Cubic boron nitride (c-BN) films were deposited by an unbalanced magnetron sputtering method. A (100) Si wafer with a nanocrystalline diamond thin film as a surface coating layer or that without it ...was used as a substrate. The target power was varied from 100 to 400 W. A boron nitride target was used, which was connected to a radio frequency power supply. High frequency power connected to a substrate holder was used for self-biasing. The deposition pressure was 0.27 MPa with a flow of Ar (18 sccm) — N
2
(2 sccm) mixed gas. The existence of threshold bias voltages for c-BN formation and resputtering were observed irrespective of target power. The bias voltage window for c-BN formation broadened with increased target power. The deposition rate decreased with enhanced bias voltage and decreased target power. Residual stresses of the films did not vary noticeably with target power within the target power range of c-BN formation. A parameter space for c-BN formation according to the target power and the bias voltage, as two variables, was suggested.
Multiple overlapping drug-eluting stents have increasingly been used to treat diffuse coronary disease, but the safety and efficacy of this approach remains unclear. We assayed the clinical and ...angiographic outcomes after placement of “full metal jacket” stents (stented length ≥60 mm) in 347 consecutive patients (352 lesions) with very long de novo coronary lesions. Mean age was 61.0 ± 10.1 years, and the mean stented length was 71.9 ± 13.7 mm. The procedural success rate was 97.7%. Major in-hospital complications (1 death, 2 cases of acute stent thrombosis) occurred in 3 patients (0.7%). Angiographic follow-up data, obtained for 230 (234 lesions) of the 328 eligible patients (70.1%), showed that the restenosis rate was 13.7%. Multivariate analysis found that the reference artery diameter (odds ratio 0.05, 95% confidence interval CI 0.01 to 0.33, p = 0.002) and the use of Taxus stents (odds ratio 2.88, 95% CI 1.03 to 8.04, p = 0.043) were significant predictors of restenosis. During follow-up (16.6 ± 6.9 months), 9 deaths (6 cardiac and 3 noncardiac), 1 nonfatal myocardial infarction, and 13 target lesion revascularizations occurred. The cumulative probability of survival without major adverse cardiac events (cardiac death, Q-wave myocardial infarction, and target lesion revascularization) was 95.4 ± 1.1% and 91.4 ± 2.1% at 1 and 2 years, respectively. Left ventricular dysfunction (ejection fraction <45%) was the only predictor of stent thrombosis (hazard ratio 18.24, 95% CI 1.65 to 201.19, p = 0.018) and cardiac death/Q-wave myocardial infarction (hazard ratio 5.37, 95% CI 1.28 to 22.49, p = 0.021). In conclusion, full metal jacket drug-eluting stents may be a safe and effective method to treat diffuse coronary disease and may be a useful treatment option for complex long lesions.
The long-term natural history of acquired malapposition continues to be the subject of debate.
Using volumetric intravascular ultrasound analyses, we evaluated serial (poststenting, 6-month, and ...2-year follow-up) changes in drug-eluting stent-treated vascular segments with acquired malapposition. External elastic membrane, stent, lumen, malapposition, and peristent plaque+media (P+M=external elastic membrane -stent- malapposition) areas were measured; and volumes were calculated and divided by stent length (normalized volume). Among 250 lesions in which complete serial intravascular ultrasound data were available, stent malapposition was identified in 19 lesions (7.6%) at 6 months, and an additional 13 malapposition lesions were newly detected at 2 years (5.2%). Because no malapposition sites resolved, the malapposition rate at 2 years was 12.8%. Malapposition areas and volumes were correlated to the increases in external elastic membrane (positive remodeling) throughout the study period, from immediately after stenting to 6 months and from 6 months to 2 years, both in the group that developed malapposition at 6 months and in the group that developed malapposition at 2 years. Clinical follow-up beyond the 2 year intravascular ultrasound study was done in all patients. Overall, there were 2 cardiac deaths and 1 noncardiac death. Two patients presented with acute myocardial infarction associated with very late stent thrombosis (1 definite stent thrombosis, 1 probable stent thrombosis). Three patients underwent repeat revascularization owing to in-stent restenosis developed after the 2-year follow-up.
Expansive vascular remodeling may play a role in the development and dynamic progression of acquired drug-eluting stent malapposition, not only during the first 6 months after implantation but thereafter.
ABSTRACTReactive oxygen species (ROS) are known aggravating factors for airway inflammation in asthma. Glutathione S-transferases (GSTs) detoxify ROS and toxic compounds in environmental exposures. ...However, little is known about the regulation of GST and expression of GST subtypes in asthma. The aim of this study was to evaluate how GSTs are regulated in asthma. We observed total GST activity and expression of GST subtypes in murine asthma models and GST expressions in induced sputum cells of asthmatics. Total GST activity was increased in BAL fluids of OVA-treated murine asthma model. GSTP and GSTA are highly expressed in peribronchiolar mononuclear inflammatory cells and epithelial cells in OVA-treated mice. GSTM are expressed in epithelial cells in both OVA and PBS-treated groups. GSTP1 mRNA expression was increased in the lung of OVA-treated mice compared with PBS-treated mice. GSTA1, GSTM1, and GSTT1 mRNA expressions were not different between both groups. GSTA1 mRNA expression was increased in induced sputum cells of asthmatics compared with healthy controls. GSTP1, GSTM1, and GSTT1 mRNA expressions were not different between asthmatics and healthy controls. In asthmatics, GSTP1 and GSTA1 mRNA expressions were higher in induced sputum cells of asthmatics with PC20 ≤ 4 mg/ml than those with PC20 > 4 mg/ml. GSTM1 and GSTT1 mRNA expressions were not different between two groups. These findings suggest that GSTs are upregulated in the airways of asthmatics in response to increased oxidative stress. GSTP and GSTA are thought to play an important role in protecting the airways of asthmatics compared with GSTM and GSTT.
최근 들어 늘어나고 있는 도시형 화재 사고와 건축 외장재에 따른 화재 피해 사례의 증가에 따라 난연처리기술의 중요성이 부각되고 있다. 특히, 목재를 기반으로 한 건축재료의 활용에 있어서 난연처리기술은 더욱 중요하게 평가되고 있다. Intumescent 시스템은 비할로겐계 난연처리기술의 하나로, 발포와 탄화층 형성을 통하여 난연성을 구현하는 시스템이다. 본 ...연구에서는 Intumescent 시스템을 적용하기 위해 Ethylene vinyl acetate (EVA)를 매트릭스로 채용하여 복합재료를 제조하였다. Intumescent 시스템의 난연특성을 강화하기 위해 나노클레이를 함께 적용하였다. Intumescent 시스템과 나노클레이 기술을 함께 적용한 복합재료를 시트상의 시험편으로 가공한 후, 이를 활용하여 표면의 난연특성이 강화된 새로운 구조의 교호집성재를 제작하였다. Intumescent 시스템을 적용한 복합재료의 연소특성 평가에서 최대 열방출량이 효과적으로 감소되는 것을 확인할 수 있었다. 표면에 부착된 구조에 따라 CLT는 두 단계에 걸친 연소현상이 발생했다. 또한, 심부 연소 과정에서 최대 열방출률이 크게 감소하는 경향을 확인할 수 있었다. 이러한 특성은 목재의 연소과정에 있어 연소 확산지연효과가 있을 것으로 판단된다. 표면단판에 대한 난연처리기술 및 복합재료 적용 최적화 기술을 통해 보다 화재특성이 개선된 CLT 구조체 개발이 가능할 것으로 기대된다.
Recently, the importance of flame retardation treatment technology has been emphasized due to the increase in urban fire accidents and fire damage incidents caused by building exterior materials. Particularly, in the utilization of wood-based building materials, the flame retarding treatment technology is more importantly evaluated. An Intumescent system is one of the non-halogen flame retardant treatment technologies and is a system that realizes flame retardancy through foaming and carbonization layer formation. To apply the Intumescent system, composite material was prepared by using Ethylene vinyl acetate (EVA) as a matrix. To enhance the flame retardant properties of the Intumescent system, a nano-clay was applied together. Composite materials with Intumescent system and nano - clay technology were processed into sheet - like test specimens, and then a new structure of cross laminated timber with improved flame retardant properties was fabricated. In the evaluation of combustion characteristics of composite materials using Intumescent system, it was confirmed that the maximum heat emission was reduced efficiently. Depending on the structure attached to the surface, the CLT had two stages of combustion. Also, it was confirmed that the maximum calorific value decreased significantly during the deep burning process. These characteristics are expected to have a delayed combustion diffusion effect in the combustion process of CLT. In order to improve the performance, the flame retardation treatment technique for the surface veneer and the optimization technique of the application of the composite material are required. It is expected that it will be possible to develop a CLT structure with improved fire characteristics.
Objectives This study sought to evaluate the long-term safety and effectiveness of percutaneous coronary intervention (PCI), as compared with coronary artery bypass grafting (CABG), for unprotected ...left main coronary artery (LMCA) disease. Background Data on the long-term (beyond 5-year) comparative results of treatment of unprotected LMCA disease with stent implantation or CABG are limited. Methods We performed a 10-year clinical follow-up of 350 patients with unprotected LMCA disease who underwent PCI with bare-metal stents (BMS) (n = 100) or CABG (n = 250) from January 1995 to April 1999, and 5-year clinical follow-up of 395 patients with unprotected LMCA disease who underwent PCI with drug-eluting stents (DES) (n = 176) or CABG (n = 219) from January 2003 to May 2004. The primary safety end points were all-cause mortality and the composite of death, Q-wave myocardial infarction (MI), or stroke, and the primary efficacy end point was target vessel revascularization (TVR). Results In the 10-year follow-up cohort of BMS and concurrent CABG, the adjusted risks of death (hazard ratio HR: 0.81; 95% confidence interval CI: 0.44 to 1.50; p = 0.50) and the composite of death, Q-wave MI, or stroke (HR: 0.92; 95% CI: 0.55 to 1.53; p = 0.74) were similar between the 2 groups. The rate of TVR was significantly higher in the group that received BMS (HR: 10.34; 95% CI: 4.61 to 23.18; p < 0.001). In the 5-year follow-up cohort of DES and concurrent CABG, there was no significant difference in the adjusted risk of death (HR: 0.83; 95% CI: 0.34 to 2.07; p = 0.70) or the risk of the composite outcome (HR: 0.91; 95% CI: 0.45 to 1.83; p = 0.79). The rates of TVR were also higher in the DES group than the CABG group (HR: 6.22; 95% CI: 2.26 to 17.14; p < 0.001). Conclusions For the treatment of unprotected LMCA disease, PCI with stent implantation showed similar long-term mortality and rates of death, Q-wave MI, or stroke. However, stenting, even with DES, was associated with higher rates of repeat revascularization than was CABG.
Takayasu's arteritis is a chronic inflammatory disorder that mainly involves medium to large sized arteries. Although it affects coronary and pulmonary arteries occasionally, physicians should ...consider the possibility of involvement of coronary or pulmonary arteries in patients with Takayasu's arteritis with chest pain or exertional dyspnoea. We report a case of Takayasu's arteritis who presented with exertional dyspnoea and generalised oedema due to severe bilateral pulmonary and left main coronary arterial stenoses. The patient was successfully treated by a one-stage percutaneous transluminal balloon angioplasty and stent implantation of the involved left main coronary and pulmonary arteries. The endovascular treatment may be one of the treatment options for the stenotic vascular lesions in patients with Takayasu's arteritis.
To evaluate the impact of ad hoc percutaneous coronary intervention (PCI) which combines coronary angioplasty and PCI in the same procedure in the era of drug-eluting stents (DES).
From the IRIS-DES ...registry, 4,738 angina patients treated using PCI with DES were enrolled. The 18-month outcomes were compared between ad hoc and non-ad hoc groups after adjustment using inverse-probability-of-treatment weighting. Ad hoc PCI was performed in 3,562 (75.2%) patients. The ad hoc PCI group had less extensive coronary disease and received fewer stents. The incidence of major adverse cardiac or cerebrovascular events, consisting of death, myocardial infarction (MI), stroke, and repeat revascularisation, did not differ between the ad hoc and the non-ad hoc groups (8.3% vs. 7.6%; adjusted hazard ratio aHR of ad hoc PCI, 1.22; 95% confidence interval CI: 0.91 to 1.63; p=0.18). The individual endpoints of death (2.0% vs. 1.9%; aHR, 1.57; 95% CI: 0.86- 2.88; p=0.14), MI (0.8% vs. 1.0%; aHR, 0.62; 95% CI: 0.29 - 1.33; p=0.22), stroke (1.0% vs. 0.9%; aHR, 1.25; 95% CI: 0.58-2.69; p=0.57), and repeat revascularisation (4.4% vs. 4.0%; aHR, 1.23; 95% CI: 0.86-1.77; p=0.25) also did not differ between the groups.
Ad hoc PCI using DES appears to be feasible for angina patients at a relatively low risk of procedure. This approach may reasonably be performed with evaluation of objective ischaemia using non-invasive or invasive tests.
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