Medicine and Health Sciences Commons^™

Adiponectin Inhibits Oxidative/Nitrative Stress During Myocardial Ischemia And Reperfusion Via Pka Signaling., Yanqing Zhang, Xiao-Liang Wang, Jianli Zhao, Ya-Jing Wang, Wayne Bond Lau, Yue-Xing Yuan, Er-He Gao, Walter J. Koch, Xin-Liang Ma

Department of Emergency Medicine Faculty Papers

The cardioprotective effects of adiponectin (APN) against myocardial ischemia/reperfusion (MI/R) injury are well known. However, comprehension of the mechanisms mediating intracellular APN signaling remains incomplete. We recently demonstrate the antioxidant/antinitrative effects of APN are not dependent on AMPK. Protein kinase A (PKA) has been previously shown to be activated by APN, with uncertain relevance to APN cardiac protection. The current study determined whether the antioxidative/antinitrative effect of APN is mediated by PKA. Administration of APN (2 μg/g) 10 min before reperfusion significantly enhanced cardiac PKA activity, reduced oxidative stress, and decreased infarct size. Knockdown of cardiac PKA expression (PKA-KD) by …

Thioredoxin Reductase Was Nitrated In The Aging Heart After Myocardial Ischemia/Reperfusion., Ke Wang, Jie Zhang, Xiaoliang Wang, Xin Liu, Lin Zuo, Kehua Bai, Jianyu Shang, Lu Ma, Teng Liu, Li Wang, Wen Wang, Xin-Liang Ma, Huirong Liu

Department of Emergency Medicine Faculty Papers

The age-related loss of anti-oxidant defense reduces recovery from myocardial ischemia/reperfusion injury (MI/R) in aged people. Our previous data showed that inactivation of thioredoxin (Trx) was involved in enhanced aging MI/R injury. Thioredoxin reductase (TrxR), the enzyme known to regulate Trx, is less efficient with age. The aim of the current study was to determine why TrxR activity was reduced and whether reduced TrxR activity contributed to enhanced aging MI/R injury. Both Trx and TrxR activity were decreased in the aging heart, and this difference was further amplified after MI/R. However, MI/R injury did not change TrxR expression between young …

Inhibition Of Fas-Associated Death Domain-Containing Protein (Fadd) Protects Against Myocardial Ischemia/Reperfusion Injury In A Heart Failure Mouse Model., Qian Fan, Zheng M Huang, Matthieu Boucher, Xiying Shang, Lin Zuo, Henriette Brinks, Wayne Bond Lau, Jianke Zhang, J Kurt Chuprun, Erhe Gao

Department of Emergency Medicine Faculty Papers

AIM: As technological interventions treating acute myocardial infarction (MI) improve, post-ischemic heart failure increasingly threatens patient health. The aim of the current study was to test whether FADD could be a potential target of gene therapy in the treatment of heart failure.

METHODS: Cardiomyocyte-specific FADD knockout mice along with non-transgenic littermates (NLC) were subjected to 30 minutes myocardial ischemia followed by 7 days of reperfusion or 6 weeks of permanent myocardial ischemia via the ligation of left main descending coronary artery. Cardiac function were evaluated by echocardiography and left ventricular (LV) catheterization and cardiomyocyte death was measured by Evans blue-TTC …

Creg Promotes The Proliferation Of Human Umbilical Vein Endothelial Cells Through The Erk/Cyclin E Signaling Pathway., Jie Tao, Chenghui Yan, Xiaoxiang Tian, Shaowei Liu, Yang Li, Jian Zhang, Mingyu Sun, Xinliang Ma, Yaling Han

Department of Emergency Medicine Faculty Papers

Cellular repressor of E1A-stimulated genes (CREG) is a recently discovered secreted glycoprotein involved in homeostatic modulation. We previously reported that CREG is abundantly expressed in the adult vascular endothelium and dramatically downregulated in atherosclerotic lesions. In addition, CREG participates in the regulation of apoptosis, inflammation and wound healing of vascular endothelial cells. In the present study, we attempted to investigate the effect of CREG on the proliferation of vascular endothelial cells and to decipher the underlying molecular mechanisms. Overexpression of CREG in human umbilical vein endothelial cells (HUVEC) was obtained by infection with adenovirus carrying CREG. HUVEC proliferation was investigated …

Intermedin Protects Against Myocardial Ischemia-Reperfusion Injury In Diabetic Rats., Hong Li, Yunfei Bian, Nana Zhang, Jia Guo, Cheng Wang, Wayne Bond Lau, Chuanshi Xiao

Department of Emergency Medicine Faculty Papers

BACKGROUND: Diabetic patients, through incompletely understood mechanisms, endure exacerbated ischemic heart injury compared to non-diabetic patients. Intermedin (IMD) is a novel calcitonin gene-related peptide (CGRP) superfamily member with established cardiovascular protective effects. However, whether IMD protects against diabetic myocardial ischemia/reperfusion (MI/R) injury is unknown. METHODS: Diabetes was induced by streptozotocin in Sprague--Dawley rats. Animals were subjected to MI via left circumflex artery ligation for 30 minutes followed by 2 hours R. IMD was administered formally 10 minutes before R. Outcome measures included left ventricular function, oxidative stress, cellular death, infarct size, and inflammation. RESULTS: IMD levels were significantly decreased in …

Increased Expression Of Pigment Epithelium-Derived Factor In Aged Mesenchymal Stem Cells Impairs Their Therapeutic Efficacy For Attenuating Myocardial Infarction Injury., Hongliang Liang, Huiyuan Hou, Wei Yi, Guodong Yang, Chunhu Gu, Wayne Bond Lau, Erhe Gao, Xinliang Ma, Zifan Lu, Xufeng Wei, Jianming Pei, Dinghua Yi

Department of Emergency Medicine Faculty Papers

AIMS: Mesenchymal stem cells (MSCs) can ameliorate myocardial infarction (MI) injury. However, older-donor MSCs seem less efficacious than those from younger donors, and the contributing underlying mechanisms remain unknown. Here, we determine how age-related expression of pigment epithelium-derived factor (PEDF) affects MSC therapeutic efficacy for MI.

METHODS AND RESULTS: Reverse transcriptase-polymerized chain reaction and enzyme-linked immunosorbent assay analyses revealed dramatically increased PEDF expression in MSCs from old mice compared to young mice. Morphological and functional experiments demonstrated significantly impaired old MSC therapeutic efficacy compared with young MSCs in treatment of mice subjected to MI. Immunofluorescent staining demonstrated that administration of …

Lymphotoxin-Α Is A Novel Adiponectin Expression Suppressor Following Myocardial Ischemia/Reperfusion., Wayne Bond Lau, Yanqing Zhang, Jianli Zhao, Baojiang Liu, Xiaoliang Wang, Yuexing Yuan, Theodore A. Christopher, Bernard Lopez, Erhe Gao, Walter J. Koch, Xin L. Ma, Yajing Wang

Department of Emergency Medicine Faculty Papers

Recent clinical observations demonstrate adiponectin (APN), an adipocytokine with potent cardioprotective actions, is significantly reduced following myocardial ischemia/reperfusion (MI/R). However, mechanisms responsible for MI/R-induced hypoadiponectinemia remain incompletely understood. Adult male mice were subjected to 30-min MI followed by varying reperfusion periods. Adipocyte APN mRNA and protein expression and plasma APN and TNFα concentrations were determined. APN expression/production began to decline 3 h after reperfusion (reaching nadir 12 h after reperfusion), returning to control levels 7 days after reperfusion. Plasma TNFα levels began to increase 1 h after reperfusion, peaking at 3 h and returning to control levels 24 h after …

Clinician-Performed Beside Ultrasound For The Diagnosis Of Traumatic Pneumothorax., Bon S. Ku, Jason M. Fields, Brendan Carr, Worth W Everett, Vincent H Gracias, Anthony J Dean

Department of Emergency Medicine Faculty Papers

INTRODUCTION: Prior studies have reported conflicting results regarding the utility of ultrasound in the diagnosis of traumatic pneumothorax (PTX) because they have used sonologists with extensive experience. This study evaluates the characteristics of ultrasound for PTX for a large cohort of trauma and emergency physicians.

METHODS: This was a prospective, observational study on a convenience sample of patients presenting to a trauma center who had a thoracic ultrasound (TUS) evaluation for PTX performed after the Focused Assessment with Sonography for Trauma exam. Sonologists recorded their findings prior to any other diagnostic studies. The results of TUS were compared to one …

Ginsenoside Rd Attenuates Myocardial Ischemia/Reperfusion Injury Via Akt/Gsk-3Β Signaling And Inhibition Of The Mitochondria-Dependent Apoptotic Pathway., Yang Wang, Xu Li, Xiaoliang Wang, Wayne Bond Lau, Yajing Wang, Yuan Xing, Xing Zhang, Xinliang Ma, Feng Gao

Department of Emergency Medicine Faculty Papers

Evidence suggests Ginsenoside Rd (GSRd), a biologically active extract from the medical plant Panax Ginseng, exerts antioxidant effect, decreasing reactive oxygen species (ROS) formation. Current study determined the effect of GSRd on myocardial ischemia/reperfusion (MI/R) injury (a pathological condition where ROS production is significantly increased) and investigated the underlying mechanisms. The current study utilized an in vivo rat model of MI/R injury and an in vitro neonatal rat cardiomyocyte (NRC) model of simulated ischemia/reperfusion (SI/R) injury. Infarct size was measured by Evans blue/TTC double staining. NRC injury was determined by MTT and lactate dehydrogenase (LDH) leakage assay. ROS accumulation and …

Aortic Dissection Presenting As Gait Disturbance: A Case Report., Michael Estreicher, Joseph Portale, Bernard Lopez

Department of Emergency Medicine Faculty Papers

Emergency medicine dogma traditionally teaches that aortic dissection presents as tearing chest pain, radiating to the back. This case report describes a 55 year old woman presenting with a left homonymous hemianopsia and resultant gait disturbance. Initial head CT demonstrated a right parietal infarct, and chest radiograph demonstrated a markedly widened mediastinum. Acute Stanford Type A aortic dissection was subsequently confirmed. This report provides further evidence for atypical, painless presentations of aortic dissection. Given recent literature on the increasing prevalence of painless dissection, the disease entity should be included in the differential diagnosis for stroke, and a simple portable chest …

Tumor Necrosis Factor-Α And Lymphotoxin-Α Mediate Myocardial Ischemic Injury Via Tnf Receptor 1, But Are Cardioprotective When Activating Tnf Receptor 2., Yanqing Zhang, Jianli Zhao, Wayne Bond Lau, Li-Yuan Jiao, Baojiang Liu, Yuexing Yuan, Xiaoliang Wang, Erhe Gao, Walter J Koch, Xin-Liang Ma, Yajing Wang

Department of Emergency Medicine Faculty Papers

OBJECTIVE: This study determines the roles of tumor necrosis factor-α (TNFα) and lymphotoxin-α (LTα) in post-myocardial infarction (post-MI) cardiac injury, and identifies the TNF receptor type responsible for TNFα- and LTα-mediated cardiac injury.

METHODS AND RESULTS: Adult male wild type (WT), TNFα(-/-), LTα(-/-), TNFR1(-/-), and TNFR2(-/-) mice were subjected to MI via coronary artery occlusion. Functional, histological, and biochemical analyses were performed 1 to 7 days post-MI. In WT mice, MI significantly increased both TNFα and LTα levels in plasma, but in distinct temporal manner. Plasma TNFα peaked 1 day after MI, and decreased toward baseline 3 days after MI. …

Rewarming For Accidental Hypothermia In An Urban Medical Center Using Extracorporeal Membrane Oxygenation., David Morley, Kentaro Yamane, Rika O'Malley, Nicholas Cavarocchi, Hitoshi Hirose

Department of Emergency Medicine Faculty Papers

BACKGROUND: Accidental hypothermia complicated by cardiac arrest carries a high mortality rate in urban areas. For moderate hypothermia cases conventional rewarming methods are usually adequate, however in severe cases extracorporeal membrane oxygenation (ECMO) is known to provide the most efficient rewarming with complete cardiopulmonary support. We report a case of severe hypothermia complicated by prolonged cardiac arrest successfully resuscitated using ECMO.

CASE REPORT: A 45 year old female was brought to our emergency department with a core body temperature

CONCLUSIONS: This case demonstrates the advantages of advanced internal rewarming techniques, such as ECMO, for quick and efficient rewarming of severely …