A rationale for the optimisation by computer methods of the efficient use of metals and materials

The aim of the research project was to gain d complete and accurate accounting of the needs and deficiencies of materials selection and design data, with particular attention given to the feasibility of a computerised materials selection system that would include application analysis, property data and screening techniques. The project also investigates and integrates the three major aspects of materials resources, materials selection and materials recycling. Consideration of the materials resource base suggests that, though our discovery potential has increased, geologic availability is the ultimate determinant and several metals may well become scarce at the same time, thus compounding the problem of substitution. With around 2- to 20- million units of engineering materials data, the use of a computer is the only logical answer for scientific selection of materials. The system developed at Aston is used for data storage, mathematical computation and output. The system enables programs to be run in batch and interactive (on-line) mode. The program with modification can also handle such variables as quantity of mineral resources, energy cost of materials and depletion and utilisation rates of strateqic materials. The work also carries out an in-depth study of copper recycling in the U.K. and concludes that, somewhere in the region of 2 million tonnes of copper is missing from the recycling cycle. It also sets out guidelines on product design and conservation policies from the recyclability point of view

Intravenous Neck Injections in a Drug Abuser Resulting in Infection of a Laryngocele

A pyolaryngocele is an uncommon complication of a laryngocele that has become infected. We present a case of a pyolaryngocele that was probably due to repeated injections in the neck veins. The pathogenesis, clinical features and management are discussed in detail

Endovascular stent grafting versus open surgical repair of descending thoracic aortic aneurysms in low-risk patients: A multicenter comparative trial

ObjectiveResults are presented from the first completed multicenter trial directed at gaining approval from the US Food and Drug Administration of endovascular versus open surgical repair of descending thoracic aortic aneurysms.MethodsBetween September 1999 and May 2001, 140 patients with descending thoracic aneurysms were enrolled at 17 sites and evaluated for a Gore TAG Thoracic Endograft. An open surgical control cohort of 94 patients was identified by enrolling historical and concurrent subjects. Patients were assessed before treatment, at treatment, and at hospital discharge and returned for follow-up visits at 1 month, 6 months, and annually thereafter.ResultsOne hundred thirty-seven of 140 patients had successful implantation of the endograft. Perioperative mortality in the endograft versus open surgical control cohort was 2.1% (n = 3) versus 11.7% (n = 11, P < .001). Thirty-day analysis revealed a statistically significant lower incidence of the following complications in the endovascular cohort versus the surgical cohort: spinal cord ischemia (3% vs 14%), respiratory failure (4% vs 20%), and renal insufficiency (1% vs 13%). The endovascular group had a higher incidence of peripheral vascular complications (14% vs 4%). The mean lengths of intensive care unit stay (2.6 ± 14.6 vs 5.2 ± 7.2 days) and hospital stay (7.4 ± 17.7 vs 14.4 ± 12.8 days) were significantly shorter in the endovascular cohort. At 1 and 2 years’ follow-up, the incidence of endoleaks was 6% and 9%, respectively. Through 2 years of follow-up, there were 3 reinterventions in the endograft cohort and none in the open surgical control cohort. Kaplan–Meier analysis revealed no difference in overall mortality at 2 years.ConclusionsIn this multicenter study early outcomes with descending aortic endovascular stent grafting were very encouraging when compared with those of a well-matched surgical cohort. However, at 2 years’ follow-up, there is an incidence of endoleaks and reinterventions associated with endovascular versus open surgical repair. Continued vigilant surveillance of patients treated with an endograft is important

STUDY OF ACUTE TYPE A AORTIC DISSECTION PATIENTS WITH UNDILATED AORTAS

none15siopenFroehlich, Benjamin; Trimarchi, Santi; Bossone, Eduardo; Suzuki, Toru; Braverman, Alan; Kline-Rogers, Eva; Appoo, Jehangir; Di Eusanio, Marco; Gleason, Thomas; Abdul-Nour, Khaled; Lee, Teng; Montgomery, Daniel; Isselbacher, Eric; Nienaber, Christoph; Eagle, KimFroehlich, Benjamin; Trimarchi, Santi; Bossone, Eduardo; Suzuki, Toru; Braverman, Alan; Kline-Rogers, Eva; Appoo, Jehangir; Di Eusanio, Marco; Gleason, Thomas; Abdul-Nour, Khaled; Lee, Teng; Montgomery, Daniel; Isselbacher, Eric; Nienaber, Christoph; Eagle, Ki

AORTIC DISSECTION IN THE ELDERLY: COMPARING SEPTUAGENARIANS AND OCTOGENARIANS

none15siopenJabara, Justin; Peterson, Mark; Trimarchi, Santi; Myrmel, Truls; Reece, T. Brett; Bossone, Eduardo; Hutchison, Stuart; Gilon, Dan; Appoo, Jehangir; Di Eusanio, Marco; Montgomery, Daniel; Isselbacher, Eric; Nienaber, Christoph; Eagle, Kim; Patel, HimanshuJabara, Justin; Peterson, Mark; Trimarchi, Santi; Myrmel, Truls; Reece, T. Brett; Bossone, Eduardo; Hutchison, Stuart; Gilon, Dan; Appoo, Jehangir; Di Eusanio, Marco; Montgomery, Daniel; Isselbacher, Eric; Nienaber, Christoph; Eagle, Kim; Patel, Himansh

Patients with type A acute aortic dissection presenting with major brain injury: Should we operate on them?

none20siopenDi Eusanio, Marco*; Patel, Himanshu J.; Nienaber, Christoph A.; Montgomery, Daniel M.; Korach, Amit; Sundt, Thoralf M.; Devincentiis, Carlo; Voehringer, Matthias; Peterson, Mark D.; Myrmel, Truls; Folesani, Gianluca; Larsen, Magnus; Desai, Nimesh D.; Bavaria, Joseph E.; Appoo, Jehangir J.; Kieser, Teresa M.; Fattori, Rossella; Eagle, Kim; Di Bartolomeo, Roberto; Trimarchi, SantiDi Eusanio, Marco; Patel, Himanshu J.; Nienaber, Christoph A.; Montgomery, Daniel M.; Korach, Amit; Sundt, Thoralf M.; Devincentiis, Carlo; Voehringer, Matthias; Peterson, Mark D.; Myrmel, Truls; Folesani, Gianluca; Larsen, Magnus; Desai, Nimesh D.; Bavaria, Joseph E.; Appoo, Jehangir J.; Kieser, Teresa M.; Fattori, Rossella; Eagle, Kim; Di Bartolomeo, Roberto; Trimarchi, Sant

Human Blood Vessel–Derived Endothelial Progenitors for Endothelialization of Small Diameter Vascular Prosthesis

BACKGROUND:Coronary bypass graft failure as a result of acute thrombosis and intimal hyperplasia has been the major challenge in surgical procedures involving small-diameter vascular prosthesis. Coating synthetic grafts with patients' own endothelial cells has been suggested to improve the patency rate and overall success of bypass surgeries. METHODOLOGY/PRINCIPAL FINDINGS:We isolated endothelial progenitor cells (EPCs) from leftover pieces of human saphenous vein/mammary artery. We demonstrate that EPCs can be expanded to generate millions of cells under low-density culture conditions. Exposure to high-density conditions induces differentiation to endothelial cell phenotype. EPC-derived endothelial cells show expression of CD144high, CD31, and vWF. We then assessed the ability of differentiated endothelial cells to adhere and grow on small diameter expanded polytetrafluoroethylene (ePTFE) tubings. Since ePTFE tubings are highly hydrophobic, we optimized protocols to introduce hydrophilic groups on luminal surface of ePTFE tubings. We demonstrate here a stepwise protocol that involves introduction of hydrophilic moieties and coating with defined ECM components that support adhesion of endothelial cells, but not of blood platelets. CONCLUSION/SIGNIFICANCE:Our data confirms that endothelial progenitors obtained from adult human blood vessels can be expanded in vitro under xenoprotein-free conditions, for potential use in endothelialization of small diameter ePTFE grafts. These endothelialized grafts may represent a promising treatment strategy for improving the clinical outcome of small-caliber vascular grafts in cardiac bypass surgeries