Biochemistry, Biophysics, and Structural Biology Commons^™

A Mouse Holder For Awake Functional Imaging In Unanesthetized Mice: Applications In 31p Spectroscopy, Manganese-Enhanced Magnetic Resonance Imaging Studies, And Resting-State Functional Magnetic Resonance Imaging, Lindsay C Fadel, Ivany V Patel, Jonathan Romero, I-Chih Tan, Shelli R Kesler, Vikram Rao, S A Amali S Subasinghe, Russell S Ray, Jason T Yustein, Matthew J Allen, Brian W Gibson, Justin J Verlinden, Stanley Fayn, Nicole Ruggiero, Caitlyn Ortiz, Elizabeth Hipskind, Aaron Feng, Chijindu Iheanacho, Alex Wang, Robia G Pautler

Faculty, Staff and Students Publications

Anesthesia is often used in preclinical imaging studies that incorporate mouse or rat models. However, multiple reports indicate that anesthesia has significant physiological impacts. Thus, there has been great interest in performing imaging studies in awake, unanesthetized animals to obtain accurate results without the confounding physiological effects of anesthesia. Here, we describe a newly designed mouse holder that is interfaceable with existing MRI systems and enables awake in vivo mouse imaging. This holder significantly reduces head movement of the awake animal compared to previously designed holders and allows for the acquisition of improved anatomical images. In addition to applications in …

Association Between Social Vulnerability Index And Cardiovascular Disease: A Behavioral Risk Factor Surveillance System Study, Vardhmaan Jain, Mahmoud Al Rifai, Safi U Khan, Ankur Kalra, Fatima Rodriguez, Zainab Samad, Yashashwi Pokharel, Arunima Misra, Laurence S Sperling, Jamal S Rana, Waqas Ullah, Ankit Medhekar, Salim S Virani

Faculty, Staff and Students Publications

Background Social and environmental factors play an important role in the rising health care burden of cardiovascular disease. The Centers for Disease Control and Prevention developed the Social Vulnerability Index (SVI) from US census data as a tool for public health officials to identify communities in need of support in the setting of a hazardous event. SVI (ranging from a least vulnerable score of 0 to a most vulnerable score of 1) ranks communities on 15 social factors including unemployment, minoritized groups status, and disability, and groups them under 4 broad themes: socioeconomic status, housing and transportation, minoritized groups, and …

Dual Mechanisms Implemented By Lin-28 For Positive Regulation Of Hbl-1 Are Necessary For Proper Development Of Distinct Tissues In Caenorhabditis Elegans, Madeleine Minutillo

Graduate School of Biomedical Sciences Theses and Dissertations

In Caenorhabditis elegans, the heterochronic pathway is comprised of a hierarchy of genes that control the proper timing of developmental events. hbl-1 (Hunchback Like-1) encodes an Ikaros family zinc-finger transcription factor that promotes the L2 stage cell fate events of the hypodermis. The downregulation ofhbl-1 is a crucial step for the transition from the L2 to the L3 stage. There are two known processes through which negative regulation of hbl-1 occurs: suppression of hbl-1 expression by 3 let-7 miRNAs through the hbl-1 3’UTR and inhibition of HBL-1 activity by LIN-46. The mechanisms by which hbl-1 is positively regulated have not …

Identifying A Glucocorticoid-Activated Gpcr That Rapidly And Non-Genomically Increases Camp Levels In Mammalian Cells, Francisco Nunez

Pharmaceutical Sciences (PhD) Dissertations

Glucocorticoids (GCs) are steroid hormones that regulate diverse physiological processes. Synthetic versions of GCs are commonly used to treat inflammatory diseases such as asthma by modulating gene expression to suppressing several inflammatory activities. However, it is estimated that 5-10% of asthmatics are unresponsive to GCs, which may be explained by receptor desensitization and/or the presence of a neutrophilic endotype. One understudied phenomenon of GCs is their ability to induce rapid, non-genomic actions. For example, GCs can acutely modulate calcium concentrations levels, induce smooth muscle relaxation and modulate nitric oxide synthase activity, within minutes and sometimes seconds, which is too rapid …

Randomized Placebo-Controlled Trial Of Losartan For Pediatric Nafld, Miriam B Vos, Mark L Van Natta, Niviann M Blondet, Srinivasan Dasarathy, Mark Fishbein, Paula Hertel, Ajay K Jain, Saul J Karpen, Joel E Lavine, Saeed Mohammad, Laura A Miriel, Jean P Molleston, Marialena Mouzaki, Arun Sanyal, Emily P Sharkey, Jeffrey B Schwimmer, James Tonascia, Laura A Wilson, Stavra A Xanthakos, Nash Clinical Research Network

Faculty, Staff and Students Publications

BACKGROUND AND AIMS: To date, no pharmacotherapy exists for pediatric NAFLD. Losartan, an angiotensin II receptor blocker, has been proposed as a treatment due to its antifibrotic effects.

APPROACH AND RESULTS: The Nonalcoholic Steatohepatitis Clinical Research Network conducted a multicenter, double-masked, placebo-controlled, randomized clinical trial in children with histologically confirmed NAFLD at 10 sites (September 2018 to April 2020). Inclusion criteria were age 8-17 years, histologic NAFLD activity score ≥ 3, and serum alanine aminotransferase (ALT) ≥ 50 U/l. Children received 100 mg of losartan or placebo orally once daily for 24 weeks. The primary outcome was change in ALT …

Integrated Multi-Omic Characterization Of Congenital Heart Disease, Matthew C Hill, Zachary A Kadow, Hali Long, Yuka Morikawa, Thomas J Martin, Emma J Birks, Kenneth S Campbell, Jeanne Nerbonne, Kory Lavine, Lalita Wadhwa, Jun Wang, Diwakar Turaga, Iki Adachi, James F Martin

Faculty, Staff and Students Publications

The heart, the first organ to develop in the embryo, undergoes complex morphogenesis that when defective results in congenital heart disease (CHD). With current therapies, more than 90% of patients with CHD survive into adulthood, but many suffer premature death from heart failure and non-cardiac causes1. Here, to gain insight into this disease progression, we performed single-nucleus RNA sequencing on 157,273 nuclei from control hearts and hearts from patients with CHD, including those with hypoplastic left heart syndrome (HLHS) and tetralogy of Fallot, two common forms of cyanotic CHD lesions, as well as dilated and hypertrophic cardiomyopathies. We …

The Role Of The Hypoxia-Inducible Factor 2 In Pancreatic Cancer: Mechanisms Of Tumor Immunosuppression And Intestinal Radioprotection, Carolina Garcia Garcia

Dissertations and Theses (Open Access)

Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease with dismal prognosis. The only curative option for patients is surgery, but over 80% of patients are not surgical candidates. Unfortunately, PDAC is resistant to the three remaining options. PDAC is characterized by a profoundly hypoxic and immunosuppressive stroma, which contributes to its therapeutic recalcitrance. Alpha-smooth muscle actin+ (αSMA+) cancer-associated fibroblasts (CAFs) are the most abundant stromal component, as well as mediators of stromal deposition. The hypoxia-inducible factors (HIF1 and HIF2) coordinate responses to hypoxia, yet, despite their known association to poor patient outcomes, their functions within the PDAC tumor microenvironment (TME) …

Sex-Specific Phenotypes In The Aging Mouse Heart And Consequences For Chronic Fibrosis, Aude Angelini, Jesus Ortiz-Urbina, Joann Trial, Anilkumar K Reddy, Anna Malovannaya, Antrix Jain, Mark L Entman, George E Taffet, Katarzyna A Cieslik

Faculty, Staff and Students Publications

The incidence of diastolic dysfunction increases with age in both humans and mice. This is characterized by increased passive stiffness and slower relaxation of the left ventricle. The stiffness arises at least partially from progressively increased interstitial collagen deposition because of highly secretory fibroblasts. In the past, we demonstrated that AMPK activation via the drug 5-aminoimidazole-4-carboxamide riboside (AICAR) in middle-aged mice reduced adverse remodeling after myocardial infarction. Therefore, as an attempt to normalize the fibroblast phenotype, we used 21-mo-old male and female mice and treated them with AICAR (0.166 mg/g body wt) where each mouse was followed in a functional …

Maladaptive Positive Feedback Production Of Chrebpβ Underlies Glucotoxic Β-Cell Failure, Liora S Katz, Gabriel Brill, Pili Zhang, Anil Kumar, Sharon Baumel-Alterzon, Lee B Honig, Nicolás Gómez-Banoy, Esra Karakose, Marius Tanase, Ludivine Doridot, Alexandra Alvarsson, Bennett Davenport, Peng Wang, Luca Lambertini, Sarah A Stanley, Dirk Homann, Andrew F Stewart, James C Lo, Mark A Herman, Adolfo Garcia-Ocaña, Donald K Scott

Faculty, Staff and Students Publications

Preservation and expansion of β-cell mass is a therapeutic goal for diabetes. Here we show that the hyperactive isoform of carbohydrate response-element binding protein (ChREBPβ) is a nuclear effector of hyperglycemic stress occurring in β-cells in response to prolonged glucose exposure, high-fat diet, and diabetes. We show that transient positive feedback induction of ChREBPβ is necessary for adaptive β-cell expansion in response to metabolic challenges. Conversely, chronic excessive β-cell-specific overexpression of ChREBPβ results in loss of β-cell identity, apoptosis, loss of β-cell mass, and diabetes. Furthermore, β-cell "glucolipotoxicity" can be prevented by deletion of ChREBPβ. Moreover, ChREBPβ-mediated cell death is …

Heart Failure In General And Cardiac Transplant Patients With Covid-19, Munish Sharma, Gowthami Sai Kogilathota Jagirdhar, Kalpalatha K Guntupalli, Rahul Kashyap, Salim Surani

Faculty, Staff and Students Publications

Coronavirus disease 2019 (COVID-19) is primarily an infection of the respiratory tract, but it can have multisystem manifestations. Cardiac complications of COVID-19 can range from acute myocardial injury, cardiac arrhythmias, or heart failure, amongst others. Heart failure (HF) in COVID-19 can be a de novo process or due to worsening of pre-existing cardiovascular ailment. HF in a patient with COVID-19 not only poses challenges in clinical presentation and management of COVID-19 but also affect prognosis of the patient. This article aims to succinctly revisit the implications of this pandemic regarding pre-existing HF or new-onset HF based on prevailing data. It …

Effect Of High- Vs Low-Dose Tranexamic Acid Infusion On Need For Red Blood Cell Transfusion And Adverse Events In Patients Undergoing Cardiac Surgery: The Optimal Randomized Clinical Trial, Jia Shi, Chenghui Zhou, Wei Pan, Hansong Sun, Sheng Liu, Wei Feng, Weijian Wang, Zhaoyun Cheng, Yang Wang, Zhe Zheng, Optimal Study Group

Faculty, Staff and Students Publications

IMPORTANCE: Tranexamic acid is recommended for reducing blood loss and transfusion in cardiac surgery. However, it remains unknown whether a high dose of tranexamic acid provides better blood-sparing effect than a low dose without increasing the risk of thrombotic complications or seizures in cardiac surgery.

OBJECTIVE: To compare the efficacy and adverse events of high-dose vs low-dose tranexamic acid in patients undergoing cardiac surgery with cardiopulmonary bypass.

DESIGN, SETTING, AND PARTICIPANTS: Multicenter, double-blind, randomized clinical trial among adult patients undergoing cardiac surgery with cardiopulmonary bypass. The study enrolled 3079 patients at 4 hospitals in China from December 26, 2018, to …

Persistent Ethnicity-Associated Disparity In Anti-Tumor Effectiveness Of Immune Checkpoint Inhibitors Despite Equal Access, Marcus A Florez, Jan O Kemnade, Nan Chen, Wendy Du, Anita L Sabichi, Daniel Y Wang, Quillan Huang, Courtney N Miller-Chism, Aparna Jotwani, Albert C Chen, David Hernandez, Vlad C Sandulache

Faculty, Staff and Students Publications

We reviewed response to immune checkpoint inhibitors (ICI) of 207 patients with diagnoses of lung or head and neck cancer treated with chemotherapy/ICI combination therapy and ICI monotherapy between 2015 and 2020 at one of three clinical pavilions associated with the Dan L. Duncan Comprehensive Cancer Center at Baylor College of Medicine. Two of these pavilions (Harris Health System and the Michael E. DeBakey Veterans Affairs Medical Center) serve large minority populations and provide equal access to care regardless of means. 174 patients had a diagnosis of lung cancer (non-small cell or small cell) and 33 had a diagnosis of …

A Narrative Review On Yoga: A Potential Intervention For Augmenting Immunomodulation And Mental Health In Covid-19, Indranill Basu-Ray, Kashinath Metri, Dibbendhu Khanra, Rishab Revankar, Kavitha M Chinnaiyan, Nagaratna Raghuram, Mahesh Chandra Mishra, Bhushan Patwardhan, Manjunath Sharma, Ishwar V Basavaraddi, Akshay Anand, Shrinath Reddy, K K Deepak, Marian Levy, Sue Theus, Glenn N Levine, Holger Cramer, Gregory L Fricchione, Nagendra R Hongasandra

Faculty, Staff and Students Publications

BACKGROUND: The ongoing novel coronavirus disease 2019 (COVID-19) pandemic has a significant mortality rate of 3-5%. The principal causes of multiorgan failure and death are cytokine release syndrome and immune dysfunction. Stress, anxiety, and depression has been aggravated by the pandemic and its resultant restrictions in day-to-day life which may contribute to immune dysregulation. Thus, immunity strengthening and the prevention of cytokine release syndrome are important for preventing and minimizing mortality in COVID-19 patients. However, despite a few specific remedies that now exist for the SARS-CoV-2virus, the principal modes of prevention include vaccination, masking, and holistic healing methods, such as …

Extracellular Domain Of Pept1 Interacts With Tm1 To Facilitate Substrate Transport, Jiemin Shen, Miaohui Hu, Xiao Fan, Zhenning Ren, Corinne Portioli, Xiuwen Yan, Mingqiang Rong, Ming Zhou

Faculty, Staff and Students Publications

Mammalian peptide transporters, PepT1 and PepT2, mediate uptake of small peptides and are essential for their absorption. PepT also mediates absorption of many drugs and prodrugs to enhance their bioavailability. PepT has twelve transmembrane (TM) helices that fold into an N-terminal domain (NTD, TM1–6) and a C-terminal domain (CTD, TM7–12), and has a large extracellular domain (ECD) between TM9–10. It is well-recognized that peptide transport requires movements of the NTD and CTD, but the role of the ECD in PepT1 remains unclear. Here we report the structure of horse PepT1 encircled in lipid nanodiscs and captured in the inward-open apo …

Structure-Activity Relationship And Antitumor Activity Of 1,4-Pyrazine-Containing Inhibitors Of Histone Acetyltransferases P300/Cbp, Shenyou Nie, Fangrui Wu, Jingyu Wu, Xin Li, Chao Zhou, Yuan Yao, Yongcheng Song

Faculty, Staff and Students Publications

Acetylation of histone lysine residues by histone acetyltransferase (HAT) p300 and its paralog CBP play important roles in gene regulation in health and diseases. The HAT domain of p300/CBP has been found to be a potential drug target for cancer. Compound screening followed by structure-activity relationship studies yielded a novel series of 1,4-pyrazine-containing inhibitors of p300/CBP HAT with their IC50s as low as 1.4 μM. Enzyme kinetics and other studies support the most potent compound 29 is a competitive inhibitor of p300 HAT against the substrate histone. It exhibited a high selectivity for p300 and CBP, with negligible activity on …

A Conserved Mechanism For Hormesis In Molecular Systems, Sharon N. Greenwood, Regina G. Belz, Brian P. Weiser

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Hormesis refers to dose-response phenomena where low dose treatments elicit a response that is opposite the response observed at higher doses. Hormetic dose-response relationships have been observed throughout all of biology, but the underlying determinants of many reported hormetic dose-responses have not been identified. In this report, we describe a conserved mechanism for hormesis on the molecular level where low dose treatments enhance a response that becomes reduced at higher doses. The hormetic mechanism relies on the ability of protein homo-multimers to simultaneously interact with a substrate and a competitor on different subunits at low doses of competitor. In this …

Monkeypox: A Contemporary Review For Healthcare Professionals, Boghuma K Titanji, Bryan Tegomoh, Saman Nematollahi, Michael Konomos, Prathit A Kulkarni

Faculty, Staff and Students Publications

The ongoing 2022 multicountry outbreak of monkeypox is the largest in history to occur outside of Africa. Monkeypox is an emerging zoonotic disease that for decades has been viewed as an infectious disease with significant epidemic potential because of the increasing occurrence of human outbreaks in recent years. As public health entities work to contain the current outbreak, healthcare professionals globally are aiming to become familiar with the various clinical presentations and management of this infection. We present in this review an updated overview of monkeypox for healthcare professionals in the context of the ongoing outbreaks around the world.

Chronic Lung Allograft Dysfunction, Anupam Kumar, Puneet Singh Garcha

Faculty, Staff and Students Publications

Lung transplantation remains the only cure for selected patients with advanced irreversible lung diseases. More than 4000 lung transplants are performed worldwide annually. In the last two decades, significant advances have been made in this arena, the most impactful being a modest but improved survival of the recipients. Unfortunately majority of recipients still succumb to chronic lung allograft dysfunction (CLAD), and it remains the most common cause of death after the first year of transplantation. Below is a concise review of the current definition of CLAD, including the various phenotypes, and a brief discussion of the tools available for its …

Spatial Analysis Of Drug Absorption, Distribution, Metabolism, And Toxicology Using Mass Spectrometry Imaging, Michelle L Spruill, Mirjana Maletic-Savatic, Howard Martin, Feng Li, Xinli Liu

Faculty, Staff and Students Publications

Mass spectrometry imaging (MSI) is emerging as a powerful analytical tool for detection, quantification, and simultaneous spatial molecular imaging of endogenous and exogenous molecules via in situ mass spectrometry analysis of thin tissue sections without the requirement of chemical labeling. The MSI generates chemically specific and spatially resolved ion distribution information for administered drugs and metabolites, which allows numerous applications for studies involving various stages of drug absorption, distribution, metabolism, excretion, and toxicity (ADMET). MSI-based pharmacokinetic imaging analysis provides a histological context and cellular environment regarding dynamic drug distribution and metabolism processes, and facilitates the understanding of the spatial pharmacokinetics …

Activating Connexin43 Gap Junctions Primes Adipose Tissue For Therapeutic Intervention, Yi Zhu, Na Li, Mingyang Huang, Xi Chen, Yu A An, Jianping Li, Shangang Zhao, Jan-Bernd Funcke, Jianhong Cao, Zhenyan He, Qingzhang Zhu, Zhuzhen Zhang, Zhao V Wang, Lin Xu, Kevin W Williams, Chien Li, Kevin Grove, Philipp E Scherer

Faculty, Staff and Students Publications

Adipose tissue is a promising target for treating obesity and metabolic diseases. However, pharmacological agents usually fail to effectively engage adipocytes due to their extraordinarily large size and insufficient vascularization, especially in obese subjects. We have previously shown that during cold exposure, connexin43 (Cx43) gap junctions are induced and activated to connect neighboring adipocytes to share limited sympathetic neuronal input amongst multiple cells. We reason the same mechanism may be leveraged to improve the efficacy of various pharmacological agents that target adipose tissue. Using an adipose tissue-specific Cx43 overexpression mouse model, we demonstrate effectiveness in connecting adipocytes to augment metabolic …

Dual-Mode Tumor Imaging Using Probes That Are Responsive To Hypoxia-Induced Pathological Conditions, S A Amali S Subasinghe, Robia G Pautler, Md Abul Hassan Samee, Jason T Yustein, Matthew J Allen

Faculty, Staff and Students Publications

Hypoxia in solid tumors is associated with poor prognosis, increased aggressiveness, and strong resistance to therapeutics, making accurate monitoring of hypoxia important. Several imaging modalities have been used to study hypoxia, but each modality has inherent limitations. The use of a second modality can compensate for the limitations and validate the results of any single imaging modality. In this review, we describe dual-mode imaging systems for the detection of hypoxia that have been reported since the start of the 21st century. First, we provide a brief overview of the hallmarks of hypoxia used for imaging and the imaging modalities used …

Gain-Of-Signal Assays For Probing Inhibition Of Sars-Cov-2 Mpro/3clpro In Living Cells, Seyed Arad Moghadasi, Morgan A Esler, Yuka Otsuka, Jordan T Becker, Sofia N Moraes, Constance B Anderson, Srinivas Chamakuri, Christopher Belica, Chloe Wick, Daniel A Harki, Damian W Young, Louis Scampavia, Timothy P Spicer, Ke Shi, Hideki Aihara, William L Brown, Reuben S Harris

Faculty, Staff and Students Publications

The main protease, Mpro, of SARS-CoV-2 is required to cleave the viral polyprotein into precise functional units for virus replication and pathogenesis. Here, we report quantitative reporters for Mpro function in living cells in which protease inhibition by genetic or chemical methods results in robust signal readouts by fluorescence (enhanced green fluorescent protein [eGFP]) or bioluminescence (firefly luciferase). These gain-of-signal systems are scalable to high-throughput platforms for quantitative discrimination between Mpro mutants and/or inhibitor potencies as evidenced by validation of several reported inhibitors. Additional utility is shown by single Mpro amino acid variants and structural information combining to demonstrate that …

Crispr/Cas13 Effectors Have Differing Extents Of Off-Target Effects That Limit Their Utility In Eukaryotic Cells, Yuxi Ai, Dongming Liang, Jeremy E Wilusz

Faculty, Staff and Students Publications

CRISPR/Cas13 effectors have garnered increasing attention as easily customizable tools for detecting and depleting RNAs of interest. Near perfect complementarity between a target RNA and the Cas13-associated guide RNA is required for activation of Cas13 ribonuclease activity. Nonetheless, the specificity of Cas13 effectors in eukaryotic cells has been debated as the Cas13 nuclease domains can be exposed on the enzyme surface, providing the potential for promiscuous cleavage of nearby RNAs (so-called collateral damage). Here, using co-transfection assays in Drosophila and human cells, we found that the off-target effects of RxCas13d, a commonly used Cas13 effector, can be as strong as …

Variants In Asph Cause Exertional Heat Illness And Are Associated With Malignant Hyperthermia Susceptibility, Yukari Endo, Linda Groom, Alper Celik, Natalia Kraeva, Chang Seok Lee, Sung Yun Jung, Lois Gardner, Marie-Anne Shaw, Susan L Hamilton, Philip M Hopkins, Robert T Dirksen, Sheila Riazi, James J Dowling

Faculty, Staff and Students Publications

Exertional heat illness (EHI) and malignant hyperthermia (MH) are life threatening conditions associated with muscle breakdown in the setting of triggering factors including volatile anesthetics, exercise, and high environmental temperature. To identify new genetic variants that predispose to EHI and/or MH, we performed genomic sequencing on a cohort with EHI/MH and/or abnormal caffeine-halothane contracture test. In five individuals, we identified rare, pathogenic heterozygous variants in ASPH, a gene encoding junctin, a regulator of excitation-contraction coupling. We validated the pathogenicity of these variants using orthogonal pre-clinical models, CRISPR-edited C2C12 myotubes and transgenic zebrafish. In total, we demonstrate that ASPH variants represent …

Overexpression Of Foxf2 In Prostate Cancer Cells Causes An Increase In Cancer Cell Apoptosis And A Decrease In Proliferation, Vaughn Poon

Honors Projects

FOXF2 is a transcription factor that plays a crucial role in organ development, and recent studies have shown that it suppresses tumor growth and progression in mouse prostate models by attenuating the cancer-associated fibroblasts (CAF) phenotype and transcriptionally downregulating Cxcl5. However, the effects of FOXF2 overexpression in prostate cancer cells have not been extensively studied. Here, we investigate the impact of FOXF2 overexpression in prostate cancer cells and demonstrate that it leads to a significant increase in cell apoptosis and a decrease in proliferation. These findings suggest that FOXF2 may have potential as an immunotherapy drug target for prostate …

Evolutionary Action Of Mutations Reveals Antimicrobial Resistance Genes In Escherichia Coli, David C Marciano, Chen Wang, Teng-Kuei Hsu, Thomas Bourquard, Benu Atri, Ralf B Nehring, Nicholas S Abel, Elizabeth A Bowling, Taylor J Chen, Pamela D Lurie, Panagiotis Katsonis, Susan M Rosenberg, Christophe Herman, Olivier Lichtarge

Faculty, Staff and Students Publications

Since antibiotic development lags, we search for potential drug targets through directed evolution experiments. A challenge is that many resistance genes hide in a noisy mutational background as mutator clones emerge in the adaptive population. Here, to overcome this noise, we quantify the impact of mutations through evolutionary action (EA). After sequencing ciprofloxacin or colistin resistance strains grown under different mutational regimes, we find that an elevated sum of the evolutionary action of mutations in a gene identifies known resistance drivers. This EA integration approach also suggests new antibiotic resistance genes which are then shown to provide a fitness advantage …

Decoding The Pitx2-Controlled Genetic Network In Atrial Fibrillation, Jeffrey D Steimle, Francisco J Grisanti Canozo, Minjun Park, Zachary A Kadow, Md Abul Hassan Samee, James F Martin

Faculty, Staff and Students Publications

Atrial fibrillation (AF), the most common sustained cardiac arrhythmia and a major risk factor for stroke, often arises through ectopic electrical impulses derived from the pulmonary veins (PVs). Sequence variants in enhancers controlling expression of the transcription factor PITX2, which is expressed in the cardiomyocytes (CMs) of the PV and left atrium (LA), have been implicated in AF predisposition. Single nuclei multiomic profiling of RNA and analysis of chromatin accessibility combined with spectral clustering uncovered distinct PV- and LA-enriched CM cell states. Pitx2-mutant PV and LA CMs exhibited gene expression changes consistent with cardiac dysfunction through cell type-distinct, PITX2-directed, cis-regulatory …

Syphilis In The Esophagus, Ronan Allencherril, Paul Nicholls, Shilpa Jain, Robert Sealock, Priti Dangayach

Faculty, Staff and Students Publications

This report documents a unique case of syphilis with esophageal involvement. Such a presentation is exceedingly rare in the modern era, particularly among patients without human immunodeficiency virus. Most instances were documented in the 1900s and earlier. Our patient presented with months of odynophagia and recurrent oral lesions. He was found to have a sizeable esophageal ulcer on endoscopy, with biopsy confirming the diagnosis of syphilis. His symptoms quickly resolved with intramuscular penicillin. This case highlights the importance of keeping a broad differential for odynophagia and suspicious lesions, cutaneous or mucosal.

A Novel Crosstalk Between Autophagosomes And Phagosomes That Facilitates The Clearance Of Apoptotic Cells, Zheng Zhou, Omar Peña-Ramos

Faculty, Staff and Students Publications

During an animal's life, many cells undergo apoptosis, a form of genetically programmed cell death. These cells are swiftly engulfed by other cells through phagocytosis and subsequently degraded inside phagosomes. Phagocytosis and macroautophagy/autophagy are two different cellular events: whereas phagocytosis is a cell-eat-cell event, autophagy, or "self-eating", occurs within one cell, resulting in the enveloping of protein aggregates or damaged organelles within double-membrane autophagosomes. Despite this critical difference, these two events share common features: (1) both are means of safe garbage disposal; (2) both phagosomes and autophagosomes fuse to lysosomes, which drive the degradation of their contents; and (3) both …

A Concise Synthetic Method For Constructing 3-Substituted Piperazine-2-Acetic Acid Esters From 1,2-Diamines, Srinivas Chamakuri, Sunny Ann Tang, Kevin A Tran, Shiva Krishna Reddy Guduru, Peter K Bolin, Kevin R Mackenzie, Damian W Young

Faculty, Staff and Students Publications

We report a short synthetic route for synthesizing 2,3-substituted piperazine acetic acid esters. Optically pure amino acids were efficiently converted into 1,2-diamines that could be utilized to deliver the title 2,3-substituted piperazines in five steps with a high enantiomeric purity. The novel route facilitated, for the first time, the synthesis of 3-phenyl substituted-2-piperazine acetic acid esters that were difficult to achieve using other methods; however, in this case, the products underwent racemization.