Search results for "reperfusion"

Characterization of the cortical laser-doppler flow and hippocampal degenerative patterns after global cerebral ischaemia in the goat.

1998

Large-animal models offer several advantages in the study of cerebral ischaemia: easier control of physiological variables, easier neuropathological evaluation, etc. In the present study we have taken advantage of the unique cerebrovascular anatomy of the goat to reproduce a model of reversible, incomplete, global cerebral ischaemia in a large-sized animal species, in which the effects of successive manoeuvres to stop and re-start cerebral blood flow can be recorded continuously. Early cortical laser-Doppler flow response (up to 2 h) and delayed neuronal degeneration (7 days) in the hippocampal CA1 subfield have been analysed in goats undergoing 5, 10 or 20 min of transient, global cerebral…

Destruction of Kupffer’s cells increases total liver blood flow and decreases ischemia reperfusion injury in pigs

2000

Hypothermic preservation of lung allograft inhibits cytokine-induced chemoattractant-1, endothelial leucocyte adhesion molecule, vascular cell adhesi…

2007

Summary Organ dysfunction is a major clinical problem after lung transplantation. Prolonged cold ischaemia and reperfusion injury are believed to play a central role in this complication. The influence of cold preservation on subsequent warm reperfusion was studied in an isolated, ventilated and perfused rat lung. Rat lungs were flushed with cold Perfadex-solution and stored at 4°C for different time periods. Thereafter lungs were perfused and ventilated for up to 3 h. Physiological parameters, production of inflammatory mediators and leucocyte infiltration were measured before and after perfusion. Lungs subjected to a cold ischaemia time of up to 6 h showed stable physiological conditions …

Intravenous BQ-123 and phosphoramidon reduce ventricular ectopic beats and myocardial infarct size in dogs submitted to coronary occlusion and reperf…

2001

Abstract The aim of this work was to investigate the influence of endothelin on myocardial ischemia and reperfusion in anaesthetized dogs. Animals were submitted to left thoracotomy and 120 min of left anterior descending coronary occlusion, followed by 180 min of reperfusion. Arterial blood pressure and electrocardiogram (ECG) were recorded in order to analyze heart rate (HR)–pressure product and production of ectopic beats. Infarcted areas were identified by a macroscopic staining method and infarct size was expressed as percentage of risk zone. To inhibit the effects of endothelin in a group of animals, we administered intravenously an endothelin synthesis inhibitor (phosphoramidon) and …

Polynitroxylated hemoglobin-based oxygen carrier: inhibition of free radical-induced microcirculatory dysfunction.

1999

Reactive oxygen species have been identified as key mediators of leukocyte/endothelial cell interaction under various pathological conditions and diseases such as ischemia/reperfusion injury, inflammation, and after exposure to cigarette smoke. Consequently, antioxidants have been shown to successfully prevent the sequelae of these conditions, ranging from tissue infarction to atherogenesis. In this study we investigated whether, via its established superoxide dismutase-like activity, a novel polynitroxyl hemoglobin-based oxygen carrier (PNH), could affect the stimulation of leukocyte rolling and adhesion to endothelial cells in response to cigarette smoke. Using the dorsal skin fold chambe…

[Role of visual analysis of first-pass contrast-enhanced MRI in reperfused myocardial infarction].

2006

The aim of this work is to evaluate the relationship between improvement of regional myocardial function and visual analysis of contrast-enhanced (CE) MRI in patients after acute myocardial infarction. MRI was performed on 19 patients 1 and 11 weeks after a reperfused acute myocardial infarction. Perfusion data (first-pass images [FPI] and delayed CE images) were acquired after an intravenous bolus of gadolinium-DTPA and visually analyzed using a 17 segment model. Each segment was then classified in 3 groups, according to the presence or absence of FPI and CE patterns at baseline study: group 0: normal-appearing segments; group 1: segments with delayed hyper-enhancement but no early hypo-en…

Area at Risk and Viability after Myocardial Ischemia and Reperfusion Can Be Determined by Contrast-Enhanced Cardiac Magnetic Resonance Imaging

2008

<i>Background/Aims:</i> Clinical differentiation between infarcted and viable myocardium in the ischemic area at risk is controversial. We investigated the potential of contrast-enhanced cardiac magnetic resonance imaging (ceCMRI) in determining the area at risk 24 h after ischemia. <i>Methods:</i> Myocardial ischemia was induced by percutaneous coronary intervention of the left anterior descending coronary artery in pigs. Coronary occlusion time was 30 min in group A, which caused little myocardial infarction and 45 min in group B, which led to irreversible damage. 24 h after reperfusion ceCMRI was performed at 2 and 15 min after administration of gadolinium-diethyl…

Heart-targeted overexpression of caspase3 in mice increases infarct size and depresses cardiac function

2001

Up-regulation of proapoptotic genes has been reported in heart failure and myocardial infarction. To determine whether caspase genes can affect cardiac function, a transgenic mouse was generated. Cardiac tissue-specific overexpression of the proapoptotic gene Caspase3 was induced by using the rat promoter of α-myosin heavy chain, a model that may represent a unique tool for investigating new molecules and antiapoptotic therapeutic strategies. Cardiac-specific Caspase3 expression induced transient depression of cardiac function and abnormal nuclear and myofibrillar ultrastructural damage. When subjected to myocardial ischemia–reperfusion injury, Caspase3 transgenic mice showed increased inf…

The effect of ischemia/reperfusion on the kidney graft.

2014

Ischemia/reperfusion injury is an unavoidable companion after kidney transplantation and influences short-term as well as long-term graft outcome. Clinically ischemia/reperfusion injury is associated with delayed graft function, graft rejection, and chronic graft dysfunction. Ischemia/reperfusion affects many regulatory systems at the cellular level as well as in the renal tissue that eventually result in a distinct inflammatory reaction of the kidney graft.Underlying factors include energy metabolism, cellular changes of the mitochondria and cellular membranes, initiation of different forms of cell death-like apoptosis and necrosis together with a recently discovered mixed form termed necr…

Comparison of two different techniques of reperfusion in adult orthotopic liver transplantation

2006

: The aim of this study was to determine the impact of two reperfusion techniques on the peri-operative hemodynamic changes and early post-operative graft function of adult patients undergoing orthotopic liver transplantation. Material and methods: From June 2003 to May 2004, 50 consecutive liver transplants were performed and divided into two groups: group A, 25 patients, portal vein flush with 500 cm3 of Ringer's lactate without vena caval venting. Group B, 25 patients, vena caval venting with no portal vein flush. Donor and recipient characteristics were similar in both groups. Sixty-four different parameters were analyzed, and Pearson's χ2 test and t-test were used for statistical analy…