515 research outputs found
How Much Evidence is Needed for the Introduction of New Technologies Into Clinical Practice in Vascular Surgery?
Three Drug Indications for Patients with Peripheral Arterial Disease Bite the Dust: Report from the American Heart Association Meeting 2007 in Orlando
Investigations on the Altered Plane as a Creative Element in the Visual Arts
This is primarily a report of personal investigation by the author though some relevant references are used.
The work is divided into two parts representing two conceptions of the altered image bearing plane.
Essential to both conceptions is the use of the image bearing plane for its creative potential, rather than as a passive image support.
The modulated plane as image producer is discussed in part one with reference to its use for literal imagery and self derived imagery. Also mentioned are related printmaking, papermaking, plastic forming, and additive low relief techniques.
Part two deals with spatially related planes as image supports and as sources of imagery. Topics covered are angular intersecting planes, the split plane, and superimposed planes.
Also included are discussions on the author\u27s approach to materials which emphasized the use of all materials in a manner harmonious with the physical structure of the individual material.
A brief overview of modern art tendencies in relation to the image bearing surface is included.
As the third dimension is employed in all graphic works mentioned, the relationship between two and three dimensional artistic displines is explored.
A case is made for the acceptance of these works as having a natural aesthetic base.
Several works and the techniques of their production are described.
Four color and six black and white illustrations are included.
90 pages
Investigations on the Altered Plane as a Creative Element in the Visual Arts
This is primarily a report of personal investigation by the author though some relevant references are used.
The work is divided into two parts representing two conceptions of the altered image bearing plane.
Essential to both conceptions is the use of the image bearing plane for its creative potential, rather than as a passive image support.
The modulated plane as image producer is discussed in part one with reference to its use for literal imagery and self derived imagery. Also mentioned are related printmaking, papermaking, plastic forming, and additive low relief techniques.
Part two deals with spatially related planes as image supports and as sources of imagery. Topics covered are angular intersecting planes, the split plane, and superimposed planes.
Also included are discussions on the author\u27s approach to materials which emphasized the use of all materials in a manner harmonious with the physical structure of the individual material.
A brief overview of modern art tendencies in relation to the image bearing surface is included.
As the third dimension is employed in all graphic works mentioned, the relationship between two and three dimensional artistic displines is explored.
A case is made for the acceptance of these works as having a natural aesthetic base.
Several works and the techniques of their production are described.
Four color and six black and white illustrations are included.
90 pages
Observations from the IMPROVE Trial Concerning the Clinical Care of Patients with Ruptured Abdominal Aortic Aneurysm
The Rupture Rate of Large Abdominal Aortic Aneurysms: Is This Modified by Anatomic Suitability for Endovascular Repair?
Prostaglandin e2 receptors in abdominal aortic aneurysm and human aortic smooth muscle cells
AbstractBackgroundProstaglandin (PG) E2 (PGE2) appears to have a role in stimulating production of interleukin-6 (IL-6) and apoptosis of smooth muscle cells in diseased aortic tissue. These actions are mediated by cellular receptors for PGE2 EP receptors.ObjectiveThis study was undertaken to identify EP receptors associated with production of IL-6 by aortic explants.MethodsBiopsy specimens of abdominal aortic aneurysm were used for explant culture and preparation of messenger RNA. The presence of EP1, EP2, EP3, and EP4 receptors in tissue and cells was investigated with reverse-transcriptase polymerase chain reaction. IL-6 and cyclic adenosine monophosphate were measured with an enzyme-linked immunosorbent assay.ResultsPGE2 or 11-deoxy-PGE1 (EP 2/3/4 agonist) reversed partially the indomethacin suppression of IL-6 secretion from explant cultures, whereas butaprost (EP2 receptor agonist) and sulprostone (EP 1/3 receptor agonist) had no effect. Aortic biopsy specimens expressed EP2, EP3-III, and EP4 receptors. Aortic smooth muscle cells expressed EP2 receptor and four variants of EP3 receptor, ie, EP3-Ib, EP3-II, EP3-III, and EP3-IV, but PGE2 did not stimulate secretion of IL-6. In contrast, PGE2 or 11-deoxy-PGE1 stimulated secretion of IL-6 from aortic macrophages.ConclusionsIn aortic explants, PGE2 stimulates IL-6 secretion by activation of EP4 receptors, present in macrophages
Dilatation of saphenous vein grafts by nitric oxide
Objectives:To investigate firstly whether flow-dependent vasodilation is maintained in vein grafts, and secondly whether nitric oxide donors dilate vein grafts to improve the flow through graft stenoses.Design, materials and methods:The vasodilatation of mature patent vein grafts, in response to reactive hyperaemia and glyceryl trinitrate (GTN), was assessed by the change in external diameter using duplex ultrasonography. The severity (ratio of proximal systolic velocity, V1, to peak systolic velocity at the stenosis, V2, of vein graft stenoses was determined by duplex ultrasonography before and after 24 h of local application of GTN patches.Results:In post-occlusion hyperaemia the diameter of patent distal vein grafts (n = 7) increased to a maximum of 112±1.9% of resting diameter after 2 min, p = 0.026. The diameter increased further to 117±2.5% of the resting value 5 min after oral GTN (n = 5), p = 0.007. The velocity ratio, V2/V1, through graft stenoses (n = 6) decreased by 20 ± 5% after application of GTN patches, principally as a result of reduction in V2, mean difference 0.8, p = 0.15. The changes in response to GTN were more evident for proximal than distal vein graft stenoses.Conclusion:Flow-induced vasodilatation responses, which have been attributed to the endothelial release of nitric oxide, are maintained in patent vein grafts: the grafts dilate even further in response to GTN. The application of GTN patches close to a vein graft stenosis appears to reduce the velocity ratio through vein graft stenoses. GTN patches might be used to reduce the risk of graft occlusion when there is a delay between the detection and the treatment of haemodynamically significant graft stenoses
Meta-analysis of individual-patient data from EVAR-1, DREAM, OVER and ACE trials comparing outcomes of endovascular or open repair for abdominal aortic aneurysm over 5 years
Background: The erosion of the early mortality advantage of elective endovascular aneurysm repair (EVAR) compared with open repair of abdominal aortic aneurysm remains without a satisfactory explanation. Methods: An individual-patient data meta-analysis of four multicentre randomized trials of EVAR versus open repair was conducted to a prespecified analysis plan, reporting on mortality, aneurysm-related mortality and reintervention. Results: The analysis included 2783 patients, with 14 245 person-years of follow-up (median 5·5 years). Early (0–6 months after randomization) mortality was lower in the EVAR groups (46 of 1393 versus 73 of 1390 deaths; pooled hazard ratio 0·61, 95 per cent c.i. 0·42 to 0·89; P = 0·010), primarily because 30-day operative mortality was lower in the EVAR groups (16 deaths versus 40 for open repair; pooled odds ratio 0·40, 95 per cent c.i. 0·22 to 0·74). Later (within 3 years) the survival curves converged, remaining converged to 8 years. Beyond 3 years, aneurysm-related mortality was significantly higher in the EVAR groups (19 deaths versus 3 for open repair; pooled hazard ratio 5·16, 1·49 to 17·89; P = 0·010). Patients with moderate renal dysfunction or previous coronary artery disease had no early survival advantage under EVAR. Those with peripheral artery disease had lower mortality under open repair (39 deaths versus 62 for EVAR; P = 0·022) in the period from 6 months to 4 years after randomization. Conclusion: The early survival advantage in the EVAR group, and its subsequent erosion, were confirmed. Over 5 years, patients of marginal fitness had no early survival advantage from EVAR compared with open repair. Aneurysm-related mortality and patients with low ankle : brachial pressure index contributed to the erosion of the early survival advantage for the EVAR group. Trial registration numbers: EVAR-1, ISRCTN55703451; DREAM (Dutch Randomized Endovascular Aneurysm Management), NCT00421330; ACE (Anévrysme de l'aorte abdominale, Chirurgie versus Endoprothèse), NCT00224718; OVER (Open Versus Endovascular Repair Trial for Abdominal Aortic Aneurysms), NCT00094575.</p
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