The Experts below are selected from a list of 237 Experts worldwide ranked by ideXlab platform
E A Rasio - One of the best experts on this subject based on the ideXlab platform.
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the Rete Mirabile of the eel a useful model for the study of transcapillary passage of mr contrast agents
Journal of Magnetic Resonance Imaging, 1999Co-Authors: N Siauve, E A Rasio, Moise Bendayan, C A Cuenod, Olivier Clement, G FrijaAbstract:Our purpose was to study the capillary leakage of MR contrast media using a pure capillary model, the Rete Mirabile of the eel. The Rete is a countercurrent-exchange organ composed of an arterial and a venous capillary system that can be catheterized and perfused. Substances are introduced at the arterial input by a constant infusion, and their steady-state concentrations are measured at the arterial and venous outputs. The capillary leakage of four MR contrast agents--Gd-DOTA(MW = 561 D), carboxymethyldextran-Gd-DTPA (MW = 38,900 D), albumin-Gd-DTPA (MW = 92,000 D), AMI-227 (400,000 D
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The Rete Mirabile of the eel: a useful model for the study of transcapillary passage of MR contrast agents.
Journal of magnetic resonance imaging : JMRI, 1999Co-Authors: N Siauve, E A Rasio, Moise Bendayan, C A Cuenod, Olivier Clement, G FrijaAbstract:Our purpose was to study the capillary leakage of MR contrast media using a pure capillary model, the Rete Mirabile of the eel. The Rete is a countercurrent-exchange organ composed of an arterial and a venous capillary system that can be catheterized and perfused. Substances are introduced at the arterial input by a constant infusion, and their steady-state concentrations are measured at the arterial and venous outputs. The capillary leakage of four MR contrast agents--Gd-DOTA(MW = 561 D), carboxymethyldextran-Gd-DTPA (MW = 38,900 D), albumin-Gd-DTPA (MW = 92,000 D), AMI-227 (400,000 D
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transport of insulin and albumin by the microvascular endothelium of the Rete Mirabile
Journal of Cell Science, 1996Co-Authors: Moise Bendayan, E A RasioAbstract:Vascular permeability for albumin and insulin in the continuous capillary network of the Rete Mirabile of the eel swimbladder was evaluated by ultrastructural immunocytochemistry and countercurrent perfusion experiments. Upon perfusion of the Rete capillaries with a buffer solution containing albumin and insulin, these serum proteins were revealed at the electron microscope level, by the Protein A-gold immunocytochemical technique on a post-embedding step. For the simultaneous detection of both proteins, the double labeling technique with different sized gold particles was used. Furthermore, labeling was performed with the mixture of anti-albumin and anti-insulin anti-bodies. The labelings obtained were morphometrically evaluated and demonstrate that: (1) serum proteins such as albumin and insulin are transported by the endothelial cells through their plasmalemmal vesicular system; (2) insulin is transported preferentially to albumin; and (3) this transport involves different populations of plasmalemmal vesicles. Measurements of diffusion permeability coefficients have confirmed the preferential transport of insulin, its coefficient being higher than that of albumin. Conversely, when compared to that of insulin or sucrose, which are assumed to be markers of the paracellular diffusion, it was found to be much lower, indicating that transcytosis through the vesicular system is less efficient than diffusion along the intercellular junctions. These results indicate that transcytosis of insulin and albumin occurs via different sets of plasmalemmal vesicles, probably through receptor-mediated mechanisms, and that the overall rate of transport across the Rete capillaries, with respect to paracellular diffusion, is higher for insulin than for albumin.
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le Rete Mirabile de l anguille un modele unique pour l etude de la permeabilite capillaire
M S-medecine Sciences, 1993Co-Authors: E A Rasio, M Bendayan, C A GoreskyAbstract:Le Rete Mirabile de la vessie natatoire de l'anguille est un organe microvasculaire d'un grand interet dans le domaine de la physiopathologie de la permeabilite capillaire. La presence de deux retia symetriques a la surface de la vessie presente l'avantage de pouvoir analyser simultanement les relations entre la structure, la biochimie et la fonction de l'endothelium capillaire, tant a l'etat normal qu'apres stimulation aigue ou chronique par divers agents physiques et chimiques. La morphologie fine des capillaires, la composition de leurs membranes basales, leurs proprietes metaboliques et fonctionnelles sont comparables a celles que l'on a decrites chez le mammifere dans des capillaires de meme type
F Vinuela - One of the best experts on this subject based on the ideXlab platform.
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Arteriovenous malformation animal model for radiosurgery: the Rete Mirabile.
AJNR. American journal of neuroradiology, 1996Co-Authors: A. A. F. De Salles, Timothy D. Solberg, Paul S. Mischel, Tarik F. Massoud, A.r. Plasencia, S. Goetsch, E. De Souza, F VinuelaAbstract:PURPOSE To study the effects of single-dose radiation on the porcine Rete Mirabile, a tangle of microvessels that mimics human arteriovenous malformations of the brain. METHODS Eight retia mirabilia received a single dose of radiation under stereotactic location with digital angiography and CT. The following doses were applied: 20, 30, 40, 50, 60, 70, 80, and 90 Gy. The animals were followed up for a period of 7 months. Findings at neurologic examination, serial angiography, and histopathologic examination were analyzed. RESULTS Progressive occlusion as observed by angiography corresponded to the histopathologic finding of intimal hyperplasia; that is, marked thickening of the vessel wall, progressing to occlusion of the vascular lumen, and associated thrombosis. A direct dose response was noted for these changes. Neurologic findings were related to the dose distribution and to histologic findings in structures adjacent to the Rete Mirabile. CONCLUSION The Rete Mirabile is an excellent model by which to study the radiologic and histologic effects of single-dose radiation to the microvasculature of the central nervous system.
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Collagen microbeads: experimental evaluation of an embolic agent in the Rete Mirabile of the swine.
AJNR. American journal of neuroradiology, 1995Co-Authors: F. Turjman, Tarik F. Massoud, Harry V. Vinters, Tardy M, Guido Guglielmi, F VinuelaAbstract:PURPOSE To evaluate the histologic and angiographic effects of collagen microbeads as an embolic agent in the swine Rete Mirabile. METHODS Human collagen particles (380 +/- 100 microns) of spheroidal shape and smooth surface were used to embolize the Rete Mirabile in five swine. Control angiograms and pathologic examinations were obtained immediately and sequentially from 3 to 35 days after embolization. RESULTS The collagen particles were easy to inject through microcatheters. Embolization was always angiographically complete and persistent for at least 5 weeks. Histologic studies showed occlusion of 25% to 50% of the Rete vessels. After 3 and 5 weeks9 follow-up, transmural and adventitial chronic inflammation was present. Inflammatory infiltrates included lymphohistiocytic cells and scattered eosinophils. The foreign-body giant-cell reaction was pronounced. No evidence of angionecrosis or focal hemorrhage was shown. CONCLUSIONS Collagen microbeads are a promising experimental embolic agent, with potential future applications in humans.
Moise Bendayan - One of the best experts on this subject based on the ideXlab platform.
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the Rete Mirabile of the eel a useful model for the study of transcapillary passage of mr contrast agents
Journal of Magnetic Resonance Imaging, 1999Co-Authors: N Siauve, E A Rasio, Moise Bendayan, C A Cuenod, Olivier Clement, G FrijaAbstract:Our purpose was to study the capillary leakage of MR contrast media using a pure capillary model, the Rete Mirabile of the eel. The Rete is a countercurrent-exchange organ composed of an arterial and a venous capillary system that can be catheterized and perfused. Substances are introduced at the arterial input by a constant infusion, and their steady-state concentrations are measured at the arterial and venous outputs. The capillary leakage of four MR contrast agents--Gd-DOTA(MW = 561 D), carboxymethyldextran-Gd-DTPA (MW = 38,900 D), albumin-Gd-DTPA (MW = 92,000 D), AMI-227 (400,000 D
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The Rete Mirabile of the eel: a useful model for the study of transcapillary passage of MR contrast agents.
Journal of magnetic resonance imaging : JMRI, 1999Co-Authors: N Siauve, E A Rasio, Moise Bendayan, C A Cuenod, Olivier Clement, G FrijaAbstract:Our purpose was to study the capillary leakage of MR contrast media using a pure capillary model, the Rete Mirabile of the eel. The Rete is a countercurrent-exchange organ composed of an arterial and a venous capillary system that can be catheterized and perfused. Substances are introduced at the arterial input by a constant infusion, and their steady-state concentrations are measured at the arterial and venous outputs. The capillary leakage of four MR contrast agents--Gd-DOTA(MW = 561 D), carboxymethyldextran-Gd-DTPA (MW = 38,900 D), albumin-Gd-DTPA (MW = 92,000 D), AMI-227 (400,000 D
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transport of insulin and albumin by the microvascular endothelium of the Rete Mirabile
Journal of Cell Science, 1996Co-Authors: Moise Bendayan, E A RasioAbstract:Vascular permeability for albumin and insulin in the continuous capillary network of the Rete Mirabile of the eel swimbladder was evaluated by ultrastructural immunocytochemistry and countercurrent perfusion experiments. Upon perfusion of the Rete capillaries with a buffer solution containing albumin and insulin, these serum proteins were revealed at the electron microscope level, by the Protein A-gold immunocytochemical technique on a post-embedding step. For the simultaneous detection of both proteins, the double labeling technique with different sized gold particles was used. Furthermore, labeling was performed with the mixture of anti-albumin and anti-insulin anti-bodies. The labelings obtained were morphometrically evaluated and demonstrate that: (1) serum proteins such as albumin and insulin are transported by the endothelial cells through their plasmalemmal vesicular system; (2) insulin is transported preferentially to albumin; and (3) this transport involves different populations of plasmalemmal vesicles. Measurements of diffusion permeability coefficients have confirmed the preferential transport of insulin, its coefficient being higher than that of albumin. Conversely, when compared to that of insulin or sucrose, which are assumed to be markers of the paracellular diffusion, it was found to be much lower, indicating that transcytosis through the vesicular system is less efficient than diffusion along the intercellular junctions. These results indicate that transcytosis of insulin and albumin occurs via different sets of plasmalemmal vesicles, probably through receptor-mediated mechanisms, and that the overall rate of transport across the Rete capillaries, with respect to paracellular diffusion, is higher for insulin than for albumin.
Santiago Ortega-gutierrez - One of the best experts on this subject based on the ideXlab platform.
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In vivo evaluation of the new PHIL low viscosity in a swine Rete Mirabile model.
Interventional neuroradiology : journal of peritherapeutic neuroradiology surgical procedures and related neurosciences, 2018Co-Authors: Edgar A Samaniego, Colin P Derdeyn, Minako Hayakawa, David Hasan, Santiago Ortega-gutierrezAbstract:Introduction Few liquid embolic materials are available for treatment of arteriovenous malformations. We describe the in vivo experience with the new PHIL low viscosity (LV) liquid embolic agent in a swine Rete Mirabile model. Methods Eight swine were treated. Two animals underwent embolization of a Rete with PHIL LV and the contralateral Rete with Squid 12 (euthanized the same day). Six animals underwent embolization of the right Rete: two with balloon flow arrest (euthanized at 14 d) and four with a microcatheter alone (euthanized at 14 and 90 d). Performance characteristics of the embolic agents were evaluated. Microscopic and histological analysis of the harvested retia was performed. Macroscopic examinations and high contrast digital-based radiographs of the central nervous system were obtained. Results We did not experience any technical complication during embolization of each Rete. Overall occlusion ability, on/off injection and ease to retrieve the microcatheter/balloon with PHIL LV were optimal. Fluoroscopic visualization of the PHIL LV cast was adequate to optimal. Average embolization time with flow arrest was 9.5 min versus 19.5 min with microcatheter plugging. Embolizations with PHIL LV required less volume and were shorter when compared to Squid 12. Subacute (14 d) and chronic (90 d) microscopic and histological analysis demonstrated minimal inflammatory changes in the perivascular tissues and permanent occlusion of the embolized vasculature. Conclusion In this swine Rete model, the new PHIL LV embolic agent had an excellent embolization performance. Vessels embolized remained occluded up to 90 d from the procedure with minimal inflammatory changes.
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Supplemental material for In vivo evaluation of the new PHIL low viscosity in a swine Rete Mirabile model
2018Co-Authors: Edgar A Samaniego, Colin P Derdeyn, Minako Hayakawa, David Hasan, Santiago Ortega-gutierrezAbstract:Supplemental material for In vivo evaluation of the new PHIL low viscosity in a swine Rete Mirabile model by Edgar A Samaniego, Colin P Derdeyn, Minako Hayakawa, David Hasan and Santiago Ortega-Gutierrez in Interventional Neuroradiology
G Frija - One of the best experts on this subject based on the ideXlab platform.
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the Rete Mirabile of the eel a useful model for the study of transcapillary passage of mr contrast agents
Journal of Magnetic Resonance Imaging, 1999Co-Authors: N Siauve, E A Rasio, Moise Bendayan, C A Cuenod, Olivier Clement, G FrijaAbstract:Our purpose was to study the capillary leakage of MR contrast media using a pure capillary model, the Rete Mirabile of the eel. The Rete is a countercurrent-exchange organ composed of an arterial and a venous capillary system that can be catheterized and perfused. Substances are introduced at the arterial input by a constant infusion, and their steady-state concentrations are measured at the arterial and venous outputs. The capillary leakage of four MR contrast agents--Gd-DOTA(MW = 561 D), carboxymethyldextran-Gd-DTPA (MW = 38,900 D), albumin-Gd-DTPA (MW = 92,000 D), AMI-227 (400,000 D
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The Rete Mirabile of the eel: a useful model for the study of transcapillary passage of MR contrast agents.
Journal of magnetic resonance imaging : JMRI, 1999Co-Authors: N Siauve, E A Rasio, Moise Bendayan, C A Cuenod, Olivier Clement, G FrijaAbstract:Our purpose was to study the capillary leakage of MR contrast media using a pure capillary model, the Rete Mirabile of the eel. The Rete is a countercurrent-exchange organ composed of an arterial and a venous capillary system that can be catheterized and perfused. Substances are introduced at the arterial input by a constant infusion, and their steady-state concentrations are measured at the arterial and venous outputs. The capillary leakage of four MR contrast agents--Gd-DOTA(MW = 561 D), carboxymethyldextran-Gd-DTPA (MW = 38,900 D), albumin-Gd-DTPA (MW = 92,000 D), AMI-227 (400,000 D