Search results for "Perfusion"

Detrimental Effects of 60 kHz Sonothrombolysis in Rats with Middle Cerebral Artery Occlusion

2008

Recent studies have raised concerns about the safety of low frequency ultrasound in transcranial therapeutic application in cerebral ischemia. This study was designed to evaluate safety aspects and potential deleterious effects of low frequency, 60 kHz ultrasound in treatment of experimental middle cerebral artery occlusion (MCAO) in rats. Forty-five male Wistar rats were submitted to either temporary (90 min; groups I and II) or permanent MCAO (groups III and IV) using the suture technique. All animals received recombinant tissue plasminogen activator (rt-PA) starting 90 min after the beginning of occlusion. Groups I and III were additionally treated with 60 kHz ultrasound (time average ac…

Nitric oxide synthase neurons in the rodent spinal cord: distribution, relation to Substance P fibers, and effects of dorsal rhizotomy.

2001

The indirect immunofluorescent method was employed to investigate the distribution of neuronal nitric oxide synthase-like immunoreactivity(nNOS-LI) in the spinal cord of the golden hamster and to compare it to data obtained from rats. Immunoreactive neurons were found throughout the cervico-sacral extent in the dorsal horn (mainly in laminae I-III) and in the preganglionic autonomic regions, i.e., the sympathetic intermediolateral nucleus (IML), lateral funicle (LF), intercalated region (IC), the area surrounding the central canal (CA), and the sacral preganglionic parasympathetic cell group. While the distribution of immunoreactive cells was generally similar in both species, some differen…

Effect of surfactants on Albendazole absorption

1991

Staphylococcal α-toxin provokes coronary vasoconstriction and loss in myocardial contractility in perfused rat hearts: Role of thromboxane generation

2000

Background —Cardiac performance is severely depressed in septic shock. Endotoxin has been implicated as the causative agent in Gram-negative sepsis, but similar abnormalities are encountered in Gram-positive sepsis. We investigated the influence of the major exotoxin of Staphylococcus aureus, staphylococcal α-toxin, in isolated perfused rat hearts. Methods and Results —α-Toxin 0.25 to 1 μg/mL caused a dose-dependent increase in coronary perfusion pressure that more than doubled. In parallel, we noted a decrease in left ventricular developed pressure and the maximum rate of left ventricular pressure rise (dP/dt max ), dropping to a minimum of <60% of control. These changes were accompani…

Do randomized clinical trial selection criteria reflect levels of risk as observed in a general population of acute myocardial infarction survivors? …

2016

IF 4.638; International audience; Background: Few clinical trials have focused on populations with a history of distant myocardial infarction (MI). The PEGASUS trial assessed the impact of dual antiplatelet therapy in such patients, selected by enrichment criteria of high cardiovascular risk. Whether the PEGASUS population reflects the risk of a broader post-MI population is questionable. We analyzed whether 4-year mortality of a routine-practice population would differ according to the inclusion and exclusion criteria used in PEGASUS.Methods: FAST-MI is a nationwide French registry recruiting acute MI patients in November 2005; 2490 patients alive and without recurrent MI at one year were …

Shunting of the Microcirculation After Mesenteric Ischemia and Reperfusion Is a Function of Ischemia Time and Increases Mortality

2006

Shunting of the microcirculation contributes to the pathology of sepsis and septic shock. The authors address the hypothesis that shunting of the microcirculation occurs after superior mesenteric artery occlusion (SMAO) and reperfusion, and explore functional consequences.Spontaneously breathing animals (rats) (n = 30) underwent SMAO for 0 (controls), 30 (SMAO_30) or 60 min (SMAO_60) followed by reperfusion (4 h) with normal saline. Leukocyte-endothelial interactions in mesenteric venules were quantified in an exteriorized ileal loop using intravital microscopy. Abdominal blood flow was recorded continuously, and arterial blood gases were analyzed at intervals. The above groups were matched…

An early bolus of hypertonic saline hydroxyethyl starch improves long-term outcome after global cerebral ischemia.

2006

Objective: The beneficial effect of hypertonic saline solutions in the emergency treatment of shock and traumatic brain injury is well described. The present study determines effects of a single bolus of hypertonic saline on long-term survival, neurologic function, and neuronal survival 10 days after global cerebral ischemia. In addition, we evaluated the therapeutic window for hypertonic saline treatment (early vs. delayed application). Design: Laboratory experiment. Setting: University laboratory. Subjects: Male Wistar rats weighing 240‐330 g. Interventions: Rats were submitted to temporal global cerebral ischemia using temporary bilateral carotid occlusion combined with hypobaric hypoten…

Sex differences in mortality in stable patients undergoing vasodilator stress cardiovascular magnetic resonance

2021

Abstract Introduction The prognostic value and therapeutic implications of ischemia as derived from vasodilator stress cardiovascular magnetic resonance (CMR) could differ in men and women, but it has not been stablished. Purpose We assessed the influence of the ischemic burden as derived from CMR on the risk of death and the effect of revascularization across sex. Methods We evaluated 6,237 consecutive patients with known or suspected chronic coronary syndrome (CCS). Extensive ischemia was defined as >5 segments with perfusion deficit. Multivariate Cox proportional hazard regression models were used. Results A total of 2,371 (38.0%) patients were women and 583 (9.3%) underwent CMR-r…

Prognostic implications of dipyridamole cardiac MR imaging: a prospective multicenter registry

2011

Purpose: To evaluate dipyridamole cardiac magnetic resonance (MR) imaging in the prediction of major events (MEs) in patients with ischemic chest pain in a large multicenter registry. Materials and Methods: Institutional ethics committee approval and written informed consent were obtained. A total of 1722 patients who were undergoing cardiac MR imaging for chest pain were included. Wall motion abnormalities (WMAs) at rest, hyperemia perfusion defect (PD), late gadolinium enhancement (LGE), and inducible WMA were analyzed (abnormal if more than one abnormal segment was seen) with the 17-segment model. A cardiac MR categorization was created: category 1, no PD, LGE, or inducible WMA; category…

Usefulness of a Comprehensive Cardiovascular Magnetic Resonance Imaging Assessment for Predicting Recovery of Left Ventricular Wall Motion in the Set…

2005

ObjectivesWe sought to evaluate the usefulness of a comprehensive assessment of four cardiovascular magnetic resonance imaging (CMR)-derived myocardial viability indexes in the setting of myocardial stunning.BackgroundCardiovascular magnetic resonance imaging allows the simultaneous assessment of several viability indexes.MethodsWe studied 40 patients with a first ST-segment elevation myocardial infarction (MI) and an open infarct-related artery. At the first week, using CMR, wall motion (WM), and four viability indexes were determined: wall thickness, WM improvement with low-dose dobutamine, perfusion, and transmural extent of necrosis. We created a comprehensive score based on the presenc…