• Journal of Chest Surgery
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• v.35 no.6
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• pp.407-419
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• 2002

Atherosclerosis is a chronic inflammatory disease of the arterial wall characterized by progressive accumulation of lipids, cells, and extracellular matrix. Matrix metalloproteinases(MMPs) and tissue inhibitor of metalloproteinases(TIMPS) contribute to vascular matrix remodeling in atherosclerosis, and some cytokines may play role in the synthesis or activation of MMPs or TIMPs. Material and Method： We produced experimental atherosclerotic plaques in 9 rabbits by atherogenic hypercholesterol diet for 12 weeks, and 10 other rabbits were used as control group with standard laboratory chow, At that time, 19 rabbits were sacrificed and aorta, coronary arteries and blood specimens were prepared. The expressions of MMP-9, TIMP-2 and interleukin(IL)-18, and the bioactivity of IL-6 were investigated with H&E stain, immunohistochemical stain, immunoblotting(Western blot analysis), and bioassay. Result： Serum cholesterol in the experimental group increased up to 1258$\pm$262 mg/dL(control group： 41$\pm$7 mg/dL). All experimental group showed well-developed atherosclerotic plaques in aorta and coronary artery. The expression of MMP-9 in aorta and coronary artery of the experimental group showed significant increase than that of the control group by immunohistochemistry. Among the experimental group, complicated lesions with intimal rupture or complete luminal occlusion, demonstrated stronger expression of MMP-9. Interestingly, there was no difference in expression of TIMP-2 between the experimental and the control group. These findings were confirmed by Western blot analysis. The bioassay revealed significant up-regulation of serum bioactivity of IL-6 in the experimental group(4819.60$\pm$2021.25 IU/$m\ell$) compared to that of IL-6 in the control group(27.20 $\pm$ 12.19 IU/$m\ell$). IL-18 was expressed in all atherosclerotic plaques, whereas little or no expression was detected in the control group. Conclusion： The increased MMP-9 expression along with the unchanged TIMP-2 expression seem to be contributory factors in extracellular matrix degradation in atherosclerosis. Focal overexpression of MMP-9 may promote plaque destabilization and cause complications of atherosclerotic plaques such as thrombosis with/without acute coronary syndrome. Elevation of IL-6 and IL-18 may be more than just markers of atherosclerosis but actual participants in lesion development. Identification of critical regulatory pathway is important to improve the understanding of the cellular and molecular basis of atherosclerosis and may open the way for novel therapeutic strategies.

• The Journal of the Petrological Society of Korea
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• v.15 no.3 s.45
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• pp.139-153
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• 2006

For the characteristics of rock material and standardization, flagstones of the trifurcated path in Jongmyo Royal Shrine, registered as World Cultural Heritage, were studied on the basis of petrographic, petrochemical and magnetic properties. The flagstones are composed mainly of pale gray fine to medium grained hornblende biotite granite, pale gray fine to medium grained biotite granite, pale pink medium to coarse grained biotite granite, pink medium to coarse grained biotite granite and minor pegmatite and schist. Flagstone represents the average size of $65cm{\times}4cm$ (standard deviation $12cm{\times}7cm$) and suitable (34.7%), common (41.4%) and unsuitable (23%) in roughness. It is interpreted that pale pink and pink granite, pegmatite, schist and other flagstones with unsuitable state are not original rock materials and were exchanged during restoration, in the past. The number of these non-original rock materials is about 560 flagstones. We suggests that the standard flagstone of the trifurcated path is pale gray fine to medium grained biotite granite (${\pm}$hornblende in trace), 70wt.% in $SiO_2$, content, and ${\pm}0.1{\times}10^{-3}\;SI$ in magnetic susceptibility.