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Results 251 - 300 of 725
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Sheps David S - - 2002
BACKGROUND: Ischemia during laboratory mental stress tests has been linked to significantly higher rates of adverse cardiac events. Previous studies have not been designed to detect differences in mortality rates. METHODS AND RESULTS: To determine whether mental stress-induced ischemia predicts death, we evaluated 196 patients from the Psychophysiological Investigations of ...
Celik Husnu - - 2002
OBJECTIVES: Pulmonary edema has been shown to occur following ischemia-reperfusion injury in a variety of organs and effects of several pharmacological agents on ischemia-reperfusion-induced damage has been investigated previously. However, there are only a few studies in the literature about pulmonary injury following adnexial ischemia-reperfusion. In this study we aimed ...
Prasan Ananth M - - 2002
Effects of ischemia time and treatment interventions upon troponin I (TnI) proteolysis and function of reperfused myocardium were examined in isolated, perfused rabbit hearts. Hearts were randomized to 90 min aerobic perfusion, 15 min low-flow (1 ml/min) ischemia (I) and 60 min reperfusion (R) or 60 min low-flow I and ...
Babai László - - 2002
Dogs were subjected to exercise on a treadmill, using a protocol in which the speed and slope were increased every 3 min, and which elevated both heart rate (to a mean of 198+/-14 beats.min(-1)) and mean arterial blood pressure (to 150+/-4 mmHg). Then, 24 or 48 h later, the dogs ...
Benz Stefan - - 2002
In ischemia/reperfusion of the pancreas impairment of microcirculation after reperfusion is believed to be of critical importance. The 'no-reflow' phenomenon is thought to cause persisting tissue ischemia, while the 'reflow-paradox' is defined as secondary impairment of nutritive perfusion. These phenomena have been shown by intravital microscopy but their effect on ...
Haunstetter Armin - - 2002
It was the aim of the present study to characterize the effect of single components of ischaemia, such as inhibition of aerobic and anaerobic energy production by combined anoxic and glucose-free perfusion (metabolic inhibition), high extracellular potassium concentrations (hyperkalaemia), and acidosis, on (1). the stimulated release of noradrenaline from the ...
Crestanello Juan A - - 2002
Background. Ischemic preconditioning (IPC) protects the myocardium from ischemia reperfusion injury. The effect of IPC on the mitochondria is not well known. However, one of the mechanisms postulated in IPC (the opening of the mitochondrial K(ATP) channels) is likely to result in changes in mitochondrial function. Therefore, the purpose of ...
Messina Louis M - - 2002
Lower extremity arterial occlusive disease results in tissue ischemia of the legs and is relatively common in the elderly. Clinically, it may be asymptomatic, cause muscle pain during exercise, or progress to a severe degree of ischemia that may result in limb loss. Although bypass surgery and angioplasty have increased ...
Pozzi Silvia - - 2002
Post-ischemic reperfusion leads to apoptosis-linked loss of myocytes in cultured cells and in vivo. We tested the hypothesis that apoptosis develops without reperfusion in Langendorff-perfused hearts exposed to either low-flow ischemia (LFI) or hypoxia (H). Rat hearts were perfused with amino-acid-enriched Krebs-Henseleit buffer and exposed for 6 h to LFI ...
Porcu Paolo - - 2002
BACKGROUND: Tissue kallikrein (tK) and vascular endothelial growth factor (VEGF) are potent angiogenic agents. Upregulation of tK or VEGF was documented in animal models of acute ischemia, yet it remains unknown whether these endothelial cell mitogens are overexpressed in chronic peripheral vascular insufficiency. METHODS AND RESULTS: Circulating tK and VEGF ...
Asgari S - - 2002
OBJECTIVES: Near-infrared spectroscopy (NIRS) based technology allows in-vivo monitoring of focal tissue cytochrome aa3 (cytochrome-c-oxidase). The aim of this study was to assess early cell alteration during acute focal cerebral ischaemia and reperfusion. METHODS: Focal cerebral ischaemia was induced in 12 rats using an endovascular occlusion technique of the middle ...
Weinbroum A A - - 2002
We had previously studied different modes of prevention of liver ischemia-reperfusion (IR)-induced remote organ reperfusion injury, a challenge that remains partly unmet. We have now studied the capability of mannitol at different doses in abrogating liver IR-induced lung reperfusion injury in an isolated double-organ model. Rat livers ( n = ...
Negroni Jorge A - - 2002
OBJECTIVE: Although late preconditioning protects against stunning following several short periods of ischemia-reperfusion, it is not clear if it confers protection against stunning and malignant arrhythmias after a sustained reversible ischemia, and whether KATP channels are involved as triggers and/or end effectors of the protective mechanism. The purpose of this ...
Lohuis P J - - 2001
We hypothesized that arginine-vasopressin (AVP), the natural vasopressin in the guinea pig, might increase the cochlear summating potential, indicating an increase in endolymphatic volume. Guinea pig cochleas were perfused with artificial perilymph for 15 min, with or without AVP (2 x 10(-6) M). In 1 group of animals, summating potentials ...
Monnet X - - 2001
We investigated the effects of the selective bradycardic agent ivabradine, an I(f) channel inhibitor, on exercise-induced ischemia and resulting myocardial stunning. Seven dogs were chronically instrumented to measure left ventricular (LV) wall thickening (Wth), aortic pressure and coronary blood flow (CBFv) (Doppler). Circumflex coronary artery stenosis was set up to ...
Grosse-Siestrup C - - 2001
INTRODUCTION: Current models of isolated and perfused livers are limited by nonphysiologic perfusates or the need for the use of high numbers of laboratory animals. The present study was performed in order to rectify these difficulties. METHODS: To establish a new isolated perfused liver model, a perfusion circuit was developed ...
Vergely C - - 2001
Free radicals produced during myocardial post-ischemic reperfusion are aggravating factors for functional disturbances and cellular injury. The aim of our work was to investigate the significance of the secondary free radical release during non ischemic perfusion and post-ischemic reperfusion and to evaluate the cardiovascular effects of the spin trap used. ...
Demirel H A - - 2001
These experiments examined the independent effects of short-term exercise and heat stress on myocardial responses during in vivo ischemia-reperfusion (I/R). Female Sprague-Dawley rats (4 mo old) were randomly assigned to one of four experimental groups: 1) control, 2) 3 consecutive days of treadmill exercise [60 min/day at 60-70% maximal O2 ...
Wikström G - - 2001
During pre-conditioning the interstitial concentration of adenosine, in contrast to lactate, presents a die-away curve-pattern for every successive episode of ischaemia. This die-away pattern might not necessarily be attributed to diminished adenosine production. The present study was undertaken to investigate whether pre-conditioning alters the metabolic turnover of adenosine as observed ...
Pajdo R - - 2001
Various organs, including heart, kidneys, liver or brain, respond to brief exposures to ischemia with an increased resistance to severe ischemia/reperfusion and this phenomenon is called "preconditioning". No study so far has been undertaken to check whether such short, repeated gastric ischemic episodes protect gastric mucosa against severe damage caused ...
Wagner F M - - 2001
The direct visualization of systemic microcirculation using intravitalmicroscopy permits the classification of proinflammatory and ischemic microvascular alterations during normothermic and hypothermic cardiopulmonary bypass in neonates. We used seven newborn piglets, on average aged 9 days, and weighing 3200g, as a control group. In addition, we studied nine piglets subjected to ...
Jennings R B - - 2001
Ischemic preconditioning is associated with slower destruction of the adenine nucleotide pool and a slower rate of anaerobic glycolysis during subsequent ischemic stress. Whether this association is causal is uncertain. Using metabolite levels found at baseline and after a 15 min test episode of ischemia, this study tested for concordance, ...
Araujo E G - - 2001
BACKGROUND: Because cardiopulmonary bypass (CPB) is associated with edema and vasoreactive dysfunction and ERK1/2 pathway is involved in vascular contractility and permeability, a time course study was performed to monitor MEK/ERK1/2/Elk-1 activities during CPB. METHODS: Pigs were subjected to normothermic CPB for 90 minutes followed by post-CPB perfusion for 180 ...
Otte J A - - 2001
Heavy physical exercise may cause gastrointestinal signs and symptoms, and, although splanchnic blood flow may decrease through redistribution by more than 50%, it is unclear whether these signs and symptoms relate to gastrointestinal ischemia. In 10 healthy volunteers, we studied the effect of exercise on gastric mucosal perfusion adequacy using ...
Tabuchi K - - 2001
To examine whether an active process of the cochlea was injured by ischemia-reperfusion, time courses of distortion-product otoacoustic emissions (DPOAEs) were examined before, during and after 30 min cochlear ischemia using albino guinea pigs. DPOAEs decreased to the minimum level when the animals were subjected to ischemia. When the cochlea ...
Sair M - - 2001
OBJECTIVE: Multiple organ dysfunction is associated with systemic sepsis. To investigate whether this is attributable to peripheral tissue hypoperfusion and/or cellular hypoxia, simultaneous measurements of tissue perfusion and oxygenation were made in patients with severe sepsis and in controls. DESIGN: Prospective, observational study. SETTING: Adult intensive care unit, tertiary referral ...
Kawabata H - - 2001
Although angiotensin converting enzyme (ACE) inhibitor and/or angiotensin II type 1 (AT1) receptor antagonist can protect the myocardium against ischemia-reperfusion injury, the mechanisms of the effect have not yet been characterized at the cellular level. We here examined the effect of the combination of an ACE inhibitor, temocaprilat, an AT1 ...
Hoffmann S C - - 2001
Studies suggest that pulmonary vascular ischemia-reperfusion injury (IRI) can be attenuated by increasing intracellular cAMP concentrations. The purpose of this study was to determine the effect of IRI on capillary permeability, assessed by capillary filtration coeficient (Kfc), in lungs retrieved from non-heart-beating donors (NHBDs) and reperfused with the addition of ...
Lubov T - - 2001
Elevated endothelin-1 levels were found in exercise-induced ischemia. To our knowledge, no attempt has been made to correlate the presence of the elevated endothelin levels with severity of ischemia. In the present study, we attempt to correlate the severity of ischemia, quantified using a bullseye visual display of scintigraphic ischemic ...
Nandagopal K - - 2001
Preconditioning to ischemic tolerance is a phenomenon in which brief episodes of a subtoxic insult induce a robust protection against the deleterious effects of subsequent, prolonged, lethal ischemia. The subtoxic stimuli that constitute the preconditioning event are quite diverse, ranging from brief ischemic episodes, spreading depression or potassium depolarization, chemical ...
Moneley D - - 2001
BACKGROUND: Respiratory complications continue to be a major cause of morbidity and mortality following major vascular surgery. The recent UK Small Aneurysm Trial cited preoperative respiratory function as the major predictor of outcome following elective aortic surgery. AIM: The aim of this study was to investigate the effect of aortic ...
Kim W G - - 2001
An experiment to study the role of contact-activation leukocyte sequestration in the formation of ischaemia-reperfusion injury (I-R injury) was carried out. The study was conducted using light and electron microscopic analyses in an ovine cardiopulmonary bypass (CPB) model using a membrane oxygenator. Five adult sheep were used in the study. ...
Seligmann C - - 2001
Polymorphonuclear granulocytes (PMNs) are known to contribute to reperfusion injury of the heart. However, whether PMNs compromise myocardial function of hearts exposed to a low-flow ischemia has not been determined. Moreover, not much is known about deleterious effects of PMNs at different times during ischemia and reperfusion. Isolated, working guinea ...
Schlag M G - - 2001
The role of leukocytes and nonleukocyte-derived reactive oxygen metabolites (ROMs) in reperfusion-induced skeletal muscle injury was determined. Male rats received 2 h no-flow hindlimb ischemia-reperfusion (I/R, n = 6) or were rendered neutropenic via antineutrophil serum (ANS) before I/R (I/R + ANS, n = 5). Oxygen radicals in the absence ...
Cornelussen R N - - 2001
We investigated whether the cardioprotection induced by heat stress (HS) pretreatment is associated with mitigation of phospholipid degradation during the ischemic and/or postischemic period. The hearts, isolated from control rats and from heat-pretreated rats (42 degrees C for 15 min) either 30 min (HS0.5-h) or 24 h (HS24-h) earlier, were ...
Midorikawa J - - 2001
To investigate the time course of superoxide generation in ischemia-reperfusion in the in-vivo rat lung, the present study used an enhanced chemiluminescence method with 2-methyl-6-[p-methoxyphenyl]-3,7-dihydroimidazo[1, 2-alpha]pyrazin-3-one (MCLA) as a specific probe. The right pulmonary artery was occluded for 120 min, followed by 90-min reperfusion. Chemiluminescence induced by MCLA was continuously ...
Tabuchi K - - 2001
We investigated the effect of a hydroxyl radical scavenger, 1,3-dimethyl-2-thiourea (dimethylthiourea), and two xanthine oxidase inhibitors, oxypurinol and allopurinol, on the threshold shift of the compound action potential (CAP) after transient ischemia of the cochlea. Transient ischemia of 30 min duration was induced in albino guinea pigs via a skull ...
Costa F - - 2001
There is substantial evidence that adenosine activates muscle afferent nerve fibers leading to sympathetic stimulation, but the issue remains controversial. To further test this hypothesis, we used local injections of adenosine into the brachial artery while monitoring systemic muscle sympathetic nerve activity (MSNA) with peroneal microneurography. The increase in MSNA ...
Powers S K - - 2001
Heat shock proteins (HSPs) play a critical role in maintaining cellular homeostasis and protecting cells during episodes of acute stress. Specifically, HSPs of the 70 kDa family (i.e., HSP72) are important in preventing ischemia-reperfusion induced apoptosis, necrosis, and oxidative injury in a variety of cell types including the cardiac myocyte. ...
Toufektsian M C - - 2001
Oxygen-derived free radicals (O2.-, H2O2, and .OH) that are produced during postischemic reperfusion are currently suspected to be involved in the pathogenesis of tissue injury. Another reactive oxygen species, the electronically excited molecular oxygen (1O2), is of increasing interest in the area of experimental research in cardiology. In this review ...
Heindl B - - 2001
Inhibition of cyclooxygenase (COX) might favour non-enzymatic formation of cardiodepressive isoprostanes from arachidonic acid by radicals generated during reperfusion. This could explain deleterious effects of acetylsalicylic acid (ASA) on cardiac function. We examined the influence of COX inhibition on myocardial function after low-flow ischaemia and reperfusion, employing either ASA (100 ...
Bozkurt M F - - 2001
Exercise-induced left bundle branch block (Ex-LBBB) is a rare entity encountered during exercise testing. The authors present a 53-year-old woman who developed intermittent Ex-LBBB asymptomatically during Tl 201 myocardial perfusion scintigraphy. Scintigraphic findings revealed septal-anteroseptal ischemia while the coronary arteriogram appeared normal. False-positive septal-anteroseptal scintigraphic findings suggesting ischemia in patients ...
Yenari M A - - 2001
Microglia are known to secrete neurotoxic substances and have been implicated in potentiating injury in a variety of neuropathological settings including stroke. However, little is known about the susceptibility of microglia to ischemia. Here we characterize microglial vulnerabilities to ischemia-like insults. Microglia were remarkably resistant to hypoxia, but a majority ...
Broderick T L - - 2001
Clinical and experimental data suggest that exercise training (ET) and food restriction (FR) improve cardiovascular function. However, the effects of long-term FR or FR in combination with ET on the recovery of cardiac function following ischemia have not been determined. Male Wistar rats were assigned to ad libitum-fed, FR, ad ...
De Curzon O P - - 2001
Late preconditioning (PC) against myocardial stunning develops after coronary artery occlusion (CAO) at rest and subsequent reperfusion. We investigated whether late PC occurs after exercise-induced ischemia (high-flow ischemia) in dogs. A circumflex coronary artery stenosis (by using occluders) was set up before the onset of treadmill exercise in nine chronically ...
Thorén A A Department of Cardiothoracic Anesthesia and Intensive Care, Sahlgrenska University Hospital, Göteborg, - - 2001
In the present study, the effects of mild hypothermic (34 degrees C) cardiopulmonary bypass (CPB) on jejunal mucosal perfusion (JMP), gastric tonometry, splanchnic lactate, and oxygen extraction were studied in low-risk cardiac surgical patients (n = 10), anesthetized and managed according to clinical routine. JMP was assessed by endoluminal laser ...
Mocanu M M - - 2000
There is debate concerning the involvement of p38 mitogen activated protein kinase (MAPK) in the mediation of ischaemic preconditioning. Pharmacological inhibition of p38 MAPK with SB203580 has been reported to block preconditioning in some studies but not in others. We hypothesised that this divergence could be due to differences in ...
Ghosh S - - 2000
BACKGROUND: There are reports suggesting that cardiotrophin 1 (CT-1) is cytoprotective. We investigated the cardioprotective effects of CT-1 on the human myocardium and compared this benefit with the early and delayed protection afforded by ischemic preconditioning (PC). METHODS: Right atrium specimens were prepared and incubated in buffer solution at 37 ...
Pawlik W W - - 2000
Calcitonin gene related peptide (CGRP) is widely distributed in the myenteric neurons along GI tract. Biological effects of CGRP on gastrointestinal tract include increase in the intestinal blood flow, relaxation of the smoth muscle and slight increase in the slow wave amplitude (SWA) with no effect on frequency (SWF) of ...
Mitsuoka H - - 2000
Our recent results indicate that pancreatic enzymes in the ischemic intestine are involved in the production of in vivo activators, which stimulate cells in the cardiovascular system and initiate multiple organ failure. Since the intestine is a rich source of xanthine oxidase (XO), we investigated whether XO may be involved ...
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