23 resultados para Descending toracic aorta
em Consorci de Serveis Universitaris de Catalunya (CSUC), Spain
Resumo:
La reparació endovascular dels aneurismes d’aorta abdominal (AAA) és cada cop més usada, encara que només conta amb 15 anys des de l’inici amb una ràpida evolució. Davant la falta d’estudis amb resultats a més de 10 anys. L’objectiu del treball es analitzar prospectivament la supervivència dels 172 pacients tractats en nostre centre desde 06/1998 fins 01/2008, amb seguiment a 10 anys. S’obtingué una supervivència del 61% als 6 anys (error 5%), als 9 anys de 51% (error 7%), a 10 anys 47% (error 11%). La causa més freqüent de mort va ser per neoplàsia.
Resumo:
Una de les principals complicacions de la cirurgia de la dissecció aòrtica aguda és el dany neurològic. Entre els principals avenços per a la seva prevenció destaca el canvi de la perfusió arterial retrògrada a anterògrada a través de l’artèria axil•lar, amb la possibilitat de realitzar protecció cerebral. Hipòtesis de treball: L’ús de la canulació arterial axil•lar ha permès reduïr significativament l’incidència de complicacions neurològiques en la cirurgia de la dissecció aguda aòrtica. Material i mètodes: De manera retrospectiva, s’han comparat els pacients intervinguts de dissecció aòrtica aguda al llarg dels últims deu anys. Conclusió principal: L’ús de la canulació arterial axil•lar ha permès reduïr significativament l’incidència de complicacions neurològiques en la cirurgia de la dissecció aòrtica aguda del nostre centre.
Resumo:
El objetivo del estudio ha sido caracterizar mediante cardiorresonancia los fenotipos de válvula aórtica bicúspide (VAB) y su asociación con patrones de dilatación de aorta ascendente (AA). En este estudio la VAB fenotipo 1 (fusión velo coronario derecho -izquierdo) es la más prevalente y se asocia a coartación aórtica, insuficiencia aórtica moderada-severa y dilatación de raiz aórtica. El fenotipo 2 de VAB (fusión velo coronario derecho- no coronario) se asocia a dilatación de porción tubular aórtica. La edad predice dilatación de AA en pacientes con VAB y la estenosis aórtica moderada-severa es un factor protector contra dicha dilatación.
Resumo:
Estudi retrospectiu de pacients tractats d'aneurisma d'aorta abdominal, mitjangant reparació endovascular. Període reclutament: 2006 a 201,2. Van ser dividits en dos grups depenen de les característiques anatómiques del coll aórtic proximal, considerant si eren o no favorables pel tractament endovascular. L'objectiu de l'estudi és avaluar els resultats immediats del tractament en funció de la morfologia del coll aórtic. 95 pacients van ser inclosos (62 favorable, 33 hostil). S'analitzen els motius per considerar el coll com hostil, aixícom els resultats d'aquestes técniques. Conclusió: el tractament endovascular és una técriica válida per aquest tipus pacient amb colls aórtics no favorables.
Resumo:
El objetivo fundamental de este proyecto consiste en crear un generador de compilador, basado en analizadores ascendentes. Como base para hacer este analizador se usará el lenguaje Cosel y el módulo Com, que es un generador de compiladores basado en analizadores descendentes y que actualmente se está utilizando en las prácticas de la asignatura de Compiladores I. El nuevo generador, que tiene como entrada una gramática, ha de comprobar si es una gramática ascendente LALR (1) y analizar una cadena de entrada de símbolos usando dicha gramática.
Resumo:
La malaltia renal crònica terminal, el tractament substitutiu d'elecció és el trasplantament renal, és un problema de salut pública mundial en augment. L'envelliment de la població i la major prevalença de diabetis i hipertensió arterial en aquests pacients, s'associa a una major incidència de malaltia aorto-ilíaca i possible fracàs del ronyó trasplantat. En aquest treball es va analitzar l'evolució del filtrat glomerular en pacients trasplantats renals amb patologia aorto-ilíaca que van requerir cirurgia arterial prèvia o simultània al trasplantament renal, comparada amb un grup control sense patologia aorto-ilíaca. No es van trobar diferències estadísticament significatives entre ambdós grups.
Resumo:
Amyloid β-peptide (Aβ) fibril deposition on cerebral vessels produces cerebral amyloid angiopathy that appears in the majority of Alzheimer's disease patients. An early onset of a cerebral amyloid angiopathy variant called hereditary cerebral hemorrhage with amyloidosis of the Dutch type is caused by a point mutation in Aβ yielding AβGlu22→Gln. The present study addresses the effect of amyloid fibrils from both wild-type and mutated Aβ on vascular cells, as well as the putative protective role of antioxidants on amyloid angiopathy. For this purpose, we studied the cytotoxicity induced by Aβ1–40 Glu22→Gln and Aβ1–40 wild-type fibrils on human venule endothelial cells and rat aorta smooth muscle cells. We observed that AβGlu22→Gln fibrils are more toxic for vascular cells than the wild-type fibrils. We also evaluated the cytotoxicity of Aβ fibrils bound with acetylcholinesterase (AChE), a common component of amyloid deposits. Aβ1–40 wild-type–AChE fibrillar complexes, similar to neuronal cells, resulted in an increased toxicity on vascular cells. Previous reports showing that antioxidants are able to reduce the toxicity of Aβ fibrils on neuronal cells prompted us to test the effect of vitamin E, vitamin C, and 17β-estradiol on vascular damage induced by Aβwild-type and AβGlu22→Gln. Our data indicate that vitamin E attenuated significantly the Aβ-mediated cytotoxicity on vascular cells, although 17β-estradiol and vitamin C failed to inhibit the cytotoxicity induced by Aβ fibrils.
Resumo:
While it is true that Latin American republics had no rival on maximising revenues from custom collection during the belle époque, this paper shows that Latin American countries were also generous importers, only behind the larger commercial countries of Western Europe in terms of imports per capita. Latin American citizens were much more linked to international trade than citizens of most regions of the world. Their relation to the world economy was tighter both via their imports and their exports relative to their population and income levels. This paper comes to show that there is no contradiction between the high custom collection by the Latin American republics and their high level of interaction with the global economy in the pre-1914 belle époque, although large country differences can be observed when descending from the regional to the national level.
Resumo:
We study the induced aggregation operators. The analysis begins with a revision of some basic concepts such as the induced ordered weighted averaging (IOWA) operator and the induced ordered weighted geometric (IOWG) operator. We then analyze the problem of decision making with Dempster-Shafer theory of evidence. We suggest the use of induced aggregation operators in decision making with Dempster-Shafer theory. We focus on the aggregation step and examine some of its main properties, including the distinction between descending and ascending orders and different families of induced operators. Finally, we present an illustrative example in which the results obtained using different types of aggregation operators can be seen.
Resumo:
We study the induced aggregation operators. The analysis begins with a revision of some basic concepts such as the induced ordered weighted averaging (IOWA) operator and the induced ordered weighted geometric (IOWG) operator. We then analyze the problem of decision making with Dempster-Shafer theory of evidence. We suggest the use of induced aggregation operators in decision making with Dempster-Shafer theory. We focus on the aggregation step and examine some of its main properties, including the distinction between descending and ascending orders and different families of induced operators. Finally, we present an illustrative example in which the results obtained using different types of aggregation operators can be seen.
Resumo:
Stress-strain trajectories associated with pseudoelastic behavior of a Cu¿19.4 Zn¿13.1 Al (at.%) single crystal at room temperature have been determined experimentally. For a constant cross-head speed the trajectories and the associated hysteresis behavior are perfectly reproducible; the trajectories exhibit memory properties, dependent only on the values of return points, where transformation direction is reverted. An adapted version of the Preisach model for hysteresis has been implemented to predict the observed trajectories, using a set of experimental first¿order reversal curves as input data. Explicit formulas have been derived giving all trajectories in terms of this data set, with no adjustable parameters. Comparison between experimental and calculated trajectories shows a much better agreement for descending than for ascending paths, an indication of a dissymmetry between the dissipation mechanisms operative in forward and reverse directions of martensitic transformation.
Resumo:
Normalization of the increased vascular nitric oxide (NO) generation with low doses of NG-nitro-L-arginine methyl ester (L-NAME) corrects the hemodynamic abnormalities of cirrhotic rats with ascites. We have undertaken this study to investigate the effect of the normalization of vascular NO production, as estimated by aortic cyclic guanosine monophosphate (cGMP) concentration and endothelial nitric oxide synthase (eNOS) protein expression in the aorta and mesenteric artery, on sodium and water excretion. Rats with carbon tetrachloride-induced cirrhosis and ascites were investigated using balance studies. The cirrhotic rats were separated into two groups, one receiving 0.5 mg/kg per day of L-NAME (CIR-NAME) during 7 d, whereas the other group (CIR) was administrated the same volume of vehicle. Two other groups of rats were used as controls, one group treated with L-NAME and another group receiving the same volume of vehicle. Sodium and water excretion was measured on days 0 and 7. On day 8, blood samples were collected for electrolyte and hormone measurements, and aorta and mesenteric arteries were harvested for cGMP determination and nitric oxide synthase (NOS) immunoblotting. Aortic cGMP and eNOS protein expression in the aorta and mesenteric artery were increased in CIR as compared with CIR-NAME. Both cirrhotic groups had a similar decrease in sodium excretion on day 0 (0.7 versus 0.6 mmol per day, NS) and a positive sodium balance (+0.9 versus +1.2 mmol per day, NS). On day 7, CIR-NAME rats had an increase in sodium excretion as compared with the CIR rats (sodium excretion: 2.4 versus 0.7 mmol per day, P < 0.001) and a negative sodium balance (-0.5 versus +0.8 mmol per day, P < 0.001). The excretion of a water load was also increased after L-NAME administration (from 28+/-5% to 65+/-7, P < 0.05). Plasma renin activity, aldosterone and arginine vasopressin were also significantly decreased in the CIR-NAME, as compared with the CIR rats. The results thus indicate that normalization of aortic cGMP and eNOS protein expression in vascular tissue is associated with increased sodium and water excretion in cirrhotic rats with ascites.
Resumo:
Early repolarization, which is characterized by an elevation of the J-point on 12-lead electrocardiography, is a common finding that has been considered as benign for decades. However, in the last years, it has been related with vulnerability to idiopathic ventricular fibrillation and with cardiac mortality in the general population. Recently, 4 potential ECG predictors that could differentiate the benign from the malignant form of early repolarization have been suggested. Any previous study about early repolarization has been done in Spain. Aim. To ascertain whether the presence of early repolarization pattern in a resting electrocardiogram is associated with a major risk of cardiac death in a Spanish general population and to determine whether the presence of potential predictors of malignancy in a resting electrocardiogram increases the risk of cardiac mortality in patients with early repolarization pattern. Methods. We will analyse the presence of early repolarization and the occurrence of cardiac mortality in a retrospective cohort study of 4,279 participants aged 25 to 74 years in the province of Girona. This cohort has been followed during a mean of 9.8 years. Early repolarization will be stratified according to the degree of J-point elevation (≥0.1 mV or ≥0.2 mV), the morphology of the J-wave (slurring, notching or any of these two), the ST-segment pattern (ascending or descending) and the localization (inferior leads, lateral leads, or both). Association of early repolarization with cardiac death will be assessed by adjusted Cox-proportional hazards models
Resumo:
Background: We report the case of a chronic stroke patient (62 months after injury) showing total absence of motor activity evoked by transcranial magnetic stimulation (TMS) of spared regions of the left motor cortex, but near-to-complete recovery of motor abilities in the affected hand. Case presentation: Multimodal investigations included detailed TMS based motor mapping, motor evoked potentials (MEP), and Cortical Silent period (CSP) as well as functional magnetic resonance imaging (fMRI) of motor activity, MRI based lesion analysis and Diffusion Tensor Imaging (DTI) Tractography of corticospinal tract (CST). Anatomical analysis revealed a left hemisphere subinsular lesion interrupting the descending left CST at the level of the internal capsule. The absence of MEPs after intense TMS pulses to the ipsilesional M1, and the reversible suppression of ongoing electromyographic (EMG) activity (indexed by CSP) demonstrate a weak modulation of subcortical systems by the ipsilesional left frontal cortex, but an inability to induce efficient descending volleys from those cortical locations to right hand and forearm muscles. Functional MRI recordings under grasping and finger tapping patterns involving the affected hand showed slight signs of subcortical recruitment, as compared to the unaffected hand and hemisphere, as well as the expected cortical activations. Conclusions: The potential sources of motor voluntary activity for the affected hand in absence of MEPs are discussed. We conclude that multimodal analysis may contribute to a more accurate prognosis of stroke patients.
Resumo:
Avalanche hazard maps of high accuracy are difficult to produce. For land-use planning and management purposes, a good knowledge of extreme run-out zones and frequencies of avalanches is required. In the present work, vegetation recognition (especially focused on Pinus uncinata trees) and dendrochronological techniques are used to characterize avalanches that have occurred in historical times, helping to determine both the extent of large or extreme avalanches and their occurrence in time. Vegetation was studied at the Canal del Roc Roig (eastern Pyrenees, Spain) avalanche path. The avalanches descending this path affect the railway that reaches the Vall de Núria resort and the run-up to the opposite slope. During winter 1996, two important avalanches affecting this path were well documented. These are compared with the results of the vegetation study, consisting of an inventory of flora, the recording of vegetation damages along eight transverse profiles at different altitudes on the path and a dendrochronological sampling campaign. The data obtained contributed to a characterization of the predominant snow accumulation in the starting zone, the 1996 avalanches and the range of frequencies of large avalanches. Also, traces of avalanches that increase the path mapped in the avalanche paths map published by the Institut Cartogràfic de Catalunya in 2000 were identified, improving the initial existing information.