• Journal of Society of Preventive Korean Medicine
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• v.12 no.3
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• pp.67-80
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• 2008

The pathobiologic process of arterial stenosis following balloon angioplasty continues to be an enigmatic problem in clinical settings. This study investigates the ability of demethoxycurcumin, a curcuminoid isolated from Radix Curcumae, to attenuate balloon injury-induced neointima(NI) formation in the rat carotid artery. It was found that demethoxycurcumin induced inducible heme oxygenase(HO-1) expression and inhibited dose-dependently cellular proliferation in rat vascular smooth muscle cells. Perivascular application of demethoxycurcumin immediately following injury significantly reduced NI area and NI thickness 2 weeks post-injury. Interestingly, treatment with tin-protoporphyrin IX, a HO inhibitor, reversed the effects of demethoxycurcumin on NI formation. These results implicate demethoxycurcumin as a potent new therapeutic agent that is capable of reducing post-angioplasty arterial stenosis through induction of the HO-1 expression.

• Applied Chemistry for Engineering
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• v.30 no.5
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• pp.586-590
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• 2019

The aim of this study was to fabricate a dextran polyelectrolyte multi-layer on a bare metal stent (BMS) and to evaluate bio-physical properties of the layer. Diethylaminoethyl-dextran (DEAE-D) as a polycation and dextran sulfate (DS) as a polyanion were successively coated on the bare metal stent by a well-known layer-by-layer procedure. The morphology of the stent surface and its cell adhesion were studied after each coating step by scanning electron microscopy. The stent showed more blotched and slightly rougher morphology after dextran-DS coating. The contact angle of the DEAE-DS group ($39.5{\pm}0.15^{\circ}$) was significantly higher than that of the BMS group ($45.16{\pm}0.08^{\circ}$), indicating the improvement of hydrophilic. The SMC proliferation inhibition in the DEAE-DS-coated stent group ($20.9{\pm}0.04%$) was stronger than that in the control group ($21.7{\pm}0.10%$ in DS-coated group only). The DEAE-DS coating is desired for stent coating materials with biocompatibility and anti-restenosis effect.

• Korean Journal of Bronchoesophagology
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• v.4 no.1
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• pp.27-34
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• 1998

Despite improvement in respiratory care, including use of low pressure and high volume cuffed tubes, tracheal stenosis remains a serious complication after a long-term tracheal intubation and tracheostomy. In such patients, tracheal resection and primary anastomosis is still considered ideal therapeutic modality. Between 1989 and 1997, we performed tracheal resections with end-to-end anastomosis on 14 patients with no operative mortality and some morbidity. Tracheal stenosis was caused by tracheostomy in nine patients, by endotracheal intubation in three patients and by thyroid carcinoma in two patients. The length of stenosis was various from 2cm to 4.5cm. All patient underwent segmental tracheal resection and primary anastomosis(14 patients) and additional procedures were cricoid cartilage reconstruction(2 patients), suprahyoid laryngeal release(3patients), carinal release technique(2 patients) and arytenoidectomy(2 patients). We have nine complications: granulona at anastomosis site in four patients, vocal cord palsy in two patients and restenosis, pneumonia, skin necrosis in each of those patients. The granuloma was removed by bronchoscopic forceps(4 patients). Vocal cord palsy was treated by arytenoidectorny(2 patients), restenosis by T-tube insertion, pneumonia by antibiotics and skin necrosis was treated by skin graft. We reviews our expenence of clinical features of tracheal stenosis and surgical treatment by tracheal one-to-end anastomosis with additional procedures to avoid postoperative complications for sucessful results.

• Journal of Sensor Science and Technology
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• v.30 no.3
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• pp.165-169
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• 2021

The objective of this study was to fabricate a novel hydrophobic stent for reducing restenosis by employing electron beam equipment. The stent was fabricated from a CoCr alloy tube by using a femtosecond laser and was treated with argon plasma. Subsequently, the stent's surface specification changed from hydrophilic to hydrophobic. Application of the electron beam offers several advantages such as a short processing time, whole surface reforming, and enhancement of material properties. As the surface of the stent was rendered hydrophobic, it can provide equivalent or enhanced mechanical properties and greater functionality with a higher radial force at the extended stent in a blood vessel. The obtained results corresponding to the mechanical properties indicate that the contact angle increased to approximately 130°, and the radial force increased to approximately 3 N. Furthermore, cell culture experiments were conducted for verifying whether cells were cultured on the surface-modified CoCr surface. Based on the obtained results, it is believed that an effective reduction in the restenosis of inserted vascular stents is possible.

• Journal of Yeungnam Medical Science
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• v.18 no.2
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• pp.215-225
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• 2001

Background: There are many evidences that inflammation is an important determinant of the development of atherosclerosis and one of the systemic markers of inflammation, C-reactive protein(CRP), is associated with extent of coronary artery disease and risk of coronary events. We assessed the time response of CRP response after coronary angioplasty and it's influence on the clinical restenosis in angina patients. Materials and Methods: Patients included 36 angina patients undergoing single vessel angioplasty. Levels of CRP were measured before and 12, 24, 48, and 72 hours after angioplasty. Clinical restenosis was assessed at 6 months after procedure. Results: Baseline CRP level was $0.30{\pm}0.01$ mg/dL in stable and $0.46{\pm}0.28$ mg/dL in unstable angina patients(p<0.05). After angioplasty, CRP level was increased with peak at 24 hour and persisted to 72 hours after angioplasty. At 24 hour after angioplasty, the magnitude of CRP change was $0.32{\pm}0.31$ mg/dL in stable and $0.79{\pm}0.73$ mg/dL in unstable angina patient(p<0.05). The change of CRP level was not associated with troponin-T after angioplasty. In unstable angina patients, clinical restenosis was developed in 8% of patients with low baseline CRP levels and in 50% of those with high baseline CRP levels more than 0.6 mg/dL(p<0.05). Conclusion: In unstable angina patients, inflammatory response is more increased than stable angina patients, and increased inflammatory response effects on the restenosis after coronary angioplasty.

• Progress in Medical Physics
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• v.20 no.3
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• pp.125-131
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• 2009

In this study, the paclitaxel eluting stent (PES) was prepared by coating a biliary stent with paclitaxel using various biopolymer such as poly (vinyl acetate) (PVAc), poly (lactic-co-glycolic acid) (PLGA), Silicone rubber for restenosis prevention in gastrointestinal disease by a dip-coating method. Drug contents of PES were increased as surface area of stent, concentration and molecular weight of coating polymer increase. In $^1H-NMR$ specta, we know that drug did not change by confirming specific peaks of paclitaxel in PES. As shown in SEM image, PES prepared using various biopolymer is coated clearly and regularly except Silicone rubber coating polymer. In in vitro cell cytotoxicity test, bare stent showed low cytotoxic effect against CT-26 colon carcinoma cell line on 3 day. However, PES coated with PLGA 502H showed the highest cytotoxicity because PLGA 502H is biodegradable polymer and has less molecular weight than other coating polymer. These results suggest that PES coated various biopolymer can be prevented restenosis in gastrointestinal disease.

• Biomolecules & Therapeutics
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• v.19 no.2
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• pp.187-194
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• 2011

Atherosclerosis and post-angiography restenosis are associated with intimal thickening and concomitant vascular smooth muscle cell (VSMC) proliferation. Obovatol, a major biphenolic component isolated from the Magnolia obovata leaf, is known to have anti-inflammatory and anti-tumor activities. The goal of the present study was to enhance the inhibitory effects of obovatol to improve its potential as a preventive or therapeutic agent in atherosclerosis and restenosis. Platelet-derived growth factor (PDGF)-BB-induced proliferation of rat aortic smooth muscle cells (RASMCs) was examined in the presence or absence of a newly synthesized obovatol derivative, OD78. The observed anti-proliferative effect of OD78 was further investigated by cell counting and [$^3H$]-thymidine incorporation assays. Treatment with 1-4 ${\mu}M$ OD78 dose-dependently inhibited the proliferation and DNA synthesis of 25 ng/ml PDGF-BB-stimulated RASMCs. Accordingly, OD78 blocked PDGF-BB-induced progression from the $G_0/G_1$ to S phase of the cell cycle in synchronized cells. OD78 decreased the expression levels of CDK4, cyclin E, and cyclin D1 proteins, as well as the phosphorylation of retinoblastoma protein and proliferating cell nuclear antigen; however, it did not change the CDK2 expression level. In addition, OD78 inhibited downregulation of the cyclin-dependent kinase inhibitor (CKI) $p27^{kip1}$. However, OD78 did not affect the CKI $p21^{cip1}$ or phosphorylation of early PDGF signaling pathway. These results suggest that OD78 may inhibit PDGF-BB-induced RASMC proliferation by perturbing cell cycle progression, potentially through $p27^{kip1}$ pathway activation. Consequently, OD78 may be developed as a potential anti-proliferative agent for the treatment of atherosclerosis and angioplasty restenosis.

• Journal of Chest Surgery
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• v.38 no.11 s.256
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• pp.795-798
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• 2005

The treatment of choice for post-intubation tracheal stenosis is partial tracheal resection and end-to-end ana-stomosis. The surgical treatment of tracheal restenosis that results from unsuccessful repair of post-intubation tracheal stenosis is not easy. Failed reoperation results in permanent tracheostomy and loss of voice. If the first operation fails, about $4\~6$ months of period for resolution of inflammatory reaction, edema, and fibrosis is needed. The exact evaluation of the patient's status is necessary and success rate of reoperation for the appropriate candidates is over $90\%$. We report the results of treatment in two cases of tracheal restenosis that resulted from unsuccessful repair of post-intubation tracheal stenosis with review of literatures.

• Journal of the Korean Society of Radiology
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• v.14 no.2
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• pp.179-191
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• 2020

The aim of this study was to investigate the predictors of major adverse cardiac events (MACE) in patients with drug-eluting balloon (DEB) for in-stent restenosis (ISR) lesion. Total of 257 patients who developed ISR on follow-up coronary angiography (66.1 ± 10.1years, 172 males) in Chonnam National University Hospital between October 2012 and January 2017 were enrolled. We divided the patients into two groups; group I (MACE group; n= 35) and group II (No MACE group; n= 222). A multivariate logistic regression analysis revealed that type IV ISR (HR=4.179, 95% C.I.=1.851-9.437 p= 0.001), lesion length > 25 mm (HR=8.773, 95% C.I.=1.898-40.546 p=0.005), number of ISR recurrence > 2 (HR=4.693, 95% C.I.=1.259-17.490 p= 0.021) were independent factors for MACE after DEB in ISR lesions.

• The Korean Journal of Nuclear Medicine
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• v.35 no.5
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• pp.293-300
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• 2001

The search for an ideal radioisotope for radiotherapy continues. As a generator-produced radioisotope emitting both beta and gamma rays with a short physical half-life of 16.9 hr, $^{188}Re$ is an excellent candidate for radiotherapy. Its applications Include the irradiation of coronary artery to prevent restenosis, treatment of rheumatoid arthritis, treatment of peritoneal effusion, palliation of metastatic bone pain, and treatment of liver cancer.