994 resultados para Apical bud


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OBJECTIVES: Transapical transcatheter valve procedures are performed through a left minithoracotomy and require apical sutures to seal the apical access site. The use of large-calibre devices compromises any attempt to fully perform the procedure with a thoracoscopic approach or percutaneously. We report our preliminary experience in animals with a new sutureless self-expandable apical occluder, engineered to perform transapical access site closure in a minimally invasive setting with large-size introducer sheaths. METHODS: The apical occluder with extendable waist was implanted in six young pigs during an acute animal study. Under general anaesthesia, animals (mean weight: 62 ± 8 kg) received full heparinization (heparin: 100 UI/kg; activated clotting time above 250 s). Through a median sternotomy, a 21-Fr Certitude? introducer sheath (outer diameter: 25 Fr) was placed over the wire into the cardiac apex. The delivery catheter carrying the constrained apical plug was inserted into the sheath and deployed under fluoroscopic control, whereas the Certitude? was retrieved. After protamine infusion, we observed and recorded the 1-h bleeding with standard haemodynamic parameters. Animals were sacrificed, and hearts analysed. RESULTS: Six apical closure devices were successfully introduced and deployed in six pig hearts through large-size apical sheaths at first attempt. In all animals, the plugs guaranteed immediate apical sealing and traces of blood were collected in the pericardium during the 1-h observational period (mean of 16 ± 3.4 ml of blood loss per animal). Haemodynamic parameters remained stable during the entire study period and no plug dislodgement was detected with normal systemic blood pressure (mean arterial mean blood pressure: 65 ± 7 mmHg). Post-mortem analysis confirmed the full deployment and good fixation of all plugs, without macroscopic damages to the surrounding myocardium. CONCLUSIONS: This sutureless self-expandable apical occluder is a simple device capable of sealing large-size apical access sites (20-35 Fr) in an acute animal study. This approach is a step further towards less invasive transapical valve procedures in the clinical setting, and further animal tests will be performed to confirm the long-term efficacy and safety of this device.

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During transapical transcatheter aortic valve replacement (TA-TAVR), the apical closure remains a challenge for the surgeon, having the risk for ventricular tear and massive bleeding. Apical closure devices are already under clinical evaluation, but only a few can lead to a full percutaneous TA-TAVR. We describe the successful use of a 9-mm myocardial occluder (ventricular septal defect occluder) that was used to seal the apex after a standard TA-TAVR (using the Sapien XT 23-mm transcatheter valve and the Ascendra + delivery system). The placement of the nonmodified myocardial occluder was performed through the Ascendra + delivery system, with a very small amount of blood loss and an acceptable sealing of the apical tear. This approach is feasible and represents a further step toward true-percutaneous transapical heart valve procedures. Modified apical occluders are under evaluation in animal models.

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The majority of transcatheter aortic valve implantations, structural heart procedures and the newly developed transcatheter mitral valve repair and replacement are traditionally performed either through a transfemoral or a transapical access site, depending on the presence of severe peripheral vascular disease or anatomic limitations. The transapical approach, which carries specific advantages related to its antegrade nature and the short distance between the introduction site and the cardiac target, is traditionally performed through a left anterolateral mini-thoracotomy and requires rib retractors, soft tissue retractors and reinforced apical sutures to secure, at first, the left ventricular apex for the introduction of the stent-valve delivery systems and then to seal the access site at the end of the procedure. However, despite the advent of low-profile apical sheaths and newly designed delivery systems, the apical approach represents a challenge for the surgeon, as it has the risk of apical tear, life-threatening apical bleeding, myocardial damage, coronary damage and infections. Last but not least, the use of large-calibre stent-valve delivery systems and devices through standard mini-thoracotomies compromises any attempt to perform transapical transcatheter structural heart procedures entirely percutaneously, as happens with the transfemoral access site, or via a thoracoscopic or a miniaturised video-assisted percutaneous technique. During the past few years, prototypes of apical access and closure devices for transapical heart valve procedures have been developed and tested to make this standardised successful procedure easier. Some of them represent an important step towards the development of truly percutaneous transcatheter transapical heart valve procedures in the clinical setting.

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The influence of voltage on the conductance of toad skin was studied to identify the time course of the activation/deactivation dynamics of voltage-dependent Cl- channels located in the apical membrane of mitochondrion-rich cells in this tissue. Positive apical voltage induced an important conductance inhibition which took a few seconds to fully develop and was instantaneously released by pulse inversion to negative voltage, indicating a short-duration memory of the inhibiting factors. Sinusoidal stimulation at 23.4 mM [Cl-] showed hysteresis in the current versus voltage curves, even at very low frequency, suggesting that the rate of voltage application was also relevant for the inhibition/releasing effect to develop. We conclude that the voltage modulation of apical Cl- permeability is essentially a fast process and the apparent slow components of activation/deactivation obtained in the whole skin are a consequence of a gradual voltage build-up across the apical membrane due to voltage sharing between apical and basolateral membranes

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Tesis (Especialidad en Endodoncia) UANL, 2010.

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Tesis (Maestría en Ciencias Odontológicas con Especialidad en Endodoncia) UANL, 2012.

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Tesis (Maestría en Ciencias Odontológicas con Especialidad en Endodoncia) UANL, 2011.

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Tesis (Maestría en Ciencias Odontológicas con orientación en Endodoncia) UANL, 2014.

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Moringa oleifera is becoming increasingly popular as an industrial crop due to its multitude of useful attributes as water purifier, nutritional supplement and biofuel feedstock. Given its tolerance to sub-optimal growing conditions, most of the current and anticipated cultivation areas are in medium to low rainfall areas. This study aimed to assess the effect of various irrigation levels on floral initiation, flowering and fruit set. Three treatments namely, a 900 mm (900IT), 600 mm (600IT) and 300 mm (300IT) per annum irrigation treatment were administered through drip irrigation, simulating three total annual rainfall amounts. Individual inflorescences from each treatment were tagged during floral initiation and monitored throughout until fruit set. Flower bud initiation was highest at the 300IT and lowest at the 900IT for two consecutive growing seasons. Fruit set on the other hand, decreased with the decrease in irrigation treatment. Floral abortion, reduced pollen viability as well as moisture stress in the style were contributing factors to the reduction in fruiting/yield observed at the 300IT. Moderate water stress prior to floral initiation could stimulate flower initiation, however, this should be followed by sufficient irrigation to ensure good pollination, fruit set and yield.

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La Necrosi Apical Bruna (BAN, brown apical necrosis, segons les sigles en anglès) Es va detectar per primer cop l’any 1997 a Extremadura degut a la severa caiguda de fruits. Avui dia la malaltia és present a quasi totes les zones productores de la mediterrània. Els símptomes difereixen dels provocats per Xanthomonas arboricola pv. juglandis i Gnomonia leptsostyla.. S’observa que els fruits afectats presenten una taca bruna a la zona apical i necrosi dels teixits interiors. El grup de Patologia Vegetal de la Universitat de Girona participa i dirigeix la tasca sobre l’etiologia de la BAN dins la xarxa europea d’investigació en bacteris patògens de fruiters ,COST873. Hi ha una certa controvèrsia en la definició dels símptomes i agents causals. Tots els grups coincideixen en afirmar que es tracta d’una malaltia complexa amb diferents organismes implicats

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Não é novidade que o paradigma vigente baseia-se na Internet, em que cada vez mais aplicações mudam o seu modelo de negócio relativamente a licenciamento e manutenção, para passar a oferecer ao utilizador final uma aplicação mais acessível no que concerne a licenciamento e custos de manutenção, já que as aplicações se encontram distribuídas eliminando os custos de capitais e operacionais inerentes a uma arquitetura centralizada. Com a disseminação das Interfaces de Programação de Aplicações (Application Programming Interfaces – API) baseadas na Internet, os programadores passaram a poder desenvolver aplicações que utilizam funcionalidades disponibilizadas por terceiros, sem terem que as programar de raiz. Neste conceito, a API das aplicações Google® permitem a distribuição de aplicações a um mercado muito vasto e a integração com ferramentas de produtividade, sendo uma oportunidade para a difusão de ideias e conceitos. Este trabalho descreve o processo de conceção e implementação de uma plataforma, usando as tecnologias HTML5, Javascript, PHP e MySQL com integração com ®Google Apps, com o objetivo de permitir ao utilizador a preparação de orçamentos, desde o cálculo de preços de custo compostos, preparação dos preços de venda, elaboração do caderno de encargos e respetivo cronograma.