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11.
Kyung Seob Lim Jun-Kyu Park Myung Ho Jeong Jae-Woon Nah Dae Sung Park Jong Min Kim Jung Ha Kim So Youn Lee Eun Jae Jang Suyoung Jang Hyun Kuk Kim Doo Sun Sim Keun-Ho Park Young Joon Hong Youngkeun Ahn Jung Chaee Kang 《Journal of materials science. Materials in medicine》2016,27(4):66
The aim of this study was to evaluate antiproliferative sirolimus- and antioxidative alpha-lipoic acid (ALA)-eluting stents using biodegradable polymer [poly-l-lactic acid (PLA)] in a porcine coronary overstretch restenosis model. Forty coronary arteries of 20 pigs were randomized into four groups in which the coronary arteries had a bare metal stent (BMS, n = 10), ALA-eluting stent with PLA (AES, n = 10), sirolimus-eluting stent with PLA (SES, n = 10), or sirolimus- and ALA-eluting stent with PLA (SAS, n = 10). A histopathological analysis was performed 28 days after the stenting. The ALA and sirolimus released slowly over 30 days. There were no significant differences between groups in the injury or inflammation score; however, there were significant differences in the percent area of stenosis (56.2 ± 11.78 % in BMS vs. 51.5 ± 12.20 % in AES vs. 34.7 ± 7.23 % in SES vs. 28.7 ± 7.30 % in SAS, P < 0.0001) and fibrin score [1.0 (range 1.0–1.0) in BMS vs. 1.0 (range 1.0–1.0) in AES vs. 2.0 (range 2.0–2.0) in SES vs. 2.0 (range 2.0–2.0) in SAS, P < 0.0001] between the four groups. The percent area of stenosis based on micro-computed tomography corresponded with the restenosis rates based on histopathological stenosis in different proportions in the four groups (54.8 ± 7.88 % in BMS vs. 50.4 ± 14.87 % in AES vs. 34.5 ± 7.22 % in SES vs. 28.9 ± 7.22 % in SAS, P < 0.05). SAS showed a better neointimal inhibitory effect than BMS, AES, and SES at 1 month after stenting in a porcine coronary restenosis model. Therefore, SAS with PLA can be a useful drug combination for coronary stent coating to suppress neointimal hyperplasia. 相似文献
12.
Sang Su Kim Jun-Ki Chung Mun Heum Park Jong Kuk Kim Jae-Yong Kim Won-Jeong Kim 《Journal of Electroceramics》2006,17(2-4):151-155
The Bi3.4La0.6Ti3O12 (BLT) thin film and powder have been prepared by a sol-gel method with annealing at 700°C. Randomly oriented BLT thin film exhibits a large remanent polarization, 2P r = 72 μC/cm2, with a dc applied field strength of 320 kV/cm. Structure of sol-gel derived BLT powder has been investigated by neutron scatterings, and refined by a Rietveld method resulting a reasonable goodness of fit (wR p = 6.7%, and R p = 5.7%) using an orthorhombic (B2cb, a = 5.4221 Å, b = 5.4032 Å, and c = 32.8361 Å). Two different TiO6 octahedra exhibit different polarization directions; (100) from Ti(1)O6, and (011) from Ti(2)O6, which explains the observed large 2P r of the randomly oriented BLT thin film. 相似文献
13.
Emissions from fossil fuel combustion containing various heavy metals such as molybdenum are of public concern due to their adverse effects on human health and the environment. In this study, thermodynamic analyses were applied to determine the potential of sorbent technology to control molybdenum emissions from combustion sources. The effectiveness of four sorbents (Ca, Fe, Mg and Na based) was assessed for a wide range of temperatures. The adverse effects of chlorine and sulfur were also examined. Ca and Na-based sorbents were identified to be effective. 相似文献
14.
Whee Kuk Kim Dong Gu Kim Byung-Ju Yi 《Journal of Mechanical Science and Technology》1996,10(3):286-295
In this work, a planar three degree-of-freedom parallel mechanism as another type of assembly device which utilizes joint compliances is proposed. In order to generate the desired operational compliance characteristics at RCC point, these joint compliances can be adjusted either by properly replacing the joint compliances or by actively controlling stiffness at joints. The operational compliance matrix for this mechanism is obtained explicitly by symbolic manipulation, and its operational compliance characteristics are examined. It is found that the RCC point exists at the center of the workspace when the mechanism maintains symmetric configurations. Compliance characteristics and its sensitivity of this mechanism are analyzed with respect to the magnitude of the diagonal compliance components and two different matrix norms by measuring compliance sensitivity. It is expected that the analysis results provide the designer with a helpful information to determine a set of optimal parameters of this RCC mechanism. 相似文献
15.
Seyeon Oh Hyoung Moon Kim Sosorburam Batsukh Hye Jin Sun Taehui Kim Donghwan Kang Kuk Hui Son Kyunghee Byun 《International journal of molecular sciences》2022,23(16)
During skin aging, the volume of subcutaneous adipose tissue (sWAT) and the adipogenesis potential of adipose-derived stem cells (ASCs) decrease. It is known that the shortening of cilia length by pro-inflammatory cytokines is related to the decreased adipogenic differentiation of ASCs via increase in Wnt5a/β-catenin. High-intensity focused ultrasound (HIFU) is known to upregulate heat shock proteins (HSP), which decrease levels of pro-inflammatory cytokines. In this study, we evaluated whether HIFU modulates the cilia of ASCs by upregulating HSP70 and decreasing inflammatory cytokines. HIFU was applied at 0.2 J to rat skin, which was harvested at 1, 3, 7, and 28 days. All results for HIFU-applied animals were compared with control animals that were not treated. HIFU increased expression of HSP70 and decreased expression of NF-κB, IL-6, and TNF-α in sWAT. HIFU decreased the expression of cilia disassembly-related factors (AurA and HDAC9) in ASCs. Furthermore, HIFU increased the expression of cilia assembly-related factors (KIF3A and IFT88), decreased that of WNT5A/β-catenin, and increased that of the adipogenesis markers PPARγ and CEBPα in sWAT. HIFU increased the number of adipocytes in the sWAT and the thickness of sWAT. In conclusion, HIFU could selectively increase sWAT levels by modulating the cilia of ASCs and be used for skin rejuvenation. 相似文献
16.
Kim NK Cho S Lee SH Park HR Lee CS Cho YM Choy YH Yoon D Im SK Park EW 《Meat science》2008,80(4):1068-1073
Proteomic profiling by two-dimensional gel electrophoresis and mass spectrometry of longissimus dorsi muscle tissue from Korean native cattle identified seven proteins that are differentially expressed in animals producing low and high quality grade beef. The expression level of alpha actin is increased in high quality grade beef and the expression levels of T-complex protein 1 (TCP-1), heat shock protein beta-1 (HSP27), and inositol 1,4,5-triphosphate receptor type1 (IP3R1), a new protein to be associated with meat quality, are increased in low quality grade beef. In particular, the quantitation of HSP27 and IP3R1 by both silver staining and immunoblotting correlated well with intramuscular fat content, meat tenderness, and free calcium levels. The data suggest that HSP27 and IP3R1 are potential meat quality biomarkers and their identification provides new insight into the molecular mechanisms and pathways associated with overall beef quality. 相似文献
17.
18.
Non-toxic dyes and natural pigments were examined as potential substrates for a laccase-based time temperature integrator (TTI) prototype. Five compounds such as bromothymol blue (D1), methyl orange (D2), laccaic acid (P1), a pigment from bokbunja (Rubus coreanus) fruit (P2), and Gardenia blue pigment (P3) were all catalyzed, resulting in significant changes in color. CIE-Lab and ΔE appeared to have the most linear dependency on reaction time. Reaction rate constants, k, were estimated at 10–37°C with the coefficients of determination, R2, being the lowest at 0.94. The Arrhenius activation energies, Ea, were 42.6 66.1 kJ/mol depending on the substrate. The results show that alterations in Ea of this TTI is a very important finding in that Ea of the laccase-based TTI could be modulated with substrates to assess time-temperature history accurately and that a wide range of color compounds offer an opportunity for color-coded TTI to assure color blind individuals food safety. 相似文献
19.
Computational Analysis of Oxide Ion Conduction in Orthorhombic Perovskite Structured La0.9A0.1InO2.95 (A = Ca,Sr and Ba) 下载免费PDF全文
Mi‐Young Yoon Kuk‐Jin Hwang Dae‐Seop Byeon Joosun Kim Hae‐Jin Hwang Seong‐Min Jeong 《Journal of the American Ceramic Society》2015,98(2):515-519
Oxide ion conduction in orthorhombic perovskite structured oxides, La0.9A0.1InO2.95 (A = Ca, Sr and Ba) is analyzed using molecular dynamics simulation. Factors influencing oxide ion conductivity of the compositions considered are analyzed using radial distribution function, bond energies between dopant and oxide ions, and the diffusion path. It is known that perovskite oxides with smaller ion size mismatch between host and dopant ions have higher electrical conductivities. However, exceptions exist, such as a La0.9A0.1InO2.95 (A = Ca, Sr and Ba) system, where high electrical conductivities occur with large ion size mismatches. Based on this study, a dopant with smaller ion than host ion results in the formation of strong ionic bonds with oxide ions, suggesting that the A‐site dopant should be larger than the host ion for forming weaker O–A bonds. Consequently, the trade‐off between ion size mismatch and O–A bond needs to be considered for enhancing oxide ion conductivity of perovskite oxides. 相似文献
20.
Fabrication and characterization of double‐network agarose/polyacrylamide nanofibers by electrospinning 下载免费PDF全文
This study focused on the preparation of electrospun cross‐linked double‐network (DN) of agarose/polyacrylamide (PAAm) nanofibers. The agarose formed the first‐network that was physical‐linked by the agar helix bundles. After UV‐irradiation, the chemically crosslinked PAAm was formed as the second network. The resulting cross‐linked DN agarose/PAAm nanofibers were characterized by scanning electron microscopy (SEM), contact angle, attenuated total reflectance‐Fourier transform infrared spectroscopy (ATR‐FT‐IR), thermogravimetric analysis (TGA), and tensile test. SEM analysis shows the agarose/PAAM nanofibers present with the thickness of 187 nm. Agarose/PAAm nanofibers were showing FT‐IR spectral peaks at ~1660, 1590, and 1070 cm?1 indicating the presence of both agarose and polyacrylamide in the crosslinked DN Agarose/PAAm nanofiber sheet, it suggests the strong interaction and good compatibility between the two components. Agarose/PAAm nanofiber sheet was showing thermal stability close to the pure polyacrylamide. From the tensile test study, agarose/PAAm strength improved by 66.66% compared to the pure agarose. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 42914. 相似文献