상악 치아군의 저항중심의 위치에 관한 3차원 유한요소 해석

정광모,성상진,이기준,전윤식,모성서 대한치과교정학회 2009 대한치과교정학회지 Vol.39 No.2

최근 골내 고정 형태의 temporary anchorage device (TAD)를 많이 이용하게 되면서 다양한 위치로부터 그리고 강한 교정력을 이용할 수 있게 되었다. 이에 따라 치아군의 이동양상을 예측하고 치료계획을 세우기 위하여 다양한 치아군의 저항중심의 위치에 대한 이해가 필요하게 되었다. 본 연구에서는 3차원 유한요소해석을 이용하여 상악 4전치, 6전치 그리고 상악 전치열에서 3차원적 저항중심의 위치를 조사하고자 하였다. 이를 위하여 상악 전치열 14개 치아와 치근막 및 치조골의 3차원 유한요소모델을 제작하였고, 각 치아군별로 치관부를 협측, 설측 호선, 설측 splint wire로 고정하여 개별 치아이동을 최소화하고 적용된 힘이 치아에 고루 분산되도록 하였다. 상악 중절치 절단연의 중점에서 연장된 와이어 빔에 수직, 수평으로 100 g 또는 200 g의 힘을 가하여 치아의 변위를 해석하고, 각 치아군에 속한 치아들이 최대한 평행이동 되는 힘의 적용부위를 저항중심으로 정의하였다. 연구결과 상악 4전치군의 저항중심은 상악 중절치 절단연으로부터 치근방향 13.5 mm, 후방 12.0 mm, 상악 6전치군은 상악 중절치 절단연으로부터 치근방향 13.5 mm, 후방 14.0 mm에 위치하였으며 상악 전치열군의 저항중심은 상악 중절치 절단연으로부터 치근방향 11.0 mm, 후방 26.5 mm에 위치하였다. 본 유한요소 실험모델을 이용하여 얻은 결과는 교정치료의 효율성을 높일 수 있으리라 생각된다. Objective: The aim of this study was to investigate the 3-dimensional position of the center of resistance of the 4 maxillary anterior teeth, 6 maxillary anterior teeth, and the full maxillary dentition using 3-dimensional finite element analysis. Methods: Finite element models included the whole upper dentition, periodontal ligament, and alveolar bone. The crowns of the teeth in each group were fixed with buccal and lingual arch wires and lingual splint wires to minimize individual tooth movement and to evenly disperse the forces to the teeth. A force of 100 g or 200 g was applied to the wire beam extended from the incisal edge of the upper central incisor, and displacement of teeth was evaluated. The center of resistance was defined as the point where the applied force induced parallel movement. Results: The results of study showed that the center of resistance of the 4 maxillary anterior teeth group, the 6 maxillary anterior teeth group, and the full maxillary dentition group were at 13.5 mm apical and 12.0 mm posterior, 13.5 mm apical and 14.0 mm posterior, and 11.0 mm apical and 26.5 mm posterior to the incisal edge of the upper central incisor, respectively. Conclusions: It is thought that the results from this finite element models will improve the efficiency of orthodontic treatment.

기능적 자기공명 영상법의 이해

서정진,정광우,강형근 全南大醫大 2003 전남의대학술지 Vol.39 No.4

모바일 비즈니스 수익 모델 분류에 관한 탐색적 연구

이대용,정광진,김희철 조선대학교 경영경제연구소 2002 經營經濟硏究 = Management and economics research Vol.25 No.2

인트라넷 이용채택에 관한 연구

이대용,정광진 조선대학교 경영경제연구소 2000 經營經濟硏究 = Management and economics research Vol.23 No.1

UV-TiO_2 광촉매 반응기를 이용한 미생물의 살균효과

김시욱,이정섭,정혜광,박열,윤성명,유진철,이범규,이인화,박진열 조선대학교 환경연구소 1998 環境硏究 Vol.14 No.1

UV-TiO_2 반응기를 이용하여 Escherichia coli와 Aspergillus oryzae var. oryzae의 살균효과를 측정하였다. 254㎚에서 최대 14 watt의 자외선 방출량을 내는 램프를 원형 Pyrex유리관 중앙에 설치하였고 TiO_2는 석영관에 박막증착(Thin Film Coating)된 형태와 슬러리 형태로 나누어 회분식으로 살균정도를 측정하였다. E. coli에 대한 살균력은 1.7×10^7 cells/㎖에 대해 5분간 자외선 조사를 하였을 경우 2.0×10^2 cells/㎖으로 감소하였고, 자외선 조사와 함께 슬러리 형태의 TiO_2를 첨가하였을 경우에는 3.4×10 cells/㎖으로, 자외선 조사와 함께 TiO_2가 석영관에 박막증착된 경우에는 7.6×10^2 cells/㎖으로 감소하였다. 한편 위와 같은 조건에 유리관 하부에서 기포를 주입수 11분 동안 자외선을 조사시킨 경우에는 1.3×10^2 cells/㎖으로, 자외선 조사와 함께 슬러리 형태의 TiO_2를 첨가하였을 경우에는 1×102 cells/㎖으로, 자외선 조사와 함께 TiO_2가 박막증착된 경우에는 7.9×10 cells/㎖을 나타내었다. 결국 UV-TiO_2 반응기에 사용되는 TiO_2가 슬러리 형태일 때 최대 살균효과를 나타내었으나 기포가 첨가되었을때는 오히려 살균에 장애를 받는 것으로 나타난 반면 석영관에 박막증착된 경우에는 기포가 첨가되는 것이 살균에 효과적인 것으로 관찰되었다. The killing effect of UV-TiO_2 photocatalytic system on the Escherichia coli DH5-α and Aspergillus oryzae var. oryzae (KCTC 6095) was studied. The UV lamp which emits maximum 14 watts at 254 ㎚ was set on the center of pyrex round glass tube. Two types of TiO_2, one of which is slurry and another which is thin film coated form, were used to determine the killing effect. When UV was irradiated to 1.7×10^5 cells/㎖ of E. coli for 11 min, the living cell number decreased to 4.0×10^0 cells/㎖. The effect of UV system together with slurried TiO_2 was less than 1 cells/㎖, whereas that of UV-coated TiO_2 system decreased to 7.1×10^3 cells/㎖. To study the effect of bubble on the killing of microorganisms, air was bubbled to the bottom of glass tube. When 1.7×10^5 cells/㎖ were exposed to UV for 11 min in combination with air bubble, the living cell number decreased to 1.3×10^2 cells/㎖. In the same condition except the addition of slurried TiO_2, the living cells were 1×10^2 cells/㎖. However, more cells could be killed by the system which consists of UV, coated TiO_2, and air bubble (7.9×10^1 cells/㎖). From these results, it was found that UV-slurried system is the most effective one, but its killing effect is not stimulated by air bubble. However, bubbling was very effective in the UV-coated TiO_2 system.

UV-TiO₂광촉매 반응기를 이용한 미생물의 살균효과

김시욱,이정섭,정해광,박열,윤성명,유진철,이범규,이인화,박진열 조선대학교 환경공해연구소 1998 環境公害硏究 Vol.14 No.-

UV-TiO_(2) 반응기를 이용하여 Escherichia coli와 Aspergillus oryzae var. oryzae의 살균효과를 측정하였다. 254 ㎚에서 최대 14 watt의 자외선 방출량을 내는 램프를 원형 Pyrex유리관 중앙에 설치하였고 TiO_(2)는 석영관에 박막증착(Thin Film Coating)된 형태와 슬러리 형태로 나누어 회분식으로 살균정도를 측정하였다. E. coli에 대한 살균력은 1.7× 10^(7) cells/㎖에 대해 5분간 자외선 조사를 하였을 경우 2.0× 10^(2) cells/㎖으로 감소하였고, 자외선 조사와 함께 슬러리 형태의 TiO_(2)를 첨가하였을 경우에는 3.4× 10 cells/㎖으로, 자외선 조사와 함께 TiO_(2)가 석영관에 박막증착된 경우에는 7.6× 10^(2) cells/㎖으로 감소하였다. 한편 위와 같은 조건에 유리관 하부에서 기포를 주입후 11분 동안 자외선을 조사시킨 경우에는 1.3× 10^(2) cells/㎖으로, 자외선 조사와 함께 슬러리 형태의 TiO_(2)를 첨가하였을 경우에는 1× 100 cells/㎖으로, 자외선 조사와 함께 TiO_(2)가 박막증착된 경우에는 7.9× 10 cells/㎖을 나타내었다. 결국 UV-TiO_(2) 반응기에 사용되는 TiO_(2)가 슬러리 형태일 때 최대 살균효과를 나타내었으나 기포가 첨가되었을때는 오히려 살균에 장애를 받는 것으로 나타난 반면 석영관에 박막증착된 경우에는 기포가 첨가되는 것이 살균에 효과적인 것으로 관찰되었다. The killing effect of UV-TiO_(2) photocatalytic system on the Escherichia coli DH5-慣 and Aspergillus oryzae var. oryzae (KCTC 6095) was studied. The UV lamp which emits maximum 14 watts at 254 nm was set on the center of pyrex round glass tube. Two types of TiO_(2), one of which is slurry and another which is thin film coated form, were used to determine the killing effect. When UV was irradiated to 1.7 * 10^(5) cells/??of E. coli for 11 min, the living cell number decreased to 4.0 * 1.0^(0) cells/?? The effect of UV system together with slurried TiO_(2) was less than 1 cells/?? whereas that of UV-coated TiO_(2) system decreased to 7.1 * 10^(3) cells/?? To study the effect of bubble on the killing of microorganisms, air was bubbled to the bottom of glass tube. When 1.7 * 10^(5) cells/??were exposed to UV for 11 min in combination with air bubble, the living cell number decreased to 1.3 x 10^(2) cells/?? In the same condition except the addition of slurried TiO_(2), the living cells were 1 * 10^(2) cells/?? However, more cells could be killed by the system which consists of UV, coated TiO_(2), and air bubble (7.9 * 10^(1) cells/??. From these results, it was found that UV-slurried system is the most effective one, but its killing effect is not stimulated by air bubble. However, bubbling was very effective in the UV-coated TiO_(2) system.

유용성 도료와 수용성 도료의 유해성 비교에 관한 연구 : 자동차 보수용 도료를 중심으로

권은혜,김광식,오정룡,최정근,정윤석,이유진,김은아,송세욱,정호근 한국산업위생학회 2001 한국산업보건학회지 Vol.11 No.1

The purpose of this study is to substitute water-based painting materials for the current solvent-based ones used in motor-repairing process to minimize the exposure of organic solvents to the painters. This study assessed the exposure of organic solvents to the painters using water-based and solvent-based painting materials and compared compositions, painting processes and the health hazards of the application of these alternative painting materials. The results of this study are as follows. 1. solvent-based painting materials used in motor-repairing process consist of various organic solvents, which consist primarily of toluene, xylene, ethyl benzene, ethyl methyl bezene, trimethyl bezene, ethyl acetate, butyl acetate, methyl isobutyl ketone, 2-ethoxy ethanol, 2-ethoxy ethyl acetate and toluene-2.4-diisocianate and the others. These organic solvents are know as health-hazardous substances. But water-based painting materials are high-solid, low-solvent ones and consist of such two organic solvents as 2-butoxy ethanol and 2-heptanone and the others. 2. The painters using solvent-based painting materials in motor-repairing process are exposed to various organic acetate, methyl isobutyl ketone, trimethyl benzene, 2-ethoxy ethanol, and 2-ethoxy ethyl acetate. But the painters using solvent-based ones are only exposed to 2-butoxy ethanol and 2-heptanone. 3. By using water-based painting materials in stead of solvent-based painting materials containing health-hazardous organic solvents, the exposure of such organic solvents in the painter's breathing zone can be largely prevented. 4. This study recommends water-based painting materials as substitutes for the current solvent-based ones used in motor-repairing process to minimize the exposure of organic solvents to the painters.

토양 미생물인 Streptomyces tubercidicus에서 분리한 GTPcyclohydrolase Ⅰ 저해제

한지만,김시욱,이인화,박열,정혜광,윤성명,유진철 조선대학교 약학연구소 1998 藥學硏究誌 Vol.19 No.1

GTP cyclohydrolase I (EC 3.5.4.16) catalyzes the conversion of GTP to D-erythro-7,8-dihydroneopterin triphosphates and formic acid. and thus performs the first committing step in the biosynthesis of the pteridine moiety of folk acid in microorganisms and of tetrahydrobiopterin in higher animals. GTP cyclohydrolase I isolated from Streptomyces tubercidicus was inhibited by DL-6-methyl-5,6,7,8-tetrahydropterin and xanthopterin, and was not inhibited by tetrahydrofolic acid, pterin, pterin-6-carboxylic acid, biopterin, neopterin, ribofravin. These results suggest that bacterial GTP cyclohydrolase I may be regulated by its metaboilic end product.

Anti-oxidant and anti-inflammatory activities of the various kinds of herbal tea

( Jin Wook Lee ),( Hyun Ji Eo ),( Gwang Hun Park ),( Hun Min Song ),( So Hee Woo ),( Mi Kyoung Kim ),( Jung Hye Eom ),( Man Hyo Lee ),( Jeong Rak Lee ),( Jin Suk Koo ),( Jin Suk Koo ) 대한본초학회 2014 大韓本草學會誌 Vol.29 No.2

Objectives : Reactive oxygen species (ROS) are involved in a wide spectrum of diseases including chronic inflammation and cancer. In this study, we investigated the antioxidant activities and anti-inflammatory effects of the extracts from the herbal teas such as Lonicera japonica Thunberg (L. japonica), Chrysanthemum morifolium Ramat (C. morifolium), Mentha arvensis L. (M. arvensis), and P.rhizoma. Methods : Anti-oxidant activity was evaluated using DPPH radical scavenging assay and Fe2+ chelating assay. And DNA cleavage assay was performed to evaluate an anti-oxidative effect. Anti-inflammatory effect was performed using NO generation assay and western blot in LPS-stimulated RAW264.7 cell line. Results : L. japonica scavenged DPPH radical by 9.8% at 12.5 μg/ml, 24.8% at 25 μg/ml, 34.3% at 50 μg/ml, 61.1% at 100 μg/ml and 75.8% at 200 μg/ml, respectively. In addition, C. morifolium and M. arvensis removed DPPH radical by 15.6% and 10.4% at 12.5 μg/ml, 34.8% and 22.8% at 25 μg/ml, 66.9% and 43.3% at 50 μg/ml, 87.4% and 69.1% at 100 μg/ml, and 92.1% and 73.2% at 200 μg/ml, respectively. However, P. rhizoma did not affect on DPPH radical scavenging. The Fe2+ chelating activity was highest in L. japonica, but lowest in P. rhizoma among the herbal teas. In addition, the extracts from L. japonica, C. morifolium and M. arvensis inhibited oxidative DNA damage via its anti-oxidant activity. In anti-inflammatory effect, the extracts from C. morifolium inhibited NO production. In addition, it suppressed the NF-κB signaling pathway in LPS-stimulated RAW 264.7 cells. Conclusions : Together, this study indicates that L. japonica, M. arvensis and C. morifolium possess the protective effect against the oxidative DNA damage. Furthermore, C. morifolium exerts an anti-inflammatory effect.

Induction of Cytochrome P450 1A and 2B by α-and β-Ionone in Sprague Dawley Rats

Jeong, Hye Gwang,Chun, Young-Jin,Yun, Chul-Ho,Moon, Chang-Kiu,Lee, Hye-Sook,Han, Sang Seop,Lee, Eung-Seok,Jeong, Tae Cheon 영남대학교 약품개발연구소 2002 영남대학교 약품개발연구소 연구업적집 Vol.11 No.-

β-lonone has been reported to induce the cytochrome P450 (P450) 2B1 in rats. In this study, the effects of and an isomer, α-lonone, on liver P450 1A and 2B experssion in Sprague Dawley rats were investigated. Subctaneous administration of α-and β-ionone 72 and 48hr prior to sacrificing the animals induced the liver microsomal P450 1A and 2B proteins. P450 2B1 induction was associated with the accumulation of its corresponding mRNA. Induction by β-ionone was much higher than that by α-ionone in both the mRNA and protein levels. When the route of administration was compared. P450 2B was induced more strongly after oral administration compared to that after subcutaneous injection. A single oral dose of 100, 300 and 600 mg/kg of α- and β-ionone for 24 h induced P450 2B-1selective pantoxyresorufin O-depentylase activity comparably in a dose-dependent manner. In addition, α- and β-ionone might be potent P450 2B1 inducers in rats, and that both ionones may be useful for examining the role of metabolic activation in chemical-induced toxicity where metabolic activation is required.