Purdue University

NIH Research Projects · FY 2025 · 2024-06

Summary Physical activity has been shown to enhance children's executive function (EF) that is fundamental for reasoning, problem solving, and academic achievement. High-intensity interval training (HIIT), a form of exercise consisting of short intense exercise bouts separated by recovery intervals, has gained considerable attention due to its time-efficiency for increasing physical activity and fitness in an enjoyable and reinforcing manner while generating chronic and acute EF benefits in children. However, none of the existing programs utilized the recovery intervals during HIIT, which typically consist of passive and mindless breaks, despite evidence indicating larger cognitive benefits from exercise combined with cognitively engaging activity. The recovery intervals during HIIT provide an opportunity for mindfulness (MF), a mental exercise of self- awareness and self-regulation that improves EF. Repeated practice on the flexible regulation of attentional focus and bodily movement between mindful recovery and exercise bouts is theoretically sound for maximizing long-term cognitive gains because the added MF activity provides enriched experiences and cognitive challenges that stimulate the development of EF. HIIT and MF also have similar acute benefits to EF yet differential impacts on neuroelectric correlates of conflict processing and updating of mental representation. Thus, HIIT and MF may be complementary as they alter differential functional neural underpinnings of EF. This proposal aims to test the effectiveness of a novel mindful HIIT intervention for improving EF in 10 - 12 years old children. By using two active control interventions delivering HIIT without MF and delivering MF without HIIT as well as a passive control intervention delivering sedentary activities without inducing MF, we will further determine the unique effects of HIIT, MF, and their combination on children's EF. Specifically, this proposal will conduct a 12-week school-based cluster-randomized controlled trial and a laboratory-based acute intervention cross-over trial to investigate the long-term and short-term effects of mindful HIIT intervention on children's EF. Our central hypothesis is that integrating MF into HIIT will generate larger long-term and short-term positive effects on children's EF than MF or HIIT intervention along. Outcomes consistent with our hypotheses will provide novel evidence indicating the effectiveness of chronic and acute engagement in mindful HIIT for enhancing children's EF. The successful completion of this study will serve to guide future randomized controlled trials testing the mechanisms and dose-response associations of the long- term and short-term mindful HIIT interventions with behavioral and neural outcomes of childhood EF. This research agenda will support the development of scalable and sustainable interventions that uses MF technique to maximize the positive impacts of exercise on childhood cognitive and brain development while counteracting many health issues centered around physical inactivity.

NSF Awards · FY 2024 · 2024-06

Autonomous aerial vehicles (AAVs) including drones can solve societal grand challenges such as rapid delivery of medicine and wildfire protection in a completely new way. However, a major technical challenge remains: Today’s AAVs lack the artificial intelligence (AI) needed to safely operate in real-world urban air mobility environments. In such environments, AAVs operate in proximity of urban infrastructures (e.g. buildings), at low altitude, without much regulatory oversight, and under unpredictable conditions such as unexpected weather change or additional vehicles in the field. This 2-day workshop will bring together researchers working in academia, industry labs, and governmental agencies to discuss and refine uses cases and capabilities that are key elements of a research infrastructure designed to support the rapid evolution of advanced air autonomy algorithms and systems. Such an infrastructure is envisioned to enable rapid integration and testing of research community components using a cyber and physical infrastructure that can support both in-person and remote operation. An initial implementation of an AAV research infrastructure is AirTonomy located at Purdue University. The workshop will invite a diverse group of individuals including potential users from academia, representatives of industry partners as well as national, state, and regional governments. Through pre-conference activities and in-person breakout sessions, the workshop participants will identify: 1) research use cases, 2) technical requirements of a large-scale research infrastructure, and 3) concepts for sustainability. After the workshop, a report will be published online, and a task force assembling a lead user community will assist with the finalization of research infrastructure requirements and design. 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 Soft tissue sarcomas (STS) represent less than 1% of human cancers, but result in a greater loss of life per patient compared to that of all cancers. There are more than 70 subtypes of STS, tumors are large (>5cm) at diagnosis, and may involve critical structures (nerves, blood vessels), necessitating multi-modal treatment with wide surgical excision, radiation therapy, and chemotherapy. Treatments can be debilitating, with significant negative impact on quality of life and functional outcome. Despite aggressive treatment, tumor recurrence occurs in 40-50% of patients, and re-treatment with conventional strategies may be impossible. Non-invasive, non- ionizing, non-thermal, image-guided tumor ablation strategies are direly needed. This proposal will focus on histotripsy, a non-ionizing and non-thermal focused ultrasound ablation method that mechanically destroys tissue and preserves critical structures through the precise control of acoustic cavitation with real-time imaging feedback. Recently, our team completed proof-of-concept studies demonstrating that histotripsy can safely and effectively partially ablate naturally-occurring STS in pet dogs. However, limitations in the current histotripsy technology prevent rapid and precise treatment of entire tumors. Furthermore, lack of clinical outcomes of patient safety and long-term tumor control hinders clinical implementation of histotripsy as a treatment strategy for STS. Clinically-useful advances require innovative device development and clinical evaluation in a relevant tumor model. Our team proposes 1) the development of a novel ultra-high rate histotripsy system that overcomes limitations in the current technology and, 2) evaluation of the application of this system as an entire-tumor, stand- alone treatment of STS in pet dogs. STS affecting pet dogs have similar clinical presentation, tumor subtypes, and clinical outcomes, resulting in data with high translatability to humans with STS. Our central hypothesis is that ultra-high rate histotripsy systems and methods can be developed to safely, rapidly, and effectively achieve entire-tumor ablation of STS as a viable alternative to surgical treatment. In Aim 1, our team will investigate and validate ablation efficacy and the optimal histotripsy rate and dose needed for complete ablation. In Aim 2, we will determine the maximum clinical histotripsy ablation volume and evaluate the clinical outcome measures of entire-tumor ablation safety, safety of repeated histotripsy ablations, and long-term tumor response of entire- tumor, stand-alone histotripsy treatment of STS in pet dogs. The results of this study will provide critical clinical outcome data to directly inform human and veterinary clinical trials, accelerating the clinical translation of histotripsy as a treatment strategy for STS, with high potential to extend to the treatment of other tumors.

NIH Research Projects · FY 2026 · 2024-05

Project Summary Mass spectrometry and tandem mass spectrometry have become essential tools in virtually all of the molecular sciences associated with biomedical research. Many questions of interest can be addressed by breaking macromolecules of interest (e.g., proteins) into smaller fragments prior to analysis. However, information inherently present in intact macromolecules and their complexes is lost upon digestion, which has motivated the development of so-called “top-down proteomics” and “native mass spectrometry”. While major advances have been made in both of these areas, significant challenges remain, particularly for high mass heterogenous mixtures. This effort emphasizes novel ion chemistries and novel instrumentation directed to challenges in top- down tandem mass spectrometry of biopolymers and their complexes. Particular emphasis is placed on the attachment of multiply-charged ions to high-mass analyte ions of opposite polarity to facilitate mass measurement, mixture analysis, and structural characterization. The controlled attachment of reagents of known mass and charge can dramatically improve the ‘peak capacity’ of a mass spectrometry measurement applied to complex mixtures of ions derived from electrospray ionization. Furthermore, ion attachment, in conjunction with MSn workflows, may prove to be useful in revealing the surface exposure of components in a complex. Novel ion/ion reactions involving superacid anions may also prove to be useful as gas-phase means for the selective removal of metal ions that become incorporated in bio-complexes ionized under native conditions. This effort also involves instrument development aimed at supporting high mass-to-charge ion manipulation (e.g., digital ion trap operation for ion isolation and ion parking of high mass-to-charge ions) and measurement (digital ion trap operation and electrostatic ion trap mass analysis) to support multiply-charged ion attachment experiments. The effort will extend the utility of mass spectrometry and tandem mass spectrometry in top-down biopolymer characterization as well as in the mass measurement and characterization of large complexes, such as molecular machines and viruses.

NIH Research Projects · FY 2025 · 2024-04

PROJECT SUMMARY The goal of this K99/R00 project is to provide training to independence and enable the PI to test the hypothesis that maternal-fetal exposures to environmental contaminants during early stages of fetal brain development render the mature nervous system more susceptible to Alzheimer’s Disease and related dementia (ADRD). Pregnant women are exposed to a large number of environmental contaminants in their daily life. Though the placental-fetal barrier protects the fetus from most harm, some chemicals cross the barrier and can negatively impact fetal development. The ‘Developmental Origins of Health and Disease’ hypothesis states that developmental exposures are a trigger for life-long persistent effects, increasing the risk and susceptibility to later-life age-related neurodegenerative diseases such as ADRD. These early-life exposures could permanently change the homeostatic state of the nervous system in a way that seemingly retains normal structural development but persistently alters function and disease-risk. We propose to develop an in vitro placental barrier linked to human induced pluripotent stem cells (hiPSCs) developing into forebrain neurons. The PI will assess whether exposures found in cord blood can cross this in vitro barrier using mass spectrometry. Then, we will study whether selected compounds (heavy metal, pesticide, plasticizer) induce a persistently altered homeostatic state in developing neurons at early age using imaging techniques as well as assessment of functional outcomes (through micro-electrode array recordings) and genetic and metabolic outcomes (using single-cell RNA sequencing). Finally, the PI will combine both models and develop an integrated placental-barrier – forebrain model and expose to selected compounds. Exposed cultures will be matured and persistency will be assessed again. Findings will be compared between different culture ages and different classes of compounds to develop persistency signatures and get better understanding on how different classes of compounds induce this neurological health risk state. Completing this study will advance the PI’s training in important new directions that are enabled by the expertise of their mentors and collaborators and will help the PI reach their goal of becoming an independent scientist. The team of mentors and collaborators is composed of experts in the following fields of: placental biology and barrier modelling, exposomics, physiology of healthy brain aging, bioinformatics and statistics, and neuro(epi)genetics. In collaboration with mentors, the PI will develop critical skills that are required for a successful transition into a position as independent academic researcher in neuro- and reproductive toxicology. This training will be accomplished through a focused development plan consisting of didactic courses, close collaboration with mentors and collaborators. At the conclusion of this proposal, the PI will have developed a human stem cell derived forebrain model to study persistent neurotoxic effects of trans- placental developmental exposures to environmental pollutants.

NIH Research Projects · FY 2025 · 2024-04

Colorectal cancer (CRC) is one of the leading causes of cancer death, but there is no effective treatment for the late-stage cancer. Early detection with colonoscopy appeared to lower CRC risk but not associated death. To reduce cancer mortality, it is important to develop effective agents for inhibiting high-risk CRC in people with cancer driver mutations and adenomas. Although inhibition of cyclooxygenases (COX-1/-2) by NSAIDs including aspirin have been recognized for preventing CRC, long-term use of NSAIDs is limited due to side effects and moderate anticancer efficacy. It is therefore necessary to search for alternative and improved preventive strategies and agents. Research has shown that pro-inflammatory 5-lipoxygenase (5-LOX) promotes colon cancer development and may be a target for inhibiting CRC. Further, nuclear factor (NF)-κB and JAK-STAT3 are known to contribute to inflammation and promotion of CRC. Importantly, we and others have shown that γ- and δ-tocotrienol (γTE, δTE), which are members in the vitamin E family, inhibit 5-LOX activity, NF-κB and STAT3 activation and the growth of cancer cells. δTE-13’-COOH, a metabolite of δTE, has been shown to be a unique inhibitor of COXs and 5-LOX. In agreement with these findings, a δTE/γTE (8/1) mixture and δTE-13’-COOH have been reported to inhibit chemically-induced colon cancer in mice. Based on these observations, we hypothesize that δTE/γTE and δTE-13’-COOH are novel and effective preventive agents against CRC. Despite existing evidence supporting our hypothesis, there are key knowledge gaps hindering translation of the use of these promising agents to the clinic. In particular, the anticancer effects of these compounds have not been examined in a “human-like” CRC model. The objective of this application is to delineate the anticancer effects and mechanisms of δTE/γTE and δTE-13’-COOH in an innovative CRC model (AKC), which like CRC patients, has mutant Apc and Kras and spontaneously develop adenoma tumors in the large intestine. Significance: The success of this study will develop new cancer-preventive agents, generate preliminary data for R01 application to further validate these compounds for CRC prevention, and offer key preclinical data for translation of basic research to the clinic.

NIH Research Projects · FY 2026 · 2024-04

ABSTRACT The development of the cochlear implant (CI) has revolutionized the treatment of severe hearing loss. Despite its overall success, not every patient who receives a CI will benefit from this technology. The limitation lies not within the technology itself, but primarily within the high level of diversity in the population of people who qualify for CI surgery. Each CI recipient has a distinct hearing-loss profile and clinical background, which imparts unique deafness-induced changes to each level of their auditory system, including the brain. Currently, it is unclear how individual differences within the cortical auditory system, specifically in speech-evoked brain activity, contribute to individual variability in CI speech-recognition outcomes. One reason for this gap in knowledge is that the electromagnetic signals emitted from a CI can disrupt traditional neuroimaging methods. A new optical neuroimaging tool, functional near-infrared spectroscopy (fNIRS), offers a CI-compatible imaging option that is non-invasive and unaffected by electromagnetic artifact. The knowledge gained from recent fNIRS investigations has not yet translated into clinical practice because results are often only reported at the group level; the reliability of fNIRS measurements remains somewhat poor on the single-subject level. The proposed research addresses this issue of reliability by controlling for the interference from systemic physiological signals in single-subject fNIRS recordings. In Aim 1, we will determine the contribution of naturally occurring, non-neural physiological signals to the within-subject variability in fNIRS recordings using systemic physiology augmented fNIRS (SPA-fNIRS). In Aim 2, we will determine the relationship between CI speech-recognition ability and speech-evoked brain activity measured via SPA-fNIRS using naturalistic connected speech signals. This investigation will use an individualized approach to examine cortical-speech processing in adult CI recipients. The findings from this proposal have the potential to reveal underlying sources of individual variability in CI recipients due to differences in their cortical processing of speech. The use of novel connected-speech passages to elicit brain activity in individual CI users will increase the ecological validity of our approach, which is an important step toward translating research findings into clinical practice. Our proposal aims to improve the tools used to objectively measure speech-evoked brain activity in single subjects so that personalized auditory-rehabilitation training can be prescribed to help individuals engage more effective speech-processing strategies.

NIH Research Projects · FY 2025 · 2024-03

Project Summary Oxidative stress contributes to the development and progression of ocular diseases including cataracts, glaucoma, age-related macular degeneration, and diabetic retinopathy. One carbon metabolism influences the response to oxidative stress via antioxidant biosynthesis; however, this pathway is also perturbed upon oxidative stress in the Drosophila eye. One explanation for the observed dysregulation of one carbon metabolism under oxidative stress is because of oxidative modifications on the key enzyme, Adenosylhomocysteinase (Ahcy). Ahcy is a highly conserved enzyme and is solely responsible for the hydrolysis of S-adenosylhomocysteine (SAH) into adenosine and homocysteine in all higher eukaryotes. Upon inducing oxidative stress in Drosophila cells and eyes, Ahcy becomes oxidized at cysteine residue 195 (C195) correlating with increased SAH. This is important because increases in SAH can inhibit methylation reactions and alter the epigenome; however, the mechanism by which oxidative stress perturbs one carbon metabolism is unknown. Based on these data, I hypothesize that redox modifications at C195 inhibit Ahcy activity under oxidative stress leading to increased SAH and a decreased methylation capacity resulting in changes in gene expression. In the proposed studies, I will employ in vitro assays, biochemical, genome-wide sequencing, and genetic manipulation studies to elucidate if Ahcy is redox regulated and if it serves as a neuroprotective mechanism against retinal degeneration. In aim I, I will determine if C195 is the only (or major) oxidized cysteine, determine the type of oxidative modification, characterize the impact of C195 oxidation on enzymatic activity of Ahcy using a novel DESI-MS approach, and test if C195 mutations regulate Ahcy enzymatic function in vivo. In aim II, I will identify genes regulated by Ahcy, test if the genetic downregulation of Ahcy alleviates blue light induced retinal damage, and identify the genomic loci directly bound by Ahcy. Along with the experiments planned in these aims, I will obtain expertise in recombinant protein purification, enzymatic assay development and characterization, and proficiency in large- scale dataset bioinformatic analyses. These skillsets will be an asset for my future career goal of entering the pharmaceutical industry. Overall, this proposal will elucidate the regulation mechanism of Ahcy and may lay the foundation for future studies to develop targeted therapies to delay or prevent the onset ocular disease.

NIH Research Projects · FY 2024 · 2024-03

Diabetes mellitus (DM) is a global health challenge that affects nearly 463 million people worldwide. Type 1 diabetes (T1D) accounts for 5-10% of all diabetes cases and is increasing at a rate of 2-6% annually. Recent research has challenged the dogma that all β cells are eventually destroyed in type 1 diabetes (T1D). Emerging data suggest that some cells in long- duration disease may be protected from autoimmunity owing to the acquisition of a ‘de- differentiated' phenotype that makes them less visible to the immune system. However, a consensus definition and the precise phenotype of a de-differentiated cell has yet to be established. Moreover, the heterogeneity of such a phenotype between single cells within and between islets and persons with T1D is not clear. Using single molecule Fluorescence In-situ Hybridization, our preliminary data has revealed significant heterogeneity of the spatial transcriptome in cells. This project will utilize the newly emerging tools such as computer vision and artificial intelligence, to deepen the exploration of the FISH images of human pancreatic tissues. We will develop computational tools and bioinformatics strategies to understand the spatial distribution of the transcriptome in T1D β cell phenotypes. (1) Develop computational tools to process, analyze, and quantify multiplexed transcriptomic images and proteomic images of pancreatic tissue from human organ donors. (2) Identify representative features of RNA expression in β cell phenotypes in long-duration T1D and during T1D evolution with bioinformatics strategies. Clarifying the molecular phenotype of persistent cells in long-duration disease could have important implications for T1D therapeutics, and it has the potential to inform the development of disease modifying interventions aimed at improving the function of these cells.

NIH Research Projects · FY 2026 · 2024-03

PROJECT SUMMARY/ABSTRACT Glaucoma, which is often referred to as the "silent thief of sight," gradually steals vision without early warning signs or pain, and it remains the leading cause of blindness worldwide. Currently, the only known method to slow the progression of glaucoma is to reduce intraocular pressure (IOP), which helps to minimize permanent damage to the optic nerve. However, IOP levels can fluctuate over both daily and seasonal periods, with the greatest peaks often occurring during sleep or in a supine position. In turn, vision loss may occur during sleep, without the patient being aware of it, even if their IOP levels are normal during daytime measurements taken in clinical or home settings. Assessing the 24-hour pattern of IOP on a regular basis, daily, weekly, and monthly can be highly beneficial for patients with glaucoma or those who are at risk of developing the condition, which is however lacking in standard clinical practice. Although wearable ocular tonometers, such as the Triggerfish lens (Sensimed, Inc.), aim to continuously monitor IOP in both clinical and home settings, their long-term use in human eyes is currently limited, particularly during sleep, due to various side effects such as foreign body sensation, eye pain, superficial punctate keratitis, corneal epithelial defects, and conjunctival erythema. To address this unmet need, we propose to develop and optimize a unique class of smart soft contact lenses that build upon existing commercial brands of soft contact lenses, without altering their intrinsic properties, including lens power, biocompatibility, softness, transparency, wettability, oxygen transmissibility, and overnight wearability. We anticipate that the smart soft contact lenses will offer a number of advantages over existing wearable ocular tonometers, including superior safety, user comfort, lens fit, visual field, ease of use, overnight wearability, and measurement accuracy. To this end, we will produce various prototypes of the smart soft contact lenses and then iteratively conduct a comprehensive set of in vitro, ex vivo, and in vivo tests to assess several key features. These include: (1) durability against perpetual cycles of mechanical loads such as flipping, folding, and stretching, chemical treatments such as cleaning and disinfecting, and other possible user mishandling such as dehydration, overheating, or overcooling; (2) in vitro cell viability on human corneal cells; (3) ex vivo sensing performance in enucleated pig eyes; (4) in vivo sensing performance in dogs (without euthanasia); and (5) clinical validity in human eyes, both in-clinic and at-home settings. We will compare the measurement results with those obtained from the in-clinic, portable, and wearable types of current ocular tonometers such as the Goldmann applanation tonometry (GAT), I-Care Home (I-Care, Inc.), and Triggerfish lens (Sensimed, Inc.). We envision the smart soft contact lenses to provide continuous, 24-hour monitoring of IOP that is well-tolerated by the majority of glaucoma patients and those suspected to have the condition. Successful outcomes of this project may also present opportunities to broaden the use of smart soft contact lenses beyond glaucoma management, opening the door to the continuous monitoring of other chronic ocular diseases, such as cataract and age-related macular degeneration.

NIH Research Projects · FY 2026 · 2024-03

Abstract. Most biological processes require the production and degradation of cellular proteins. Maintaining a balanced protein homeostasis (proteostasis) is therefore essential to cellular fitness. Furthermore, lapses in proteostasis have been linked to the molecular basis of a wide variety of genetic diseases. Nevertheless, our understanding of how the cell buffers adaptive swings in proteostasis and how this is perturbed by mutations remains incomplete. This is especially true for integral membrane proteins (MPs), which account for a quarter of the proteome and include most drug targets. The production of folded, functional, and properly localized MPs is both inefficient and sensitive to the effects of mutations that promote misfolding. The net efficiency of this process is established by the interactions that nascent MPs form with chaperones that mediate quality control. Most MPs form interactions with an array of QC proteins in the endoplasmic reticulum (ER) that establish the balance between the degradation of immature protein and the export of mature protein from the secretory pathway. We recently demonstrated that this balance is highly sensitive to the propensity of nascent MPs to adopt alternative topologies with respect to the membrane. We found that mutations that promote these defects impact MP expression and ligand binding in a manner that shapes both MP evolution and the molecular basis of disease. Furthermore, we also found that the mechanical forces generated by formation of alternative topologies can alter the outcomes of ribosomal protein synthesis. However, it remains unclear how certain topologies are selectively recognized by molecular chaperones and how these interactions ultimately shape MP biosynthesis and degradation. In the following, we outline innovative approaches to identify specific conformational defects that promote the interaction of nascent MPs with various molecular chaperones including the ER membrane protein complex and calnexin- two mechanistically distinct intramembrane chaperones. By combining CRISPR with deep mutational scanning (DMS), we will determine which classes of mutations and their associated conformational defects promote interactions with these chaperones and how this ultimately shapes mutational tolerance. Additionally, we will build on our recent discoveries to gain insights into how these cotranslational processes impact the fidelity membrane protein biosynthesis itself. We describe the discovery of a novel ribosomal frameshift site within the CFTR transcript and provide evidence suggesting this motif selectively terminates translation of a common misfolded variant responsible for most cases of cystic fibrosis (ΔF508). These findings point to a novel role of ribosomal frameshifting in the regulation of membrane protein homeostasis. We outline ongoing efforts to identify factors that modulate this regulation and to discover and characterize comparable motifs in other disease linked MPs including the voltage-gated potassium channel KCNQ1. Together, our findings will provide mechanistic insights into the regulation of membrane protein biosynthesis and quality control as well as how these constraints factor into the molecular basis of proteostatic diseases of MP misfolding.

NIH Research Projects · FY 2026 · 2024-01

ABSTRACT Aphasia is a disorder marked by impairments in language and cognition. There is substantial variability in how well people with aphasia (PWA) respond to treatment. This variability stems from aphasia treatment programs primarily focusing on language, which is problematic since experimental models indicate that treatment response in aphasia is predicted by pre-treatment language and cognitive measures. Aphasia treatment programs therefore need to address PWA’s cognitive deficits in addition to their language deficits. Attention is one aspect of cognition that is a prime target for aphasia treatment efforts because it is a foundational process that supports other cognitive functions. Attention is also an important prognostic indicator of recovery from aphasia. Yet, attention is rarely assessed in PWA due to a lack of appropriate assessment tools. The Attention Network Test (ANT) is one promising tool because it can measure three types of attention (alerting, orienting, executive control) using one task in 5-10 minutes. To date, the ANT has primarily been used to measure visuospatial attention. However, it is more critical to assess auditory attention than visual attention in PWA because the neural resources that support auditory attention are more left lateralized than visual attention, meaning the left hemisphere strokes which cause aphasia, likely cause greater deficits in auditory attention than visual attention. Auditory attention is also a stronger predictor of language abilities than visual attention. While auditory versions of the ANT exist, our preliminary work indicates that they are inappropriate to use with PWA and/or do not assess the aspects of auditory attention involved in language. In Aim 1, we will use the knowledge gained from our preliminary work to further develop the auditory ANT for use with PWA. We will optimize the auditory ANT by combining task relevant (information that needs to be consciously processed to complete the task) and irrelevant information (conscious processing is not needed for task completion) into a single stimulus. Our pilot data indicates that this approach is feasible, and that the proposed auditory ANT measures alerting, orienting, and executive control as we expect in controls. In Aim 2, we will establish the test-retest reliability, criterion validity, and internal consistency of the auditory ANT in PWA and controls. In Aim 3, we will predict PWA and controls’ language production and comprehension abilities from their alerting, orienting, and executive control abilities. This proposal will produce a psychometrically sound assessment of auditory attention for use with PWA. The results of this proposal also lay the foundation for future work that will use this auditory ANT to predict language recovery in post-stroke aphasia.

NSF Awards · FY 2024 · 2024-01

Energy efficiency is a daunting challenge in embedded systems that run on limited energy budgets. Better performance, longer battery life, and smaller environmental footprints - improving energy efficiency will be the key enabler of applications and services that have not been possible in the past. Approximate computing has recently emerged as a promising approach to the energy-efficient computing of intrinsically error-tolerant applications like image processing, where small deviations from the exact results in the underlying computations do not substantially degrade the resulting application-level quality. For such applications, approximate computing can produce "just good enough" results to save energy at the cost of only minor or no quality loss. This project will develop design methodologies for taking advantage of approximate computing in embedded systems, where the contribution of non-computing subsystems (e.g., sensors, actuators, user interfaces, and network interfaces) to energy consumption is at least as significant as that of computing subsystems (e.g., microcontrollers and memory). In embedded systems, both computing and non-computing subsystems must be holistically considered to take full advantage of approximate computing and accomplish full-system energy quality and scalability. The project scope includes characterization, optimization, and design toolchain development, with the focus on embedded systems design. 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 · 2024-01

Neurodegenerative disease is an emerging public health crisis with Alzheimer’s disease (AD) being the 6th leading cause of death that affects 6.7M patients in the US alone. To date, no curative agents have been identified, and commonly prescribed therapeutics (donepezil, memantine) remediate symptoms, but are wholly ineffective at treating the underlying condition. Contemporary literature suggests that the build-up of neurotoxic kynurenine pathway (KP) metabolites might promote AD pathogenesis. One such neurotoxic KP metabolite, quinolinic acid (QUIN), agonizes the N-methyl-D-aspartate (NMDA) receptor and exerts broad-spectrum neurotoxicity, particularly in the hippocampus and striatum. Notably, neurodegeneration of the hippocampus is a hallmark of AD dementia. As such, regulation of QUIN biosynthesis offers an attractive approach to the treatment of AD. In the proposed research, we aim to regulate QUIN biosynthesis within the CNS by targeting the tryptophan 2,3-dioxygenase enzyme (TDO). TDO is a tetrameric heme-dependent enzyme responsible for the rate-determining first step of the KP. Rather than target the heme-dependent TDO active site, we aim to target a non-catalytic binding site that plays a critical role in the stability of the active tetramer. The central hypothesis of the proposed research is that small molecule-mediated destabilization of this non-catalytic site constitutes a novel approach to the regulation of neurotoxic KP metabolites, and thus a novel approach to the treatment of AD. We will test this hypothesis through two complementary aims. Aim 1 will utilize computational modeling and chemical synthesis to deliver non-catalytic site-selective small molecule degraders of TDO. Aim 2 will assess the therapeutic viability of compounds generated in aim 1 through a series of biochemical assays. Specifically, the TDO degrading effects of each compound will be measured via an ELISA assay, quantitative KP metabolite profiling, and isothermal calorimetry. The pharmacokinetic profiles of select compounds will be assessed via MDCK and microsomal stability assays. Together, these aims will deliver CNS-penetrant TDO degraders and characterize their pharmacological effects on the propagation of neurotoxic KP metabolites. The ligands identified could serve as valuable tool compounds for follow-up studies in translational neuroscience to interrogate the role of KP metabolites in AD pathogenesis.

NIH Research Projects · FY 2026 · 2024-01

Per- and polyfluoroalkyl substances (PFAS) are widespread environmental contaminants that have been investigated as developmental toxicants, with little information on long-term neurotoxicity and clinical outcomes. Our preliminary data suggest that PFAS may produce neurotransmission changes relevant to psychiatric disorders involving abnormal reward processing, specifically anhedonia. We will test the hypothesis that: early life PFAS exposure will produce alterations in reward processing mediated through specific neurotransmission targets. Importantly, the hypothesis will be tested in animal models and humans, utilizing innovative translational approaches. We will test our hypothesis through 3 aims. Aim 1 will establish a brain - specific translational PFAS dosing regimen in mice, based upon published and preliminary data from human brain samples and sentinel animal studies. Here, we will develop a translational dosing strategy, specific to brain levels that is expected to considerably increase the human health relevance of these and future studies. This aim sets the stage for studies on the potential role of PFAS exposures in psychiatric disorders. Aim 2 will determine if PFAS exposure produces alterations in behavioral phenotypes relevant to reward processing in mice. In light of our preliminary data and the gap in the literature, there is a critical need to evaluate developmental neurotoxicity in higher order species. We will assess the emergence of neurological phenotypes through neurobehavioral analyses, neurotransmitter measurements, neuropathology studies, and determination of the biochemical underpinnings of a reward processing phenotype. Aim 3 will determine whether serum PFAS (individual compounds or as a mixture) are linked to human reward processing deficits. To achieve bi- directional translation, we will conduct human studies informed by our animal data. Conversely, data from this aim will inform ongoing animal studies. To identify links to psychiatric disorders, we will conduct a cross- sectional study of adults aged 18 to 30 years. In this study we will: identify correlations between serum PFAS, self-reported anhedonia severity, and clinician-rated anhedonia severity; test for clinical specificity by examining correlations with broader symptoms of depression, mania, and psychosis; and identify correlations between serum PFAS and neurophysiological measures of reward sensitivity, which may represent intermediate phenotypes with disease relevance. Our findings may suggest that individuals with high PFAS levels be carefully monitored for the emergence of psychiatric symptoms. We expect this project to have a significant impact on the understating of environment influences of neuropsychiatric diseases. For the first time, we will establish whether specific PFAS exposures may influence the etiology of reward processing disorders. We will do so in both animal models and human studies – where resultant data from each line of research informs each other to achieve bidirectional translation with respect to experimental design and interpretation.

NSF Awards · FY 2023 · 2023-10

This Faculty Early Career Development (CAREER) project will focus on creating new methods to model, estimate, and control the movement of legged robots for enabling stable locomotion on dynamic rigid surfaces (DRS) (i.e., surfaces that move and do not deform). While today’s legged robot systems have demonstrated remarkable capabilities in traversing stationary surfaces (e.g., stairs, sand, and grass), legged locomotion on DRS (e.g., ships, aircraft, and trains) is a new robot functionality that has not been addressed. This new functionality will empower legged robots to negotiate complex, dynamic human environments (that are prohibitively challenging for wheeled or tracked robots) to allow them to aid in numerous critical high-risk applications, such as shipboard firefighting and fire suppression and cleaning/disinfection of public transportation vehicles to contain the spread of infectious diseases. Enabling such functionality demands reliable robot estimation and control, which are substantially challenging due to the high complexity of the associated robot behaviors that are hybrid (involving continuous leg-swinging motions and discrete foot-landing events) and subject to the time-varying DRS movement. The CAREER research program seeks to solve these fundamental problems and lay a foundation for the development of next-generation legged robot systems capable of autonomous navigation on nonstationary surfaces. The CAREER education program will enhance the robotics curriculum at the University of Massachusetts Lowell while engaging diverse groups, including underrepresented undergraduate and graduate students, K-12 students, and the general public, in robotics education and research. The research goal of the project is to draw upon dynamic modeling, state estimation, feedback control, and theory of hybrid systems to advance the control theory of legged robots in order to realize provably stable legged locomotion on a DRS. To achieve the research goal, four main objectives will be pursued: (i) formulation of a physics-based model that captures the hybrid, time-varying robot dynamics associated with legged locomotion on a DRS; (ii) creation of new methods of designing state estimators that achieve real-time state estimation with convergence guarantees by provably expanding an invariant filtering methodology from continuous systems to hybrid dynamical systems that include legged robots moving on a DRS; (iii) derivation of a Lyapunov-based controller design methodology to produce stable locomotion on a DRS by handling the hybrid, time-varying robot dynamics under uncertainties that reside in both continuous phases and discrete events; and (iv) integration of the modeling, state estimation, and controller design into a model-based framework that provably sustains legged locomotion on a DRS. The project will support the PI to solve major robotics challenges beyond the capabilities of the state of the art, and help establish a long-term career in robotics and control. This project is supported by the cross-directorate Foundational Research in Robotics program, jointly managed and funded by the Directorates for Engineering (ENG) and Computer and Information Science and Engineering (CISE). 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 2025 · 2023-09

Coming with the new century, integration of computer technology into medical practice has enabled scientists to collect massive volumes of electronic health records (EHR) and, in the meantime, deep learning has been developed as the major tool of massive data analysis. However, the EHR data are heterogeneous [varied much for different groups of patients] and fragmented [consisting of a high proportion of missing values], which poses a significant barrier to the applicability and generalizability of current deep neural networks. This project aims to build a health prediction system based on a new type of stochastic neural network (StoNet) with massive, heterogeneous, and fragmented data, while considering integration of the omics, imaging and EHR data in training the system. The StoNet is formulated as a composition of many simple regressions; it is asymptotically equivalent to the deep neural network (DNN) in function approximation as the training sample size becomes large, but its structure is more flexible for dealing with the complexity of EHR data. The StoNet is trained by an adaptive stochastic gradient Markov chain Monte Carlo (MCMC) algorithm. By leveraging on the flexible structure of the StoNet and the sophisticated adaptive stochastic gradient MCMC algorithm, this project provides a rigorous statistical framework for deep learning with massive, heterogeneous and fragmented EHR data. We show that the StoNet forms a bridge from linear models to deep learning, enabling many of the theory and methods developed for linear models to be transferred to deep learning. In particular, we show the sparse learning theory developed for linear models with the Lasso penalty can be transferred to the StonNet, leading to an innovative consistent sparse deep learning method; we address the data heterogeneity issue by replacing each regression of the first hidden layer of the StoNet by a mixture regression; and we address the missing data issue by training the StoNet with an adaptive stochastic gradient MCMC algorithm where the missing data are imputed as for a linear model with multiple imputation methods. The Markovian structure of the StoNet enables the network parameters to be locally learned with fragmented data and leads to an innovative way for nonlinear sufficient dimension reduction of high-dimensional data, facilitating integration of different types of data in StoNet training. We also show the prediction uncertainty of the StoNet can be easily quantified with a recursive application of Eve's law.

NIH Research Projects · FY 2025 · 2023-09

PROJECT SUMMARY Cell division underlies the development of humans from embryos to full-grown adults, regenerative processes such as wound healing, and diseases such as cancer. While much is known about the intracellular aspects of mammalian cell division, less is known about the extracellular aspects of cell division. In many physiological contexts, cells divide in mechanically confining microenvironments, including dense extracellular matrices (ECMs) and growing tumors. Cell division requires extensive morphological changes, including significant growth during the G1 phase of the cell cycle and elongation along the mitotic axis during mitosis, or mitotic elongation. Both growth and mitotic elongation are strictly required for successful cell division. A mechanically confining microenvironment provides a physical barrier to both cell growth and mitotic elongation, and cells must overcome this confinement for successful cell division. Our recent studies have shown that single dividing cells in three- dimensional (3D) matrices generate protrusive forces along the mitotic axis to drive mitotic elongation via a combination of interpolar spindle elongation and cytokinetic ring contraction. We have also found that cell growth during the G1 phase is mediated by outward force generation. However, it remains unclear how these forces and their underlying mechanisms adapt to confining microenvironments with a wide range of stiffness and viscoelasticity. In this project, we will determine how cells tune extracellular forces to sustain cell division in highly confining microenvironments, using a powerful combination of rigorous agent-based modeling and experiments with engineered biomaterials for 3D cell culture. We hypothesize that in microenvironments with increased confinement, i) protrusive activity increases to make space and activate mechanosensitive channels for driving G1 phase cell growth via increased osmotic pressure, and ii) enhanced cytokinetic ring contraction drives mitotic elongation. The main hypothesis will be tested by pursuing the following three aims: (1) Determine how mitotic elongation of isolated cells within highly confining microenvironments is accomplished via a novel force feedback mechanism; (2) Define how isolated cells achieve G1 phase cell growth in highly confining microenvironments; and (3) Establish how growth and mitotic elongation of cells in growing spheroids induce overall expansion of spheroids in highly confining microenvironments. The proposed research project is significant because it will reveal how cells modulate their force generation, to drive cell growth and mitotic elongation for cell division in physiologically relevant microenvironments, and also elucidate the role of matrix remodeling and multicellular cooperation in cell division. The approach is innovative because of i) the development and use of agent-based models that can rigorously capture the most important aspects of cell growth, mitotic elongation, and confining microenvironments with complex rheological properties, ii) the focus on extracellular aspects of cell division, iii) the role of matrix viscoelasticity in cell division, and iv) the examination of the physical basis for spheroid growth.

NIH Research Projects · FY 2025 · 2023-09

PROJECT SUMMARY Impaired tendon biomechanical function reduces mobility and quality of life for the majority of the ~30 million Americans with diabetes, resulting in a substantial economic burden to these individuals and society. Any new approach to enhancing tendon function in people with diabetes is hindered by a poor understanding of the underlying etiology of impaired tendon biomechanical properties. Critically, the role that various serum factors play in the development of tendon complications in individuals with diabetes remains unclear. Our multidisciplinary research team hypothesizes that increased serum advanced glycation end-products (AGEs), with subsequent activation of receptors for AGEs (RAGE), is a principal mechanism driving tendon complications with diabetes. Specifically, activation of RAGE impairs tenocyte function resulting in loss of collagen fibril organization and subsequent impairment of biomechanical function. AGEs accumulate in the serum of patients with diabetes. Our preliminary cell culture work shows that treating tendon-derived cells with AGEs, which cannot form collagen crosslinks, adversely affects critical aspects of tendon ECM maintenance. We have also found that AGEs promote an environment favoring tendon ECM degradation. Utilizing human subjects, we demonstrate that increasing serum AGE concentrations are associated with declining tendon biomechanical properties (e.g., modulus). Serum AGEs can interact with RAGE to promote inflammation and oxidative stress, but such a connection to changes in tendon ECM organization and biomechanical function impairment has not been established. This project aims to 1) delineate the role of serum AGEs and activation of RAGE in promoting tendon ECM disorganization and impairment of biomechanical properties and 2) determine the relationship of serum AGEs to in vivo tendon biomechanical properties and in vivo indicators of tendon collagen fibril organization. Filling these gaps will promote new approaches for improving tendon function and reducing this challenging clinical condition's economic and social burden. Using a mouse model with an inducible RAGE deletion and a model of type 2 diabetes, we will assess the effects of chronically elevated serum AGEs on tendon ECM organization and biomechanical function and the involvement of RAGE in this process. We will use novel ultrasound and magnetic resonance imaging (MRI) methods to determine the relationships between serum AGE concentrations, in vivo tendon modulus, and MRI indicators of tendon ECM organization. We expect this work to show that AGEs via RAGE signaling are a principal mechanism driving changes in tendon ECM and subsequent reduction in biomechanical function in patients with diabetes. Defining the role of serum AGEs and RAGE signaling in the development of the diabetic tendon phenotype will provide an avenue to evaluate novel treatment approaches to reduce the impact of tendon complications in patients with diabetes. Our proposal fits NIAMS's mission of developing treatment strategies for tendon-related injuries. Our project addresses NIDDK’s mission of developing strategies to prevent and treat complications of diabetes.

NIH Research Projects · FY 2025 · 2023-09

Advanced age is a major risk factor for many chronic diseases, including Alzheimer’s disease (AD). Despite substantial research progress, most treatments currently available merely mitigate symptoms. Given that most of patients with dementia due to AD are sporadic, and in those, aging is the key risk factor for this late-onset AD, targeting the mechanisms that have been collectively summarized as “hallmarks of aging” may provide avenues for development of new therapeutic approaches. Emerging evidence links aging and age-related neurodegenerative diseases to disruption in RNA alterations, specifically N6-methyladenosine (m6A) modification. m6A RNA is the most prevalent and abundant modification of RNA in eukaryotes, with high expression specifically in the brain. Recently, m6A RNA has been shown to regulate stability of R-loops; three- nucleic acid structures, consisting of an RNA-DNA hybrid and a ssDNA that form during transcription. In this proposal we will examine the role of m6A epi-transcriptomic modification in R-loop-driven pathophysiology of AD. Using Drosophila AD model, in aim 1 we will elucidate how m6A RNA impairment impacts R-loop distribution across the genome and formation of RNA-DNA hybrids in cytoplasm, and their impact on transcriptional stress and activation of chronic immune response in AD. The significance of aim 2 is in identifying the regulatory mechanisms of R-loop-dependent DSB formation in AD. While variety of exogenous factors can contribute to DNA damage, we will define a role of R-loops in genome instability associated with AD. Moreover, we will define the epigenetic modifications associated with formation of stable R-loops resistant to resolution, which are alternatively processed into DSBs. In aim 3, we will expand our studies from Drosophila to mammalian system. Using in vitro rat cortical neuron cultures seeded with human brain tau, we will further elucidate the molecular mechanisms of R-loop associated genome instability and neuroinflammation in AD. Neurons have specialized RNA metabolism and it is therefore not surprising that dysfunction in RNA metabolism is strongly associated with neurological diseases. This proposal focuses on a novel possibility that defects in RNA metabolism, and particularly R-loop homeostasis, is a significant driver of transcriptional stress, genome instability, and chronic immune response; key hallmarks of aging, whose acceleration may lead to neurodegeneration.

NIH Research Projects · FY 2025 · 2023-09

PROJECT SUMMARY (See instructions): Menthol, cooling/ice, and tobacco flavors are among the most abundant for Electronic Nicotine Delivery Systems (ENDS) or electronic cigarettes. These flavors are not regulated due to the potential public health benefit cessation of combustible tobacco use. However, the toxicological effects of vaping these products are not entirely understood. Further, increased use of cooling/ice/menthol-like products is correlated with higher e-cig consumption due to their cooling and antitussive properties. However, the modified risk and toxicity of these products are poorly understood. The K99 /R00 proposal aimed at identifying the chemical agents (flavoring chemicals) that cause lung toxicity using cell culture and mouse models. As the K99 phase provided biologically significant data from acute exposures, we will continue the same aims as below with a modified R00 plan mainly focusing on sub-chronic (in vitro) and chronic (in vivo) exposures mentioned in Aims 2 and 3. The R00 phase will focus on validating the toxicants identified in the aerosols and relating them to the biological response and biomarkers. Moreover, these findings will be validating during prolonged exposures to flavored ENDS and chemical agents. This study hypothesizes that menthol/cooling flavors and tobacco flavors contain harmful chemicals that induce adverse cellular and biological responses and chemically interact upon aerosolization, causing augmented toxicity with preexisting respiratory conditions. Aim 1: Identify the chemistry of menthol, menthol-like (cooling), and tobacco flavors, including flavoring chemicals and secondary products formed upon aerosolization. Aim 2: Determine in vitro and in vivo toxicity and health effects of menthol, menthol-like (cooling), and tobaccoflavored ENDS in EpiAirway 3D tissues and mice (C57BL/6J and BALB/C) under normal and pre-existing respiratory conditions. Aim 3: Determine in vitro and in vivo toxicity and health effects of menthol, menthollike (cooling), and tobacco flavoring chemicals in EpiAirway 3D tissues and mice (C57BL/6J and BALB/C) under normal and pre-existing respiratory conditions. In R00 phase, effects in lung after sub chronic and chronic exposure to CS and then switching over to ENDS (menthol, cooling, and tobacco) will also be determined, allowing to assess the benefit or the modified toxicity of switching from CS to ENDS. This will further be studied in normal, asthma, and COPD, 3D tissues (sub chronic) and mice with the same phenotypes. Thus, Dr. Muthumalage, in his R00 proposes to perform a comparative toxicity, and biomarkers of disease under normal and pre-existing respiratory disease conditions providing information necessary for regulation of harmful constituents in these products.

NIH Research Projects · FY 2024 · 2023-09

ABSTRACT The audiogram is the cornerstone of clinical hearing assessment, but individual differences in speech perception, especially in noisy environments, cannot be explained by audibility alone. People with normal hearing thresholds often complain of difficulty understanding speech-in-noise, and listeners with sensorineural hearing loss (SNHL) show significant variability in speech perception, even when audibility is restored. Animal models of SNHL and temporal bone histology suggest that peripheral pathology missed by the audiogram may explain some of this variance. Outer hair cell (OHC) dysfunction elevates hearing thresholds, but inner hair cell (IHC) and auditory nerve (AN) dysfunction may be hidden from the audiogram despite their impact on neural encoding of sound. The presence of specific cochlear pathologies and their relative contribution to perception, however, cannot be directly tested in humans. Instead, non-invasive biomarkers of pathology are used. Though diagnostics have been developed for identifying hidden pathologies in people with normal hearing, an individual metric is unlikely to be enough when SNHL results from a combination of peripheral dysfunctions. To address this gap, we use a battery of non-invasive diagnostic tools to determine a biomarker profile for individual subjects and assess its relationship to cochlear anatomy and speech-in-noise perception when there are varying degrees of OHC and non-OHC dysfunctions. This proposal tests our central hypothesis that identifying subtypes of SNHL from integration of biomarkers sensitive to both OHC and non-OHC pathologies significantly improves prediction of suprathreshold hearing over the audiogram alone. Using a cross-species approach, three synergistic specific aims test our hypothesis. First, we assess the differences in biomarker profiles of two chinchilla models of distinct SNHL subtypes, OHC-only hearing loss and complex SNHL (e.g., a combination of OHC, IHC, and AN dysfunction), to measure the effect of non-OHC pathologies when they co-occur with OHC dysfunction. Second, we measure physiological biomarker profiles in humans with SNHL and test whether they better predict speech understanding than the audiogram. Third, using our coordinated physiological test battery as a link between species, we make predictions about the underlying cochlear pathology distributions in humans with complex SNHL based on our histology from chinchillas with known exposures. Whether our hypotheses are supported or refuted, this cross-species dataset will advance our understanding of the factors important for everyday communication and establish a quantitative framework for developing more detailed diagnostic profiles. Greater diagnostic precision that recognizes the multifactorial physiological underpinnings of SNHL will support personalization of hearing healthcare and treatment, especially pharmaceutical interventions for hearing loss. Additionally, the quantitative, cross-species, and professional training received through completion of these aims complements my clinical training in audiology and will be foundational to my career as a translational auditory neuroscientist.

NIH Research Projects · FY 2026 · 2023-09

Abstract Cystic fibrosis (CF) is a lethal genetic disease that currently affects ~100,000 people worldwide. CF is caused by a spectrum of loss-of-function mutations that compromise the biogenesis and/ or function of the cystic fibrosis transmembrane conductance regulator (CFTR) ion channel, most of which enhance its misfolding and degradation. Recent drug discovery efforts have yielded a suite of approved small molecule “correctors” that enhance the expression of misfolded CFTR variants and “potentiators” that restore conductance to CFTR variants with defective gating. Combinations of these molecules have recently revolutionized the treatment of the ~90% of CF patients bearing at least one copy of the well-studied ΔF508 CFTR variant, which is highly penetrant among Caucasians. However, the efficacy of current combinatorial therapies varies widely among the ~10% of patients bearing diverse combinations of rare, uncharacterized CF variants with divergent pharmacological properties (“theratype”). Efforts to expand the labels of current therapeutics and maximize the number of treatable CF genotypes, in particular amongst non-white populations, are constrained by the large number of CF variants and the limited throughput of current methods. Identifying rare CF variants that respond to therapeutic cocktails is likely to become even more challenging as new correctors and/ or potentiators gain approval. Addressing this challenge requires new techniques that enable efficient biochemical and/ or pharmacological profiling of rare CF variants. In the following, we propose to address this challenge with a unique fusion of emerging genetic, biochemical, and computational methods. We show how deep mutational scanning (DMS) can be used to compare the effects of correctors on the expression of hundreds of variants in parallel. Our preliminary findings provide an unprecedented glimpse of the divergent theratypes of CF variants while identifying numerous variants with unique biochemical and/ or pharmacological properties. We first propose to expand on these investigations in order to measure the response of the complete set of CFTR2 missense variants to a panel of structurally diverse corrector molecules. We will then characterize the interactomes of variants with distinct corrector responses to identify CFTR interactions that antagonize the effects of these small molecules. We will then fuse CRISPR/ Cas9 technology with DMS to determine how these interactions impact the spectrum of CF variant theratypes. Using state-of-the-art structural modeling approaches, we will then identify structural defects in the CFTR protein that are associated with the formation of antagonistic interactions and deviations in CFTR variant theratype. We will then utilize machine learning to classify CF variants based on their observed pharmacological properties. Finally, we will assess the effects of approved correctors on the functional properties of previously uncharacterized variants using industry-standard short-circuit current analysis in Fischer Rat Thyroid and human airway epithelial cells. Together, these investigations will help expand the list of treatable CF genotypes and provide new tools to optimize the targeting of CF drugs.

NIH Research Projects · FY 2024 · 2023-09

Sleep, breathing, hemodynamic oscillations, and cerebrospinal fluid movements – Building toward a novel treatment approach for Alzheimer's disease Sleep deficiencies/problems are common in Alzheimer's disease with several hypothesized connections to the movement of cerebral spinal fluid (CSF) in the brain. For example, within Alzheimer's disease the accumulation of beta-amyloid and tau proteins may reflect inefficiencies in neuro-metabolic waste clearance during sleep (a glymphatic system process that is intricately linked with CSF movement). Within neurodegenerative research, the circulation of CSF has hypothesized links to several biological/physiological processes (e.g., sleep, hemodynamic oscillations, breathing); however, we are limited in our understanding of how to potentially improve CSF movement and neuro-metabolic waste clearance to ultimately slow the progression of Alzheimer's disease. The present study fills these critical gaps by (1) quantifying sleep-coupled CSF movement and (2) documenting how CSF movement is coupled with other (more easily assessed and manipulated) biological signals (i.e., hemodynamic oscillations, breathing). The overarching goals of this line of work are to improve our understanding of CSF movement and how this knowledge can be leveraged to slow the progression of Alzheimer's disease. Unlike blood circulation, CSF has no `engine' to drive its flow; therefore, changes in cerebral blood volume (CBV) likely serve as a `driver' of CSF movement. Previous research demonstrates that increases in CBV can be neuronally driven (e.g., sleep); arterial pulsation driven; or breath driven (e.g., meditation/guided breathing). However, we do not understand the magnitude of these changes/couplings. Improving CSF movement/circulation for individuals with Alzheimer's disease has the potential to slow the pathology progression and could prolong higher quality of life for the millions of Americans currently diagnosed.  Aim 1: Assess the degree of coupling between cerebral blood volume (CBV) and cerebral spinal fluid (CSF) movement during wake and sleep states.  Aim 2: Assess the relative contributions of breathing oscillations on CBV and CSF fluctuations during wake and sleep states.

NIH Research Projects · FY 2024 · 2023-09

Project Summary Buprenorphine has been proven as an important therapy in helping patients overcome opioid addition and in preventing overdose. Past usage of BUP has been shown to be both extremely safe and effective. Unfortunately, one of the major problems with all medication assisted treatment is noncompliance. To combat this issue, additional longer acting biodegradable systems must be develop to deliver BUP for longer durations than currently available. With the basis of this program supporting the discovery and development of medications to prevent and treat opioid use disorders and overdose, rapid advancement towards a viable product for new dose regimens and ease of administration for increased adherence should be one of the first, scientifically sound, and robust choices moving forward. PLGA-based drug delivery systems have been used successfully in a number of small molecule products and are the most widely utilized and studied biocompatible polymer systems in controlled release to date. Therefore, the regulatory and development hurdles with the FDA will be ‘lower’ than with other novel excipients or technologies. The goal of this research and product development plan is to perform a pilot pharmacokinetic clinical trial in healthy volunteers. Our preliminary data indicates a biodegradable rod formulation can be fabricated with release profiles similar to that of Probuphine®, and will be optimized over the duration of this project. The Specific Aim of this project is to develop and optimize a biodegradable BUP rod formulation that provides therapeutic kinetics for ≥3 months. The Milestones for the UG3 phase are: (i) Illustrate the critical process parameters and material attributes that dictate the in vitro release kinetics of a ≥3-month; (ii) Successful demonstration of ≥3-month in vivo pharmacokinetics in the dog model from a single biodegradable BUP rod (iii) Confirmation of regulatory requirement and pathway through a preIND meeting with the FDA; and for the UH3 phase are: (iv) Successfully transfer the formulation and manufacturing of the ≥3-month candidate formulation a demonstrated through in vivo studies in the dog model, (v) Completion of GLP local tolerance study (if required by FDA), (vi) IND submission and clearance from the FDA, and (vii) Demonstrate ≥3-month pharmacokinetics above the Cmin and below the Cmax in healthy volunteers. The innovation in this technology is the ability to control the BUP release kinetics in a biodegradable format while minimizing the initial burst; based on our mechanistic understanding of the PLGA microparticle formation process, using PLGAs with specific molecular properties, and providing tight control over the manufacturing conditions. Utilizing extrusion, biodegradable polymer, and compression will enable readily technical transferability as these processes are already heavily utilized in the pharmaceutical industry, allowing for a seamless transition from academia to industry. Furthermore, extrusion-based processes are already scaled in that it is a continuous process, and PLGA-based formulations have previously have been shown to be safe based on the approximate 20 FDA approved products currently on the market. The significance of this research and product development is the final outcome of this project will ultimately provide a new, readily viable, essential tool to help patients overcome opioid use disorder.