• Journal of Life Science
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• v.26 no.1
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• pp.91-100
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• 2016

Angiogenesis is essential for the pathophysiological processes of embryogenesis, tissue growth, diabetic retinopathy, psoriasis, wound healing, rheumatoid arthritis, cardiovascular diseases, and tumor growth. Inhibition of angiogenesis represents an attractive therapeutic approach for the treatment of angiogenic diseases such as cancer. However, uncontrolled angiogenesis is also necessary for tumor development and metastasis. Inhibition of vascular endothelial growth factor (VEGF) signaling, a critical factor in the induction of angiogenesis, cause robust and rapid changes in blood vessels of tumors and therefore VEGF constitutes a target for such anti-angiogenic therapy. Recently, since natural compounds pose significantly less risk of deleterious side effects than synthetic compounds, a great many natural resources have been assessed for useful substance for anti-angiogenic treatment. Here we evaluated the anti-angiogenic effects of a hot water extract of Scutellaria baicalensis (SBHWE) using in vitro assays and ex vivo animal experiments. Our results show that SBHWE dose-dependently abrogated vascular endothelial responses by inhibiting VEGF-stimulated migration and invasion as well as tube formation in a human umbilical vein endothelial cell (HUVEC) model, without cytotoxicity, as determined by a cell viability assay. Further study revealed that SBHWE prevented VEGF-induced neo-vascularization in a rat aortic ring sprouting model. Taken together, our findings reveal an anti-angiogenic activity of Scutellaria baicalensis and suggest that SBHWE is a novel candidate inhibitor of VEGF-induced angiogenesis.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.15 no.5
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• pp.175-181
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• 2005

Ingots of rutile single crystals were grown by the skull melting method, and their characteristics were compared in terms of melt-dwelling time for each melt. The method is based on direct inductive heating of an electrically conducted melt by an alternating RF field, and the heating is performed by absorption of RF energy. $TiO_2$ is an insulator at room temperature but its electric conductivity increases elevated temperature. Therefore, titanium metal ring(outside diameter : 6cm, inside diameter : 4cm, thickness 0.2cm) was embedded into $TiO_2$, powder (anatase phase, CERAC, 3N) for initial RF induction heating. Important factors of the skull melting method are electric resistivity of materials at their melting point, working frequency of RF generator and cold crucible size. In this study, electric resitivity of $TiO_2$, $(10^{-2}\~10^{-1}\;{\Omega}{\cdot}m)$ at its melting point was estimated by compairing the electric resitivities of alumina and zirconia. Inner diameter and height of the cold crucible was 11 and 14cm, respectively, which were determined by considering of the Penetration depth $(0.36\~1.13cm)$ and the frequency of RF generator.

• Korean Journal of Ichthyology
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• v.27 no.2
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• pp.133-141
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• 2015

Age and growth of redlip mullet, Chelon haematocheilus were determined using samples collected in Han River estuary of Korea from June, 2013 to May, 2014. Age was determined from sagital otoliths and Annul marks were formed in January once a year. In addition, spawning season was estimated in May, thus first ring was formed 8 months. The mullets were principally composed of 0 to 3 years old and the oldest was 9 years old. Relationship between standard length (SL) and total weight (TW) were $TW=0.0124SL^{3.0133}$($r^2=0.9931$). The Von Bertalanffy growth parameters estimated were $L_{\infty}$ 61.3, $W_{\infty}$ 3,230.6, K 0.29/year, $t_0$ - 0.05 year.

• Journal of Microbiology and Biotechnology
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• v.13 no.4
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• pp.529-536
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• 2003

The growth-inhibitory activity of Cassia tora seed-derived materials against seven intestinal bacteria was examined in vitro, and compared with that of anthraquinone, anthraflavine, anthrarufin, and 1-hydroxyanthraquinone. The active constituent of C. tore seeds was characterized as quinizarin, using various spectroscopic analyses. The growth responses varied depending on the compound, dose, and bacterial strain tested. At 1 mg/disk, quinizarin exhibited a strong inhibition of Clostridium perfringens and moderate inhibition of Staphylococcus aureus without any adverse effects on the growth of Bifidobacterium adolescentis, B. bifidum, B. longum, and Lactobacillus casei. Furthermore, the isolate at 0.1 mg/disk showed moderate and no activity against C. perfringens and S. aureus. The structure-activity relationship revealed that anthrarufin, anthraflavine, and quinizarin moderately inhibited the growth of S. aureus. However. anthraquinone and 1-hydroxyanthraquinone did not inhibit the human intestinal bacteria tested. As for the morphological effect of 1 mg/disk quinizarin, most strains of C. perfringens were damaged and disappeared, indicating that the strong activity of quinizarin was morphologically exhibited against C. perfringens. The inhibitory effect on aflatoxin $B_1$ biotransformation by anthraquinones revealed that anthrarufin ($IC_50,\;11.49\mu\textrm{M}$) anthraflavine ($IC_50,\;26.94\mu\textrm{M}$), and quinizarin ($IC_50,\;4.12\mu\textrm{M}$), were potent inhibitors of aflatoxin ${B_1}-8,9-epoxide$ formation. However, anthraquinone and 1-hydroxyanthraquinone did not inhibit the mouse liver microsomal sample to convert aflatoxin $B_1$ to aflatoxin ${B_1}-8,9-epoxide$. These results indicate that the two hydroxyl groups on A ring of anthraquinones may be essential for inhibiting the formation of aflatoxin ${B_1}-8,9-epoxide$. Accordingly, as naturally occurring inhibitory agents, the C. tora seed-derived materials described could be useful as a preventive agent against diseases caused by harmful intestinal bacteria, such as clostridia, and as an inhibitory agent for the mouse liver microsomal conversion of aflatoxin $B_1$ to aflatoxin ${B_1}-8,9-epoxide$.

• Journal of the Korean Wood Science and Technology
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• v.43 no.4
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• pp.421-428
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• 2015

This study was carried out to investigate the relationship between anatomical characteristics and growth rate of Quercus rubra from different origins of seed. Anatomical characteristics showed that all Quercus rubra species were ring-porous woods with 1~3 layers of large pores in earlywood, but the latewood had small pores oriented in radial direction. There were slight differences in libriform fiber length and vessel element diameter in the earlywood among different provenance origins of seeds. In growth rate, the libriform fiber length and vessel element diameter was negative correlation in the earlywood, but not correlative in the latewood, and vessel element length was not correlative in the early and latewood, Volumetric composition of libriform fiber and ray in latewood was higher than those in ear lywood, and a higher composition of vessel element was observed in earlywood. Ray height was the range of from 11 to 15 cells.

• The Korean Journal of Ecology
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• v.1 no.2
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• pp.66-71
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• 1977

The growth of red and black pines in Muan, Seochen, Gapyeong and Kochang areas was compared by means of the growth of annual ring width and stem analysis to study the process of damages caused by pine needle gall midge. Red pine forest of Seocheon area began to suffer by pine needle gall midge from 1961 and the damage was to becoming severe from 1967. The damage became so intense tha tmany forests are withering to death from spring of 1975. Black pine forest also began to suffer from 1973. Red pine forest of Muan area was supposed to be suffered from 1973. Red pine forest of Kochang area suffered by pine needle gall midge from 1967. It seems that the damage became severe from 1973 and that black pine forest was also badly damaged from that time. Red pine forest of the control plot, Gapyeong area, began to suffer from 1967 and it also became intense from 1973. Although the areas of Seocheon, Muan, Kochang, and Gapyeong are different from each other in terms of locality and the infitration period of pine needle gall equally from 1967 due to mass development of population or other factors and the damage became more intense from 1973. Black pine forest was also badly damaged from that time. Black pine seems to be stronger in insect resistant than red pine. This can be justified by the fact that it began to suffer belatedly in each area and the degree of damage is moderate. The damage of Seocheon area is the severest following Kochang. Muan area is relatively moderate but the forest becoming decrease in growth.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1997.10a
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• pp.129-133
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• 1997

본 연구에서는 LiNbO$_3$ 단결정 소재의 광손상에 대한 저항성을 향상시키는 첨가물로 잘 알려져 이쓴 MgO 및 ZnO를 첨가하여 육성한 조화용융조성(congruent melting composition)의 LiNbO$_3$ 단결정의 domain 구조는 이들 dopants를 첨가함에 따라 single domain에서 ring 형태의 주기적인 domains으로 변화함을 확인하였고, 첨가된 이온이 domain 형성에 미치는 영향을 전자현미경(SEM-WDS)으로 관찰하였다. 또한, 육성한 [Li1-5xNb5(x-y)Mg(or Zn)5y]Nb1-4x+3yO3 단결정들의 유전율(전이온도) 변화 및 광학적 특성[광투과율, 굴절률]을 측정하여 undoped LiNbO$_3$단결정과 비교하였다. 첨가물을 첨가함에 따라 전이온도는 약 20~3$0^{\circ}C$정도 증가하였으며, 10-3 order의 굴절률 변동치를 나타내었다. 또한, 육성된 결정들의 투과율은 대체로 70~80%를 나타내었고, 첨가물을 첨가함에 따라 흡수단과 OH- 흡수 band는 단파장쪽으로 각각 약 5~10nm, 40nm이동됨을 확인하였다. 이는 LiNbO$_3$단결정의 광손상 저항성이 향상되었음을 간접적으로 보여주는 결과이다.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.14 no.5
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• pp.199-203
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• 2004

Feasibility of 3Y-TZP for dental implant abutment was evaluated under the Hertzian cyclic fatigue by examining the extent of the indentation damage and strength degradation. Fatigue test was conducted at contact loads of 500 to 3000 N and up to $10^6$ cycles in exact in vitro environments. At 500 N, no strength degradation and crack generation was observed up to $5\times10^5$ contact cycles. As load rose, the dramatic reduction in strength was observed when the damage transition from ring to radial crack occurred. The. extent of strength degradation was more pronounced in vitro environment probably due to chemical corrosion of artificial saliva through cracks introduced during large numbers of contacts.

• KSBB Journal
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• v.27 no.2
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• pp.121-126
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• 2012

In order to explore structural features of minoxidil analogs with a view of enhancing lysyl hydroxylase (LH) inhibitory activity, molecular holographic QSAR (HQSAR) and CoMSIA (comparative molecular similarity indices analysis) were performed. The results from the atomic contributions with optimized the HQSAR 6-2 model indicated that, in case of pyrimidine-1-N-oxide substituent, C2 atom of pyrimidine ring and C'3-C'4 bond of 4-piperidinol group showed the highest impact on the inhibitory activity towards LH enzyme. It was also evident from the information of the optimized CoMSIA F5 model that the inhibitory activity mainly depended on the hydrophobic field contribution (36%) and the hydrogen bond (H-bond) field contribution (49.2%) of substrate molecule. Particularly, it is predicted that the functional groups which disfavor H-bond acceptors in large space around the piperidinol group and also the functional groups which favor the H-bond acceptors at C'4 (& C'5) atom in $R_5$ group play a role for increased inhibitory activity. With this in mind, it is likely that a novel candidate having more improved inhibitory activity on hair growth could be designed in the future.

• Journal of Korean Society of Forest Science
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• v.69 no.1
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• pp.6-12
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• 1985

A computer program for stem analysis has been prepared by using BASIC language. Annual-ring counts and other input data can be directly entered for necessary calculation, and outputs are data lists, cross-section areas, age-height relationships, growth rates, total, annual, and mean increments of height, D.B.H. and volume for an individual tree. The sectional log volumes are calculated by Huber's formula, and the growth rates by Pressler's in this program. A copy of the program listing is in appendix I.