Search results for "Perfusion"
showing 10 items of 714 documents
Aprotinin inhibits leukocyte–endothelial cell interactions after hemorrhage and reperfusion
2003
Background. The serine protease inhibitor aprotinin has been successfully used to reduce blood loss in patients undergoing cardiac operations. We studied aprotinin for its ability to modulate leukocyte– endothelial cell interactions after ischemia and reperfusion. Methods. The effects of aprotinin on leukocyte– endothelial cell interactions were observed by intravital microscopy in the rat mesenteric microcirculation and immunohistochemical analysis. The inflammatory cascade (leukocyte rolling, firm adherence, and transmigration) was studied after thrombin stimulation and after hemorrhage and reperfusion. Results. Intravenous bolus administration of aprotinin treatment (20,000 U/kg) signifi…
Adjunct Perfusion Branch for Reduction of Spinal Cord Ischemia in the Endovascular Repair of Thoracoabdominal Aortic Aneurysms
2017
Background To analyze utilization of a perfusion branch for temporary sac perfusion to reduce the spinal cord ischemia (SCI) in the endovascular repair of thoracoabdominal aortic aneurysms (TAAAs). Methods Between January 2012 and August 2016, 30 patients (18, men; median age 72 years) were treated for TAAAs with total endovascular repair using customized branched/fenestrated endografts in our institution. The median aneurysm size was 6.6 cm. Types of TAAA were: type I, 9 (30%), type II, 5 (16.6%), type III, 4 (13.3%), type IV, 6 (20%), and type V, 6 (20%). Ten patients received a perfusion branch to create an intentional endoleak, which was occluded with vascular plugs in mean interval ti…
Co-localisation of hypoxia and perfusion markers with parameters of glucose metabolism in human squamous cell carcinoma (hSCC) xenografts
2009
Purpose: To examine relationships between tumour hypoxia, perfusion and metabolic microenvironment at themicroregional level in three different human squamous cell carcinomas (hSCC). Materials and methods: Nude mice bearing FaDu, UT-SCC-15, and UT-SCC-5 hSCC were injected with pimonidazole hypoxia and Hoechst perfusion markers. Bioluminescence imaging was used to determine spatial distribution of glucose and lactate content in serial tumour sections. Metabolite levels were grouped in 10 concentration ranges. Images were co-registered and at each concentration range the proportion of area stained for pimonidazole and Hoechst was determinedin 1113 tumours per tumour line. Results: The spatia…
C1-Esterase-Inhibitor Treatment at Early Reperfusion of Hemorrhagic Shock Reduces Mesentery Leukocyte Adhesion and Rolling
2001
Objective: Complement activation probably plays a pathogenic role in multiple organ failure in shock. This study evaluates the effects of C1-esterase-inhibitor treatment on leukocyte-endothelial interaction in the mesenteric microcirculation in hemorrhagic shock. Methods: Rats underwent median laparotomy and exteriorization of an ileal loop for intravital microscopy of the mesenteric microcirculation. Volume controlled hemorrhagic shock was provoked by arterial blood withdrawal (2.5 mL/ 100 g body wt. for 60 minutes) followed by a 4-hour reperfusion period. C1-INH (100 IU/kg body wt. i.v.) or 0.9% NaCl i.v. were administered as a bolus at the beginning of reperfusion. Reperfusion time mimic…
Two‐dimensional analysis of myocardial protein expression following myocardial ischemia and reperfusion in rabbits
2002
Myocardial ischemia and reperfusion injury (MI/R) can be related to leukocyte activation with subsequent release of cytokines and oxygen derived free radicals. Activation of the complement system has been implicated in the pathogenesis of myocardial ischemia and reperfusion injury. Inflammatory injury will subsequently result in cellular activation and protein synthesis. In the present study we analyzed the myocardial protein expression and its pattern following myocardial ischemia and reperfusion, with and without complement inhibition with the synthetic serine protease inhibitor Futhan/nafamstat mesilate (FUT-175) known to inhibit classical and alternative complement pathway in a rabbit m…
Temperature-dependent effects of increased intraluminal pressure on serotonin release from the vascularly perfused guinea pig ileum
1987
Isolated segments of the guinea pig ileum were vascularly perfused and the release of endogenous serotonin into the portal effluent was measured. Peristalsis was induced by raising the intraluminal hydrostatic pressure by 500 Pa for 5 min. Serotonin release increased during peristalsis induced by fluid of 37 degrees C, but decreased when the temperature of the intraluminal fluid was between 13 degrees C and 22 degrees C. In the presence of naloxone (0.3 mumol/l) raising the intraluminal pressure with fluid of 37 degrees C caused an inhibition of the serotonin release which was blocked by scopolamine (0.1 mumol/l). Naloxone did not affect the inhibition of serotonin release during peristalsi…
Histamine and serotonin released from the rat perfused heart by compound 48/80 or by allergen challenge influence noradrenaline or acetylcholine exoc…
1994
Terminal nerve fibres of the autonomic nervous system closely approach mast cells in peripheral organs, and mutual influences between release of neurotransmitters or mast cell mediators may cause neuro-immunological interactions. We have studied the influence of mast cell degranulation on the release of endogenous noradrenaline and newly incorporated acetylcholine (such as 14C-choline/acetylcholine overflow) evoked by stimulation of extrinsic postganglionic sympathetic or preganglionic vagal nerves in the rat Langendorff heart perfused with Tyrode solution. Compound 48/80 perfused in normal hearts, or ovalbumin infused into hearts from rats sensitized to ovalbumin, enhanced the overflow of …
Adrenergic modulation of the release of 5-hydroxytryptamine from the vascularly perfused ileum of the guinea-pig
1988
1. Isolated segments of the guinea-pig ileum were vascularly perfused and the release of 5-hydroxytryptamine (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) into the portal venous effluent was determined by h.p.l.c. with electrochemical detection. Test substances were applied via the arterial perfusion medium. 2. Isoprenaline (0.1 microM) increased the outflow of 5-HT and 5-HIAA maximally by about 75% and this was antagonized by propranolol (0.1 microM). Forskolin (1-10 microM) increased the outflow of 5-HT by approximately 105% and that of 5-HIAA by approximately 55%. The phosphodiesterase inhibitor AH 21-132 (0.1-1 microM) increased the outflow of 5-HT and 5-HIAA by about 70%. Isoprenaline…
Cisplatin increases the release of 5-hydroxytryptamine (5-HT) from the isolated vascularly perfused small intestine of the guinea-pig: Involvement of…
1991
Isolated segments of the guinea-pig small intestine were vascularly perfused and the release of 5-hydroxytryptamine (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) into the portal venous effluent determined by high pressure liquid chromatography with electrochemical detection. Release of acetylcholine from isolated superfused intestinal segments was determined as outflow of [3H]radioactivity from preparations preincubated with [3H]choline. Cisplatin (3 microM) increased the outflow of 5-HT and 5-HIAA by about 90%. At 30 and 100 microM cisplatin decreased the outflow of 5-HT and its metabolite by 40%-50%. The stimulatory effect of cisplatin was consistently observed only when the bicarbonate-…
Intestinal transport of cefuroxime axetil in rats: absorption and hydrolysis processes.
2002
Studies were performed using three cefuroxime axetil solutions (11.8, 118 and 200 microM) in three selected intestinal segments and one cefuroxime axetil solution (118 microM) in colon of anaesthetized rats. First-order absorption rate pseudoconstants, k(ap) and effective permeability coefficients, P(eff), were calculated in each set. Absorption of cefuroxime axetil can apparently be described as a carrier-mediated transport, which obeys Michaelis-Menten and first order kinetics in the proximal segment of the small intestine and a passive diffusion mechanism in the mean and distal segments. The absorption kinetic parameters for cefuroxime axetil were obtained: Vm=0.613 (0.440) microM min-1;…