• Polymer(Korea)
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• v.28 no.5
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• pp.412-425
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• 2004

The influence of expandable graphite (EG) on flame retardancy and foaming properties of the NBR/GTR foams was studied. The foaming properties were similar to those of NBR/GTR foams without EG when the EG contents were 10$\~$30 phr. The LOI values were increased with the EG content. For cone-calorimeter test, the data showed the trend similar to that from experiment. When the composition ratios of the compounds of NBR/GTR were 100$\~$0/80$\~$20 (w/w), and the EG contents were 10$\~$30 phr, we obtained high flame retardancy foams with low heat release rate (HRR), total heat release (THR), effective heat of combustion (EHC) and carbon monoxide yield (COY). The smoke density is similar to CO yield values obtained by the cone-calorimeter test. TGA analysis also showed the results approximately similar to those from the LOI and cone-calorimeter experiments.

• Korean Circulation Journal
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• v.54 no.8
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• pp.499-512
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• 2024

Background and Objectives: Arterial dissection during endovascular therapy rarely occurs but can be lethal. A fabric-based covered graft stents yield poor clinical outcomes. A novel balloon-expandable stent with biodegradable film graft for overcoming these issues was evaluated in a rabbit iliac artery model. Method: Eighteen rabbits with iliac artery dissections were induced by balloon over-inflation on angiography (Ellis type 2 or 3) and treated using the test device (3.0×24 mm). Subsequently, survived twelve animals underwent histologic examinations and micro-computed tomography (CT) at 0, 2, 4, and 8 weeks and 3, 6, 9, and 12 months and angiography at one-year. Results: There were no adverse cardiovascular events during the one-year. Early-stage histologic examination revealed complete sealing of disrupted vessels by the device, exhibiting mural hematoma, peri-stent red thrombi, and dense infiltration of inflammatory cells. Mid- and long-term histologic examination showed patent stents with neointimal hyperplasia over the stents (% area stenosis: 11.8 at 2 weeks, 26.1 at 1 month, 29.7 at 3 months, 49.2 at 9 months, and 51.0 at 1 year), along with mild peri-strut inflammatory response (Grade: 1-2 at mid-term and 0-1 at long-term). The graft film became scarcely visible after six months. Both CT and angiography revealed no instances of thrombotic occlusion or in-stent restenosis (% diameter stenosis: 5.7 at 2 weeks, 12.3 at 1 month, 14.2 at 3 months, 25.1 at 9 months, and 26.6 at 1 year). Conclusions: The novel balloon-expandable stent with a biodegradable film graft demonstrates feasibility in managing severe artery dissection and preventing lethal vascular events in animal model.

• Clinical Endoscopy
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• v.55 no.1
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• pp.150-155
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• 2022

We reviewed 7 patients with unsuccessful endoscopic hemostasis using covered self-expandable metal stent (CSEMS) placement for post-endoscopic sphincterotomy (ES) bleeding. ES with a medium incision was performed in 6 and with a large incision in 1 patient. All but 1 of them (86%) showed delayed bleeding, warranting second endoscopic therapies followed by CSEMS placement 1-5 days after the initial ES. Subsequent CSEMS placement did not achieve complete hemostasis in any of the patients. Lateral-side incision lines (3 or 9 o'clock) had more frequent bleeding points (71%) than oral-side incision lines (11-12 o'clock; 29%). Additional endoscopic hemostatic procedures with hemostatic forceps, hypertonic saline epinephrine, or hemoclip achieved excellent hemostasis, resulting in complete hemostasis in all patients. These experiences provide an alert: CSEMS placement is not an ultimate treatment for post-ES bleeding, despite its effectiveness. The lateral-side of the incision line, as well as the oral-most side, should be carefully examined for bleeding points, even after the CSEMS placement.

• Clinical Endoscopy
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• v.57 no.5
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• pp.628-636
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• 2024

Background/Aims: Advanced pancreatic and biliary tract cancers can invade the duodenum and cause duodenal hemorrhagic stenosis. This study aimed to evaluate the efficacy of covered self-expandable metal stents in the treatment of cancer-related duodenal hemorrhage with stenosis. Methods: Between January 2014 and December 2016, metal stents were placed in 51 patients with duodenal stenosis. Among these patients, a self-expandable covered metal stent was endoscopically placed in 10 patients with hemorrhagic duodenal stenosis caused by pancreatobiliary cancer progression. We retrospectively analyzed the therapeutic efficacy of the stents by evaluating the technical and clinical success rates based on successful stent placement, degree of oral intake, hemostasis, stent patency, and overall survival. Results: The technical and clinical success rates were 100%. All 10 patients achieved a gastric outlet obstruction scoring system score of three within two weeks after the procedure and had no recurrence of melena. The median stent patency duration and overall survival after stent placement were 52 days (range, 20-220 days) and 66.5 days (range, 31-220 days), respectively. Conclusions: Endoscopic placement of a covered metal stent for hemorrhagic duodenal stenosis associated with pancreatic or biliary tract cancer resulted in duodenal hemostasis, recanalization, and improved quality of life.

• Journal of Korea Foundry Society
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• v.18 no.4
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• pp.325-333
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• 1998

• Proceedings of the Korean Fiber Society Conference
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• 1993.06a
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• pp.45-46
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• 1993

• Proceedings of the Korean Ceranic Society Conference
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• 2003.10a
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• pp.137.2-137
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• 2003

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2018.11a
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• pp.392-393
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• 2018

• Clinical Endoscopy
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• v.56 no.6
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• pp.741-743
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• 2023

• Clinical Endoscopy
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• v.55 no.3
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• pp.369-371
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• 2022