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Articles 91 - 120 of 762

Full-Text Articles in Biochemistry, Biophysics, and Structural Biology

Crispr-Dipoff: An Interpretable Deep Learning Approach For Crispr Cas-9 Off-Target Prediction, Md Toufikuzzaman, Md Abul Hassan Samee, M Sohel Rahman Jan 2024

Crispr-Dipoff: An Interpretable Deep Learning Approach For Crispr Cas-9 Off-Target Prediction, Md Toufikuzzaman, Md Abul Hassan Samee, M Sohel Rahman

Faculty, Staff and Students Publications

CRISPR Cas-9 is a groundbreaking genome-editing tool that harnesses bacterial defense systems to alter DNA sequences accurately. This innovative technology holds vast promise in multiple domains like biotechnology, agriculture and medicine. However, such power does not come without its own peril, and one such issue is the potential for unintended modifications (Off-Target), which highlights the need for accurate prediction and mitigation strategies. Though previous studies have demonstrated improvement in Off-Target prediction capability with the application of deep learning, they often struggle with the precision-recall trade-off, limiting their effectiveness and do not provide proper interpretation of the complex decision-making process of …


Advancements In Revascularization Strategies For Acute Mesenteric Ischemia: A Comprehensive Review, Jacob J Gries, Hafeez Ul Hassan Virk, Bing Chen, Takashi Sakamoto, Mahboob Alam, Chayakrit Krittanawong Jan 2024

Advancements In Revascularization Strategies For Acute Mesenteric Ischemia: A Comprehensive Review, Jacob J Gries, Hafeez Ul Hassan Virk, Bing Chen, Takashi Sakamoto, Mahboob Alam, Chayakrit Krittanawong

Faculty, Staff and Students Publications

Even with modern advancements in the management of acute mesenteric ischemia over the past decade, morbidity and mortality remain high, and the best primary treatment modality is still debated amongst interventionalists. Traditionally, interventionalists have favored an open surgical approach but are now trending for endovascular interventions due to apparent reduced mortality and complications. Newer studies suggest hybrid approaches, and intestinal stroke centers may be superior to either strategy alone. This narrative review will explore the natural history of acute mesenteric ischemia with the aim of increasing interventionalist awareness of modern advancements in revascularization strategies for this devastating disease.


Kinase Inhibitor Pulldown Assay (Kip) For Clinical Proteomics, Alexander B Saltzman, Doug W Chan, Matthew V Holt, Junkai Wang, Eric J Jaehnig, Meenakshi Anurag, Purba Singh, Anna Malovannaya, Beom-Jun Kim, Matthew J Ellis Jan 2024

Kinase Inhibitor Pulldown Assay (Kip) For Clinical Proteomics, Alexander B Saltzman, Doug W Chan, Matthew V Holt, Junkai Wang, Eric J Jaehnig, Meenakshi Anurag, Purba Singh, Anna Malovannaya, Beom-Jun Kim, Matthew J Ellis

Faculty, Staff and Students Publications

Protein kinases are frequently dysregulated and/or mutated in cancer and represent essential targets for therapy. Accurate quantification is essential. For breast cancer treatment, the identification and quantification of the protein kinase ERBB2 is critical for therapeutic decisions. While immunohistochemistry (IHC) is the current clinical diagnostic approach, it is only semiquantitative. Mass spectrometry-based proteomics offers quantitative assays that, unlike IHC, can be used to accurately evaluate hundreds of kinases simultaneously. The enrichment of less abundant kinase targets for quantification, along with depletion of interfering proteins, improves sensitivity and thus promotes more effective downstream analyses. Multiple kinase inhibitors were therefore deployed as …


Chemical Catalysis Guides Structural Identification For The Major In Vivo Metabolite Of The Bet Inhibitor Jq1, Secondra Holmes, Prashi Jain, Kenneth Guzman Rodriguez, Jade Williams, Zhifeng Yu, Christian Cerda-Smith, Errol L G Samuel, James Campbell, John Michael Hakenjos, Diana Monsivais, Feng Li, Srinivas Chamakuri, Martin M Matzuk, Conrad Santini, Kevin R Mackenzie, Damian W Young Jan 2024

Chemical Catalysis Guides Structural Identification For The Major In Vivo Metabolite Of The Bet Inhibitor Jq1, Secondra Holmes, Prashi Jain, Kenneth Guzman Rodriguez, Jade Williams, Zhifeng Yu, Christian Cerda-Smith, Errol L G Samuel, James Campbell, John Michael Hakenjos, Diana Monsivais, Feng Li, Srinivas Chamakuri, Martin M Matzuk, Conrad Santini, Kevin R Mackenzie, Damian W Young

Faculty, Staff and Students Publications

The bromodomain inhibitor (+)-JQ1 is a highly validated chemical probe; however, it exhibits poor in vivo pharmacokinetics. To guide efforts toward improving its pharmacological properties, we identified the (+)-JQ1 primary metabolite using chemical catalysis methods. Treatment of (+)-JQ1 with tetrabutylammonium decatungstate under photochemical conditions resulted in selective formation of an aldehyde at the 2-position of the thiophene ring [(+)-JQ1-CHO], which was further reduced to the 2-hydroxymethyl analog [(+)-JQ1-OH]. Comparative LC/MS analysis of (+)-JQ1-OH to the product obtained from liver microsomes suggested (+)-JQ1-OH as the major metabolite of (+)-JQ1. The 2-thienyl position was then substituted to generate a trideuterated (−CD3, (+)-JQ1-D) …


Mechanism Of Anion Exchange And Small-Molecule Inhibition Of Pendrin, Lie Wang, Anthony Hoang, Eva Gil-Iturbe, Arthur Laganowsky, Matthias Quick, Ming Zhou Jan 2024

Mechanism Of Anion Exchange And Small-Molecule Inhibition Of Pendrin, Lie Wang, Anthony Hoang, Eva Gil-Iturbe, Arthur Laganowsky, Matthias Quick, Ming Zhou

Faculty, Staff and Students Publications

Pendrin (SLC26A4) is an anion exchanger that mediates bicarbonate (HCO3−) exchange for chloride (Cl−) and is crucial for maintaining pH and salt homeostasis in the kidney, lung, and cochlea. Pendrin also exports iodide (I−) in the thyroid gland. Pendrin mutations in humans lead to Pendred syndrome, causing hearing loss and goiter. Inhibition of pendrin is a validated approach for attenuating airway hyperresponsiveness in asthma and for treating hypertension. However, the mechanism of anion exchange and its inhibition by drugs remains poorly understood. We applied cryo-electron microscopy to determine structures of pendrin from Sus scrofa in the presence of either Cl−, …


Β2-Glycoprotein I Promotes The Clearance Of Circulating Mitochondria, Swapan Kumar Dasgupta, Jahnavi Gollamudi, Stefanie Rivera, Ross A Poche, Rolando E Rumbaut, Perumal Thiagarajan Jan 2024

Β2-Glycoprotein I Promotes The Clearance Of Circulating Mitochondria, Swapan Kumar Dasgupta, Jahnavi Gollamudi, Stefanie Rivera, Ross A Poche, Rolando E Rumbaut, Perumal Thiagarajan

Faculty, Staff and Students Publications

β2-glycoprotein I (β2-Gp1) is a cardiolipin-binding plasma glycoprotein. It is evolutionarily conserved from invertebrates, and cardiolipin-bound β2-Gp1 is a major target of antiphospholipid antibodies seen in autoimmune disorders. Cardiolipin is almost exclusively present in mitochondria, and mitochondria are present in circulating blood. We show that β2-Gp1 binds to cell-free mitochondria (CFM) in the circulation and promotes its phagocytosis by macrophages at physiological plasma concentrations. Exogenous CFM had a short circulation time of less than 10 minutes in mice. Following infusion of CFM, β2-Gp1-deficient mice had significantly higher levels of transfused mitochondria at 5 minutes (9.9 ± 6.4 pg/ml versus 4.0 …


Ibrutinib-Associated Cutaneous Mucormycosis Due To An Apophysomyces Species: Report Of A Case And Review Of The Literature, Trung Minh Nguyen, Eva Amenta, Lynne Chapman, Sarvari Yellapragada, Bhuvaneswari Krishnan, Jonathan Lim, Richard J Hamill Jan 2024

Ibrutinib-Associated Cutaneous Mucormycosis Due To An Apophysomyces Species: Report Of A Case And Review Of The Literature, Trung Minh Nguyen, Eva Amenta, Lynne Chapman, Sarvari Yellapragada, Bhuvaneswari Krishnan, Jonathan Lim, Richard J Hamill

Faculty, Staff and Students Publications

The use of ibrutinib, a Bruton tyrosine kinase inhibitor, has been associated with invasive fungal infections (IFIs). We describe a case of Apophysomyces infection associated with long-term use of ibrutinib for the treatment of chronic lymphocytic leukemia as well as perform a literature review of Mucormycosis infections in patients on ibrutinib. Our review found that the onset of IFI can occur within months to years of starting tyrosine kinase inhibitors. These reports provide a more complete picture of the risk of IFI while patients are on ibrutinib. Our case also demonstrates the utility of molecular techniques in the diagnosis of …


The Great Masquerade: Not All Coronary Artery Stenosis Are Created Equal, Prasanti A Kotta, Ajit K Koduri, Jeffrey Berman, Veronica V Rosen, Waleed T Kayani Jan 2024

The Great Masquerade: Not All Coronary Artery Stenosis Are Created Equal, Prasanti A Kotta, Ajit K Koduri, Jeffrey Berman, Veronica V Rosen, Waleed T Kayani

Faculty, Staff and Students Publications

We present the case of a 60-year-old male, with active smoking and cocaine use disorder, who reported progressive chest pain. Various anatomical and functional cardiac imaging, performed to further evaluate chest pain etiology, revealed changing severity and distribution of left main artery (LMA) stenosis, raising suspicion for vasospasm. Intracoronary nitroglycerin relieved the vasospasm, with resolution of the LMA pseudostenosis. A diagnosis of vasospastic angina (VA) led to starting appropriate medical therapy with lifestyle modification counselling. This case highlights VA, a frequently underdiagnosed etiology of angina pectoris. We discuss when to suspect VA, its appropriate work-up, and management.


Pre-Left Ventricular Assist Device Endoscopic Evaluation Does Not Reduce The Risk Of Later Gastrointestinal Bleeding: A Multicenter Study, Jiahao Peng, Samanthika Devalaraju, Mohamed Azab, William T Cates, Molly Stone, Jonathan Reichstein, Sneha Shaha, Subhasis Chatterjee, Andrew B Civitello, Mourad H Senussi, B Joseph Elmunzer, Michael Volk, Wasseem Skef Jan 2024

Pre-Left Ventricular Assist Device Endoscopic Evaluation Does Not Reduce The Risk Of Later Gastrointestinal Bleeding: A Multicenter Study, Jiahao Peng, Samanthika Devalaraju, Mohamed Azab, William T Cates, Molly Stone, Jonathan Reichstein, Sneha Shaha, Subhasis Chatterjee, Andrew B Civitello, Mourad H Senussi, B Joseph Elmunzer, Michael Volk, Wasseem Skef

Faculty, Staff and Students Publications

BACKGROUND: Gastrointestinal bleeding (GIB) is a common complication after placement of a left ventricular assist device (LVAD). Some institutions attempt to mitigate post-LVAD GIB using preoperative endoscopy. Our study evaluated whether preoperative endoscopy was associated with a lower risk of post-LVAD GIB.

METHODS: This was a multicenter cohort study of patients who underwent LVAD insertion from 2010-2019 at 3 academic sites. A total of 398 study participants were categorized based on whether they underwent preoperative endoscopy or not. The follow-up period was 1 year and the primary outcome was GIB. Secondary outcomes were severe bleeding and intraprocedural complications.

RESULTS: A …


Risk Factors, Incidence, And Outcomes Associated With Clinically Significant Airway Ischemia, Gloria Li, Zejian Liu, Marcelo Salan-Gomez, Emma Keeney, Ethan D'Silva, Babith Mankidy, Andres Leon, Aladdein Mattar, Abdusallam Elsennousi, Jennalee Coster, Anupam Kumar, Bruno Rodrigues, Meng Li, Alexis Shafii, Puneet Garcha, Gabriel Loor Jan 2024

Risk Factors, Incidence, And Outcomes Associated With Clinically Significant Airway Ischemia, Gloria Li, Zejian Liu, Marcelo Salan-Gomez, Emma Keeney, Ethan D'Silva, Babith Mankidy, Andres Leon, Aladdein Mattar, Abdusallam Elsennousi, Jennalee Coster, Anupam Kumar, Bruno Rodrigues, Meng Li, Alexis Shafii, Puneet Garcha, Gabriel Loor

Faculty, Staff and Students Publications

Airway complications following lung transplantation remain an important cause of morbidity and mortality. We aimed to identify the incidence, risk factors and outcomes associated with clinically significant airway ischemia (CSAI) in our center. We reviewed 217 lung transplants (386 airway anastomoses) performed at our institution between February 2016 and December 2020. Airway images were graded using the 2018 ISHLT grading guidelines modified slightly for retrospective analysis. Airways were considered to have CSAI if they developed ischemia severity >B2, stenosis >50%, and/or any degree of dehiscence within 6-months of transplant. Regression analyses were used to evaluate outcomes and risk factors for …


Using Noninvasive Clinical Parameters To Predict Mortality And Morbidity After Cardiac Interventions In Patients With Cirrhosis: A Systematic Review, Christo Mathew, Ankur Patel, George Cholankeril, Avegail Flores, Ruben Hernaez Jan 2024

Using Noninvasive Clinical Parameters To Predict Mortality And Morbidity After Cardiac Interventions In Patients With Cirrhosis: A Systematic Review, Christo Mathew, Ankur Patel, George Cholankeril, Avegail Flores, Ruben Hernaez

Faculty, Staff and Students Publications

BACKGROUND: Cardiovascular disease commonly affects advanced liver disease patients. They undergo cardiac interventions to improve cardiac outcomes. Cirrhosis increases complication risk, including bleeding, renal and respiratory failure, and further decompensation, including death, posing a clinical dilemma to proceduralists. Predicting outcomes is crucial in managing patients with cirrhosis. Our aim was to systematically review clinical parameters to assess the mortality and complication risk in patients with cirrhosis undergoing cardiac interventions.

METHODS: We searched cirrhosis and cardiovascular intervention terminology in PubMed and Excerpta Medica Database (EMBASE) from inception to January 8, 2023. We included studies reporting clinical scores (e.g. Model for End-stage …


Klebsiella Pneumoniae Carbapenemase Variant 44 Acquires Ceftazidime-Avibactam Resistance By Altering The Conformation Of Active-Site Loops, Zhizeng Sun, Hanfeng Lin, Liya Hu, Neetu Neetu, Banumathi Sankaran, Jin Wang, B V Venkataram Prasad, Timothy Palzkill Jan 2024

Klebsiella Pneumoniae Carbapenemase Variant 44 Acquires Ceftazidime-Avibactam Resistance By Altering The Conformation Of Active-Site Loops, Zhizeng Sun, Hanfeng Lin, Liya Hu, Neetu Neetu, Banumathi Sankaran, Jin Wang, B V Venkataram Prasad, Timothy Palzkill

Faculty, Staff and Students Publications

Klebsiella pneumoniae carbapenemase 2 (KPC-2) is an important source of drug resistance as it can hydrolyze and inactivate virtually all β-lactam antibiotics. KPC-2 is potently inhibited by avibactam via formation of a reversible carbamyl linkage of the inhibitor with the catalytic serine of the enzyme. However, the use of avibactam in combination with ceftazidime (CAZ-AVI) has led to the emergence of CAZ-AVI-resistant variants of KPC-2 in clinical settings. One such variant, KPC-44, bears a 15 amino acid duplication in one of the active-site loops (270-loop). Here, we show that the KPC-44 variant exhibits higher catalytic efficiency in hydrolyzing ceftazidime, lower …


An Interactive, Case-Based Workshop On The Patient Experience For Internal Medicine Residents, Julian Swanson, Doris Lin, Kristen A Staggers, Priti Dangayach Jan 2024

An Interactive, Case-Based Workshop On The Patient Experience For Internal Medicine Residents, Julian Swanson, Doris Lin, Kristen A Staggers, Priti Dangayach

Faculty, Staff and Students Publications

INTRODUCTION: The technological revolution has narrowed the information gap between physician and patient. This has led to an evolution in medicine from paternalistic to patient-centric, with health care systems now prioritizing patient experience to achieve higher satisfaction scores. Therefore, it is imperative to start early in educating trainees on how to best address the holistic needs of the patient while also delivering high-quality care.

METHODS: We implemented a 1-hour workshop that was repeated weekly over 8 weeks to capture all internal medicine residents in our program. During the workshop, we reviewed the historical evolution of patient care from paternalistic to …


Inhibition Of Src-3 As A Potential Therapeutic Strategy For Aggressive Mantle Cell Lymphoma, Imani Bijou, Yang Liu, Dong Lu, Jianwei Chen, Shelby Sloan, Lapo Alinari, David M Lonard, Bert W O'Malley, Michael Wang, Jin Wang Jan 2024

Inhibition Of Src-3 As A Potential Therapeutic Strategy For Aggressive Mantle Cell Lymphoma, Imani Bijou, Yang Liu, Dong Lu, Jianwei Chen, Shelby Sloan, Lapo Alinari, David M Lonard, Bert W O'Malley, Michael Wang, Jin Wang

Faculty, Staff and Students Publications

Mantle cell lymphoma (MCL) has a poor prognosis and high relapse rates despite current therapies, necessitating novel treatment regimens. Inhibition of SRC-3 show effectiveness in vivo and in vitro in other B cell lymphomas. Additionally, previous studies have shown that SRC-3 is highly expressed in the lymph nodes of B cell non-Hodgkin's lymphoma patients, suggesting SRC-3 may play a role in the progression of B cell lymphoma. This study aimed to investigate novel SRC-3 inhibitors, SI-10 and SI-12, in mantle cell lymphoma. The cytotoxic effects of SI-10 and SI-12 were evaluated in vitro and demonstrated dose-dependent cytotoxicity in a panel …


Targeting Eif4a Triggers An Interferon Response To Synergize With Chemotherapy And Suppress Triple-Negative Breast Cancer, Na Zhao, Elena B Kabotyanski, Alexander B Saltzman, Anna Malovannaya, Xueying Yuan, Lucas C Reineke, Nadia Lieu, Yang Gao, Diego A Pedroza, Sebastian J Calderon, Alex J Smith, Clark Hamor, Kazem Safari, Sara Savage, Bing Zhang, Jianling Zhou, Luisa M Solis, Susan G Hilsenbeck, Cheng Fan, Charles M Perou, Jeffrey M Rosen Dec 2023

Targeting Eif4a Triggers An Interferon Response To Synergize With Chemotherapy And Suppress Triple-Negative Breast Cancer, Na Zhao, Elena B Kabotyanski, Alexander B Saltzman, Anna Malovannaya, Xueying Yuan, Lucas C Reineke, Nadia Lieu, Yang Gao, Diego A Pedroza, Sebastian J Calderon, Alex J Smith, Clark Hamor, Kazem Safari, Sara Savage, Bing Zhang, Jianling Zhou, Luisa M Solis, Susan G Hilsenbeck, Cheng Fan, Charles M Perou, Jeffrey M Rosen

Faculty, Staff and Students Publications

Protein synthesis is frequently dysregulated in cancer and selective inhibition of mRNA translation represents an attractive cancer therapy. Here, we show that therapeutically targeting the RNA helicase eIF4A with zotatifin, the first-in-class eIF4A inhibitor, exerts pleiotropic effects on both tumor cells and the tumor immune microenvironment in a diverse cohort of syngeneic triple-negative breast cancer (TNBC) mouse models. Zotatifin not only suppresses tumor cell proliferation but also directly repolarizes macrophages toward an M1-like phenotype and inhibits neutrophil infiltration, which sensitizes tumors to immune checkpoint blockade. Mechanistic studies revealed that zotatifin reprograms the tumor translational landscape, inhibits the translation of Sox4 …


Biomarkers For Heart Failure Prediction And Prevention, Prasanti Alekhya Kotta, Vijay Nambi, Biykem Bozkurt Dec 2023

Biomarkers For Heart Failure Prediction And Prevention, Prasanti Alekhya Kotta, Vijay Nambi, Biykem Bozkurt

Faculty, Staff and Students Publications

Heart failure (HF) is a global pandemic affecting over 64 million people worldwide. Its prevalence is on an upward trajectory, with associated increasing healthcare expenditure. Organizations including the American College of Cardiology (ACC) and the American Heart Association (AHA) have identified HF prevention as an important focus. Recently, the ACC/AHA/Heart Failure Society of America (HFSA) Guidelines on heart failure were updated with a new Class IIa, Level of Evidence B recommendation for biomarker-based screening in patients at risk of developing heart failure. In this review, we evaluate the studies that have assessed the various roles and contributions of biomarkers in …


Do We Still Need Aspirin In Coronary Artery Disease?, Muhammad Haisum Maqsood, Glenn N Levine, Neal D Kleiman, David Hasdai, Barry F Uretsky, Yochai Birnbaum Dec 2023

Do We Still Need Aspirin In Coronary Artery Disease?, Muhammad Haisum Maqsood, Glenn N Levine, Neal D Kleiman, David Hasdai, Barry F Uretsky, Yochai Birnbaum

Faculty, Staff and Students Publications

Aspirin has for some time been used as a first-line treatment for acute coronary syndromes, including ST-elevation myocardial infarction, for secondary prevention of established coronary disease, and for primary prevention in patients at risk of coronary artery disease. Although aspirin has been in use for decades, the available evidence for its efficacy largely predates the introduction of other drugs, such as statins and P2Y12 inhibitors. Based on recent trials, the recommendation for aspirin use as primary prevention has been downgraded. In addition, P2Y12 inhibitors given as a single antiplatelet therapy have been associated with a lower incidence of bleeding than …


A Cancer-Specific Study On The Differentially Expressed Protein-Protein Interactions Of Fumarate Hydratase, Sydney Lac Dec 2023

A Cancer-Specific Study On The Differentially Expressed Protein-Protein Interactions Of Fumarate Hydratase, Sydney Lac

Dissertations and Theses (Open Access)

Fumarate hydratase (FH) is an enzyme used in the Krebs Cycle to convert fumarate to malate, and it is controlled by the FH gene. In this paper, we will investigate its role in Uterine Corpus Endometrial Carcinoma (UCEC) and how FH-deficient cells affect tumorigenesis. It is well-established that FH has been extensively studied in connection with renal cell carcinoma, skin and uterine leiomyomas, pheochromocytoma, and paraganglioma. However, we aim to construct an interaction network of significant genes related to the FH gene under conditions of FH deficiency in the Kreb Cycle. Creating an interactive network that illustrates the interconnectedness of …


Case Sampling Vs Universal Review For Evaluating Hospital Postoperative Mortality In Us Surgical Quality Improvement Programs, Vivi W Chen, Alexis P Chidi, Tracey Rosen, Yongquan Dong, Peter A Richardson, Jennifer Kramer, David A Axelrod, Laura A Petersen, Nader N Massarweh Dec 2023

Case Sampling Vs Universal Review For Evaluating Hospital Postoperative Mortality In Us Surgical Quality Improvement Programs, Vivi W Chen, Alexis P Chidi, Tracey Rosen, Yongquan Dong, Peter A Richardson, Jennifer Kramer, David A Axelrod, Laura A Petersen, Nader N Massarweh

Faculty, Staff and Students Publications

IMPORTANCE: Representative surgical case sampling, rather than universal review, is used by US Department of Veterans Affairs (VA) and private-sector national surgical quality improvement (QI) programs to assess program performance and to inform local QI and performance improvement efforts. However, it is unclear whether case sampling is robust for identifying hospitals with safety or quality concerns.

OBJECTIVE: To evaluate whether the sampling strategy used by several national surgical QI programs provides hospitals with data that are representative of their overall quality and safety, as measured by 30-day mortality.

DESIGN, SETTING, AND PARTICIPANTS: This comparative effectiveness study was a national, hospital-level …


Contemporary Use Of Coronary Physiology In Cardiology, Ayman Elbadawi, Ramy Sedhom, Mohamed Ghoweba, Abdelazeem Mohamed Etewa, Waleed Kayani, Faisal Rahman Dec 2023

Contemporary Use Of Coronary Physiology In Cardiology, Ayman Elbadawi, Ramy Sedhom, Mohamed Ghoweba, Abdelazeem Mohamed Etewa, Waleed Kayani, Faisal Rahman

Faculty, Staff and Students Publications

Coronary angiography has a limited ability to predict the functional significance of intermediate coronary lesions. Hence, physiological assessment of coronary lesions, via fractional flow reserve (FFR) or instantaneous wave-free ratio (iFR), has been introduced to determine their functional significance. An accumulating body of evidence has consolidated the role of physiology-guided revascularization, particularly among patients with stable ischemic heart disease. The use of FFR or iFR to guide decision-making in patients with stable ischemic heart disease and intermediate coronary lesions received a class I recommendation from major societal guidelines. Nevertheless, the role of coronary physiology testing is less clear among certain …


Development Of Novel Methods To Study Host-Microbe Interactions In The Larval Zebrafish Gastrointestinal Tract, Anh K. Trinh Nguyen Dec 2023

Development Of Novel Methods To Study Host-Microbe Interactions In The Larval Zebrafish Gastrointestinal Tract, Anh K. Trinh Nguyen

Dissertations and Theses (Open Access)

The dynamic nature and inaccessible location of the intestine pose significant challenges to the study of intestinal physiology and pathology. Zebrafish larvae, possessing optical transparency and genetic tractability, offer an accessible and clinically relevant model for investigating dynamic events in the intestine via time-lapse imaging. In the first part of this work, I discuss our efforts to optimize the parameters of a foodborne infection assay using paramecia as a vehicle. This method provides an effective, high-throughput alternative to infection via immersion or oral gavage, and replicates the most common route of transmission of gastrointestinal (GI) infection in humans. The foodborne …


A Signal To Divide: Apoptotic Extracellular Vesicles As Carriers Of Mitogenic And Immunogenic Signals, Safia Essien, Safia Essien Dec 2023

A Signal To Divide: Apoptotic Extracellular Vesicles As Carriers Of Mitogenic And Immunogenic Signals, Safia Essien, Safia Essien

Dissertations and Theses (Open Access)

Efficient replacement of dead cells in epithelial tissue is crucial for maintaining barrier function and tissue homeostasis. Apoptotic cells can signal to neighboring cells to stimulate proliferation and compensate for cell loss and maintain overall cell numbers in normal physiology and cancer. While dying cells can transmit instructive cues to neighboring cells, the molecular mechanisms that induce cell division are not well understood. Recent evidence suggests that apoptotic bodies (ABs) or apoptotic extracellular vesicles (AEVs) mediate cell-to-cell communication and carry diverse biologically active cellular cargo which can influence cell proliferation. This dissertation visualizes and characterizes AEVs in larval zebrafish and …


Evaluation Of Potential Role Of R-Loop And G-Quadruplex Dna In The Fragility Of C-Myc During Chromosomal Translocation Associated With Burkitt's Lymphoma, Nitu Kumari, Kohal Das, Shivangi Sharma, Sumedha Dahal, Sagar Sanjiv Desai, Urbi Roy, Anju Sharma, Meghana Manjunath, Vidya Gopalakrishnan, S T Retheesh, Saniya M Javadekar, Bibha Choudhary, Sathees C Raghavan Dec 2023

Evaluation Of Potential Role Of R-Loop And G-Quadruplex Dna In The Fragility Of C-Myc During Chromosomal Translocation Associated With Burkitt's Lymphoma, Nitu Kumari, Kohal Das, Shivangi Sharma, Sumedha Dahal, Sagar Sanjiv Desai, Urbi Roy, Anju Sharma, Meghana Manjunath, Vidya Gopalakrishnan, S T Retheesh, Saniya M Javadekar, Bibha Choudhary, Sathees C Raghavan

Faculty, Staff and Student Publications

t(8;14) translocation is the hallmark of Burkitt's lymphoma and results in c-MYC deregulation. During the translocation, c-MYC gene on chromosome 8 gets juxtaposed to the Ig switch regions on chromosome 14. Although the promoter of c-MYC has been investigated for its mechanism of fragility, little is known about other c-MYC breakpoint regions. We have analyzed the translocation break points at the exon 1/intron 1 of c-MYC locus from patients with Burkitt's lymphoma. Results showed that the breakpoint region, when present on a plasmid, could fold into an R-loop confirmation in a transcription-dependent manner. Sodium bisulfite modification assay revealed significant single-strandedness …


Single-Cell Multiomics Of The Human Retina Reveals Hierarchical Transcription Factor Collaboration In Mediating Cell Type-Specific Effects Of Genetic Variants On Gene Regulation, Jun Wang, Xuesen Cheng, Qingnan Liang, Leah A Owen, Jiaxiong Lu, Yiqiao Zheng, Meng Wang, Shiming Chen, Margaret M Deangelis, Yumei Li, Rui Chen Nov 2023

Single-Cell Multiomics Of The Human Retina Reveals Hierarchical Transcription Factor Collaboration In Mediating Cell Type-Specific Effects Of Genetic Variants On Gene Regulation, Jun Wang, Xuesen Cheng, Qingnan Liang, Leah A Owen, Jiaxiong Lu, Yiqiao Zheng, Meng Wang, Shiming Chen, Margaret M Deangelis, Yumei Li, Rui Chen

Faculty, Staff and Students Publications

BACKGROUND: Systematic characterization of how genetic variation modulates gene regulation in a cell type-specific context is essential for understanding complex traits. To address this question, we profile gene expression and chromatin accessibility in cells from healthy retinae of 20 human donors through single-cell multiomics and genomic sequencing.

RESULTS: We map eQTL, caQTL, allelic-specific expression, and allelic-specific chromatin accessibility in major retinal cell types. By integrating these results, we identify and characterize regulatory elements and genetic variants effective on gene regulation in individual cell types. The majority of identified sc-eQTLs and sc-caQTLs display cell type-specific effects, while the cis-elements containing genetic …


In Vivo Volumetric Depth-Resolved Imaging Of Cilia Metachronal Waves Using Dynamic Optical Coherence Tomography, Tian Xia, Kohei Umezu, Deirdre M Scully, Shang Wang, Irina V Larina Nov 2023

In Vivo Volumetric Depth-Resolved Imaging Of Cilia Metachronal Waves Using Dynamic Optical Coherence Tomography, Tian Xia, Kohei Umezu, Deirdre M Scully, Shang Wang, Irina V Larina

Faculty, Staff and Students Publications

Motile cilia are dynamic hair-like structures covering epithelial surfaces in multiple organs. The periodic coordinated beating of cilia creates waves propagating along the surface, known as the metachronal waves, which transport fluids and mucus along the epithelium. Motile ciliopathies result from disrupted coordinated cilia beating and are associated with serious clinical complications, including reproductive disorders. Despite the recognized clinical significance, research of cilia dynamics is extremely limited. Here, we present quantitative imaging of cilia metachronal waves volumetrically through tissue layers using dynamic optical coherence tomography (OCT). Our method relies on spatiotemporal mapping of the phase of intensity fluctuations in OCT …


Discovery, Structure-Activity Relationship And In Vitro Anticancer Activity Of Small-Molecule Inhibitors Of The Protein-Protein Interactions Between Af9/Enl And Af4 Or Dot1l, Xin Li, Xiaowei Wu, Shenyou Nie, Jidong Zhao, Yuan Yao, Fangrui Wu, Chandra Bhushan Mishra, Md Ashraf-Uz-Zaman, Bala Krishna Moku, Yongcheng Song Nov 2023

Discovery, Structure-Activity Relationship And In Vitro Anticancer Activity Of Small-Molecule Inhibitors Of The Protein-Protein Interactions Between Af9/Enl And Af4 Or Dot1l, Xin Li, Xiaowei Wu, Shenyou Nie, Jidong Zhao, Yuan Yao, Fangrui Wu, Chandra Bhushan Mishra, Md Ashraf-Uz-Zaman, Bala Krishna Moku, Yongcheng Song

Faculty, Staff and Students Publications

Simple Summary

Chromosomal translocations involving the mixed lineage leukemia (MLL) gene generate potent fusion oncogenes and cause acute myeloid leukemia or lymphocytic leukemia, which account for ~75% infant and 5–10% child/adult acute leukemia cases with a poor prognosis (5-year survival rates < 45%). Protein–protein interactions between the most frequent MLL fusion partner proteins AF9/ENL and AF4 or histone methyltransferase DOT1L are critical to malignant gene expression and are therefore a potential drug target for cancer. Compound screening followed by medicinal chemistry studies identified several novel small-molecule inhibitors showing strong inhibition of these protein–protein interactions, significant suppression of characteristic gene expression, and robust cellular anticancer activities with negligible cytotoxicity. These compounds are useful chemical probes for biological studies of these protein–protein interactions, as well as pharmacological leads for further drug development against MLL-rearranged and other leukemias.

Abstract

Chromosomal translocations involving the mixed lineage leukemia (MLL) gene cause 5–10% acute leukemias with poor clinical outcomes. Protein–protein interactions (PPI) between the most frequent MLL fusion partner proteins AF9/ENL and AF4 or histone methyltransferase DOT1L are drug targets for MLL-rearranged (MLL-r) leukemia. Several benzothiophene-carboxamide compounds were identified as novel inhibitors of these PPIs with IC50 values as …


An Automated Respiratory Data Pipeline For Waveform Characteristic Analysis, Savannah Lusk, Christopher S Ward, Andersen Chang, Avery Twitchell-Heyne, Shaun Fattig, Genevera Allen, Joanna L Jankowsky, Russell S Ray Nov 2023

An Automated Respiratory Data Pipeline For Waveform Characteristic Analysis, Savannah Lusk, Christopher S Ward, Andersen Chang, Avery Twitchell-Heyne, Shaun Fattig, Genevera Allen, Joanna L Jankowsky, Russell S Ray

Faculty, Staff and Students Publications

Comprehensive and accurate analysis of respiratory and metabolic data is crucial to modelling congenital, pathogenic and degenerative diseases converging on autonomic control failure. A lack of tools for high-throughput analysis of respiratory datasets remains a major challenge. We present Breathe Easy, a novel open-source pipeline for processing raw recordings and associated metadata into operative outcomes, publication-worthy graphs and robust statistical analyses including QQ and residual plots for assumption queries and data transformations. This pipeline uses a facile graphical user interface for uploading data files, setting waveform feature thresholds and defining experimental variables. Breathe Easy was validated against manual selection by …


Risk-Adjusted Cumulative Sum For Early Detection Of Hospitals With Excess Perioperative Mortality, Vivi W Chen, Alexis P Chidi, Yongquan Dong, Peter A Richardson, David A Axelrod, Laura A Petersen, Nader N Massarweh Nov 2023

Risk-Adjusted Cumulative Sum For Early Detection Of Hospitals With Excess Perioperative Mortality, Vivi W Chen, Alexis P Chidi, Yongquan Dong, Peter A Richardson, David A Axelrod, Laura A Petersen, Nader N Massarweh

Faculty, Staff and Students Publications

IMPORTANCE: National surgical quality improvement programs lack tools for early detection of quality or safety concerns, which risks patient safety because of delayed recognition of poor performance.

OBJECTIVE: To compare the risk-adjusted cumulative sum (CUSUM) with episodic evaluation for early detection of hospitals with excess perioperative mortality.

DESIGN, SETTING, AND PARTICIPANTS: National, observational, hospital-level, comparative effectiveness study of 697 566 patients. Identification of hospitals with excess, risk-adjusted, quarterly 30-day mortality using observed to expected ratios (ie, current criterion standard in the Veterans Affairs Surgical Quality Improvement Program) was compared with the risk-adjusted CUSUM. Patients included in the study underwent a …


Endoscopic Vacuum Therapy For Treatment Of Spontaneous And Iatrogenic Upper Gastrointestinal Defects, Kavea Panneerselvam, Jake S Jacob, Ronald E Samuel, Andy Tau, Gyanprakash A Ketwaroo, Wasif M Abidi, Robert J Sealock Nov 2023

Endoscopic Vacuum Therapy For Treatment Of Spontaneous And Iatrogenic Upper Gastrointestinal Defects, Kavea Panneerselvam, Jake S Jacob, Ronald E Samuel, Andy Tau, Gyanprakash A Ketwaroo, Wasif M Abidi, Robert J Sealock

Faculty, Staff and Students Publications

BACKGROUND/AIMS: Endoscopic vacuum therapy (EVT) can heal a variety of defects within the gastrointestinal (GI) tract via applying negative pressure, which reduces the defect size, aspirates the infected fluid, and promotes granulation tissue. Here we present our experience with EVT as it relates to both spontaneous and iatrogenic upper GI tract perforations, leaks, and fistulas.

METHODS: This retrospective study was conducted at four large hospital centers. All patients who underwent EVT between June 2018 and March 2021 were included. Data on multiple variables were collected, including demographics, defect size and location, number and intervals of EVT exchanges, technical success, and …


Increasing Glutathione Levels By A Novel Posttranslational Mechanism Inhibits Neuronal Hyperexcitability, Ashwini Sri Hari, Rajeswari Banerji, Li-Ping Liang, Ruth E Fulton, Christopher Quoc Huynh, Timothy Fabisiak, Pallavi Bhuyan Mcelroy, James R Roede, Manisha Patel Nov 2023

Increasing Glutathione Levels By A Novel Posttranslational Mechanism Inhibits Neuronal Hyperexcitability, Ashwini Sri Hari, Rajeswari Banerji, Li-Ping Liang, Ruth E Fulton, Christopher Quoc Huynh, Timothy Fabisiak, Pallavi Bhuyan Mcelroy, James R Roede, Manisha Patel

Faculty, Staff and Students Publications

Glutathione (GSH) depletion, and impaired redox homeostasis have been observed in experimental animal models and patients with epilepsy. Pleiotropic strategies that elevate GSH levels via transcriptional regulation have been shown to significantly decrease oxidative stress and seizure frequency, increase seizure threshold, and rescue certain cognitive deficits. Whether elevation of GSH per se alters neuronal hyperexcitability remains unanswered. We previously showed that thiols such as dimercaprol (DMP) elevate GSH via post-translational activation of glutamate cysteine ligase (GCL), the rate limiting GSH biosynthetic enzyme. Here, we asked if elevation of cellular GSH by DMP altered neuronal hyperexcitability in-vitro and in-vivo. Treatment of …