Search results for " THROMBOSIS"
showing 10 items of 328 documents
Occlusion of the pig superior sagittal sinus, bridging and cortical veins: multistep evolution of sinus-vein thrombosis
1992
✓ Cerebral sinus-vein thrombosis may lead to severe hemodynamic changes, elevated intracranial pressure (ICP), and brain edema. It is supposed that progression of the thrombus from the sinus into bridging and cortical veins plays a key role in the development of these pathophysiological changes, but this hypothesis lacks experimental proof. The aim of this study, using a novel animal model of sinus-vein thrombosis, was to evaluate the effects of a standardized occlusion of the superior sagittal sinus and its bridging and cortical veins on hemodynamic alterations, on brain water content, and on ICP in domestic pigs. In 10 animals, the middle third of the superior sagittal sinus was occluded …
Local Cerebral Blood Flow in a Rat Cortical Vein Occlusion Model
1996
The symptoms following sinus and vein occlusion observed in patients and experimental animals display a considerable variability that so far remains largely unexplained. In a rat cortical vein occlusion model using a photochemical thrombotic technique, we examined changes in the cerebral venous flow pattern by fluorescence angiography and regional cerebral blood flow (rCBF) and cerebral blood volume fraction (CBVF) by a modern laser Doppler “scanning” technique. Brain damage was assessed histologically. Fluorescence angiographic findings fell into two groups: group A, rats with an altered venous flow pattern after occlusion (n = 12), and group B, rats with interruption of blood flow and/or…
Novel complement C1 inhibitor BSF468248 does not improve brain damage after cortical vein occlusion
2003
BSF468248 is a novel potent complement C1 inhibitor. To determine whether BSF468248 is effective against focal cerebral ischemia, we evaluated the change of cerebral blood flow (CBF) and infarction volume using a photochemically-induced cortical vein occlusion model in rats in blind studies. In 22 Wistar rats, two adjacent cortical veins were occluded by photochemical thrombosis and fiberoptic illumination under controlled anesthesia and ventilation. Just after the occlusion, BSF468248 or physiological saline was administrated. In the low-dose study, a treatment group (n = 7) was administered BSF468248 1 mg/kg bolus and 1 mg/kg continuously for 30 min. The same volume of saline was given to…
Cluster analysis of mrna expression levels identifies multiple sequential patterns following focal cerebral ischemia
2012
AIM The purpose of this study is to detect gene expression patterns following focal cerebral ischemia. MATERIAL AND METHODS 25 male Wistar rats were divided into control (n = 8) and ischemic (n = 17) groups. In the ischemic group, slowly progressing focal ischemia was simulated by two-vein occlusion with spreading depression (SD) a cortical microinjection of KCl induced. Ischemic tissue was removed at 2, 8, 24, or 72 h postischemia. Using semiquantitative reverse transcription polymerase chain reaction, we investigated mRNA expression levels of 13 representative genes related to cerebral ischemia. Cluster analysis of the gene expression levels was done. RESULTS In the ischemic group, the ex…
Venous and arterial thromboembolic complications in COVID-19 patients admitted to an academic hospital in Milan, Italy
2020
Background Few data are available on the rate and characteristics of thromboembolic complications in hospitalized patients with COVID-19. Methods We studied consecutive symptomatic patients with laboratory-proven COVID-19 admitted to a university hospital in Milan, Italy (13.02.2020–10.04.2020). The primary outcome was any thromboembolic complication, including venous thromboembolism (VTE), ischemic stroke, and acute coronary syndrome (ACS)/myocardial infarction (MI). Secondary outcome was overt disseminated intravascular coagulation (DIC). Results We included 388 patients (median age 66 years, 68% men, 16% requiring intensive care [ICU]). Thromboprophylaxis was used in 100% of ICU patients…
Incidence, risk factors, clinical characteristics and outcomes of deep venous thrombosis in patients with COVID-19 attending the Emergency Department…
2021
Background and importance A higher incidence of venous thromboembolism [both pulmonary embolism and deep vein thrombosis (DVT)] in patients with coronavirus disease 2019 (COVID-19) has been described. But little is known about the true frequency of DVT in patients who attend emergency department (ED) and are diagnosed with COVID-19. Objective We investigated the incidence, risk factors, clinical characteristics and outcomes of DVT in patients with COVID-19 attending the ED before hospitalization. Methods We retrospectively reviewed all COVID patients diagnosed with DVT in 62 Spanish EDs (20% of Spanish EDs, case group) during the first 2 months of the COVID-19 outbreak. We compared DVT-COVI…
Cardiovascular events and intensity of treatment in polycythemia vera.
2013
A b s t r ac t Background Current treatment recommendations for patients with polycythemia vera call for maintaining a hematocrit of less than 45%, but this therapeutic strategy has not been tested in a randomized clinical trial. Methods We randomly assigned 365 adults with JAK2-positive polycythemia vera who were being treated with phlebotomy, hydroxyurea, or both to receive either more intensive treatment (target hematocrit, <45%) (low-hematocrit group) or less intensive treatment (target hematocrit, 45 to 50%) (high-hematocrit group). The primary composite end point was the time until death from cardiovascular causes or major thrombotic events. The secondary end points were cardiovascula…
C4BPB/C4BPA is a new susceptibility locus for venous thrombosis with unknown protein S-independent mechanism: results from genome-wide association an…
2010
3 Figures. 2 Tables. The online version of this article contains a data supplement.
Dynamic in vivo Imaging of Microvasculature and Perfusion by Miniaturized Confocal Laser Microscopy
2008
<i>Introduction:</i> Microvasculature and associated pathologies mandate dynamic imaging. We evaluated a novel miniaturized confocal laser scanning probe for in vivo visualization of blood vessels, blood flow, cell tracking and perfusion in both healthy rodents and disease models.<i> Methods:</i> The hand-held confocal microscopy system allowed a 500- to 2,400-fold magnification at a dynamically variable imaging depth. Different intravital stains were used alone or in combination for tissue, nuclear, plasma and vascular endothelial cell staining and for blood flow visualization, and targeted staining for individual cell populations. <i>Results:</i> Precis…
A Scanning Technique to Measure Regional Cerebral Blood Flow and Oxyhemoglobin Level
2001
OBJECTIVE: The application of a laser scanning technique to measure regional cerebral blood flow (CBF) and tissue hemoglobin oxygenation (HbO 2 ) using the rat closed cranial window preparation is described. METHODS: Twenty-nine male Wistar rats were used to consecutively measure local CBF by laser Doppler flowmetry and tissue HbO 2 by a microspectrophotometric method at multiple corresponding cortical locations. The scanning technique used a computer-controlled micromanipulator. Data from three experimental models are presented: the whisker stimulation model, the ischemia-reperfusion model, and the sinus-vein thrombosis model. Sequential changes in local CBF and HbO 2 data before, during, …