Life Sciences Commons^™

Long-Term Trends In The Use Of Coronary Reperfusion Strategies In Acute Myocardial Infarction: A Community-Wide Perspective, Robert Goldberg, Frederick Spencer, Joseph Okolo, Darleen Lessard, Jorge Yarzebski, Joel Gore

Jorge L. Yarzebski

BACKGROUND: The objectives of our study were to examine long-term (1986-2003) trends in the use of percutaneous coronary interventions (PCI) and thrombolytic therapy in the management of patients hospitalized with acute myocardial infarction (AMI) while our secondary study goal was to examine factors associated with use of these coronary reperfusion strategies. While there have been considerable changes in the management of patients hospitalized with AMI over time, limited contemporary data are available about changing trends in the use of different coronary reperfusion strategies, particularly from the more generalizable perspective of a population-based investigation. METHODS: The study sample consisted of 9,422 …

Use Of Do-Not-Resuscitate Orders In Patients With Kidney Disease Hospitalized With Acute Myocardial Infarction, Joline Chen, Jonathan Sosnov, Darleen Lessard, Jorge Yarzebski, Joel Gore, Robert Goldberg

Jorge L. Yarzebski

BACKGROUND: Patients with kidney disease are at increased risk for adverse health outcomes in comparison to patients without kidney disease. Therefore, patients with kidney disease may have greater use of do-not-resuscitate (DNR) orders than patients without kidney disease in the setting of an acute illness. We examined the association between advanced kidney disease and use of DNR orders in patients admitted with an acute myocardial infarction (AMI) to all greater Worcester, MA, hospitals as part of an epidemiological study.

METHODS: Use of DNR orders in 4,033 Worcester residents hospitalized with AMI at 11 greater Worcester medical centers during 1997, 1999, …

Treatment Practices And Outcomes Of Patients With Established Peripheral Arterial Disease Hospitalized With Acute Myocardial Infarction In A Community Setting, Frederick Spencer, Darleen Lessard, Chyke Doubeni, Jorge Yarzebski, Joel Gore, Robert Goldberg

Jorge L. Yarzebski

BACKGROUND: There are little contemporary data available describing the hospital and long-term outcomes of patients with peripheral arterial disease (PAD) who are hospitalized with acute myocardial infarction (AMI). The objectives of our population-based study were to examine the hospital and long-term outcomes, as well as the use of different treatment practices, among patients with established PAD who were hospitalized with AMI. METHODS: The study sample consisted of 4480 patients hospitalized with AMI at all Worcester, Mass, medical centers in 4 alternate years between 1997 and 2003. RESULTS: Among the metropolitan Worcester residents hospitalized with AMI, 13.5% had a history of …

Communities Of Cloacal Bacteria In Tree Swallow Families, Michael Lombardo, Patrick Thorpe, R. Cichewicz, M. Henshaw, C. Millard, C. Steen, T. Zeller

Michael P Lombardo

Our aim in this study was to survey the communities of bacteria found in the cloacae of adult and nestling Tree Swallows (Tachycineta bicolor), determine if there were familial patterns of prevalence, and determine if there were relationships between bacteria loads and nestling size when 12 days old and fledging success.

Diabetic Rates And Mice Are Resistent To Porcine And Human Insulin: Flawed Experimental Models For Testing Islet Xenograft, A. Pepper, C. Gall, D. Mazzuca, C.W.J. Melling, D. White

Jamie Melling

BACKGROUND: Islet transplantation is potentially a promising therapy for the restoration of carbohydrate control to diabetic patients. However, the global application of islet transplantation requires a ubiquitous source of beta cells. The xenotransplantation of porcine islets would provide such a source. Success in porcine islet xenografting has been achieved in diabetic primates. However, there are few reports of reversal of diabetes with porcine islet xenografts in rodent models of diabetes, relative to the number of successful rodent experiments performed as allografts. Here we report for the first time the inability of porcine (and human) insulin to control blood glucose levels …

Myocardial Hsp70 Phosphorylation And Pkc-Mediated Cardioprotection Following Exercise, C.W. Melling, David Thorp, Kevin Milne, Earl Noble

Jamie Melling

Both protein kinase C (PKC) activation and Hsp70 expression have been shown to be key components for exercise-mediated myocardial protection during ischemia–reperfusion injury. Given that Hsp70 has been shown to undergo inducible phosphorylation in striated muscle and liver, we hypothesized that PKC may regulate myocardial Hsp70 function and subsequent exercise-conferred cardioprotection through this phosphorylation. Hence, acute exercise of male Sprague–Dawley rats (30 m/min for 60 min at 2% grade) was employed to assess the role of PKC and its selected isoforms in phosphorylation of Hsp70 and protection of the myocardium during ischemia-reperfusion injury. It was observed that administration of the …

Invited Review: Heat Shock Proteins And Exercise: A Primer, Earl Noble, Kevin Milne, C.W. Melling

Jamie Melling

Heat shock proteins (HSPs) are, in general, prosurvival molecules within the cellular environment, and the overexpression of even just 1 family of HSPs can lead to protection against and improvements after a variety of stressors. Not surprisingly, a fertile area of study has grown out of effors to exploit the innate biologic behaviour of HSPs. Exercise, because of the inherent physiologic stresses associated with it, is but 1 stimulus that can result in a robust increase in various HSPs in several tissues, not the least of which happen to be the heart and skeletal muscle. The purpose of this review …

Exercise-Mediated Regulation Of Hsp70 Gene Expression Following Exercise Training, C.W. Melling, David Thorp, Kevin Milne, Matthew Krause, Earl Noble

Jamie Melling

An issue central to understanding the biological benefits associated with regular exercise training is to elucidate the intracellular mechanisms governing exercise-conferred cardioprotection. Heat shock proteins (HSPs), most notably the inducible 70-kDa HSP family member Hsp70, are believed to participate in the protection of the myocardium during cardiovascular stress. Following acute exercise, activation of PKA mediates the suppression of an intermediary protein kinase, ERK1/2, which phosphorylates and suppresses the activation of the heat shock transcription factor 1 (HSF1). However, following exercise training, ERK1/2 has been reported to regulate the transcriptional activation of several genes involved in cell growth and proliferation and …

Pka-Mediated Erk1/2 Inactivation And Hsp70 Gene Expression Following Exercise, C.W. Melling, Matthew Krause, Earl Noble

Jamie Melling

Exercise induces the expression of the cardioprotective protein, Hsp70, through the activation of its transcription factor HSF1. Recently, we reported that administration of a protein kinase A (PKA) inhibitor suppressed exercise-induced hsp70 gene expression, suggesting a role for PKA in the regulation of HSF1 activation in vivo. While the mechanism by which PKA regulates HSF1 is unclear, studies in vitro have reported that HSF1 is phosphorylated on two serine residues by mitogen activated protein kinases (MAPKs); ERK1/2 (ser307) and JNK/SAPK (ser363). As PKA is a regulator of these protein kinases, the current study examined the role of PKA in their …

Castration Inhibits The Exercise-Induced Accumulation Of Hsp70 In Male Rodent Cardiac Muscle Tissue, Kevin Milne, David Thorp, C.W. Melling, Earl Noble

Jamie Melling

Intense exercise leads to accumulation of the inducible member of the 70-kDa family of heat shock proteins, Hsp70, in male, but not female, hearts. Estrogen is at least partially responsible for this difference. Because androgen receptors are expressed in the heart and castration leads to decreases in calcium regulatory proteins and altered cardiac function, testosterone (T) or its metabolites could also be involved. We hypothesized that removal of endogenous T production through castration would reduce cardiac Hsp70 accumulation after an acute exercise bout, whereas castrated animals supplemented with 5α-dihydrotestosterone (DHT) would show the intact male response. Fifty-four 8-wk-old male Sprague-Dawley …