Digital Commons Network^™

Mechanisms Underlying The Antiarrhythmic Effect Of Arumenamide-787 In Experimental Models Of The J Wave Syndromes And Hypothermia, José M. Di Diego, Hector Barajas-Martinez, Robert Cox, Victoria M Robinson, Joseph Jung, Mohamed Fouda, Mena Abdelsayed, Peter C Ruben, Charles Antzelevitch

Department of Medicine Faculty Papers

BACKGROUND: Brugada (BrS) and early repolarization syndromes (ERS), the so-called J wave syndromes (JWS), are associated with life-threatening ventricular arrhythmias. Pharmacologic approaches to therapy are currently limited. In this study, we examine the effects of ARumenamide-787 (AR-787) to suppress the electrocardiographic and arrhythmic manifestations of JWS and hypothermia.

METHODS: We studied the effects of AR-787 on INa and IKr in HEK-293 cells stably expressing the α- and β1-subunits of the cardiac (NaV1.5) sodium channel and hERG channel, respectively. In addition, we studied its effect on Ito, INa and ICa in dissociated canine ventricular myocytes along with action potentials and ECG …

Antibodies For Β2-Microglobulin And The Heavy Chains Of Hla-E, Hla-F, And Hla-G Reflect The Hla-Variants On Activated Immune Cells And Phases Of Disease Progression In Rheumatoid Arthritis Patients Under Treatment, Mepur H. Ravindranath, Narendranath M. Ravindranath, Carly J. Amato-Menker, Fatiha El Hilali, Senthamil R. Selvan, Edward J Filippone, Luis Eduardo Morales-Buenrostro

Department of Medicine Faculty Papers

Rheumatoid arthritis (RA) is a progressive, inflammatory, autoimmune, symmetrical polyarticular arthritis. It is characterized by synovial infiltration and activation of several types of immune cells, culminating in their apoptosis and antibody generation against "altered" autoantigens. β2-microglobulin (β2m)-associated heavy chains (HCs) of HLA antigens, also known as closed conformers (Face-1), undergo "alteration" during activation of immune cells, resulting in β2m-free structural variants, including monomeric open conformers (Face-2) that are capable of dimerizing as either homodimers (Face-3) or as heterodimers (Face-4). β2m-free HCs uncover the cryptic epitopes that can elicit antibodies (Abs). We report here the levels of IgM and IgG Abs …

Perioperative Outcomes Of Patients With Bleeding Disorders Undergoing Major Surgery At An Academic Hemophilia Treatment Center, Ruben Rhoades, Zachary French, Amy Yang, Karen Walsh, Douglass A. Drelich, Steven E. Mckenzie

Department of Medicine Faculty Papers

Persons with bleeding disorders (PwBD) are at high risk for bleeding with invasive procedures. However, the risk of bleeding in PwBD undergoing major surgery and outcomes of patients managed perioperatively at a hemophilia treatment center (HTC) are not well described. We performed a retrospective review of surgical outcomes among PwBD undergoing major surgery between January 1st, 2017 and December 31st, 2019 at the Cardeza Foundation Hemophilia and Thrombosis Center in Philadelphia, PA. The primary outcome was postoperative bleeding, assessed according to the ISTH-SSC's 2010 definition. Secondary outcomes included use of unplanned postoperative hemostatic therapy, LOS, and 30-day readmission rate. Results …

Role Of Extracellular Vesicles In Glia-Neuron Intercellular Communication, Shahzad Ahmad, Rohit K Srivastava, Pratibha Singh, Ulhas P. Naik, Amit K Srivastava

Department of Medicine Faculty Papers

Cross talk between glia and neurons is crucial for a variety of biological functions, ranging from nervous system development, axonal conduction, synaptic transmission, neural circuit maturation, to homeostasis maintenance. Extracellular vesicles (EVs), which were initially described as cellular debris and were devoid of biological function, are now recognized as key components in cell-cell communication and play a critical role in glia-neuron communication. EVs transport the proteins, lipids, and nucleic acid cargo in intercellular communication, which alters target cells structurally and functionally. A better understanding of the roles of EVs in glia-neuron communication, both in physiological and pathological conditions, can aid …

Ramifications Of The Hla-I Allelic Reactivity Of Anti-Hla-E*01:01 And Anti-Hla-E*01:03 Heavy Chain Monoclonal Antibodies In Comparison With Anti-Hla-I Igg Reactivity In Non-Alloimmunized Males, Melanoma-Vaccine Recipients, And End-Stage Renal Disease Patients, Mepur H Ravindranath, Narendranath M Ravindranath, Fatiha El Hilali, Senthamil R Selvan, Edward J Filippone

Department of Medicine Faculty Papers

Serum anti-HLA-I IgG are present in non-alloimmunized males, cancer patients, and transplant recipients. Anti-HLA-I antibodies are also present in intravenous immunoglobulin (IVIg), prepared from the plasma of thousands of healthy donors. However, the HLA-Ia reactivity of IVIg diminishes markedly after passing through HLA-E HC-affinity columns, suggesting that the HLA-I reactivity is due to antibodies formed against HLA-E. Hence, we examined whether anti-HLA-E antibodies can react to HLA-I alleles. Monoclonal IgG antibodies (mAbs) against HCs of two HLA-E alleles were generated in Balb/C mice. The antibodies were analyzed using multiplex bead assays on a Luminex platform for HLA-I reactivity. Beads coated …

Four Faces Of Cell-Surface Hla Class-I: Their Antigenic And Immunogenic Divergence Generating Novel Targets For Vaccines, Mepur H Ravindranath, Narendranath M Ravindranath, Senthamil R Selvan, Edward J Filippone, Carly J Amato-Menker, Fatiha El Hilali

Department of Medicine Faculty Papers

Leukocyte cell-surface HLA-I molecules, involved in antigen presentation of peptides to CD8+ T-cells, consist of a heavy chain (HC) non-covalently linked to β2-microglobulin (β2m) (Face-1). The HC amino acid composition varies across all six isoforms of HLA-I, while that of β2m remains the same. Each HLA-allele differs in one or more amino acid sequences on the HC α1 and α2 helices, while several sequences among the three helices are conserved. HCs without β2m (Face-2) are also observed on human cells activated by malignancy, viral transformation, and cytokine or chemokine-mediated inflammation. In the absence of β2m, the monomeric Face-2 exposes immunogenic …

Filling Gaps And Setting Boundaries: Examining Utilization Of Health And Social Services At Jeffhope Student Run Clinics., Roy Wang, Amanda Guth, Alyssa Tate, Michele Ly, James D. Plumb Md, Mph

Department of Medicine Faculty Papers

The objective of this study was to describe the frequency that healthcare and social support services offered by JeffHOPE, a student run clinic for people experiencing homelessness in Philadelphia, PA, were utilized by patients. This study also aimed to investigate where patients would seek medical care on a given day had they not been able to access JeffHOPE. This study was conducted via mixed methods consisting of retrospective chart review of patient encounter records and a patient survey conducted weekly throughout 2019, both at a single clinic site, and retrospective chart review of January through March 2020 records at 5 …

Apixaban Discontinuation For Invasive Or Major Surgical Procedures (Adios): A Prospective Cohort Study., Geno J. Merli, Walter K. Kraft, Luis H. Eraso, Taki Galanis, Lynda J. Thomson, Geoffrey O. Ouma, Eugene Viscusi, Jerald Z. Gong, Edwin Lam

Department of Medicine Faculty Papers

Background

Apixaban pharmacokinetic properties and some clinical reports suggest cessation 48 hours prior to surgery is safe, but this has not been demonstrated in a naturalistic setting. We sought to measure the residual apixaban exposure in patients who had apixaban held as part of standard of care peri-operative management.

Methods

This was a prospective, observational study of patients in whom apixaban plasma concentration and anti-Xa activity were measured while at steady state apixaban dosing and again immediately prior to surgery. Clinical management of cessation and resumption of apixaban was at the discretion of the treating physician.

Results

One hundred and …

Acute Exacerbations Of Progressive-Fibrosing Interstitial Lung Diseases., Martin Kolb, Benjamin Bondue, Alberto Pesci, Yasunari Miyazaki, Jin Woo Song, Nitin Y. Bhatt, John T. Huggins, Justin M. Oldham, Maria L. Padilla, Jesse Roman, Md, Shane Shapera

Department of Medicine Faculty Papers

Acute exacerbation of interstitial lung disease (ILD) is associated with a poor prognosis and high mortality. Numerous studies have documented acute exacerbation in idiopathic pulmonary fibrosis (IPF), but less is known about these events in other ILDs that may present a progressive-fibrosing phenotype. We propose defining acute exacerbation as an acute, clinically significant respiratory deterioration, typically less than 1 month in duration, together with computerised tomography imaging showing new bilateral glass opacity and/or consolidation superimposed on a background pattern consistent with fibrosing ILDs. Drawing on observations in IPF, it is suspected that epithelial injury or proliferation and autoimmunity are risk …

Stimulation Of Transforming Growth Factor-Β1-Induced Endothelial-To-Mesenchymal Transition And Tissue Fibrosis By Endothelin-1 (Et-1): A Novel Profibrotic Effect Of Et-1., Peter J. Wermuth, Zhaodong Li, Fabian A. Mendoza, Sergio A. Jimenez

Department of Medicine Faculty Papers

TGF-β-induced endothelial-to-mesenchymal transition (EndoMT) is a newly recognized source of profibrotic activated myofibroblasts and has been suggested to play a role in the pathogenesis of various fibrotic processes. Endothelin-1 (ET-1) has been implicated in the development of tissue fibrosis but its participation in TGF-β-induced EndoMT has not been studied. Here we evaluated the role of ET-1 on TGF-β1-induced EndoMT in immunopurified CD31+/CD102+ murine lung microvascular endothelial cells. The expression levels of α-smooth muscle actin (α-SMA), of relevant profibrotic genes, and of various transcription factors involved in the EndoMT process were assessed employing quantitative RT-PCR, immunofluorescence histology and Western blot analysis. …

Epidermal Growth Factor Coordinately Regulates The Expression Of Prostaglandin G/H Synthase And Cytosolic Phospholipase A2 Genes In Embryonic Mouse Cells., Kenneth P. Chepenik, Arturo Diaz, Sergio A. Jimenez

Department of Medicine Faculty Papers

Confluent, primary cultures of mouse embryo palate mesenchyme (MEPM) cells are refractory to activation of phospholipase A2 (PLA2) by the calcium ionophore A23187. However, treatment of these cultures with epidermal growth factor (EGF) permits the cells to activate PLA2 in response to A23187. We have developed this finding by exploring molecular mechanisms by which growth factors modulate mobilization and metabolism of arachidonic acid. We found chronic treatment (> 6 h) of confluent MEPM cells with EGF (a) increases their ability to metabolize exogenous arachidonic acid to prostaglandin E2 (PGE2) and (b) stimulated constitutive expression of activities of PLA2 and cyclooxygenase …