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Vascular Ring (vascular + ring)
Selected AbstractsOCCURRENCE OF VASCULAR RINGS IN EX-PRETERM TWINSJOURNAL OF PAEDIATRICS AND CHILD HEALTH, Issue 8 2004A Turner Dr No abstract is available for this article. [source] The Use of 3D Contrast-Enhanced CT Reconstructions to Project Images of Vascular Rings and Coarctation of the AortaECHOCARDIOGRAPHY, Issue 1 2009Thomas G. Di Sessa M.D. Background: Aortic arch and pulmonary artery anomalies make up a group of vascular structures that have complex three-dimensional (3D) shapes. Tortuosity as well as hypoplasia or atresia of segments of the aortic arch or pulmonary artery makes the conventional two-dimensional (2D) imaging difficult. Methods: Nine patients with native coarctation or recoarctation and 4 patients with a vascular ring had a CT scan as a part of their clinical evaluation. There were 7 males. The mean age was 11.7 years. (range 19 days to 29 years) The mean weight was 22.7 kg (range 3.3,139.0 kg). The dicom data from contrast CT scans were converted by the Amira software package into a 3D image. The areas of interest were selected. The images were then projected in 3D on a standard video monitor and could be rotated 360° in any dimension. Results: Adequate CT scans and 3D reconstructions were obtained in 12 of 13 patients. There were 85,1,044 slices obtained in the adequate studies. We could not reconstruct a 3D image from a patient's CT scan that had only 22 slices. The anatomy defined by 3D was compared to 2D CT imaging and confirmed by cardiac catheterization or direct visualization in the operating room in the 12 patients with adequate 3D reconstructions. In 5 of 12 patients, 3D reconstructions provided valuable spatial information not observed in the conventional 2D scans. Conclusion: We believe that 3D reconstruction of contrast-enhanced CT scans of these complex structures provides additional valuable information that is helpful in the decision-making process. [source] Cell wall composition of vascular and parenchyma tissues in broccoli stemsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 13 2003S Müller Abstract Broccoli stems can become tough and stringy owing to excessive development of the vascular ring. Thickened cell walls from the vascular ring were isolated and their composition was determined. They were derived principally from anatomically recognisable xylem vessels, fibres and tracheids but contained an assemblage of polysaccharides typical of primary cell walls. Their pectin content was particularly high and they contained only 6% lignin as estimated by solid state 13C NMR spectroscopy. They did not differ markedly in composition from parenchyma cell walls within the same stems. Thus, despite their thickness and anatomical appearance, these cell walls resembled the walls of non-woody cells in their polymer composition. Copyright © 2003 Society of Chemical Industry [source] Neuronal nitric oxide synthase does not contribute to the modulation of pulmonary vascular tone in fetal lambs with congenital diaphragmatic hernia (nNOS in CDH lambs),PEDIATRIC PULMONOLOGY, Issue 4 2008Anthony S. de Buys Roessingh MD Abstract Aim The aim of this study was to determine the presence of the neuronal nitric oxide synthase (nNOS) in near full-term lambs with congenital diaphragmatic hernia (CDH) and its role in the modulation of pulmonary vascular basal tone. Methods We surgically created diaphragmatic hernia on the 85th day of gestation. On the 135th, catheters were used to measure pulmonary pressure and blood flow. We tested the effects of 7-nitroindazole (7-NINA), a specific nNOS antagonist and of N -nitro- l -arginine (l -NNA), a nonspecific nitric oxide synthase antagonist. In vitro, we tested the effects of the same drugs on isolated pulmonary vessels. The presence of nNOS protein in the lungs was detected by Western blot analysis. Results Neither 7-NINA nor l -NNA modified pulmonary vascular basal tone in vivo. After l -NNA injection, acetylcholine (ACh) did not decrease significantly pulmonary vascular resistance (PVR). In vitro, l -NNA increased the cholinergic contractile-response elicited by electric field stimulation (EFS) of vascular rings from lambs with diaphragmatic hernia. Conclusion We conclude that nNOS protein is present in the lungs and pulmonary artery of near full-term lamb fetuses with diaphragmatic hernia, but that it does not contribute to the reduction of pulmonary vascular tone at birth. Pediatr Pulmonol. 2008; 43:313,321. © 2008 Wiley-Liss, Inc. [source] | ||||||||||