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Relationships on Magnitude and Frequency of Freshwater Discharge and Rainfall in the Altered Yeongsan Estuary (영산강 하구의 방류와 강우의 규모 및 빈도 상관성 분석)

  • Rhew, Ho-Sang;Lee, Guan-Hong
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.16 no.4
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    • pp.223-237
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    • 2011
  • The intermittent freshwater discharge has an critical influence upon the biophysical environments and the ecosystems of the Yeongsan Estuary where the estuary dam altered the continuous mixing of saltwater and freshwater. Though freshwater discharge is controlled by human, the extreme events are mainly driven by the heavy rainfall in the river basin, and provide various impacts, depending on its magnitude and frequency. This research aims to evaluate the magnitude and frequency of extreme freshwater discharges, and to establish the magnitude-frequency relationships between basin-wide rainfall and freshwater inflow. Daily discharge and daily basin-averaged rainfall from Jan 1, 1997 to Aug 31, 2010 were used to determine the relations between discharge and rainfall. Consecutive daily discharges were grouped into independent events using well-defined event-separation algorithm. Partial duration series were extracted to obtain the proper probability distribution function for extreme discharges and corresponding rainfall events. Extreme discharge events over the threshold 133,656,000 $m^3$ count up to 46 for 13.7y years, following the Weibull distribution with k=1.4. The 3-day accumulated rain-falls which occurred one day before peak discharges (1day-before-3day -sum rainfall), are determined as a control variable for discharge, because their magnitude is best correlated with that of the extreme discharge events. The minimum value of the corresponding 1day-before-3day-sum rainfall, 50.98mm is initially set to a threshold for the selection of discharge-inducing rainfall cases. The number of 1day-before-3day-sum rainfall groups after selection, however, exceeds that of the extreme discharge events. The canonical discriminant analysis indicates that water level over target level (-1.35 m EL.) can be useful to divide the 1day-before-3day-sum rainfall groups into discharge-induced and non-discharge ones. It also shows that the newly-set threshold, 104mm, can just separate these two cases without errors. The magnitude-frequency relationships between rainfall and discharge are established with the newly-selected lday-before-3day-sum rainfalls: $D=1.111{\times}10^8+1.677{\times}10^6{\overline{r_{3day}}$, (${\overline{r_{3day}}{\geqq}104$, $R^2=0.459$), $T_d=1.326T^{0.683}_{r3}$, $T_d=0.117{\exp}[0.0155{\overline{r_{3day}}]$, where D is the quantity of discharge, ${\overline{r_{3day}}$ the 1day-before-3day-sum rainfall, $T_{r3}$ and $T_d$, are respectively return periods of 1day-before-3day-sum rainfall and freshwater discharge. These relations provide the framework to evaluate the effect of freshwater discharge on estuarine flow structure, water quality, responses of ecosystems from the perspective of magnitude and frequency.

Graves' Disease in Prepubertal Children Compared with Pubertal Children (소아 Graves병의 임상적 고찰 : 사춘기 이전군과 사춘기군의 비교)

  • Kim, Hyun Mi;Yoon, Ju Yun;Jung, Min Ho;Suh, Byung Kyu;Lee, Byung Churl
    • Clinical and Experimental Pediatrics
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    • v.46 no.1
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    • pp.76-82
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    • 2003
  • Purpose : The aim of this study was to determine whether differences exist in the presentation, clinical course, and outcome of Graves' disease between prepubertal children and adolescents. Methods : A retrospective chart review of 14 prepubertal(PREPUB, $7.2{\pm}0.9yr) and 38 pubertal (PUB, $12.4{\pm}1.5yr$) children with Graves' disease between January 1989 and November 1995 at St. Mary's Hospital and Kangnam St. Mary's Hospital was undertaken. Results : There were no significant differences in $T_3$, $T_4$, TSH between two the groups at diagnosis. The PUB group had significantly higher titers of antimicrosomal antibody(positive dilution factor $11,727.3{\pm}22,888.4$) than did the PREPUB group($2,111.5{\pm}2,285.0$, P<0.001). The PREPUB group had significantly higher titers of TSH-binding inhibitory immunoglobulin(TBII, $62.5{\pm}39.6$) than did the PUB group($44.9{\pm}10.4$, P<0.05) before treatment started. The duration(months) of medical therapy before thyroid function tests were normalized was longer in the PREPUB group than in the PUB group($T_3:6.8{\pm}5.0$ vs. $5.4{\pm}13.2$, $T_4:2.3{\pm}1.9$ vs. $2.1{\pm}2.2$, $TBII:26.7{\pm}24.0$ vs. $20.8{\pm}12.1$), especially that of TSH was significantly longer in the PREPUB group($14.6{\pm}11.0$ vs. $6.8{\pm}7.8$, P< 0.05). Total length of medical therapy was significantly longer in the PREPUB group than the PUB group($52.3{\pm}19.3$ vs. $37.9{\pm}16.3months$, P<0.01). During three years of antithyroid drug therapy, in the PREPUB group, the remission rate was lower and the relapse rate was higher than in the PUB group. Total length of treatment correlated negatively with chronological age(P=0.03). Conclusion : Prepubertal children require longer medical therapy to achieve a remission than do pubertal children. But there is an obvious need for more studies because of the small number of patients and the short duration of the follow-up.

A study on dietary habits, nutrient intakes and dietary quality in adults of a health screening and promotion center according to non-alcoholic fatty liver disease (건강증진센터 고객의 비알콜성 지방간 유무에 따른 식습관 및 영양섭취, 식사의 질에 관한 연구)

  • Chang, Ji Ho;Lee, Hye Seung;Kang, Eun Hee
    • Journal of Nutrition and Health
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    • v.47 no.5
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    • pp.330-341
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    • 2014
  • Purpose: The purpose of this study was to evaluate dietary habits, food intakes, nutrient intakes, and diet quality of non-alcoholic fatty liver disease in a health screening and promotion center. Methods: The total number of study subjects was 10,111 adults, where 3087 subjects (30.5%) were diagnosed as NAFLD. The dietary intakes were obtained using a food frequency questionnaire. They were then compared with the dietary reference intakes could be used in the future for development of diet and nutrition guidelines s (KDRIs). Results: Mean age of subjects in the normal group was $52.9{\pm}10.3yrs$ and body mass index (BMI) was $22.4{\pm}2.6kg/m^2$, and those of the NAFLD group were $55.1{\pm}9.2yrs$ and $25.4{\pm}2.9kg/m^2$. BMI, blood pressure of the NAFLD group were significantly higher than those of the normal group. The rates of skipping breakfast, overeating, and eating out were significantly could be used in the future for development of diet and nutrition guidelines er in the NAFLD group (p < 0.05, p < 0.000, p < 0.000 respectively). The speed of eating was fast in the NAFLD group (p < 0.000). The NAFLD group consumed significantly higher amounts of grains, meats, fish, seaweeds, kimchies, sugars, sweets, coffee, teas, and oils compared to the normal group (p < 0.05). Meanwhile, intakes of starch products, fruits, milk, and milk products were significantly lower in the NAFLD group compared with those of the normal group (p < 0.05). Riboflavin, calcium, and dietary fiber nutrient adequacy ratio (NAR) of the NAFLD group were significantly lower than those of the normal group. The Korean's dietary diversity score (KDDS) of the NAFLD group was lower than that of the normal group. Conclusion: In conclusion, we suggest that diet guidelines, such as increasing the intake of calcium and dietary fiber, reducing the intake of energy, fat, and simple carbohydrates, are necessary to improvement of NAFLD. The results could be used in the future for development of diet and nutrition guidelines for NAFLD.

Studies on Development of Prediction Model of Landslide Hazard and Its Utilization (산지사면(山地斜面)의 붕괴위험도(崩壞危險度) 예측(豫測)모델의 개발(開發) 및 실용화(實用化) 방안(方案))

  • Ma, Ho-Seop
    • Journal of Korean Society of Forest Science
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    • v.83 no.2
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    • pp.175-190
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    • 1994
  • In order to get fundamental information for prediction of landslide hazard, both forest and site factors affecting slope stability were investigated in many areas of active landslides. Twelve descriptors were identified and quantified to develop the prediction model by multivariate statistical analysis. The main results obtained could be summarized as follows : The main factors influencing a large scale of landslide were shown in order of precipitation, age group of forest trees, altitude, soil texture, slope gradient, position of slope, vegetation, stream order, vertical slope, bed rock, soil depth and aspect. According to partial correlation coefficient, it was shown in order of age group of forest trees, precipitation, soil texture, bed rock, slope gradient, position of slope, altitude, vertical slope, stream order, vegetation, soil depth and aspect. The main factors influencing a landslide occurrence were shown in order of age group of forest trees, altitude, soil texture, slope gradient, precipitation, vertical slope, stream order, bed rock and soil depth. Two prediction models were developed by magnitude and frequency of landslide. Particularly, a prediction method by magnitude of landslide was changed the score for the convenience of use. If the total store of the various factors mark over 9.1636, it is evaluated as a very dangerous area. The mean score of landslide and non-landslide group was 0.1977 and -0.1977, and variance was 0.1100 and 0.1250, respectively. The boundary value between the two groups related to slope stability was -0.02, and its predicted rate of discrimination was 73%. In the score range of the degree of landslide hazard based on the boundary value of discrimination, class A was 0.3132 over, class B was 0.3132 to -0.1050, class C was -0.1050 to -0.4196, class D was -0.4195 below. The rank of landslide hazard could be divided into classes A, B, C and D by the boundary value. In the number of slope, class A was 68, class B was 115, class C was 65, and class D was 52. The rate of landslide occurrence in class A and class B was shown at the hige prediction of 83%. Therefore, dangerous areas selected by the prediction method of landslide could be mapped for land-use planning and criterion of disaster district. And also, it could be applied to an administration index for disaster prevention.

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A Retrospective Study of the Radiotherapy Care Patterns for Patients with Laryngeal Cancer and Comparison of Different Korean Hospitals Treated from 1998 through 1999 (한국인 후두암 환자의 방사선치료 과정 및 내용에 관한 분석 (1998~1999년도))

  • Chung, Woong-Ki;Kim, Il-Han;Yoon, Mee-Sun;Ahn, Sung-Ja;Nam, Taek-Keun;Song, Ju-Young;Chung, Jae-Uk;Nah, Byung-Sik;Lee, Joon-Kyoo;Wu, Hong-Gyun;Lee, Chang-Geol;Lee, Sang-Wook;Park, Won;Ahn, Yong-Chan;Kang, Ki-Moon;Kim, Jung-Soo;Oh, Yoon-Kyeong;Cho, Moon-June;Park, Woo-Yoon;Kim, Jin-Hee;Choi, Doo-Ho;Yun, Hyong-Geun;Kim, Woo-Cheol;Yang, Dae-Sik;Sohn, Seung-Chang;Suh, Hyun-Suk;Ahn, Ki-Jung;Chun, Mi-Son;Lee, Kyu-Chan;Choi, Young-Min;Jeung, Tae-Sik;Kang, Jin-Oh
    • Radiation Oncology Journal
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    • v.27 no.4
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    • pp.201-209
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    • 2009
  • Purpose: To investigate the care patterns for radiation therapy and to determine inter-hospital differences for patients with laryngeal carcinoma in Korea. Materials and Methods: A total of 237 cases of laryngeal carcinoma (glottis, 144; supraglottis, 93) assembled from 23 hospitals, who underwent irradiation in the year of 1998 and 1999, were retrospectively analyzed to investigate inter-hospital differences with respect to radiotherapy treatment. We grouped the 23 hospitals based on the number of new patients annually irradiated in 1998; and designated them as group A (${\geq}$900 patients), group B (${\geq}$400 patients and <900 patients), and group C (<400 patients). Results: The median age of the 237 patients was 62 years (range, 25 to 88 years), of which 216 were male and 21 were female. The clinical stages were distributed as follows: for glottis cancer, I; 61.8%, II; 21.5%, III; 4.2%, IVa; 11.1%, IVb; 1.4%, and in supraglottic cancer, I; 4.3%, II; 19.4%, III; 28.0%, IVa; 43.0%, IVb; 5.4%, respectively. Some differences were observed among the 3 groups with respect to the dose calculation method, radiation energy, field arrangement, and use of an immobilization device. No significant difference among 3 hospital groups was observed with respect to treatment modality, irradiation volume, and median total dose delivered to the primary site. Conclusion: This study revealed that radiotherapy process and patterns of care are relatively uniform in laryngeal cancer patients in Korean hospitals, and we hope this nationwide data can be used as a basis for the standardization of radiotherapy for the treatment of laryngeal cancer.

The Analyses of Treatment Results and Prognostic Factors in Supradiaphragmatic CS I-II Hodgkin's Disease (횡경막상부에 국한된 임상적 병기 1-2기 호지킨병에서 치료 결과와 예후 인자의 분석)

  • Park Won;Suh Chang Ok;Chung Eun Ji;Cho Jae Ho;Chung Hyun Cheol;Kim Joo Hang;Roh Jae Kyung;Hahn Jee Sook;Kim Gwi Eon
    • Radiation Oncology Journal
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    • v.16 no.2
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    • pp.147-157
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    • 1998
  • Purpose : The aim of this retrospective study is to assess the necessity of s1aging laparotomy in the management of supradiaphragmatic CS I-II Hodgkin's disease. Prognostic factors and the usefulness of prognostic factor groups were also analyzed. Materials and Methods : From 1985 to 1995, fifty one Patients who were diagnosed as supradiaphragmatic CS I-II Hodgkin's disease at Yonsei Cancer Center in Seoul, Korea were enrolled in this study Age range was 4 to 67 with median age of 30. The number of patients with each CS IA, II A, and IIB were 16, 25, and 10, respectively. Radiotherapy(RT) was delivered using 4 or 6 MV photon beam to a total dose of 19.5 to 55.6Gy (median dose : 45Gy) with a 1.5 to 1.BGy per fraction. Chemotherapy(CT) was given in 2-12 cycles(median : 6 cycles). Thirty one Patients were treated with RT alone, 4 patients with CT alone and 16 patients with combined chemoradiotherapy. RT volumes varied from involved fields(3), subtotal nodal fields(18) or mantle fields(26). Results : Five-year disease-free survival rate(DFS) was $78.0\%$ and overall survival rate(05) was $87.6\%$. Fifty Patients achieved a complete remission after initial treatment and 8 patients were relapsed. Salvage therapy was given to 7 patients, 1 with RT alone, 4 with CT alone, 2 with RT+CT. Only two patients were successfully salvaged. Feminine gender and large media-stinal adenopathy were significant adverse prognostic factors in the univariate analysis for DFS. The significant adverse prognostic factors of OS were B symptom and clinical stage. When patients were analyzed according to European Organization for Research and Treatment of Cancer(EORTC) prognostic factor groups, the DFS in Patients with very favorable, favorable and unfavorable group was 100, 100 and $55.8\%$(p<0.05), and the 05 in each patients' group was 100, 100 and $75.1\%$(p<0.05), respectively. In very favorable and favorable groups, the DFS and 05 were all $100\%$ by RT alone, but in unfavorable group, RT with CT had a lesser relapse rate than RT alone. The subtotal nodal irradiation had better OFS than mantle RT in patients treated with RT. Conclusion : In present study, the DFS and OS in patients who did not undergo s1aging laparotomy were similar with the results in the literatures of which patients were surgically staged. Therefore, we may suggest that staging laparotomy would not influence the outcome of treatments. In univariate analysis, gender, large mediastinal adenopathy. B symptoms and clinical stage were significant prognostic factors for the survival rate. We confirm the usefulness of EORTC prognostic factor groups which may be a good.

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Clinical Features and the Natural History of Dietary Protein Induced Proctocolitis: a Study on the Elimination of Offending Foods from the Maternal Diet (식품 단백질 유발성 직결장염의 임상 소견과 식이 조절에 관한 연구)

  • Choi, Seon Yun;Park, Moon Ho;Choi, Won Joung;Kang, Una;Oh, Hoon Kyu;Kam, Sin;Hwang, Jin-Bok
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.8 no.1
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    • pp.21-30
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    • 2005
  • Purpose: The aim of this study was to identify the clinical features and natural history of dietary protein induced proctocolitis (DPIPC) and to detect the causative foods of DPIPC, and to evaluate the effect of elimination of the foods on the course of the disease. Methods: Between March 2003 and July 2004, data from 30 consecutive patients with DPIPC who were followed for over 6 months, was reviewed. The diagnostic criterion used for DPIPC was an increase in the number of eosinophils in the lamina propria (${\geq}60per$ 10 high-power fields). In breast feeding mothers, 5 highly allergenic foods were eliminated from the maternal diet for 7 days, namely, allergenic food groups such as dairy products, eggs, nuts and soybean, fish and shellfish, and wheat and buckwheat. We observed the disappearance or appearance of hematochezia after elimination or challenge with the offending foods. Results: Before diagnosis infants were breast-fed (93.3%) or formula-fed (6.7%). Mean age at symptom onset was $11.5{\pm}5.1$ (5~24) weeks, and mean age at diagnosis was $17.8{\pm}9.5$ (8~56) weeks. Duration from symptom onset to diagnosis was $6.3{\pm}6.7$ (0~36) weeks. Mean peripheral blood eosinophil count was $478{\pm}320$ (40~1,790)/$mm^3$ and eosinophilia (> $250/mm^3$) was observedin 90.0% of patients. None of patients were found to have an increased serum IgE level. Of 15 patients that received sigmoidoscopy, nodular hyperplasia with erosion was observed in 93.3%. Of 27 patients whose mother ate the diet eliminated the 5 food groups, hematochezia diappeared in 74.1% of patients. Offending foods were identified as dairy products (37.5%), wheat and buckwheat (27.5%), fish and shellfish (20.0%), nuts and soybean (7.5%) and eggs (7.5%). A free maternal diet without patient's clinical symptoms was achieved at $29.4{\pm}8.7$ (9~44) weeks of patient's age, and a free baby diet without blood in stools was achieved at $37.5{\pm}9.7$ (12~56) weeks of age. Conclusion: DPIPC commonly occurs in exclusively breast-fed babies. Elimination of the above-mentioned 5 hyper-allergenic food groups from the maternal diet for 7days enables the detection of the offending foods. DPIPC is a transient disorder and 96.0% of patients can tolerate the offending foods at 12 months of age.

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Midterm Patency after Off-Pump Coronary Artery Bypass Grafting (심폐바이패스없이 심박동상태에서 시행한 관상동맥우회술후 중기 개통율)

  • Lee, Cheul;Chang, Woo-Ik;Lim, Cheong;Kim, Ki-Bong;Chae, In-Ho;Oh, Byung-Hee;Lee, Myoung-Mook;Park, Young-Bae
    • Journal of Chest Surgery
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    • v.34 no.8
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    • pp.583-590
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    • 2001
  • The aim of this study was to compare one-year graft patency after coronary artery bypass grafting without cardiopulmonary bypass(OPCAB) with that of conventional CABG and that of on-pump beating CABG, and to demonstrate any differences in patency of various conduits among the three groups. Material and Method: We analyzed the results of OPCAB cases(group I; n=122) compared with those of conventional CABG cases(group II; n=65) and those of on-pump beating CABG cases(group III; n=19). In group I, coronary angiography(CAG) was performed immediately postoperatively and 1 year after surgery. In group II and III, CAG was performed 1 year after surgery. Graft patency was graded as grade A(excellent), grade B(fair), or grade O(occluded). Result: The average number of distal anastomoses in groups I, II, and II were 3.1$\pm$1.1, 3.7$\pm$0.9, and 3.6$\pm$0.9, respectively. In group I, postoperative CAG was performed in 92%(112/122) of patients before discharge. The patency rate(grade A+B) was 96.4$(162/168) for arterial grafts, and 85.6%(160/187) for saphenous vein grafts(SVG). One-year follow-up CAG was performed in 74%(90/122) of patients. The patency rate was 97.8%(132/135) for arterial grafts, and 67.9%(106/156) for SVG. In group II, one-year follow-up CAG was performed in 65%(42/65) of patients. The patency rate(grade A+B) was 93.5%(43/46) for arterial grafts, and 86.8%(33/38) for SVG. Conclusion: Our results demonstrated that the patency rate of SVG after OPCAB was significantly lower than that of arterial grafts in the early postoperative CAG(p<0.001), and was also significantly lower than those of SVG of group II(p<0.001) and group III(p<0.01) in the postoperative one-year CAG, although there was no significant difference is one-year patency of arterial grafts among the three groups. Our data suggest that a specific perioperative anticoagulant therapy may be advisable in patients undergoing OPCAB with SVG.

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THE EFFECT OF IRRADIATION MODES ON POLYMERIZATION AND MICROLEAKAGE OF COMPOSITE RESIN (광조사 방식이 복합레진의 중합과 누출에 미치는 영향)

  • Park, Jong-Jin;Park, Jeong-Won;Park, Sung-Ho;Park, Ju-Myong;Kwon, Tae-Kyung;Kim, Sung-Kyo
    • Restorative Dentistry and Endodontics
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    • v.27 no.2
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    • pp.158-174
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    • 2002
  • The aim of this study was to investigate the effect of light irradiation modes on polymerization shrinkage, degree of cure and microleakage of a composite resin. VIP$^{TM}$ (Bisco Dental Products, Schaumburg, IL, USA) and Optilux 501$^{TM}$ (Demetron/Kerr, Danbury, CT, USA) were used for curing Filtek$^{TM}$ Z-250 (3M Dental Products, St. Paul., MN, USA) composite resin using following irradiation modes: VIP$^{TM}$ (Bisco) 200mW/$\textrm{cm}^2$ (V2), 400mW/$\textrm{cm}^2$ (V4), 600mW/$\textrm{cm}^2$ (V6), Pulse-delay (200 mW/$\textrm{cm}^2$ 3 seconds, 5 minutes wait, 600mW/$\textrm{cm}^2$ 30seconds, VPD) and Optilux 501$^{TM}$ (Demetron/Kerr) C-mode (OC), R-mode (OR). Linear polymerization shrinkage of the composite specimens were measured using Linometer (R&B, Daejeon, Korea) for 90 seconds for V2, V4, V6, OC, OR groups and for up to 363 seconds for VPD group (n=10, each). Degree of conversion was measured using FTIR spectrometer (IFS 120 HR, Bruker Karlsruhe, Germany) at the bottom surface of 2 mm thick composite specimens V2, Y4, V6, OC groups were measured separately at five irradiation times (5, 10, 20, 40, 60 seconds) and OR, VPD groups were measured in the above mentioned irradiation modes (n=5 each). Microhardness was measured using Digital microhardness tester (FM7, Future-Tech Co., Tokyo, Japan) at the top and bottom surfaces of 2mm thick composite specimens after exposure to the same irradiation modes as the test of degree of conversion(n=3, each). For the microleakage test, class V cavities were prepared on the distal surface of the ninety extracted human third molars. The cavities were restored with one of the following irradiation modes : V2/60 seconds, V4/40 seconds, V6/30 seconds, VPD , OC and OR. Microleakage was assessed by dye penetration along enamel and dentin margins of cavities. Mean polymerization shrinkage, mean degree of conversion and mean microhardness values for all groups at each time were analyzed using one-way ANOVA and Duncan's multiple range test, and using chi-square test far microleakage values. The results were as follows : . Polymerization shrinkage was increased with higher light intensity in groups using VIP$^{TM}$ (Bisco) : the highest with 600mW/$\textrm{cm}^2$, followed by Pulse-delay, 400mW/$\textrm{cm}^2$ and 200mW/$\textrm{cm}^2$ groups, The degree of polymerization shrinkage was higher with Continuous mode than with Ramp mode in groups using Optilux 501$^{TM}$ (Demetron/Kerr). . Degree of conversion and microhardness values were higher with higher light intensity. The final degree of conversion was in the range of 44.7 to 54.98% and the final microhardness value in the range of 34.10 to 56.30. . Microleakage was greater in dentin margin than in enamel margin. Higher light intensity showed more microleakage in dentin margin in groups using VIP$^{TM}$ (Bisco). The microleakage was the lowest with Continuous mode in enamel margin and with Ramp mode in dentin margin when Optilux 501$^{TM}$ (Demetron/Kerr) was used.

The Role of c-Jun N-terminal Kinase in the Radiation-Induced Lung Fibrosis (방사선에 의한 폐 섬유화증에서 c-Jun N-terminal Kinase(JNK)의 역할)

  • Uh, Soo-Taek;Hong, Ki-Young;Lee, Young-Mok;Kim, Ki-Up;Kim, Do-Jin;Moon, Seung-Hyuk;Kim, Yong-Hoon;Park, Choon-Sik;Yeom, Uk;Kim, Eun-Suk;Choi, Doo-Ho
    • Tuberculosis and Respiratory Diseases
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    • v.50 no.4
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    • pp.450-461
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    • 2001
  • Background : The underlying pathogenesis of radiation-induced lung fibrosis (RTLF) has not been very well defined. However, the role of TGF-$\beta$ in the generation of RTLF has been a major focus because there is an increase in the expression of both the TGF-${\beta}m$-RNA and its protein preceding RTLF lesions. The down stream signal after a TGF-$\beta$ stimulated lung fibrosis includes the activation of many mediators such as Smad and c-Jun N-terminal kinase (JNK) through TAK1. It is we hypothesized that JNK activation may play a pivotal role in RTLF pathogenesis through increased transcription of the fibrogenic cytokines. The present study evaluates JNK activity in alveolar macrophages after irradiation and the relationship between JNK activity and the amount of collagen in the lung tissues. Methods : C57BL/6 mice(20-25 gr, males) received chlorotetracycline(2g/L) in their drinking water 1 week prior to irradiation and continuously there after. The mice were irradiated once with 1400 cGy of $60CO{\gamma}$-ray over the whole chest. The cellular composition of the whole lung bronchoalveoalr lavage fluids(BALF), elastin expression in the lung tissues, the level of hydroxyproline in lung tissues, and an in vitro JNK assay was measured before irradiation and one, four, and eight weeks after irradiation (RT). Results : The volumes of BALF retrieved from instilled 4 mL of saline with 2% heparin were 3.7-3.8 mL for each group. The cell numbers were similar before($4.1{\times}10^4{\pm}0.5{\times}10^4/mL$) and 1 week($3.1{\times}10^4{\pm}0.5{\times}10^4/mL$) after RT. At four and eight weeks after RT, the cell number reached to $14.0{\times}10^4{\pm}1.5{\times}10^4mL$ and $10.0{\times}10^4{\pm}1.3{\times}10^4/mL$, respectively. There we no changes in the lymphocytes and neutrophils population observed in the BALF after RT. The H-E stain of the lung tissues did not show any structural and fibrotic change in the lung tissues at 4 and 8 weeks after RT. In addition, the amount of elastin and collagen were not different on Verhoeff staining of the lung tissues before RT to eight weeks after RT. The hydroxyproine content was measured with the left lung dissected from the left main bronchus. The lung were homogenized and hydrolyzed with 6 N Hel for 12 hours at $110^{\circ}C$ then measured as previously described. The content of hydroxyproline, standardized with a lung protein concentration, reached a peak 4 weeks after RT, and thereafter showed a plateau. AnIn vitro JNK assay using c-$Jun_{1-79}$-GST sepharose beads were performed with the alveolar macrophages obtained from the BAL. JNK activity was not detected prior to RT, However, the JNK activity increased from one week after RT and reached a peak four weeks after RT. Conclusion : JNK may be involved in the pathogenesis because the JNK activity showed similar pattern observed with the hydroxyproine content. However, it is necessary to clarify that the JNK increases the transcription of fibrogenic cyiokines through the transcription factor.

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