this R21, we will assess the protective immune response of a stable particulate ExlA/L-PaF NP suspension. We will complete this project in two aims: 1) We will generate nanoparticle formulations for the ExlA/L-PaF antigens and assess their stability. 2) We will then determine the immune response(s) elicited by the ExlA/L-PaF nanoparticle formulation(s) and determine their ability to clear Pa from the lungs.

NIH Research Projects · FY 2025 · 2023-09

PROJECT SUMMARY / ABSTRACT Heavy alcohol use is prevalent in the United States and results in significant physical and psychological burden. One in 10 adults in the United States reports binge drinking on a weekly basis, and few are willing to seek mental health treatment. Thus, additional strategies are needed to engage and treat individuals at risk for alcohol-related harm. Half of those who screen positive for hazardous drinking report clinically significant symptoms of insomnia. Insomnia tends to be less stigmatized than other mental health disorders, and it is one condition for which we have highly efficacious treatment. Thus, one potential strategy to engage individuals in mental health treatment and reduce the burden of alcohol use in the United States is to target insomnia. The proposed five-year R01 aims (1) to investigate daily associations between sleep and alcohol use, (2) to examine change in insomnia as a mediator of CBT-I effects on alcohol use outcomes and sex as a moderator of those effects, (3) to identify mechanisms linking change in insomnia to alcohol use outcomes, and (4) to evaluate CBT-I effects on cardiovascular outcomes. Heavy-drinking adults with insomnia will be randomly assigned to Cognitive Behavioral Therapy for Insomnia (CBT-I, n=112) or waitlist control (WLC, n=112). Outcomes will be assessed mid-treatment (after 3 sessions), at the end of the active intervention period (post- treatment), and at 1, 3, and 6 month follow-ups. Primary outcomes include insomnia severity, drinking quantity, and alcohol-related consequences. Data will be analyzed using multilevel models. The results of the proposed research will inform research and clinical practice by determining the extent to which sleep operates as a mechanism of alcohol behavior change. Its innovation lies in evaluation of insomnia not only as a gateway to mental health treatment, but also as a mechanism of improvement in alcohol-related consequences. This is consistent with NIAAA’s strategic plan to evaluate interventions that target sleep.