Medicine and Health Sciences Commons^™

Effect Of Flecainide And Ibutilide Alone And In Combination To Terminate And Prevent Recurrence Of Atrial Fibrillation, Alexander Burashnikov, José M. Di Diego, Bence Patocskai, Debra S. Echt, Luiz Belardinelli, Charles Antzelevitch

Division of Cardiology Faculty Papers

BACKGROUND: There is a need for improved approaches to rhythm control therapy of atrial fibrillation (AF).

METHODS: The effectiveness of flecainide (1.5 µmol/L) and ibutilide (20 nmol/L), alone and in combination, to cardiovert and prevent AF recurrence was studied in canine-isolated coronary-perfused right atrioventricular preparations. We also examined the safety of the combination of flecainide (1.5 µmol/L) and ibutilide (50 nmol/L) using canine left ventricular wedge preparations.

RESULTS: Sustained AF (>1 hour) was inducible in 100%, 60%, 20%, and 0% of atria in the presence of acetylcholine alone, acetylcholine+ibutilide, acetylcholine+flecainide, and acetylcholine+ibutilide+flecainide, respectively. When used alone, flecainide and ibutilide …

Nerve Transfer For Restoration Of Lower Motor Neuron-Lesioned Bladder, Urethral, And Anal Sphincter Function In A Dog Model. Part 3. Nicotinic Receptor Characterization, Nagat Frara, Mary F. Barbe, Dania Giaddui, Danielle S. Porreca, Alan S. Braverman, Ekta Tiwari, Attia Ahmad, Justin M. Brown, Benjamin R. Johnston, Stanley F. Bazarek, Michael R. Ruggieri

Department of Neurology Faculty Papers

Very little is known about the physiological role of nicotinic receptors in canine bladders, although functional nicotinic receptors have been reported in bladders of many species. Utilizing in vitro methods, we evaluated nicotinic receptors mediating bladder function in dogs: control (9 female and 11 male normal controls, 5 sham operated), Decentralized (9 females, decentralized 6–21 mo), and obturator-to-pelvic nerve transfer reinnervated (ObNT-Reinn; 9 females; decentralized 9–13 mo, then reinnervated with 8–12 mo recovery). Muscle strips were collected, mucosa-denuded, and mounted in muscle baths before incubation with neurotransmitter antagonists, and contractions to the nicotinic receptor agonist epibatidine were determined. Strip response …

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 …

A Rodent Model For Dirofilaria Immitis, Canine Heartworm: Parasite Growth, Development, And Drug Sensitivity In Nsg Mice, Jessica A. Hess, Mark L. Eberhard, Marcelo Segura-Lepe, Kathrin Grundner-Culemann, Barbara Kracher, Jeffrey Shryock, John Harrington, David Abraham

Department of Microbiology and Immunology Faculty Papers

Heartworm disease, caused by Dirofilaria immitis, remains a significant threat to canines and felines. The development of parasites resistant to macrocyclic lactones (ML) has created a significant challenge to the control of the infection. The goal of this study was to determine if mice lacking a functional immune response would be susceptible to D. immitis. Immunodeficient NSG mice were susceptible to the infection, sustaining parasites for at least 15 weeks, with infective third-stage larvae molting and developing into the late fourth-stage larvae. Proteomic analysis of host responses to the infection revealed a complex pattern of changes after infection, with at …

Effect Of Pulse Shaping On Subharmonic Aided Pressure Estimation In Vitro And In Vivo., Ipshita Gupta, John R. Eisenbrey, Maria Stanczak, Anush Sridharan, Jaydev K. Dave, Ji-Bin Liu, Christopher Hazard, Xinghua Wang, Ping Wang, Huiwen Li, Kirk Wallace, Flemming Forsberg

Department of Radiology Faculty Papers

OBJECTIVES: Subharmonic imaging (SHI) is a technique that uses the nonlinear oscillations of microbubbles when exposed to ultrasound at high pressures transmitting at the fundamental frequency ie, f

METHODS: Eight waveforms with different envelopes were optimized with respect to acoustic power at which the SHAPE study is most sensitive. The study was run with four input transmit cycles, first in vitro and then in vivo in three canines to select the waveform that achieved the best sensitivity for detecting changes in portal pressures using SHAPE. A Logiq 9 scanner with a 4C curvi-linear array was used to acquire 2.5 MHz …

Intravenous Inoculation Of A Bat-Associated Rabies Virus Causes Lethal Encephalopathy In Mice Through Invasion Of The Brain Via Neurosecretory Hypothalamic Fibers., Mirjam A R Preuss, Marie-Luise Faber, Gene S Tan, Michael Bette, Bernhard Dietzschold, Eberhard Weihe, Matthias J Schnell

Department of Microbiology and Immunology Faculty Papers

The majority of rabies virus (RV) infections are caused by bites or scratches from rabid carnivores or bats. Usually, RV utilizes the retrograde transport within the neuronal network to spread from the infection site to the central nervous system (CNS) where it replicates in neuronal somata and infects other neurons via trans-synaptic spread. We speculate that in addition to the neuronal transport of the virus, hematogenous spread from the site of infection directly to the brain after accidental spill over into the vascular system might represent an alternative way for RV to invade the CNS. So far, it is unknown …

Animal Bite Infections., Joel D. Klein, Md

Department of Pediatrics Faculty Papers

Animal bites have become alarmingly common and may represent a quiet epidemic. It is estimated that between 1 and 3.5 million animal bites occur annually in the United States. The highest incidence has consistently been in 5-to-14-year-old schoolchildren, who have greater contact with animals, especially house pets, on a daily basis. This article discusses the epidemiology, microbiology, clinical findings and management of animal bites infections.