Johns Hopkins University

NIH Research Projects · FY 2025 · 2022-08

Project Summary / Abstract Purpose: The Rhythm Evaluation for AntiCoagulaTion with Continuous Monitoring of Atrial Fibrillation (REACT AF) clinical trial will compare the efficacy and safety of two treatment strategies for stroke prevention in atrial fibrillation (AF): the current standard of continuous direct oral anticoagulation (DOAC) versus a novel strategy of precision, time-delimited DOAC initiated only in response to a ≥ 1-hour AF episode detected by an AF-sensing smartwatch (AFSW (Apple Watch)). Rationale: Stroke risk is often temporally related to AF onset and duration, but bleeding risk continues as a constant risk of anticoagulation exposure even during long AF-free periods when stroke risk may be low. REACT- AF will evaluate the benefits and risks of withholding anticoagulation during prolonged periods of sinus rhythm as guided by an AFSW. Compared with continuous DOAC, AFSW-guided, time-delimited DOAC treatment may reduce bleeding events while maintaining stroke protection. This has potential to improve important major clinical outcomes and quality of life while reducing health care utilization. Design: REACT-AF is a multicenter prospective, randomized, open label, blinded endpoint (PROBE design) trial comparing the current standard of care of continuous DOAC administration versus time-delimited DOAC treatment guided by an AFSW in patients with a history of paroxysmal or persistent AF and low-to-moderate stroke risk (CHA2DS2-VASc score 1-4). The study will have an initial explanatory phase I followed by an explanatory phase II with pragmatic elements. Primary Aim 1 (Efficacy Objective): To assess whether AFSW-guided, time-delimited DOAC therapy is non- inferior to continuous DOAC therapy for a composite endpoint that includes: (1) Ischemic Stroke; (2) Systemic embolism; (3) All-cause mortality. Hypothesis: Time-delimited DOAC therapy is non-inferior to continuous DOAC therapy for the composite endpoint of ischemic stroke, systemic embolism, and all-cause mortality. Primary Aim 2 (Safety Objective): To assess whether AFSW-guided, time-delimited DOAC therapy significantly reduces major bleeding events compared to continuous DOAC therapy. Hypothesis: Major bleeding events will be significantly lower in participants randomized to AFSW-guided, time- delimited DOAC therapy compared with participants receiving continuous DOAC therapy. Exploratory Aim 1: To compare overall participant satisfaction with anticoagulation management between the two study arms. Exploratory Aim 2: To compare estimates of health-related resource utilization in participants randomized to control versus experimental arms.

NIH Research Projects · FY 2025 · 2022-08

PROJECT SUMMARY Behavioral experiments in humans and primates show that novel visual objects motivate behavior, by capturing attention and gaze, and promoting learning. Abnormalities in novelty seeking are associated with obsessive compulsive disorder, anxiety, depression, anhedonia and autism. But despite the importance of novel objects in our daily life, and the clinical relevance of novelty seeking, we lack an understanding of how primate brain circuits determine whether an object is novel, and how novelty signals control novelty-seeking. Previous studies reported that neurons in many brain areas respond differently to novel stimuli versus familiar stimuli. However, novel stimuli differ from familiar stimuli in many respects. For instance, novel stimuli are unexpected, deviate from recent experiences, and motivate behavior. Such broad and diverse impact of novelty on behavior not only highlights that it is critical to understand the neural mechanisms of novelty seeking, but also illustrates why it has been challenging to dissociate novelty signals from other types of neural signals, and therefore why it has been difficult to isolate how circuits utilize novelty to control motivated behavior. The hypotheses of the Aims are that (i) object novelty controls novelty seeking through a newly discovered anterior ventral medial temporal cortex (AVMTC) to zona incerta circuit, and (ii) single AVMTC neurons acquire novelty selectivity through a quantitatively definable algorithm that considers object recency and object unexpectedness to mediate novelty- related behaviors. Aim 1 will uncover the neural mechanisms that control motivated behavior to explore novel objects. We devised a new behavioral paradigm that measures monkeys’ eagerness to experience novel objects. Preliminary neurophysiological and causal experiments suggest that an understudied subthalamic region, the zona incerta (ZI), controls the motivation to seek and explore novel visual objects, and that this ZI function is distinct from other types of primary reward- and intrinsic- motivated behaviors, such as from the drive to obtain information about uncertain rewards. These assertions will be fully tested by contrasting the novelty functions of ZI with the habenula-dopamine pathway. We will also study how this circuit controls novelty seeking when novelty has extrinsic values (e.g., good or bad) and must be integrated into object valuation. Aim 2 will determine the mechanisms through which novelty responses arise in a wide range of primate brain circuits by recording single neurons’ activity across temporal cortex, amygdala, hippocampus, and the prefrontal cortices with semi chronic high channel count arrays while monkeys participate in a behavioral procedure that will (i) assess the underpinnings of single neurons’ object novelty responses, and will (ii) dissociate novelty responses from signed and unsigned subjective-value and prediction errors. These Aims offer an unprecedented opportunity to understand how the brain mediates the curiosity to approach and explore novel objects, which is a fundamental form of intrinsic motivated behavior that is particularly prominent in primates, and that is dysregulated in many disorders of cognition and mood.

NIH Research Projects · FY 2025 · 2022-08

Project Summary/Abstract: Every year, approximately 550,000 Americans are diagnosed with heart failure. Half of these patients die within 5 years of diagnosis. Several lines of evidence suggest that a post translational modification of proteins, O-GlcNAcylation (OGN), plays a key role in the response of the heart to stress, regulating both health and disease. I discovered chronic exposure to increased OGN causes heart failure, whereas decreased OGN can protect the heart. However, we lack detailed understanding of how OGN contributes to heart health and disease. This gap in knowledge hinders the development of O-GlcNAc-targeted therapies to prevent heart failure. OGN occurs on thousands of proteins in the heart and is regulated by only two enzymes, OGT (adds modification) and OGA (removes modification). Myocardial OGN is increased in failing hearts, but it was unknown if increased OGN was a cause of heart failure. To answer this question, I developed a novel line of transgenic mice overexpressing either OGT, or OGA, in myocardium. OGT hearts have more OGN and these mice have myocardial hypertrophy, heart failure and die prematurely from arrhythmias. In contrast, OGA animals had less OGN and were protected against cardiac stress. My new findings support a role for the Yes Associated Protein (YAP) in causing myocardial hypertrophy in response to excess OGN. The short-term goal of this proposal is to execute complementary research and career development plans to address these gaps in knowledge and position myself as a cardiac O-GlcNAc expert. The long-term goal of this proposal is to use the knowledge gained to facilitate the development of O-GlcNAc targeted therapies for heart failure. Here, I propose to test the specific hypothesis that excess OGN activates YAP and modulates adverse cardiac remodeling through enhanced transcription of pro- hypertrophic genes. The 5-year career development plan proposed here will provide me formal training in four crucial areas: (1) Advanced techniques in glycobiology; (2) advanced training in protein mass spectrometry; (3) proficiency in protein bioinformatics; (4) enhanced grant writing and leadership skills. At the conclusion of this award period, I will have acquired the skills and training necessary to become a leader in the area of cardiac O-GlcNAc biology, an under-explored area of scientific investigation that shows great promise for translation into novel therapies.

NIH Research Projects · FY 2025 · 2022-08

Although there is increasing recognition that the cerebellum is involved in cognition as well as motor function, the manner in which the cerebellum contributes to cognition is uncertain. The cerebellar sequencing hypothesis posits that the cerebellum acquires sequence information, makes sequence predictions, and detects sequence violations via a forward model. Sequencing requirements are prominent in both verbal working memory (VWM) and language acquisition. Although cerebellar activation has been observed in many VWM and language investigations, the brainstem/cerebellar neural correlates of sequencing in cognition, and the influence of cerebellar sequence predictions on neocortical targets, are poorly understood. In Aim 1, we will investigate the cerebellar sequencing hypothesis in VWM. Our preliminary data indicate inferior olive (IO) involvement in sequence acquisition, whereas sequence violations are characterized by large increases in cerebro-cerebellar functional connectivity (FC). We hypothesize that cerebellar ataxia patients, who exhibit gray and white matter degeneration, should exhibit neural and behavioral abnormalities in sequencing- dependent VWM performance. Using fMRI, we hypothesize group differences in IO activation during sequence acquisition and FC between cerebellum and known critical forebrain regions (CFRs) for VWM (left inferior frontal gyrus [LIFG], supplementary motor area, and left temporal/parietal cortex) during sequence violation. Using structural neuroimaging, we predict group differences in cerebellar gray matter and peduncle integrity, as well as in structural connectivity between cerebellum and CFRs. We will correlate these structural and functional measures with task performance to infer brain-behavior relationships. In Aim 2, we will test the generalization of cerebellar sequencing in a statistical learning/language acquisition paradigm. Ataxia and control subjects will receive fMRI during a learning phase in which they listen to a pseudo language to learn transition probabilities of sequences of phonemes, and a test phase in which they will detect phoneme sequence violations. We hypothesize that ataxia patients will be impaired in detecting incorrect sequences or novel transitions of syllables. As in Aim 1, we hypothesize group differences in IO activation during sequence acquisition and changes in FC between cerebellum and known CFRs during sequence violation, but for statistical learning those CFRs are left superior temporal gyrus, striatum, and LIFG. Finally, the cerebellum is hypothesized to provide its sequence prediction computation to neocortical targets, and in Aim 3, using cerebellar transcranial magnetic stimulation (TMS) with concurrent functional MRI, we will test the hypothesis that TMS disruption during a sequencing task will produce greater changes in neocortical activation relative to an analogous control task that does not have the predictive component. These investigations will improve our understanding of cerebellar involvement in cognitive function as well as cognitive abnormalities in patients with cerebellar damage, or with diseases linked to the cerebellum.

NIH Research Projects · FY 2025 · 2022-08

PROJECT SUMMARY The long-term goal of this K23 Career Development Award is to prepare the PI (Rachel Aaron, PhD) for an independent research career that aims to promote adaptive recovery for individuals who survive orthopedic trauma. Orthopedic trauma, resulting in severe injuries such as multiple fractures or amputation, occurs in around 3 million people annually in the United States; about half of survivors experience persistent pain and psychological distress in the year following injury, and most report substantial disability 7 years post trauma. There is an urgent need to identify factors that underlie pain and psychological distress following orthopedic trauma and to develop targeted psychological interventions to treat these potentially disabling symptoms. The broader literature suggests that difficulties with emotion regulation (i.e., identifying one's emotions and engaging in strategies to up- or down-regulate them) and central sensitization (i.e., alterations in the endogenous modulation of pain) lead to poor pain-related outcomes. Using a theory-driven assessment of emotion regulation, and gold-standard, laboratory-based assessment of central sensitization (quantitative sensory testing [QST]), Study 1 will examine emotion regulation difficulties and central sensitization at 6 weeks post trauma as predictors of persistent pain, distress, and opioid use 6 months post trauma. Study 2 will test the feasibility of assessing and delivering Emotional Awareness and Expression Therapy (EAET) to people who endorse persistent pain (i.e., clinically significant pain, present most days for the past 3 months) at 6 months post trauma. EAET is a novel chronic pain psychology intervention that treats pain and distress by targeting trauma-related emotion regulation process. Trauma exposure is ubiquitous among orthopedic trauma survivors; thus, EAET may be ideally suited for those with persistent pain post trauma. However, the feasibility of delivering EAET is unclear due to established barriers engaging this population in mental health treatment. Proposed research and career development activities will take place at Johns Hopkins University (JHU), a renowned research environment. JHU is dedicated to the success of its junior faculty and provides unique access to orthopedic trauma patients. The PI has formed a strong team of content experts in central sensitization (including QST), psychological intervention (including EAET), and orthopedic trauma. Immersed in JHU's rich training environment, the PI will achieve the following career goals through dedicated mentorship, didactic experiences, and professional development opportunities: (1) develop expertise in the assessment of central sensitization, including QST; (2) gain foundational skills for intervention development, implementation, and analysis; and (3) learn to lead impactful orthopedic trauma clinical research. The completion of this K23 proposal will provide the necessary training and preliminary data for the PI to obtain independent grant funding and systematically pursue a line of research to improve outcomes for survivors of orthopedic trauma.

NIH Research Projects · FY 2025 · 2022-08

Novel approaches to reduce the risk of cognitive decline and Alzheimer's disease and related dementias (ADRD) in older adults are urgently needed given the aging of the population. Over the past decade, observational research has implicated peripheral hearing loss as being one of the largest potentially modifiable risk factors for dementia that may account for 8-9% of all dementia cases. Hypothesized pathways underlying this observed association may be modifiable with hearing loss treatment consisting of the use of hearing technologies (e.g., hearing aids) and rehabilitative training. The Aging & Cognitive Health Evaluation in Elders (ACHIEVE) study is an ongoing, NIA-sponsored Phase III RCT (R01AG055426, MPIs: Lin/Coresh) investigating whether hearing loss treatment versus an aging education control intervention reduces cognitive decline over a three-year follow- up period. From 2018-19, we recruited 977 adults ages 70-84 with untreated mild-to-moderate hearing loss who were randomized 1:1 at baseline (Year 0) to receive hearing intervention (HI; best-practice hearing services and technologies) versus a successful aging (SA) education control intervention (i.e., one-on-one sessions with a health educator covering topics important for healthy aging). Participants are currently being followed semiannually at the ACHIEVE field sites with final Year 3 study visits scheduled from 2021-22. After their Year 3 visit, all participants randomized to the SA education control group will also be offered the hearing intervention. Final Year 3 results from this original trial will indicate whether hearing intervention (versus a successful aging control intervention) reduces cognitive decline over a 3-year interval after randomization. We now propose to continue following the ACHIEVE cohort for an additional 3 years (i.e., up to Year 6) to determine the long- term effects of hearing intervention (i.e., participants randomized to HI at Year 0) versus successful aging/delayed HI control (i.e., participants randomized to SA at Year 0 and offered HI after their Year 3 visit) on cognitive and brain outcomes. Given that cognitive impairment typically reflects the slow accumulation of pathologic changes, the benefits of HI in slowing this decline may not be fully appreciable within just 3 years. Therefore, this 6-year follow-up of the cohort will allow us to fully evaluate the longer, cumulative impact of HI on older adults. Such findings will complement the main trial results in 2023 and directly inform clinical and policy decisions around the potential use of hearing interventions to reduce the risk of ADRD. This proposed study has the following aims: Aim 1 To determine the long-term effect of HI versus SA/Delayed HI control on rates of the co-primary outcomes of: (a) cognitive decline and (b) incident mild cognitive impairment (MCI)/dementia. Aim 2 To determine the long-term effect of HI versus SA/Delayed HI control on changes in brain MRI measures of: (a) regional brain volumes and (b) white matter tract integrity. Secondary Aims: 1) To investigate potential factors contributing to HI treatment effect heterogeneity; 2) To investigate health care expenditures and utilization between the HI vs SA/Delayed HI control groups by analyzing Medicare claims data.

NIH Research Projects · FY 2025 · 2022-08

PROJECT SUMMARY/ABSTRACT People with human immunodeficiency virus (HIV), (PWH), are at increased risk of frailty, which increases the risk of adverse age-related outcomes, including falls, hospitalization and mortality. The mechanisms of frailty are not completely understood, particularly among PWH. The objectives of this proposal are to study the extent to which free testosterone and sex hormone binging globulin (SHBG) concentrations are associated with frailty and inflammation in men with HIV. We hypothesize that free testosterone and SHBG are key biomarkers for identifying PWH at the highest risk of frailty and who may benefit from intervention with anabolic agents. Our specific aims are to: 1) Determine the association of circulating free testosterone and SHBG with incident frailty using state-of-the-art hormone measurements among men with HIV, 2) Determine the association of diurnal variation in free testosterone with HIV serostatus in men and its association with systemic inflammation, 3) Determine the association of novel SHBG glycans with frailty among men with HIV. In Aim 1, we will measure serum free testosterone with state-of-the-art methods and SHBG in men with HIV who are part of the Multicenter AIDS Cohort Study (MACS), an ongoing prospective study since 1984 studying the natural and treated histories of HIV-1 infection in homosexual and bisexual men. We will determine the associations of these hormones with incident frailty, collected at semi-annual visits since 2007. In Aim 2, we will select men with and without HIV that have collected blood samples in AM and PM to assess diurnal variation in free testosterone and systemic inflammation [Interleukin 6 (IL6) and soluble TNF-alpha receptors II (sTNFRII)]. In Aim 3, we will study novel SHBG glycoforms in men with HIV, the identification and quantification of SHBG glycoforms will be performed by capillary electrophoresis and lectin microarray. The proposed research aims to provide new insights to the contribution of free testosterone and SHBG in frailty and its relationship with systemic inflammation. The goals during the award period include gaining advanced expertise in biostatistical methods, design and conduct epidemiological studies, as well as hands-on experience in the measurement of glycoforms from plasma proteins and interpretation of glycomic data through mentored research, tailored didactic coursework, and supervised performance of relevant laboratory techniques. Long-term goals include developing a career as an independent investigator in translational epidemiology and developing new approaches to treating and preventing age-related outcomes such as frailty in PWH.

NIH Research Projects · FY 2025 · 2022-08

Project Summary Approximately 280,000 women are expected to be diagnosed with breast cancer in the United States in 2021 and more than 40,000 will die from the disease. It is well documented that early detection results in improved morbidity and mortality. Ultrasound imaging is an important screening and diagnostic breast cancer detection tool, particularly for women with dense breasts when mammography tends to be suboptimal. While suspicious findings may be clarified with ultrasound imaging, a subset of ultrasound images yield inconclusive results, ne- cessitating biopsies or follow-up imaging, which increase patient anxiety and places additional burdens on the time available for clinical care and the resource allocations of our healthcare system. One reason for this out- standing challenge is that dense breasts tend to create images with significant acoustic clutter, which confounds the differentiation of an otherwise anechoic mass (which is indicative of a benign cyst) from a truly hypoechoic mass (which could be indicative of malignancy). In addition, it can be difficult to distinguish a complicated cyst (which has internal echoes due to proteinaceous material and is benign) from either a solid mass or a complex cystic and solid mass (which could be malignant) using standard ultrasound imaging methods alone. The objective of this proposal is to develop new, real-time ultrasound imaging technology that will simplify clin- ical workflows by distinguishing fluid-filled masses from solid masses and from complex cystic and solid masses, which all appear hypoechoic in traditional ultrasound B-mode images. Our novel approach, Robust Short-Lag Spatial Coherence (R-SLSC) imaging, has demonstrated feasibility to make this distinction by incorporating coherence-based beamforming to augment existing beamforming methods available in clinical ultrasound scan- ners. Aim 1 will focus on development of a real-time system for implementing matched B-mode and R-SLSC imaging. Aim 2 will evaluate and compare real-time system performance. Aim 3 will assess the ability of our novel methods to distinguish fluid from solid or complex cystic and solid masses utilizing a combination of quanti- tative analyses and task-oriented reader studies. Aim 4 will investigate advanced methods to retrieve coherence information and diagnostic information regarding mass contents from ultrasound channel data, including recently discovered options that rely on coherence lengths and lag-one coherence values without requiring reader input. Successful completion of these aims will lead to a real-time, ultrasound-based tool to confidently distinguish solid from fluid hypoechoic breast masses and provide a more simplified clinical workflow for the most challenging of these cases. In addition, results from the proposed studies will be applicable to clarifying the content of masses that may appear in multiple organs throughout the human body (e.g., testicular, liver, or pancreatic masses).

NIH Research Projects · FY 2026 · 2022-08

In the US, 4.5 million adults have liver disease, and liver transplantation (LT) is the only curative treatment for those with cirrhosis; transplant centers are charged with determining recipients for a life-saving organ. LT centers assess each patient’s appropriateness for transplant, culminating in a decision to list for transplant or decline. If listed, patients are prioritized based on disease severity and will either receive a liver or be de-listed for a variety of reasons, such as death. While prior research has targeted factors affecting post-listing outcomes (e.g., waitlist dropout, post-LT survival), an upstream focus on factors impacting listing status has not been well studied. LT listing decision-making is variable. Objective clinical measures are utilized, but complex data wrangling requirements and subjectivity permeate data gathering, clinical observations, and psychosocial assessments. A data-driven approach to LT listing has yet to be described. Predictive analytics (supervised machine learning) can be harnessed to strengthen objectivity in complex decision-making. Preliminary data from Dr. Strauss’s qualitative work are the first to comprehensively outline potential pathways related to listing status and reveal that transplant center providers are cautiously optimistic for machine learning-based clinical decision support tools in LT evaluation. The hypothesis is that timely access to summarized, objective data can improve provider decision-making and patient listing. Using a multi-disciplinary approach, Dr. Strauss will leverage her strong relationships with experts from Johns Hopkins Medical Center: experienced transplant team, transplant research lab, Malone Center for Engineering in Healthcare, and School of Public Health. The overarching project goal is to improve LT decision-making using a data-driven and team-based intervention; the overarching training goal is to gain skills in machine learning and implementation science. AIM 1: Develop and internally validate a machine learning-based model to assist LT listing decision-making. AIM 2: Create a data-driven intervention for team decision-making in LT evaluation. AIM 3: Design a multicenter pilot implementation trial of a data-driven intervention for LT evaluation. Impact: Through this project, Dr. Strauss will develop a data-driven intervention that will improve LT listing. This mentored award will develop Dr. Strauss into an R01-funded, independent physician-scientist with advanced skills in machine learning and implementation science.

NIH Research Projects · FY 2026 · 2022-08

PROJECT SUMMARY Age-related loss of muscle mass, or sarcopenia, is a hallmark of aging that affects up to 20% of those over 65 and up to 50% of those over 80, for which there are no pharmacological treatments. We recently discovered that the enzyme Glutamate Carboxypeptidase II (GCPII), which catalyzes the hydrolysis of N-acetylaspartylglutamate (NAAG) to glutamate, is highly upregulated in activated macrophages infiltrating muscle during aging, and that inhibiting the elevated GCPII activity with the inhibitor 2-PMPA (IC50 = 0.3nM) dramatically delays neuromuscular junction (NMJ) denervation, and muscle function and volume loss. Unfortunately, 2-PMPA is not clinically developable. It is highly polar, with negligible oral bioavailability (F<2%), a short half-life (<30m), and is active only with high systemic (IP) doses. Given its significant clinical potential, we propose to address these limitations by utilizing hydroxyl-dendrimers to facilitate its sustained and targeted delivery. Hydroxyl-dendrimers have shown promise as targeted delivery systems due to their size (~4-10 nm) and surface attributes. They are rapidly cleared from circulation under normal conditions but are selectively engulfed and retained by activated and phagocytic immune cells under injury or inflammatory conditions. This is a very translational approach, as targeted dendrimer delivery has been demonstrated to be efficacious in multiple animal models and recently shown to reduce inflammation and mortality in a Ph2 clinical trial in hospitalized patients with severe Covid-19 (NCT04458298). We have assembled a highly experienced team with extensive expertise in neuromuscular disorders and aging (Hoke), dendrimer nanoparticles (Kannan), and animal pharmacology, pharmacokinetics, and clinical translation (Slusher). Together we plan to develop dendrimer-2PMPA (D-2PMPA) for age-related sarcopenia by implementing the following aims: AIM 1. Synthesize and characterize generation 4 (G4) and generation 6 (G6) D-2PMPA conjugates. AIM 2. Assess D-2PMPA (G4 and G6) pharmacokinetics, target engagement, and biodistribution in aged mice. AIM 3. Evaluate the efficacy (behavioral, electrophysiological, and histological) and tolerability of the selected D-2PMPA conjugate in aged mice. Successful execution of these aims will result in a D-2PMPA conjugate ready for IND-enabling studies to support future clinical studies to combat age-related sarcopenia.

NIH Research Projects · FY 2026 · 2022-08

PROJECT SUMMARY Vestibular receptors encode information about head movements and send these signals through the vestibular nerve to the brain stem. In turn, receptors and afferents receive bilateral inputs from cholinergic efferent fibers that originate in the brain stem. To date, the function of the efferent pathway has remained elusive. It has been suggested that efferents might play a role in normal development of vestibular reflexes and compensation after lesions. In particular, efferents mainly affect activity of afferents with calyx terminals that completely cover the basolateral walls of vestibular hair cells, providing a unique form of synapse. Furthermore, in addition to acetylcholine, sources for gamma amino butyric acid (GABA) have also been found in the vestibular periphery, in the supporting cells and probably also in some of the efferent fibers. However, there is little known about the synaptic properties, receptor types, and interaction between cholinergic and GABAergic inputs and their effect on responses of vestibular afferents. The goal of the present proposal is to investigate the underlying mechanisms that mediate changes in afferent response properties by cholinergic and GABAergic inputs. We will use an in vitro whole preparation of the vestibular sensory epithelium to study the effect of specific agonists of different subtypes of receptors on hair cells and afferent terminals in mouse. We will also use an in vivo mouse preparation to record response properties of vestibular nerve afferents along with optical stimulation of cholinergic fibers/ GABAergic cells and application of agonists and antagonists of specific receptors in the inner ear. Finally, we investigate the effect of these drugs on vestibular function in alert mice by measuring the vestibulo-ocular reflex. Results of these studies provide the information to correlate changes at the level of single synapses in the end organs, to vestibular nerve activity, and behavioral responses. The ultimate goal of these studies is to pave the way for finding new treatment options through local application of drugs into the ear to improve vestibular compensation in patients.

NIH Research Projects · FY 2025 · 2022-08

In the United States, women are prioritized in the US national strategy to end the epidemic. Multiple individual, interpersonal, and structural vulnerabilities fuel the HIV epidemic among women, and worsen health conditions (e.g., substance use and mental health disorders). National cohorts are critical to monitoring epidemic trends and how major events (e.g., epidemics, new biomedical interventions) impact HIV and other health conditions. The objective of this proposal is to use a novel, hybrid “community hub”-supported digital cohort (“hub-supported digital cohort”) model to evaluate HIV incidence, risk factors, and health conditions among women in the US (N=3,000). In this model, on-the-ground community “hubs” will support enrollment and retention of a nationwide digital cohort. We will refine optimal digital cohort methods while examining the impact of structural and psychosocial syndemic experiences on HIV incidence and parameterizing mathematical models to identify targets for future multi-level combination HIV prevention interventions. The specific aims are: 1) Determine the efficiency and acceptability of using a novel, hub-supported digital cohort model to enroll and retain a sample of women for HIV research. 2) Estimate the prevalence and characterize patterns of co-occurring health conditions among women. 3) Estimate HIV incidence in women, followed every 6 months for at least 24 months to identify tailored approaches for combination, multi-disciplinary HIV prevention interventions. 3.1) Examine the effect of co-occurring health conditions on HIV incidence among women in the US. 3.2) Characterize the PrEP continuum among women and associations with HIV incidence over time, including uptake of newly emerging formulations, longitudinal patterns of HIV risk and adherence, and the role of co-occurring health conditions in the PrEP continuum PrEP uptake, adherence, and retention. 4.) Develop dynamic models of multi-level combination HIV prevention interventions and scale-up among women to simulate the impact of evaluated interventions on HIV incidence through 2030, corresponding to the National HIV strategy. There is a need to refine and evaluate hybrid digital cohort models with attention to mitigating selection bias and attrition of different populations – an important area of research. Our explicit efforts to develop a hybrid cohort model center on a focus to support research participation across different populations and provide representative and generalizable data. Study findings will provide critical epidemiologic parameters for future HIV prevention research, provide a platform for exploration of other research questions, and inform the development of evidence-based and acceptable HIV interventions to reduce HIV acquisition among women in the US. Public Health Statement Women are highly burdened by the HIV epidemic in the United States. This proposal will use a novel, technology-infused “community hub”-supported digital cohort (“hub-supported digital cohort”) model to evaluate HIV incidence, co-occurring health conditions, and risk factors among women in the US and Puerto Rico. We will refine optimal digital cohort methods, gather 24 months of longitudinal data from women, examine individual and contextual predictors of HIV incidence, and utilize cohort and contextual data to parameterize mathematical models for the identification of effective HIV prevention interventions to change the trajectory of HIV and co-occurring health conditions among women in the US.

NIH Research Projects · FY 2025 · 2022-08

ABSTRACT Nearly one out of five new HIV infections in the United States occurs among cisgender women, with 85% of cases attributed to heterosexual contact. Black women are disproportionately affected, comprising 60% of new HIV infections among women, although they comprise only 14% of the female population. Consistent condom use, daily oral tenofovir disoproxil fumarate 300mg-emtricitabine 200mg (TDF-FTC) as pre-exposure prophylaxis (PrEP), and male partner HIV testing are evidence-based interventions for women to reduce their risk of HIV acquisition. Yet, only 1-6% of women who could benefit from PrEP are prescribed it. Barriers to PrEP uptake are multifactorial. Patient-level barriers to PrEP uptake include women who may not think PrEP is for them, given that the majority of PrEP clinical trials and marketing strategies have targeted men who have sex with men. Also, cisgender women may not perceive themselves as being at risk for HIV. Further exacerbating the discordance between risk perception and actual risk is that women tend to be unaware of their male partners' HIV serostatus and HIV risk factors. Provider-level barriers include difficulty identifying patients at high risk for HIV, discomfort with sexual history taking, and lack of PrEP knowledge. Unfortunately, an accurate HIV risk assessment tool does not exist for U.S. cisgender women and may not ever exist because the HIV incidence in U.S. women is too low to develop it. An alternative evidence-based intervention is desperately needed. We plan to fill this gap by identifying an effective intervention and implementation strategy to increase PrEP uptake in an ObGyn clinical setting (where women receive prenatal care and sexual and reproductive health services). Since TDF-FTC was approved, women have consistently expressed a preference for receiving HIV prevention services in clinics where they receive ObGyn care. Our multi-level (patient and provider-level), multi-component intervention includes EHR data collection and education using multi-media tools. Our central hypothesis is that communicating tailored HIV risk messaging in real-time in a relatable and comprehensive manner to patients and ObGyn providers can increase conversations about HIV prevention. Aim 1A: To determine the most effective intervention and evaluate its implementation in an ObGyn clinical setting. 1B: To identify modifiable contextual factors associated with effective implementation using the RE-AIM framework. Aim 2: To evaluate the cost-effectiveness, return on investment, budget impact, and equity impact of the multi-level intervention components and the implementation strategy. In collaboration with our local government- and a HRSA-funded implementing partner sites, we hope to demonstrate a sustainable and scalable solution to increasing PrEP counseling by ObGyn providers and PrEP uptake by patients.

NIH Research Projects · FY 2025 · 2022-08

Summary The hallmark of cellular senescence is the inability of cells to progress through the cell cycle. With increasing age, senescent cells accumulate in multiple tissues; their abundance increases in aging and several age-related diseases such as atherosclerosis, diabetes, lung disease, and many others. Senescence is both a physiologically fundamental and pathologically relevant program, with its role depending on the context and the specific situation. Evidence linking senescence to common age-associated human diseases has emerged. Despite these advances, little is known about the abundance, spatial distribution, precise nature, and functional relevance of senescent cells in human tissues. The main challenge is paused by the extraordinarily complex heterogeneity of the 3D architecture of tissues like the pancreas, even in non-diseased conditions, which greatly complicates the spatially resolved identification of senescent cells. In this project, we will use the pancreas as a testbed and will expand our 3D spatial analysis of cellular senescence to the human breast and ovaries of similar complex heterogeneity. The development of spatial -omics approaches such as spatial transcriptomics/proteomics may help overcome the challenge paused by 3D tissue heterogeneity. But these approaches only provide high- content molecular information in a spatially resolved manner in 2D tissue sections. Here, we propose to establish a new integrated 3D imaging platform that can map both the 3D architecture of large volumes (> 1cm3) of tissues and can determine the location of senescent cells within a 3D tissue sample. Given its versatility, our proposed integrated platform could readily be used to study spatial senescence in other tissues (besides the pancreas, breast, and ovaries studied here) and to incorporate protein-based and RNA-based senescence signatures that will be discovered by other centers and projects of the SenNet network. To produce the first comprehensive 3D multiscale senescence atlas of tissues across ages, we propose the following aims in the UG3 and the UH3 phases. In the UG3 phase, in a small set of pancreatic and breast tissues, we will first integrate our new AI- based 3D tissue reconstruction platform CODA with immunofluorescence (the CODA+IF platform) for multiple labeling of senescence markers in FFPE tissue samples of non-diseased human pancreas and breast. We will then integrate CODA with DBiT-seq (the CODA+DBiT-seq platform) and apply this integrated platform in regions of the tissue sample that are poor and rich in cellular senescence, as identified by CODA+IF. In the UH3 phase, we will apply these 3D cellular senescence mapping methods to large cohorts of pancreatic, breast, and ovarian tissue. We will measure the distribution and variability and associated molecular signatures of senescent cells within different tissue compartments in non-diseased tissue volumes as a function of age.

NIH Research Projects · FY 2025 · 2022-08

PROJECT SUMMARY DNA methylation is a major epigenetic modification that plays an important role in key biological processes, including genomic imprinting, X-chromosome inactivation, suppression of transposable elements, and carcinogenesis. Although it has been traditionally considered to be restricted to CpG dinucleotides in metazoan genomes, emerging evidence over the past decade has shown that CpH (H=A/C/T) methylation is present in mammalian genomes, including cultured pluripotent stem cells, embryonic stem cells, induced pluripotent stem cells, the mouse germ line, and especially at a relatively high level in human and mouse brains. Given that CpGs only represent 4% of the metazoan genomes, CpH methylation greatly expands the proportion of the genome that is subject to regulation by cytosine methylation and represents a new mechanism of transcriptional regulation. In our previous studies, we generated neuronal DNA methylation profiles at a single base-resolution of the adult mouse dentate gyrus in which 80-90% of the cells are NeuN positive granule neurons, and our team was one of the first to show that ~25% of cytosine methylations are located in the CpH context. Notably, we identified the first mCpH reader, MeCP2, both in vitro and in postmitotic neurons in vivo. In addition, we found that CpH methylation was established postnatally and required DNMT3A for its active maintenance in neurons in vivo. Mutations on both the reader and writer lead to neurodevelopmental disorders, such as fragile X syndrome (FXS), amyotrophic lateral sclerosis (ALS), and Rett syndrome. Loss of either Dnmt3A or MeCP2 in the mouse models causes overlapping and distinct phenotypes in behavioral and molecular tests, suggesting the existence of additional mCpH-binding proteins. We believe that a critical step towards understanding the biological functions of mCpH is to identify its binding proteins. In this proposal, our goal is to identify additional mCpH binding proteins. We hypothesize that mCpH regulates transcription directly or indirectly via recruiting sequence-independent and/or -dependent mCpH-binding proteins in neurons. We will use protein array (Aim 1) and Digital Affinity Profiling via Proximity Ligation (DAPPL; Aim 2) to identify sequence-independent and -dependent mCpH-binding proteins and validate candidates using gel-shift (EMSA), OCTET and luciferase assays in vitro. We will employ a viral in vivo delivery system and high- throughput sequencing technologies to characterize their roles in transcriptional and chromatin regulation in the adult mouse brain (Aim 3). The effectiveness of our strategy will be rigorously evaluated via a series of in vitro and in vivo assays. If funded, the success of this project is expected to provide a rich resource of sequence-dependent and independent mCpH-binding proteins that will lay the foundation to elucidate the roles of CpH methylation in neurons, stem cells and other tissues. The insights into the mechanism of CpH methylation is expected to provide novel drug targets for treating neurodevelopmental disorders.

NIH Research Projects · FY 2025 · 2022-08

Project Summary/Abstract Exosomes are nanoscale vesicles with a diameter of 50-200 nm, actively secreted by various types of cells in our body. As they carry biomolecules (e.g., proteins, RNAs, or metabolites) specific to their parental cells and are easily found in biofluids (e.g., blood or urine), exosomes have emerged as a promising biomarker for the detection and treatment monitoring of various diseases. Also, exosomes have the strong potential as a therapeutic agent for regeneration and immune regulation; for example, exosomes from mesenchymal stem cells (MSCs) have been tested in clinical trials for the treatment of brain injury. However, the fundamental mechanisms of what makes cells secrete exosomes and how the molecular contents in exosomes are determined remain unclear; for example, we have limited information about how to regulate MSCs to maximize the production of their exosomes carrying therapeutic molecules. My Lab aims to address these questions by investigating the role of metabolism in exosome biogenesis, because multiple steps of exosome biogenesis, including vesicle formation inside a cell and fusing into the plasma membrane, are directly associated with metabolic processes. In this Project, we will investigate how the exosome generation rate and molecular contents are determined under different metabolic conditions, specifically with the modulation of nutrients and NAD levels. We will also develop a single exosome sorting technology based on intravesicular proteins and investigate the biogenesis of exosomes with mitochondrial molecules under mitochondrial stress conditions. The research accomplishments from this Project will deepen our understanding of exosomes and help us develop exosome-based diagnostic and therapeutic strategies more effectively. Our long-term research goal is to identify the mechanisms of the interplay between metabolism and biogenesis of extracellular vesicles (EVs). This MIRA research focuses on exosomes, a subpopulation of EVs. Based on our research progresses, we will expand our research scope to other EVs, including microvesicles, in the future.

NIH Research Projects · FY 2025 · 2022-08

PROJECT SUMMARY Older adults with Alzheimer’s disease and related dementias (ADRD) often take multiple medications and use potentially inappropriate medications (PIM), placing them at increased risk of adverse drug events, drug interactions, treatment burden, and mortality. Deprescribing (reducing or stopping medications that are harmful or unlikely to be beneficial) can improve outcomes for people living with dementia (PLWD). The overarching goal of this proposal is to refine and pilot an intervention in which ADRD care partners are identified in primary care and provided with educational materials through the patient portal to engage them in deprescribing for PLWD. We propose a multicomponent intervention, eAlign, which includes: 1) Facilitated patient portal registration for both PLWD and care partners; and 2) delivery of a patient portal intervention to align medication decisions with PLWD and care partners goals, provide care partner training in nonpharmacologic treatment of behavioral and psychological symptoms of dementia, and reduce polypharmacy and PIM use. We propose the following specific aims: In Aim 1, we characterize triadic interactions regarding medication use from two complementary perspectives. In Aim 1a we assess how communication dynamics and characteristics of PLWD and care partners affect uptake of deprescribing recommendations during consultation with a clinical pharmacist. We qualitatively analyze content of 120 audiorecorded visits conducted as part of an ongoing, pharmacist-led deprescribing intervention for PLWD and their care partners in primary care. In Aim 1b we identify individual (PLWD) and contextual (health system, clinic, clinician) factors that affect use of the patient portal for medication management among PLWD by examining uptake and use of the patient portal from date and time-stamped electronic interactions of n=7,500 PLWD receiving primary care in two health systems. In Aim 2, we iteratively refine the eAlign protocol through a user-centered design process involving in-depth interviews with key stakeholders (n=15-20 patient-care partner dyads and 10-15 frontline staff, clinicians, clinical informaticists and health system leaders) at both health care systems. In Aim 3, we will pilot the resultant eAlign protocol with a total of 100 patient-care partner dyads at both health care systems to establish feasibility, acceptability and preliminary efficacy for a future multisite cluster randomized trial. We will conduct a two-group pilot randomized trial to examine feasibility of measuring two primary outcomes (total number of chronic daily medications and rates of PIM prescriptions among PLWD) and one caregiver-reported secondary outcome, the Family Caregiver Medication Administration Hassles Scale. This work will establish the preliminary data, methods, and partnerships to undertake a multisite embedded pragmatic clinical trial of a triadic-based behavioral intervention to promote patient and care partner engagement, foster care that aligns with patients’ values, and promote improved health and well-being outcomes for PLWD and their care partners.

NIH Research Projects · FY 2025 · 2022-08

Summary This proposal aims to understand the effects of HIV on the humoral immune response to hepatitis B by focusing on HBV-specific neutralizing antibodies (NAb), B cell repertoire, and monoclonal antibodies that develop after an acute hepatitis B infection. This proposal will study 185 men (74 HIV+) in the MACS-WIHS Combined Cohort Study who had acute hepatitis B while in follow-up and whose outcome of either natural recovery (n=163) or viral persistence (n=22) was previously determined. The first Aim focuses on comparing the prevalence and magnitude of the anti-HBs NAb responses over 30 months after natural control of an acute HBV infection in people living with and without HIV. We hypothesize that in persons living with HIV (PLWH), the NAb responses will be weaker and less durable than in persons without HIV infection. Decreased durability of NAb responses could contribute to the increased risk of HBV reactivation with HIV infection. In the second Aim, we will tag HBV specific B cells isolated from participants’ specimens obtained during their acute infection period. We will then determine and compare the molecular features of HBV-specific B cell receptors during the acute infection period between those with natural recovery and those who develop chronic hepatitis B. We will also determine the effects of HIV on these molecular features and on frequency of B cells specific for HBV. In the third Aim, we will clone monoclonal antibodies (mAbs) from these HBV-specific B cells and determine the mAbs’ functional characteristics and binding affinities. We expect that the mAbs from persons with natural recovery will bind with higher affinity and neutralize more potently than those who develop chronic infection. We also expect that HIV will decrease the affinity and potency of the mAbs. Innovative aspects of this project include: 1) The unique cohort of a large number of incident HBV infections where both natural recovery and viral persistence occur in prospectively-followed people living with and without HIV infection, 2) The ability to detect NAb responses in plasma from human subjects using the HepG2-NTCP infection model system, and 3) The ability to isolate HBV-specific B cells for ex vivo study. To date, such studies have not been possible explaining why there is little information on NAb responses to HBV obtained directly from infected humans. The results from this proposal will contribute to our understanding of the effects of HIV on the immune response to hepatitis B and could facilitate future research to develop a functional cure for hepatitis B, which is the leading cause of cirrhosis and hepatocellular carcinoma worldwide.

NIH Research Projects · FY 2026 · 2022-08

Abstract The Piwi-interacting RNA (piRNA) pathway promotes animal fertility by protecting the germline genome against mobile DNA elements. Despite this well-established paradigm, several critical gaps remain in our understanding of piRNA mechanisms, including the sexual dimorphism of their biogenesis and downstream gene regulatory functions. We discovered that the ancient SNAPc (or SNPC) transcription complex that transcribes small nuclear RNAs (snRNAs) of the spliceosome has diversified in C. elegans to drive the expression of male- and female- specific piRNAs, in addition to its canonical function in snRNA transcription. In the fly and human, the SNPC holocomplex is composed of SNPC-1, SNPC-3, and SNPC-4 subunits, each encoded by a single gene. In contrast, C. elegans expresses several paralogs of SNPC-1 and SNPC-3 that we propose dictate the specificity of three distinct SNPC complexes. In particular, based on our published and preliminary data, we hypothesize that the SNPC-1 paralogs comprise the primary specificity factors that define the unique functions of each SNPC complex for either snRNA or sex-specific piRNA transcription. In this proposal, we will first investigate how this specificity is achieved by identifying the cis-regulatory elements recognized by each SNPC transcription complex (Aim 1). We will also determine the specificity domains, cofactors, and subcellular assembly of the piRNA and snRNA SNPC complexes (Aim 2). Finally, we will characterize the biological phenotypes of the male and female piRNA mutants and leverage these insights to predict and validate endogenous gene targets of sex-specific piRNAs. Collectively, this research will bridge the gaps in our understanding of sexual dimorphism in piRNA transcription and gene targeting mechanisms that ensure proper germline development and robust reproductive capacity of animals. 1

NIH Research Projects · FY 2025 · 2022-08

PROJECT SUMMARY / ABSTRACT Radiomics, or imaging biomarkers, are an active area of research and development that is increasing in breadth with more widespread access to large, patient image databases. Radiomics models have been applied in a wide range of diagnostics, classification tasks, and disease scoring; with advantages for efficient radiology workflow, reducing errors and highlighting important features, and providing additional information in challenging diagnostic cases. Accuracy of radiomics is dependent on a number of factors. The variability associated with the imaging chain including the particular imaging device/vendor, acquisition protocol, data processing, etc. is undesirable and can have a dramatic effect on a radiomics model’s performance. Successful radiomics models generally require careful data curation and standardization of protocols – often preventing successful or efficient modeling in large aggregations of patient data across institutions, vendors, etc. Moreover, even with careful attention to protocol, many imaging devices, like x-ray computed-tomography CT have patient- and scan-specific image properties that continue to add undesirable variability to a radiomics computation. In this work, we propose a framework for end-to-end modeling of a CT imaging system – integrating radiomics calculations as an explicit stage and imaging system output. This kind of rigorous modeling extends previous efforts to under- stand and control the performance of imaging systems. In this context, the proposed mathematical framework provides not only a mechanism for prediction of radiomics values based on the various system depend- ences that degrade their accuracy; but also informs recovery approaches to estimate the underlying “true” radiomics based on the underlying biology uncorrupted by the particular image properties (noise/resolution) of the patient image. We hypothesize that this new paradigm for radiomics computation will both standardize met- rics and improve quantitation. We will test these hypotheses and apply standardization methods to radiomics for interstitial lung disease (ILD, an application where lung textures provide substantial diagnostic information about the disease) through the following specific aims: Aim 1: Develop a mathematical framework for radiomics standardization, wherein both predictive “forward” models and “inverse” recovery models for ILD radiomics will be developed, characterized, and evaluated. Aim 2: Apply and validate prediction and standardization framework in physical systems using custom phantoms with lung textures and including a series of investiga- tions on well-characterized CT benches and CT scanners from all major vendors. Aim 3: Investigate the impact of standardization on radiomics modeling performance in clinical CT data. A multi-site study will establish the performance of standardized radiomics using the proposed framework in radiomics models for both regional and whole lung characterization. Successful completion of these aims will establish a new paradigm for stand- ardized radiomics computation that is applied and validate in multi-site data. This opens the doors to larger, more diverse imaging datasets and the potential for more efficient recovery of subtle imaging biomarkers.

NIH Research Projects · FY 2025 · 2022-08

Project Summary (Overall) High-grade serous ovarian carcinoma (HGSOC) is the most common histological subtype of epithelial ovarian cancer. The overarching goal of the proposed Biomarker Characterization Center (BCC) is to apply a by- design approach based on biology of HGSOC pathogenesis and unmet clinical needs to identify, verify and prioritize, and validate biomarkers, and to develop them into an in vitro diagnostic multivariate index assay (IVDMIA) with the intended use to capture HGSOC in high-risk women at the early stages including i) precursors, ii) confinement to the ovary/fallopian tube or iii) low-volume diseases in high-risk women (BRCA1/2 carriers). The biomarkers that we propose to discover and validate in this proposal are intended for early detection but not necessarily for screening in general population. The BCC’s capability in advanced data generation technologies, multiplexed target assay development, and bioinformatics/data science will serve as resources for the EDRN. Based on the success of our current EDRN projects, this BCC will continue our on- going biomarker development studies including the validation of candidate biomarkers that we have identified through the current BDL. We propose the following specific aims: 1. To optimize and use novel specimen collection and processing technologies, and an iterative and cumulative process that takes advantage of our newly gained knowledge of the biology in ovarian cancer pathogenesis. BDL 2. To optimize and apply innovative bioinformatics, data sciences, and AI/ML tools that incorporate existing knowledge and data to improve discovery of low frequency biomarkers that with their functionally shared pathways/networks could collectively deliver an improved sensitivity while retaining a high specificity. BDL 3. To further develop and optimize the process for efficient multiplex targeted assay development with respect to analytical performance, throughput, and specimen volume requirement for a broad spectrum of candidate biomarkers using a “fit for purpose” approach. BRL 4. To optimize and apply a by-design approach to translating discoveries into clinical tests. Its application had been critical in the development of two FDA cleared tests by JHU team members for the preoperative assessment of ovarian malignancy risk. BDL/BRL 5. To provide expertise and analytical and data science capabilities to the entire EDRN community. The multi-disciplinary team that we have assembled (molecular cancer biology, pathology, clinical chemistry, mass spectrometry, biostatistics, data science, bioengineering), the unique, novel yet biologically and statistically sound approaches, and our long-standing experience in biomarker research and translating discoveries to FDA cleared clinical tests all together ensure the success of this proposed BCC.

NIH Research Projects · FY 2025 · 2022-08

PROJECT SUMMARY More than 550,000 microsurgery cases are conducted each year in the US to repair tissue following trauma, cancer, or congenital deficiencies via transplantation of tissue from one part of the body to another (free flaps) or reattachment of amputated body parts (replantation). The maintenance of patent vascular anastomoses is critical to the success of any free tissue transfer, and as such, intra- or post- operative thrombosis is the most feared complication for the surgeon and patient, and is the primary cause of free flap failure. Free flap failure can lead to re-operations, extended inpatient stay, potentially-devastating functional and cosmetic morbidity, and increased healthcare costs.3 Despite the advent of improved microsurgical instruments and training programs, literature reports have indicated that anywhere from 6 to up to 25% of microsurgical cases result in re-operation due to thrombosis at the microvascular anastomosis site. In each case, microvascular thrombosis caused by hypercoagulability, blood flow stasis, and vessel wall injury (caused in part by damage to the vessel wall during the surgical procedure, often using non-absorbable sutures) is the primary cause of failure. The use of sutures for microvascular anastomosis and their placement directly at the wound site make them an ideal platform for local, sustained drug delivery (no change in surgical practice and mitigates the risks of systemic drug administration). We hypothesize that local delivery of anti-thrombotic drugs from sutures directly at the site of the anastomosis can reduce the rate of thrombosis while securely and reliably connecting all types of vessels. We describe a novel, highly versatile manufacturing platform capable of producing sutures composed of hundreds of drug-loaded, polymeric nanofibers. Our preliminary data demonstrates manufacture of microsurgical sutures capable of surpassing clinical strength specifications when loaded with a wide range of small molecules. In particular, tacrolimus-eluting sutures demonstrated sustained drug delivery, suitable vascular repair, and safe and significant inhibition of neointimal hyperplasia in comparison to systemic tacrolimus. We believe tacrolimus- eluting sutures may also have potential to prevent post-operative thrombosis, and have identified additional drug classes with potential to inhibit thrombosis via multiple mechanisms. Here, we aim to determine which drug class: anti-coagulant (fondaparinux sodium), anti-platelet (acetylsalicylic acid, clopidogrel), or anti-inflammatory (sirolimus, tacrolimus) provides optimal prevention of thrombosis via local drug delivery, and further optimize formulations and manufacturing parameters to provide optimal drug loading and release. Anti-thrombotic sutures will be evaluated in rat models of microvascular anastomosis thrombosis, and the most promising candidates will be tested for safety, pharmacokinetics, and efficacy in a swine free flap model. If successful, our suture platform could improve outcomes across a range of surgical procedures in microsurgery and beyond.

NIH Research Projects · FY 2024 · 2022-08

Causal questions are at the heart of science. Yet, cognitive biases and logical fallacies are major sources of error in causal research across all disciplines. For decades, most aspiring young scientists, those in post-graduate training as well as experienced practitioners in continuing education have not been formally trained – as opposed to a mentor-focused approach - in the philosophical foundations of research practice, including causal reasoning. Instead, science education is strongly influenced by the prevailing culture of valuing specialized subject matter knowledge over sound education in the first principles of science. The proposed NeuR3o-LOGIC learning unit will emphasize critical thinking on causal questions, illustrated by examples from the neurosciences at the interface of the gut-brain axis, an ostensive topic that every human being can relate to. Inspired by our experiences of ‘teaching science like we do science’ in the R3 Graduate Science Program and the Johns Hopkins Bloomberg School of Public Health, we approach this complex topic from the angle of sound error analysis. Driven by our commitment to the three ‘R’s of good scientific practice – Rigor, Reproducibility, and Responsibility, which inform the R3 Program’s name – the proposed METER project will put the learner into a position to recognize where science can go wrong in the realm of causation. Supported by tangible research examples at the intersection of the gut microbiome and the nervous system, the NeuR3o-LOGIC unit will provide the learner with opportunities to employ a structured error analysis and reduction approach to make connections between fundamental thinking in logic and epistemology and major public health issues such as autism spectrum disorders and other neurological conditions. The proposed work does complement, yet not overlap with existing and ongoing, federally funded projects of educational scholarship on the effectiveness of R3 Program training in ethical decision making and data science skills (NSF-IGE Award #1955062; R25 Award #R25AI159447; administrative supplement on T32 Award #T32AI007417). While the first project year will be focused on the design, production, progress monitoring, and initial quality improvement within the NeuR3o-LOGIC project team, regular communication with CENTER will ensure the alignment of goals and objectives. Years two and three of the proposed project will be dedicated towards structured and coordinated project evaluation and revision activities in close coordination with CENTER, the steering committee, and the network of METER awardees in a collaborative community of practice.

NIH Research Projects · FY 2025 · 2022-08

Project Summary Nucleosomes cover most of the eukaryotic genome and present a barrier for the competent binding of many regulatory proteins that control gene expression. A special set of transcription factors called pioneer factors can bind their target sites on nucleosomal DNA, loosen chromatin, and promote the activity of other chromatin factors and enzymes, leading to nucleosome repositioning and gene activation. Sox2 and Oct4 are pioneer factors that orchestrate changes in cell fate during embryogenesis and adult neurogenesis and are major players in the reprogramming of somatic cells into a pluripotent state. Mutation and deficiency in these proteins are linked to neurological disorders, while their enrichment is tied to cancer. Despite ample studies, little is known about how to Sox2, Oct4 and other pioneer factors exert their pioneering activity at the molecular level. Our goal is to address key unresolved questions about how Sox2 and Oct4 engage with nucleosomes in distinct binding modes and alter the structure and dynamics of nucleosomes, and how these changes affect the downstream action of chromatin modifying and remodeling enzymes. Towards this goal, we propose to integrate chemical probing assays with high-resolution nuclear magnetic resonance (NMR) spectroscopy to obtain site-specific structural and dynamic information about pioneer factor interaction with nucleosomes and the perturbations they elicit in DNA and histones to potentially regulate other factors. In Aim 1, we will utilize in vitro binding assays to characterize distinct binding modes of Sox2 and Oct4 to artificial and natural nucleosomes and their dependence on DNA sequence, co-factor cooperativity, and histone composition. We will also adapt methyl TROSY NMR, suitable for studies of super-large biomolecules, to interrogate the site-specific binding conformation and dynamics of these proteins to select nucleosomes with atomic detail. In Aim 2, we will examine the effect of Sox2 and Oct4 binding in various nucleosome positions on the conformation and accessibility of nucleosomal DNA and the disordered histone tails by using NMR, chemical and enzymatic probing methods sensitive to structural and dynamic perturbations. We will further assess whether Sox2 and Oct4, through direct contact and nucleosome perturbations, stimulate the activity of histone methyltransferase enzymes that are found to collaborate in vivo with these pioneer factors. Finally, in Aim 3, we will adapt our approach to characterize how a methyl-DNA binding protein and proposed pioneer factor Kaiso binds to and alters nucleosomes, providing insight into the recognition and function of epigenetic DNA marks in chromatin regulation. The proposed work will lay the basis for future investigations of other pioneer factors and the role of DNA context, synergistic action, histone variants and epigenetic modifications into pioneer factor-mediated chromatin opening. This will improve our ability to modify pioneer factor function and lead to novel approaches for therapeutic targeting.

NIH Research Projects · FY 2025 · 2022-08

There is substantial need to improve treatment for opioid use disorder (OUD). Buspirone is a mechanistically supported medication with robust preclinical and preliminary clinical support for treating opioid withdrawal and decreasing relapse. Buspirone has the utility to treat both acute and protracted withdrawal periods. We are experts in the measurement, evaluation and treatment of opioid withdrawal symptoms and have recently completed an RCT pilot study (n=16) which provides the initial safety, feasibility, and efficacy data to support a more thorough evaluation of buspirone to mitigate withdrawal when administered as an adjunct to a residential stepwise opioid taper. We propose a rigorous, Phase II, three-group, placebo-controlled double-blind RCT to evaluate the efficacy of buspirone for (1) acute withdrawal as an adjunctive pharmacotherapy to a residential opioid stepwise taper and (2) protracted withdrawal during an outpatient phase following taper completion. During the 12-day residential phase, 100 participants with OUD will be enrolled, stabilized on morphine, undergo a morphine stepwise taper, and complete a post-taper observation period where they will have the opportunity to initiate long-term buprenorphine or extended-release naltrexone. The outpatient phase will take place over the course of a 4-week period and will consist of weekly in-person visits and daily diary reports of their withdrawal and craving severity and anxiety. Individuals with OUD (n=100) will be randomized to one of three groups (1) buspirone during both residential and outpatient phases, (2) buspirone during the residential phase and placebo during the outpatient phase, and (3) placebo during both the residential and outpatient phases. We aim to complete 90 participants (30/group). We will collect measures of withdrawal, craving (acute and tonic), anxiety, medication acceptability, and biochemical measures of opioid use. Primary Aim 1 evaluates the impact of buspirone on acute and protracted withdrawal. We hypothesize participants who receive buspirone during both the residential and outpatient phases of the study will have the lowest overall opioid withdrawal severity. Primary Aim 2 evaluates the impact of buspirone on acute and tonic craving. We hypothesize participants that receive buspirone during both residential and outpatient phases will have the lowest tonic craving and that participants will show significantly lower acute craving when they are actively receiving buspirone. Primary Aim 3 evaluates whether retention and relapse prevention are impacted by buspirone. We hypothesize that buspirone used during a residential opioid taper will increase treatment retention and that buspirone used during the outpatient phase will decrease rates of relapse. Primary Aim 4 evaluates whether buspirone mitigates anxiety during residential and outpatient treatment for opioid use disorder. We hypothesize that buspirone will show modest reductions in anxiety during residential and outpatient treatment. This study will collect the data needed to determine whether buspirone is an effective method for improving treatment outcomes for OUD during acute and protracted opioid withdrawal periods.