Digital Commons Network^™

An Exploration Into Network Analyses Of Motor Behavior, Brain-Computer Interface Control, Arousal States, And An Ischemic Lesion Model, Shashank Anand

McKelvey School of Engineering Graduate Student Theses & Dissertations

Network-level modelling of neural function incorporates activity in specific brain regions along with a measure of the interactions between these regions (“connectivity”). Connectivity can be assessed through several means, for example through tractography (structural connectivity) or correlated temporal evolution of neural activity (functional connectivity). These analyses have provided valuable insight into several aspects of brain function, such as top-down control, memory, and navigation. This work focuses on studying neural activity within and between several brain regions across different brain states: namely, during motor actions, sensory perception, brain-computer interface engagement, task-free fluctuations in arousal state, and ischemic injury. High gamma (70-170 …

Lifestyle Intervention Therapy Modulates Global Dna Methylation And Adipogenic Gene Expression In Severely Obese Hypogonadal Men, Siresha Bathina, Virginia Fuenmayor Lopez, Mia Prado, Salina Biene Teo, Dennis T Villareal, Rui Chen, Clifford Qualls, Reina Armamento-Villareal

Faculty, Staff and Students Publications

Background/Objectives: Previous studies have suggested that lifestyle intervention (LSI) therapies involving diet and exercise can modulate DNA methylation; however, whether this occurs in severely obese hypogonadal men undergoing weight loss from diet and exercise remains unclear.

Methods: In this study, we investigated the effects of weight loss from diet and exercise on global DNA methylation as well as on the mRNA expression of specific demethylation enzymes, DNMT1, DNMT3A, and DNMT3B—in peripheral blood mononuclear cells (PBMCs) and DNA methylation markers in DNA of severely obese hypogonadal men. This is a secondary analysis of samples of severely obese (body …

Energetic Heterogeneity In Retinal Ganglion Cells: Role Of Neuronal Activity And Implications For Resilience, Zelun Wang

Arts & Sciences Graduate Student Theses and Dissertations

Retinal ganglion cells (RGCs) form the only connection between the eye and the brain via their axons in the optic nerve. In diseases such as glaucoma, RGCs undergo irreversible neurodegeneration leading to vision loss. RGCs consist of multiple types differing in morphology, gene expression, and signaling properties. Moreover, these types exhibit differential survival after axon injury. What cellular properties vary between RGC types that could underlie their heterogeneous response to neurodegeneration? Given that energy metabolism is tightly optimized for the homeostatic and active functions of different neurons, physiologically distinct RGC types likely exhibit divergent energetic characteristics. Furthermore, energy metabolism is …

Pkmζ-Kibra Interactions, Molecular Turnover, And Memory, Changchi Hsieh, David A Cano, Panayiotis Tsokas, James E Cottrell, André Antonio Fenton, Harel Shouval, Todd Charlton Sacktor

Faculty, Staff and Student Publications

How can the molecules that strengthen synaptic connections maintain memory in the face of molecular turnover? Our previous work showed that persistent interaction between the postsynaptic scaffolding protein, KIBRA, and the autonomously active PKC isoform, PKMζ, is crucial for maintaining synaptic long-term potentiation (LTP) and memory lasting at least a month. This duration is longer than the lifespans of individual KIBRA and PKMζ molecules. Biophysical modeling of the interaction suggests oligomers of KIBRA-PKMζ dimers, but not individual dimers or monomers, can overcome molecular turnover by continuously incorporating newly synthesized KIBRA and PKMζ, replacing those that have degraded. Here we used …

In Vivo Hsc Gene Therapy Enables Sustained Ecd4-Ig Expression For Siv Prevention, Chang Li, Anna K Anderson, Anne-Sophie Kuhlmann, Veronica Nelson, Audrey Germond, Hongjie Wang, Aphrodite Georgakopoulou, Sucheol Gil, Jasmin Martinez-Reyes, Andrew Riker, Shruthi Shankar Raman, Jiho Kim, Philip Ng, Donna Palmer, Michael D Alpert, Nickolas Skamangas, Charles Bailey, Tianling Ou, Christine M Fennessey, Michael Farzan, Keith R Jerome, Brandon F Keele, Hans-Peter Kiem, André Lieber, John K Bui

Faculty, Staff and Students Publications

We aim to develop an in vivo hematopoietic stem cell (HSC) gene therapy approach for the prevention and control of HIV-1 infection. Toward this goal, we engineered helper-dependent adenovirus (HDAd) 6/3+ vectors to directly transduce HSCs in vivo, enabling progeny cells to secrete eCD4-Ig, a decoy protein that broadly neutralizes HIV/simian immunodeficiency virus (SIV) isolates by mimicking the primary viral receptor CD4 and coreceptors such as CCR5. In rhesus macaques, the HDAd 6/3+ platform achieved long-term expression of an enhanced eCD4-Ig variant (“eCD4-Ig-Emm06”) that retained potent neutralization efficacy in vivo. Transduced HSCs differentiated into lymphoid and myeloid lineages …

Investigating Corollaries Between Streptococcus Gallolyticus Subsp. Gallolyticus Virulence And Colorectal Cancer, Tyler G. Myers

Pursuit - The Journal of Undergraduate Research at The University of Tennessee

Streptococcus gallolyticus subsp. gallolyticus (Sgg) is a gram-positive, non-beta-hemolytic bacterium that belongs to the Lancefield group D of streptococcal pathogens. For the past several decades, associations between Sgg bacteremia and colorectal cancer (CRC) have been apparent, with gastroenterologists routinely recommending colonoscopies for positive cases of Sgg in either blood or stool samples. However, current research has not wholly established whether Sgg acts as a causative agent of CRC or if pre-existing cancers make the lumen of the colon more hospitable to its colonization. Regardless, Sgg has been implicated in the modulation of host inflammatory pathways and subsequent remodeling …

Underexplored Maternal Microbiomes: Immune, Metabolic, And Microbial Pathways Shaping Pregnancy Outcomes, Rafael Tomoya Michita, Nicole Jimenez, Melissa M Herbst-Kralovetz, Indira U Mysorekar

Faculty, Staff and Students Publications

Maternal microbial ecosystems play critical roles in shaping reproductive physiology and pregnancy outcomes. During the pre-conception and prenatal periods, these communities modulate maternal physiology by regulating immune tolerance, nutrient metabolism, and susceptibility to pregnancy complications such as preterm birth, hypertensive disorders, and gestational diabetes. While the gut microbiota has been extensively studied, the roles of cervicovaginal, urinary, respiratory, oral, and upper reproductive tract microbiomes remain less clear. In this minireview, we synthesize current knowledge on these underexplored maternal microbiomes, with an emphasis on the cervicovaginal and urinary microbiota and their interactions with the placenta and fetus. We discuss cross-niche microbial …

Dual Phagocytosis-Checkpoint Blockade Revitalizes Immune Surveillance In Mouse Models Of Glioblastoma, Jonghoon Ha, Yifan Wang, Yifan Ma, Annette Wu, Shiyan Dong, Seong Dong Jeong, Jared L Edwards, Mengyu Chang, Yen-Tzu Chang, Xiaotian Wang, Maurice Dufilho, Michelle Najarro Torres, Shannon Mccabe, Weiye Deng, Adam J Grippin, Jeffrey S Weinberg, Shaan M Raza, Franco Demonte, Ian E Mccutcheon, Sujit Prabhu, Sherise D Ferguson, Chibawanye I Ene, Kadir Akdemir, Sreyashi Basu, Sonali Jindal, Benjamin R Schrank, Jian Hu, Sangeeta Goswami, Vinay K Puduvalli, Frederick F Lang, Kristin Huntoon, Padmanee Sharma, Betty Y S Kim, Wen Jiang

Faculty, Staff and Student Publications

Macrophage-mediated phagocytosis of tumor cells elicits potent antitumor immunity. Nonetheless, sole-blockade of the anti-phagocytosis molecule CD47 has yielded insufficient therapeutic outcomes. Here, we report that glioblastoma (GBM) cells expressed abundant levels of phagocytosis checkpoint CD24. We further show that dual blockade of CD24 and CD47 synergistically enhances the pro-phagocytic activity of macrophages, thereby improving tumor antigen cross-presentation and activating the cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway. This innate immune activation facilitates T cell infiltration into tumors and sensitizes tumors to anti-PD1 therapy, improving survival outcomes in murine GBM models, including immunosuppressive tumors reflecting human GBM-like features. Thus, our …

Microrna-625-3p Increases Chemosensitivity In Ovarian Cancer Cells Through Decreasing Ssx2ip-Mediated Cisplatin Export In Extracellular Vesicles, Chi-Lam Au-Yeung, Tetsushi Tsuruga, Marina A Talor, Yadira J Pacheco, Guangan He, Zahid H Siddik, Byeong J Cha, Suet-Ying Kwan, Kwong-Kwok Wong, Kay-Pong Yip, Samuel C Mok

Faculty, Staff and Student Publications

Introduction: Advanced-stage high-grade serous ovarian cancer (HGSC) is a disease that is difficult to manage due to its heterogeneous clinical behavior. No reliable prediction of response to chemotherapy is currently available and the overall survival rate remains poor. Herein, we sought to determine the molecular mechanisms by which microRNAs (miRNAs) confer chemoresistance in ovarian cancer and demonstrate the efficacy of targeting miRNAs to sensitize HGSC to cisplatin treatment.

Methods: Next-generation miRNA sequencing was performed using microdissected HGSC specimens to identify an miRNA signature for intrinsic chemoresistance, and miR-625-3p was selected for further study. The effects of miR-625-3p on cisplatin sensitivity …

Bi-Allelic Variants In Nrdc Cause A Neurodevelopmental Disorder Characterized By Neonatal Lethality, Microcephaly, And Brain Abnormalities, Davut Pehlivan, Abigail Sandoval, Reza Maroofian, François Lecoquierre, Aisha M Al Shamsi, Gyu S Lee, Osman Yesilbas, Preston Taylor, Matthew B Mcdougal, Vahid Bahrambeigi, Omid Aryani, Juan Felipe Ramirez, Khalid Hama Salih, Chadi Al Alam, Heba Morsy, Haytham Hussien, Tarek Omar, Ibrahim M Abdelrazek, Anne Claire Brehin, Dana Marafi, Tugba Kalayci, Jubran Abu Rahma, Jawabreh Kassem Talbeya, Husein Dabbah, Eric Verspyck, Toktam Moosavian, Jawid M Fatih, Tadahiro Mitani, Gulsen Akay, Daniel G Calame, Anne-Marie Guerrot, Wendy K Chung, Henry Houlden, James R Lupski, Adel Shalata, Wan Hee Yoon

Faculty, Staff and Students Publications

Nardilysin (NRDC) plays a role in multiple cellular functions in diverse cellular compartments, including ectodomain shedding in the plasma membrane, as well as chaperoning a key Krebs cycle enzyme in mitochondria. We had previously reported limited clinical information from two individuals with homozygous frameshift variants in NRDC. With inclusion of previously published individuals, here we report 14 individuals (10 females, four males) from nine unrelated families carrying homozygous NRDC pathogenic variants. Common clinical features include severe to profound developmental delay/intellectual disability (12/12), microcephaly (13/13), prematurity (5/13), lethality in the first 3 years of life (9/14), seizures (7/11), joint contractures (4/8), …

Modulating Alternative Splicing Of Mecp2 Is A Potential Therapeutic Strategy For Rett Syndrome, Harini P Tirumala, Li Wang, Yan Li, Sameer S Bajikar, Ashley G Anderson, Wei Wang, Alexander J Trostle, Mahla Zahabiyon, Aleksandar Bajic, Jean J Kim, Hu Chen, Zhandong Liu, Huda Y Zoghbi

Faculty, Staff and Students Publications

Rett syndrome (RTT) is a neurological disorder caused by loss-of-function mutations in methyl CpG binding protein 2 (MECP2), a transcriptional regulator essential for maintenance of normal neuronal function. The current FDA-approved treatment for RTT, Trofinetide, mildly alleviates some symptoms. In contrast, re-introducing MeCP2 or increasing its amount through transgenesis in mouse RTT models improves most neurological phenotypes and enhances survival. Here, we devised a therapeutic strategy to moderately increase MeCP2 protein by modulating the alternative splicing of MECP2 to switch the less efficiently translated e2 to the more efficiently translated e1 isoform. We deleted Mecp2 exon 2 (unique …

Circulating Ketone Bodies And Incident Cardiovascular Outcomes And Mortality: Insights From The Uk Biobank, Parag Anilkumar Chevli, Saeid Mirzai, Richard Kazibwe, Jeff Kingsley, Alexis C Wood, Joseph Yeboah, Leandro Slipczuk, Anurag Mehta, Harpreet S Bhatia, Ambarish Pandey, Michael D Shapiro

Children’s Nutrition Research Center Staff Publications

Background: Ketone bodies (KB) are endogenous energy sources synthesized by the liver in response to metabolic stress. Their associations with atherosclerotic cardiovascular disease (ASCVD), heart failure (HF), and mortality and their potential beneficial or harmful effects have yet to be determined. This study aimed to examine the association between KB and incident cardiovascular outcomes and mortality in a large general population cohort free from ASCVD and HF at baseline.

Methods: This analysis included 90 987 participants (mean age 56.4 ± 8.1 years; 54.7% women) from the UK Biobank without prevalent ASCVD or HF. KB were measured by nuclear magnetic resonance …

Ectopic B Lymphocyte Follicles Exacerbate Ischemic Brain Damage Via Mif-Cd74/Cxcr4 And Interferon Signaling, Sheng Yang, Hang Zhang, Lu-Lu Xu, Luo-Qi Zhou, Yun-Hui Chu, Lian Chen, Xiao-Wei Pang, Lu-Yang Zhang, Li-Fang Zhu, Ming-Hao Dong, Ke Shang, Jun Xiao, Long-Jun Wu, Wei Wang, Dai-Shi Tian, Chuan Qin

Faculty, Staff and Student Publications

Neuroinflammation, encompassing both innate and adaptive immune responses, plays a crucial role in ischemic stroke. Although B lymphocytes are central to adaptive immunity, their contributions to ischemic stroke remain poorly understood. Here, we demonstrated that B lymphocytes accumulate in ischemic lesions, forming germinal center-like structures at the later stage after stroke, which mainly depended on in situ proliferation. This accumulation correlated with worsened neuroinflammation and ischemic injury, whereas B cell depletion reduced chronic brain damage during stroke. Mechanistically, microglia recruited B cells into ischemic lesions through MIF-CD74/CXCR4 signaling during the early phase of stroke, while IFN-related pathways in B cells …

Intouch Week Of March 2, 2026, New York Medical College

InTouch

• Kartik Prabhakaran, M.D., to Lead Department of Surgery
• Uncovering an Early Driver of Pulmonary Arterial Hypertension
• What if Banana Bags Came Ready to Use?
• NYMC and TU Host "Ninety Minutes: The Medical Magazine of the Web"
• Pet the Stress Away Brings Comfort to NYMC 
• Free Shipping on NYMC Gear
• Student Spotlight: Building an Orthopedic Future

Poly(Adp-Ribose) Glycohydrolase Enforces P21 Degradation Via Deparylation To Promote Gastric Cancer Progression, Yangchan Hu, Qimei Bao, Yixing Huang, Yan Wang, Xin Zhao, Junjun Nan, Yuxin Meng, Mingcong Deng, Yuancong Li, Zirui Zhuang, Hanyi He, Dan Zu, Yuke Zhong, Chunkai Zhang, Bing Wang, Ran Li, Yanhua He, Qihan Wang, Min Liu, John A Tainer, Yin Shi, Xiangdong Cheng, Ji Jing, Zu Ye

Faculty, Staff and Student Publications

Dysregulation of cell cycle checkpoints is a cancer hallmark, with ubiquitination-controlled protein stability playing a pivotal role. Although p21, a key cyclin-dependent kinase inhibitor, is tightly regulated by ubiquitin-mediated degradation, the key upstream modulators of its ubiquitination remain incompletely defined. Here, we identify poly(ADP-ribose) glycohydrolase (PARG) as a regulator of p21 stability in gastric cancer (GC) cells. We show that PARG expression is markedly upregulated in GC tissues and correlates with poor patient prognosis. Functional assays revealed that genetic depletion of PARG triggers G2/M phase arrest and impairs GC cell proliferation. Mechanistically, we demonstrate that PARG loss enhances p21 PARylation, …

Mechanometabolism Instructs Hematopoietic Stem Cell Specification, Paulina D Horton, Alina Syed, Michelle Winkler, Abishek B Vaidya, Michael Rariden, Neha Arora, Yong Zhou, Michihiro Kobayashi, Momoko Yoshimoto, Hyun Jung Lee, Hyun-Eui Kim, John P Hagan, Catherine Denicourt, Travis I Moore, Pamela L Wenzel

Faculty, Staff and Student Publications

Mechanical force generated by blood flow stimulates emergence of the first hematopoietic stem cells (HSCs) that populate the blood system. Force drives the transition of HSC precursors from an endothelial to hematopoietic identity, yet the molecular regulation of this fate switch remains poorly understood. We report that shear stress triggers adaptation in mitochondrial composition, ultrastructure, and function, which are essential for hematopoietic fate and engraftment potential. Shear stress remodels mitochondria in hemogenic endothelium by promoting mitochondrial gene transcription and protein synthesis. Laminar flow selectively initiates translation of 5' terminal polypyrimidine (5'TOP) motif-containing transcripts, which commonly encode ribosome and translation machinery. …

Activin A Secretion By Muscle-Repairing Macrophages Induces Heterotopic Ossification In Mice, Wenqiang Yin, Kazuo Okamoto, Asuka Terashima, Warunee Pluemsakunthai, Takehito Ono, Taku Ito-Kureha, Shizuo Akira, Yoshinobu Hashizume, Roland Baron, Satoshi Ueha, Kouji Matsushima, Martin M Matzuk, Yuji Mishina, Hiroshi Takayanagi

Faculty, Staff and Students Publications

The immune system is not only essential for host defense, but it is also involved in tissue maintenance and disease pathogenesis. Macrophages play a key role in tissue repair, fibrosis, and tumorigenesis, but the mechanisms underlying their multifunctionality have not been fully explored. Here, we identified Mrep (Ly6ChiCX3CR1loPDPN+CD9+) as a crucial subset of macrophages for muscle regeneration after muscle injury. Muscle regeneration required Mrep-derived activin A, which was produced via the TLR4/TIR domain-containing adapter-inducing interferon-β/TANK-binding kinase 1/interferon regulatory factor 3/7 signaling pathway in response to muscle injury. Mrep exerted pathological effects by secreting activin A in a model of genetically …

The Impact Of Human Myoblasts On Macrophage Polarization In A Coculture Model, Elisabeth Ann Stodola

Biomedical Engineering

Peripheral Artery Disease (PAD) is characterized by the buildup of atherosclerotic plaque in the lower extremities that occludes blood flow, and affects over 200 million people worldwide. Without effective treatment, PAD can lead to claudication, ischemia, ulcers, and gangrene. PAD causes more amputations in the United States than any other condition, and for severe cases that require revascularization, procedures benefit fewer than 50% of patients. This demonstrates a clear need for alternative therapies. Potential therapies for PAD target expansion of collateral blood vessels around the area of occlusion – a process called arteriogenesis to compensate for loss of blood flow …

Physical And Occupational Therapist Evaluations For Fall Prevention In The Emergency Department: A Geriatric Ed Guidelines 2.0 Systematic Review, Lauren T Southerland, Pedro K Curiati, Richard D Shih, Alexander X Lo, Kristie Harper, Ian Tarnovsky, Alexis Brengartner, Luna Ragsdale, Neha Raukar, Suzanne Ryer, Katherine M Hunold, Fabrice Mowbray, Charles L Maddow, Christopher R Carpenter, Shan W Liu

Faculty, Staff and Student Publications

Background: Older adults are at high risk for severe injuries and death from falls. Physical therapist (PT) and occupational therapist (OT) evaluations have been introduced into Emergency Department (ED) care to assist with fall risk evaluation and fall prevention care. An evaluation of current evidence was undertaken to inform the Geriatric ED Guidelines 2.0.

Methods: Systematic review of physical and/or occupational therapy evaluation for fall prevention in the ED. The intervention was evaluation by a rehabilitation therapist (PT, OT, or both) for fall prevention, fall assessment, or mitigation of fall risk factors. Studies that did not perform the evaluation during …

The Role Of Top-Down Appetite Self-Regulation In The Development Of Healthy Eating Behaviors Among Children: A Narrative Review And Socialization Framework, David J Bridgett, Sheryl O Hughes, Matthew Broussard, Daniela Mccourt, Christina M Croce, Jennifer O Fisher

Children’s Nutrition Research Center Staff Publications

Appetite self-regulation (ASR) among children is thought to have a fundamental role in shaping the development of healthy eating behaviors, dietary intake, and growth during childhood. Parallel to developmental frameworks for understanding "general" self-regulation among children, ASR has been described as involving children's use of "top-down" cognitive processes to moderate "bottom-up" biological drives around food approach and avoidance in the interest of achieving desired eating behaviors or outcomes. Whereas bottom-up ASR processes during early childhood are well characterized, particularly in the context of dysregulation and obesity risk, the role of top-down ASR processes in the development of healthy eating behaviors …

Pre- And Postnatal Exposure To Pm2.5 And No2 And Blood Pressure In Children: Results From The Echo Cohort, Yu Ni, Andrew Law, Xingyu Gao, Adam A Szpiro, Christine T Loftus, Miranda Jones, Logan C Dearborn, Marnie F Hazlehurst, Allison R Sherris, Sindana Ilango, Kaja Z Lewinn, Nicole R Bush, Qi Zhao, Leonardo Trasande, Joseph T Flynn, Daniel A Enquobahrie, Ruby H N Nguyen, Tom O'Connor, Arpita K Vyas, Mingyu Zhang, Hooman Mirzakhani, Alison Hipwell, Anne Starling, Alicia K Peterson, Akhgar Ghassabian, Assiamira Ferrara, Judy Aschner, Scott Collingwood, Margaret R Karagas, Michelle Katzow, Annemarie Stroustrup, Mehtap Haktnair, Tina V Hartert, Brittney M Snyder, Sophia Jan, Anne Marie Singh, Dana Dabelea, Angela M Malek, Jennifer K Straughen, Carlos A Camargo, Miatta A Buxton, Rosalind Wright, Kecia Carroll, Keia Sanderson, Daphne Koinis Mitchell, Viren D'Sa, Christine Hockett, Anne L Dunlop, Shohreh F Farzen, Sunni L Mumford, Akram N Alshawabkeh, Hudson P Santos, Xueying Zhang, Zhongzheng Niu, Nan Ji, Carrie Breton, Donghai Liang, Catherine J Karr, Echo Cohort Consortium

Children’s Nutrition Research Center Staff Publications

Background: There is growing interest in understanding the link between early life exposures to ambient air pollution and childhood blood pressure; however, existing findings, largely from single site/cohort studies, are inconclusive.

Methods: We examined the association between exposures to fine particulate matter (PM2.5) and nitrogen dioxide (NO2) and blood pressure measured at age 5-12 years in 4863 U.S. children from 20 pregnancy cohorts of the NIH ECHO cohort. Point-based residential exposures were derived from spatiotemporal models with a biweekly resolution and averaged over each trimester, the whole pregnancy, and child age 0-2 years. We converted systolic (SBP) and diastolic blood …

Diversity And Immune Dynamics Of Choroid Plexus Macrophages Are Shaped By Distinct Developmental Origins, Siling Du, Khai M Nguyen, Alina Ulezko Antonova, Jose L Fachi, Patrick Fernandes Rodrigues, Alice Verdiani, Martina Molgora, Igor Smirnov, Jasmin Herz, Tornike Mamuladze, Jennifer Ponce, Amanda Swain, Mattia Bugatti, Susan Gilfillan, Marina Cella, William Vermi, Jonathan Kipnis, Marco Colonna, Simone Brioschi

The Brown Foundation: Institute of Molecular Medicine

The choroid plexus forms a key barrier and signaling interface between the brain and peripheral circulation, yet its immune landscape remains incompletely understood. Using single-cell transcriptomics combined with lineage and spatial tracing methods, we identified three biologically distinct populations of choroid plexus macrophages, defined by differential expression of CD163, MHCII or CD9. These subsets arise from separate hematopoietic waves, occupy distinct anatomical niches and differentially rely on CSF1 and IL-34 for survival. We found that TGFβ signaling is essential to maintain their tissue-specific identities, and deletion of Tgfbr2 in these cells induces broad phenotypic reprogramming. During neuroinflammation, choroid plexus macrophages …

Glutamatergic Dysfunction Of Astrocytes In Paraventricular Nucleus Of Thalamus Contributes To Adult Anxiety Susceptibility In Adolescent Ethanol Exposed Mice, Aubrey Bennett, Hyunjung Kim, David Thomas, Peter Biggs, Roxan Ara, Asamoah Bosomtwi, Seungwoo Kang

The Brown Foundation: Institute of Molecular Medicine

Repeated ethanol exposure during adolescence increases adult anxiety risk, but the underlying mechanisms remain unclear. The paraventricular nucleus of the thalamus (PVT) has been considered a hub for controlling anxiety and is affected by experiences from early life. Thus, this study investigated how adolescent intermittent repeated ethanol exposure (AIE) affects the PVT activities and anxiety-related behaviors in adulthood. We found that AIE triggers anxiety-like behaviors and parallelly exhibited elevated firing rates and increased calcium signaling in the PVT neurons compared to control counterpart mice. Chemogenetic inhibition of PVT neurons reduced anxiety-like behaviors in AIE-treated animals, confirming PVT's role in adolescent …

Lipids Grease The Chain Of Cancer Progression, Joseph Rupert, Pham Hong Anh Cao, Daniel E Frigo, Mikhail G Kolonin

The Brown Foundation: Institute of Molecular Medicine

The role of lipids in cancer progression has become a fervent area of exploration. The crosstalk of tumors with adipose tissue is a complex but well-regulated orchestration of signaling pathways, lipid transporters, and enzymes. They regulate fatty acid synthesis, their deposition into lipid droplets (LDs) as triglycerides, induction of lipolysis, shuttling lipids across cells, and their systemic trafficking, modification, and catabolism. For the latter, lipid oxidation has emerged as a metabolic process of particular clinical importance. Products of lipid processing can become secondary messengers, contribute to reactive oxygen species (ROS) generation, stimulate the production of antioxidants, and, if left unchecked, …

Pharmacokinetic Modeling Strategies For Dynamic Hyperpolarized Urea Imaging, Keith A Michel, Collin J Harlan, Christopher M Walker, Matthew E Merritt, Yunyun Chen, Stephen Y Lai, James A Bankson

Faculty, Staff and Student Publications

Purpose: To evaluate pharmacokinetic modeling methods for quantification of tissue perfusion/permeability with hyperpolarized 13C urea.

Methods: Three models for quantitative analysis of dynamic HP urea imaging data were proposed and evaluated in numerical simulations and a thyroid cancer mouse model. A multicompartment model resembling the extended Tofts model for DCE-MRI (Model I) and two simplified models were used. The simplified models each eliminate a volume parameter representing vascular (Model II) or impermeable cellular space (Model III). Signal curves were generated from Model I, and models were fit to these synthetic data to quantify the effects of acquisition settings, bias in …

A Patient-Derived Organ-On-Chip Platform For Modeling The Tumor Microenvironment And Drug Responses In Pancreatic Cancer, Darbaz Adnan, Natan Roberto De Barros, Luca S Santovito, Xuhong Cheng, Kristi M Lawrence, Mariah K Barnett, Martine D Boetto, Neal Mehta, Ajaypal Singh, Lin Cheng, Xiangsheng Huang, Faraz Bishehsari

Faculty, Staff and Student Publications

Pancreatic ductal adenocarcinoma (PDAC) is a fatal malignancy. Current conventional chemotherapeutics are inadequate in controlling the disease; hence, there is an urgent need for precision medicine. Ex vivo models that replicate the tumor and its microenvironment can advance precision medicine in PDAC. Patient‐derived organoids (PDOs) offer a promising solution by retaining the functional features of the tumor, allowing for individualized study of cancer biology and drug response. However, PDOs fall short in replicating the tumor microenvironment (TME), which includes various stromal and immune cells influencing tumor growth and chemoresistance. We hypothesize that combining PDO technology with organ‐on‐a‐chip (OoC) systems can …

Shiga Toxin Increases Intestinal Transit To Displace Resident Microbes And Facilitate Pathogen Colonization, Max A Odem, Sabona B Simbassa, Cecilia Fadhel Alvarez, Oliyad Jeilu, Shelby R Simar, Rachel Bosserman, Soumita Dutta, Walter Galdamez, Hossaena Ayele, Blake M Hanson, Diana M Proctor, Anne Marie Krachler

Faculty, Staff and Student Publications

Shiga toxin (Stx)-producing Escherichia coli (STEC) is a major cause of food-borne illnesses, and disease severity correlates with the production of Shiga toxins. While clinical symptoms such as bloody diarrhea and hemolytic uremic syndrome have been attributed to Stx, its contribution to bacterial fitness is not well understood. Here, we demonstrate that Stx2 enhances STEC colonization of the zebrafish gut by facilitating the partial displacement of gut resident microbes. Infection with Stx2-producing STEC strains or direct exposure of fish to purified Stx2 induces alterations in the zebrafish microbiome structure, impacting several bacterial phyla and genera, notably Pseudomonads. We show that …

Alpha 7 Nicotinic Acetylcholine Receptor Contributes To Long-Term Cognitive Recovery Following Ischemic Stroke, Dustin T Nguyen, Kate Mendoza, Cassandra Hall, Chunfeng Tan, Anjali Chauhan

Faculty, Staff and Student Publications

Stroke is associated with autonomic dysfunction and reduced acetylcholine (ACh), a neurotransmitter critical for cognition. ACh signals in part through the alpha-7 nicotinic acetylcholine receptor (α7nAChR), a ligand-gated ion channel involved in synaptic plasticity, learning, and memory. Impaired α7nAChR signaling has been linked to heightened neuroinflammation and poor acute stroke recovery. Here, we investigated whether α7nAChR contributes to post-stroke cognitive recovery in young male mice. Wild-type (WT) and α7nAChR knockout (α7n0KO) mice underwent 60-min middle cerebral artery occlusion (MCAO). In a pharmacology cohort, the α7nAChR agonist GTS-21 was administered immediately after reperfusion and then daily for 20 days. Cognitive performance …

Clemastine Ameliorates Cognitive Deficits In An Experimental Rat Model Of Chronic Cerebral Hypoperfusion, Xuemei Zong, Zhihai Huang, Fanfei Kong, Yu Feng, Yulan Zhang, Peibin Zou, Hung Wen Lin, David C Hess, Quanguang Zhang

Faculty, Staff and Student Publications

Chronic cerebral hypoperfusion (CCH) profoundly affects patient well-being and has been proposed as a risk factor for cognitive impairment and dementia. However, due to the limited understanding of the pathophysiology of CCH, there are currently no effective preventive or therapeutic approaches for CCH-associated cognitive impairment. Therefore, identifying new targets for CCH is essential to bridge this knowledge gap. In this study, we sought to determine whether enhanced myelination could prevent cognitive impairment associated with CCH. Experimental CCH was induced via bilateral common carotid artery occlusion (BCCAO) in rats, and clemastine, a well-established pro-myelinating agent, was administered to boost myelin renewal. …

Beyond Short Microhomologies: Mismatch-Compatible Pol Θ-Mediated Dna Damage Repair, Yuzhen Li, Richard D Wood

Faculty, Staff and Student Publications

DNA polymerase θ (Pol θ)-mediated end-joining (TMEJ), one of several pathways for repairing DNA double-strand breaks, is traditionally thought to initiate via anchoring at short, consecutive, and perfectly matched microhomologies (MHs). Emerging evidence indicates that Pol θ can utilize MHs containing mismatches both in vitro and in vivo. This revised definition of MH provides a mechanistic explanation for a broader spectrum of Pol θ-dependent repair outcomes. Here, we summarize recent findings on the revised definition of MHs utilized by Pol θ, assess the applicability of this concept across species, and compare TMEJ with other (micro)hom(e)ology-mediated repair pathways. We explore how …