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Regulatory Mechanism of Insulin-Like Growth Factor Binding Protein-3 in Non-Small Cell Lung Cancer (비소세포성 폐암에서 인슐린 양 성장 인자 결합 단백질-3의 발현 조절 기전)

  • Chang, Yoon Soo;Lee, Ho-Young;Kim, Young Sam;Kim, Hyung Jung;Chang, Joon;Ahn, Chul Min;Kim, Sung Kyu;Kim, Se Kyu
    • Tuberculosis and Respiratory Diseases
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    • v.56 no.5
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    • pp.465-484
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    • 2004
  • Background : Insulin-like growth factor (IGF)-binding protein-3 (IGFBP-3) inhibits the proliferation of non-small cell lung cancer (NSCLC) cells by inducing apoptosis. Methods : In this study, we investigated whether hypermethylation of IGFBP-3 promoter play an important role in the loss of IGFBP-3 expression in NSCLC. We also studied the mechanisms that mediate the silencing of IGFBP-3 expression in the cell lines which have hypermethylated IGFBP-3 promoter. Results : The IGFBP-3 promoter has hypermethylation in 7 of 15 (46.7%) NSCLC cell lines and 16 (69.7%) of 23, 7 (77.8%) of 9, 4 (80%) of 5, 4 (66.7 %) of 6, and 6 (100%) of 6 tumor specimens from patients with stage I, II, IIIA, IIIB, and IV NSCLC, respectively. The methylation status correlated with the level of protein and mRNA in NSCLC cell lines. Expression of IGFBP-3 was restored by the demethylating agent 5'-aza-2'-deoxycytidine (5'-aza-dC) in a subset of NSCLC cell lines. The Sp-1/ Sp-3 binding element in the IGFBP-3 promoter, important for promoter activity, was methylated in the NSCLC cell lines which have reduced IGFBP-3 expression and the methylation of this element suppressed the binding of the Sp-1 transcription factor. A ChIP assay showed that the methylation status of the IGFBP-3 promoter influenced the binding of Sp-1, methyl-CpG binding protein-2 (MeCP2), and histone deacetylase (HDAC) to Sp-1/Sp-3 binding element, which were reversed by by 5'-aza-dC. In vitro methylation of the IGFBP-3 promoter containing the Sp-1/Sp-3 binding element significantly reduced promoter activity, which was further suppressed by the overexpression of MeCP2. This reduction in activity was rescued by 5'-aza-dC. Conclusion : These findings indicate that hypermethylation of the IGFBP-3 promoter is one mechanism by which IGFBP-3 expression is silenced and MeCP2, with recruitment of HDAC, may play a role in silencing of IGFBP-3 expression. The frequency of this abnormality is also associated with advanced stages among the patients with NSCLC, suggesting that IGFBP-3 plays an important role in lung carcinogenesis/progression and that the promoter methylation status of IGFBP-3 may be a marker for early molecular detection and/or for monitoring chemoprevention efforts.

A Study on the Illumination of Household and Research on the Actual Conditions of Wearing Spectacles in Dwellers (주택의 조명과 거주자의 면경착용 실태조사연구)

  • 석호작;남철현
    • Journal of Environmental Health Sciences
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    • v.17 no.2
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    • pp.54-66
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    • 1991
  • As a result of measuring illumination and making up a question at home visit directly by investigator who trained over twenty days period from October 4 to 24, 1990, in order to render help which illumination problem against house, society against eyes or framing of health instruction potgram by seizing natural lighting actual conditions of house and actual conditions of wearing spectacles and by investigating interrelationship, I can summarize as follows. 1) In property of investigation subject, woman 66.9%, In an age, the twenties was largest of 27.4%, the forties was 20.2%, the fifties was 18.6%, the thirties was 17.4%. In academic career, those of upper secondary school grauates was largest of 28.6%, those who possess university career was 25.9%, those who middle school career was 20.9%, decoding of Korean alphabet was 2%. 2) By a residence area, a big city was 43.3%, farming and fishing villages were 20.3%, the rest was a small town and the administrative office of town, township. In positon of house, the middle area was 43.6%, resident of suburb area was 38.0%. In form of house, a Korean-style house was 40.8%, a western-style house was 34.8%, an apartment house was 11.0%. In the a standard of living, the middle classes 77.2%, the lower classes were 15.3%. In residential house unit of area, from 21 to 30 unit of area was largest of 31.5%, from 10 to 20 unit of area was 19.9%, from 31 to 40 was 18.7%. 3) The wearing spectacles rate of study user was 44.1%. By the area, those who wearing spectacles was more than a half of 50.8% in the resident of big city area. As passing from the farm area to the city, that is being resident of big city was high wearing spectacles rate. In position of house, as being residence in central street showed high wearing spectacles rate. (central street was 51.5%, the middle area was 44.5% and the suburb area was 40.1%.) It seemed similarity difference a variable by position of house from wearing spectacles in standard of 1%. By form of house, wearing spectacles rate those who resident in apartment house was 49.5%, that rate those who resident in a western-style house was high of 49.0%, that rate those who resident in a Korean-style house was the lowest 39.0%. By social position of resident in room, in students case who study showed very high, as university students were very high of 62.3% idn wearing spectacles rate, middle and high school students 'were 50.0%, members of society were 47.6%, workers 20.3%. It seemed similarity difference from academic career in standard of 1%. By an age, the thirties was high of 54.1% in wearing spectacles rate, the twenties was 43.2%, the teenage was the lowest of 11.8%. 4) In illumination of study, over 200Lux was high of 40.1%. but below 99Lux which inappropriate illumination to see the books was 32.4%. Average by area, below 99Lux was 22.7% and over 400Lux was 50.0% in case of wooden floor. As examine by area, below 99Lux was high of 27.0% a case of wooden floor in the big city area, it was not good in illumination passing from the farm area(15.0%) to the city(19.0%). Average illlumination by area of the main living room below 99Lux was high of 37.5%, less than 200Lux was 58.5% of whole. In general, illumination of the main livingroom was inappropriate. By area, the big city was 32.5% below 99Lux, the middle and small city area were 33.8%, town and township area were 45.0%, farming and fishing area were 42.8%. By area, in the big city, illumination of study was 52.5% over 200Lux and 28.9% below 99Lux. In case of the middle and small city, study user of below 99Lux was 38.8% and over 200Lux was 46.9%. In case of the seat of town township, below 99Lux was 34.1% and over 200Lux was 39.7%. In case of farming and fishing area, illumination of study was 33.4% below 99Lux and 48.4% over 200Lux. It tends to high rate of inappropriate illumination. 5) By position of house, in case of wooden floor, less than 100Lux was 24.5% in central street. It was bad illumination than others position of house. In case of the main livingroom, less than 100Lux was 40.4% in the suburb area. It was bad iliumnation than others position of house. In case of study, less than 100Lux was 35.4% in the middle area, it was worse in illumination. In case of the main living room, is seemed similarity difference in standard of 1%. 6) By form of house, in case of wooden floor, illumination of less than 100Lux was 23.8% in a western-style house, it was bad illumination than others form of house. In case of the main livingroom, illumination of less than 100Lux was 47.4% in a Korean-style house, it was remarkably bad illumination than others form of house. In case of study, a Korean-style house was 38.8%, it was very bad illumination than others form of house. In case of the main livingroom and study, it seemed similatrity difference each as P < 0.01 and P < 0.05 in standard of 1%. 7) The wearing spectacles rate of those who use room of illumination over 400Lux was 40.7%, and that of those who use room of illumination less than 100Lux was 28.1%. It seemed similarity differecce in standard of 1%. 8) In period of wearing spectacles, 21.3% of total investigator-highest-was from before five years, 8.6% was from before three years. Among those who use of illumintion less than 99Lux, 34.0% began to wear spectacles from before two years 31.7% was from before five years, 30.3% was from before four years. It seemed similarity difference from period of wearing spectacles by illumination in standard of 1 %. 9) Among cause which sight grow worse, the first was that it was each 33.2% and 27.4% in response rate because watch TV nearly to wearing spectacles person and non-wearing person. The second was that a lot of seeing books was 25.3% in wearing spectacles person and response rate for dark illumination was 7.4% in nonwearing spectacles person. It seemed similarity difference in standard of 1%. (P < 0.01). 10) In experience which take medicine good for eyes, it was 50.1% in wearing spectacles person and 8.5% in non-wearing spectacles person. It seemed similarity difference in standard of 1%(P < 0.01). As we have seen above, inappropriate illumination can be a cause of wearing spectacles. Nevertheless, actually, is realities to indifferent against illumination of house. So it must learn knowledge about health obstacle of illumination through society instruction and school eduction against students as well as general residents. In case that natural lighting is inappropriate structural of house, we must be able to maintain appropriate illumination through artificial illumination. And so eyes which is core of human life have to be protected, related the authorities, related group, and all health medical personnel will organically cooperate with and make efforts.

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The effects of fluoride releasing orthodontic sealants on the prevention and the progressive inhibition of enamel demiheralization in vitro (광중합형 및 자가중합형 교정용 전색제의 치아우식예방 및 진행억제효과에 관한 실험적 연구)

  • Chae, Seung-Won;Cho, Jae-O;Yoon, Young-Jooh;Kim, Kwang-Won
    • The korean journal of orthodontics
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    • v.27 no.6 s.65
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    • pp.979-995
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    • 1997
  • The purpose of this study was to identify the preventive and the progressive inhibitory effects of enamel demineralization with fluoride releasing light-and self-cured orthodontic sealants(FluoroBond), in vitro, under the polarizing light microscope and the scanning electon microscope. The polarizing light microscopic group was subdivided into seven groups(Group A-Group G). The scanning electron microscopic group was also subdivided into seven groups(Group A'-Goup G'). For polarizing light microscopic evaluation, longitudinal sections were made longitudinally by Maruto cutter(Maruto Co., Japan) and Maruto grinding machine(Maruto Co., Japan). Sections were examined and photographed by the polarizing light microscope(Olympus Optical Co., Japan) using crossed polars and with the enamel rod longitudinal axis oriented at $45^{\circ}$ to the extinction position. For scanning electron microscopic evaluation, the specimens were coated with a highly conducting layer of gold palladium in a model Hus-4 high-vacuum evaporator and examined in an ISI-100B scanning electron microcope operated at 20kV. The results of this study were as follows : 1. The mean depths of artificial carious lesions under a polarized light microscope were $Group\;A(5.08{\mu}m),\;Group\;B(47.82{\mu}m,\;Group\;C(8.42{\mu}m),\;Group\;D(7.20{\mu}m),\;Group\;E(85.41{\mu}m),\;Group\;F(60.38{\mu}m),\;Group\;G(60.13{\mu}m)$. 2. There were statistically significant differences in Group B compared with Group A, C, and D(p<0.05), and also, in Group I compared with Group F and Group G(p<0.05). 3. Light-and self-cured orthodontic sealants had the preventive effects of enamel demineralization. 4. Light-and self-cured orthodontic sealants had the progressive inhibitory effects of enamel demineralization. 5. The time progress of demineralizing agent had no influence on the samples of light-and self-cured orthodontic sealants under the scanning electron microscope. 6. There was no difference between the specimens of light-and self-cured orthodontic sealants both in the polarized light microscopic group and in the scanning electron microscopic group.

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Studies on the Cold Resistance of The tea Plant in Korea -Especially on Leaf form and Cold resistance (한국산다수(韓國産茶樹)의 내한성(耐寒性)에 관(關)한 연구(研究) -특(特)히 지역별(地域別) 엽형태(葉形態)와 내한성(耐寒性)을 중심(中心)으로)

  • Kim, Jai Saing;Kim, Chang Ho
    • Journal of Korean Society of Forest Science
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    • v.53 no.1
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    • pp.37-43
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    • 1981
  • This study was aimed at expanding the tea plant culture in Korea to further north, and the leaf-form and the cold resistance of the tea plants selected form 7 districts(around Korea) were investigated. 1. The length of tea leaf is 5.1cm to 8.4cm, the width of the leaf is 2.3cm to 3.6cm, but the area of tea leaf in Mt. Mudung is $26.88cm^2$ and that is the widest of all. 2. The tooth number of the tea leaf in 43 to 73 but the number of Mt. Borim is remarkably number of all. The tooth number is increased or decreased in proportion to the leaf width and to the leaf length. 3. The lateral vein number is generally 13 to 19. The vein number of Mt. Borim is especially number of all. That is also increased or decreased in proportion to the leaf width and to the leaf length. 4. In general, the number of leaf formation index is 2 to 3, and ablong. 5. In general, those which come upper lands are remarkably small in length and width of the tea leaf and those which come from level lands are large. 6. All kinds of tea plant which is growing in Korea, area, are the same as those imported from China : Thea sinensis Linne var. Bohea. 7. I supposed that the external form of tea plant has a little changed by geography or climate for many a long day, since the tea plant had been transplanted in Mt. Samsin. 8. In the treatment of low temperature and duration of vernalization of their plants, those selected from Mt. Mudung and Mt. Hwaun were the coldest resistance, those from Mt. Samsin and Mt. Borim were medium and those from Mt. Joge and Nursery were cold sensitive. 9. The critical temperature of the tea plant from Mt. Mudung, Mt, Hwaum, Mt, Samsin and Mt. Borim was about $-10^{\circ}C$, and that from Mt. Joga and Nursery was about $-5^{\circ}C$. The critical temperature of frost injury of all tea plants in this experiments was $-15^{\circ}C$. 10. In spite of increasing the vernalization time, the critical temperature was not effected, but the treatments over critical temperature were increased their frost injuries. Based on these results, the coldest resistance, Mt. Mudung tea plant, was considered expanding their culture to further north improvement yields of the tea plants in Korea.

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Studies on Ancylostomiasis I. An Experimental Study on Hookworm Infection and Anemia (구충증(鉤蟲症)에 관(關)한 연구(硏究) 제1편(第1篇) 구충(鉤蟲)의 감염(感染) 및 구충성빈혈(鉤蟲性貧血)에 관(關)한 고찰(考奈))

  • Lee, Mun-Ho;Kim, Dong-Jip;Lee, Jang-Kyu;Seo, Byong-Sul;Lee, Soon-Hyung
    • The Korean Journal of Nuclear Medicine
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    • v.1 no.1
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    • pp.55-66
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    • 1967
  • In view of its prevalence in the Far East area, a more detailed knowledge on the hookworm infection is one of the very important medical problems. The present study was aimed to; determine the infectivity of the artificially hatched ancylostoma duodenale larvae in man after its oral administration, evaluate the clinical symptomatology of such infection, determine the date of first appearance of the ova in the stool, calculate the blood loss per worm per day, assess the relation-ships between the ova count, infectivity(worm load), blood loss and severity of anemia. An erythrokinetic study was also done to analyse the characteristics of hookworm anemia by means of $^{59}Fe\;and\;^{51}Cr$. Materials and Methods Ten healthy male volunteers(doctors, medical students and laboratory technicians) with the ages ranging from 21 to 40 years were selected as the experimental materials. They had no history of hookworm infection for preceding several years, and care was taken not to be exposed to reinfection. A baseline study including a through physical examinations and laboratory investigations such as complete blood counts, stool examination and estimation of the serum iron levels was done, and a vermifuge, bephenium hydroxynaphoate, was given 10 days prior to the main experiment. The ancylostoma duodenale filariform larvae were obtained in the following manner; The pure ancylostoma duodenale ova were obtained from the hookworm anemia patients and a modified filter paper method was adopted to harvest larger number of infective larvae, which were washed several times with saline. The actively moving mature larvae were put into the gelatine capsules, 150 in each, and were given to the volunteers in the fasting state with 300ml. of water. The volunteers were previously treated with intramuscular injection of 15mg. of chlorpromazine in order to prevent the eventual nausea and vomiting after the larvae intake. The clinical symptoms and signs mainly of the respiratory and gastrointestinal tracts, appearance of the ova and occult blood in the stool etc. were checked every day for the first 20 days and then twice weekly until the end of the experiment, which usually lasted for about 3 months. Roentgenological survey of the lungs was also done. The hematological changes such as the red blood cell, white blood cell and eosinophil cell counts, hemoglobin content and serum iron levels were studied. The appearance of the ova in the stool was examined by the formalin ether method and the ova were counted in triplicate on two successive days using the Stoll's dilution method. The ferrokinetic data were calculated by the modified Huff's method and the apparent half survival time of the red blood cells by the modified Gray's method. The isotopes were simultaneously tagged and injected intravenously, and then the stool and blood samples were collected as was described by Roche et al., namely, three separate 4-day stool samples with the blood sample drawing before each 4-day stool collection. The radio-activities of the stools ashfied and the blood were separately measured by the pulse-height analyser. The daily blood loss was calculated with the following formula; daily blood loss in $ml.=\frac{cpm/g\;stool{\times}weight\;in\;g\;of\;4-day\;stool}{cpm/ml\;blood{\times}4}$ The average of these three 4-day periods was given as the daily blood loss in each patient. The blood loss per day per worm was calculated by simply dividing the daily blood loss by the number of the hookworm recovered after the vermifuge given twice a week at the termination of the experiment. The iron loss in mg. through the gastrointestinal tract was estimated with the daily iron loss in $mg=\frac{g\;Hgb/100ml{\times}ml\;daily\;blood\;loss{\times}3.40}{100}$ 3.40=mg of iron per g Hgb following formula; Results 1. The respiratory symptoms such as cough and sputum were noted in almost all cases within a week after the infection, which lasted about 2 weeks. The roentgenological findings of the chest were essentially normal. A moderate degree of febril reaction appeared within 2 weeks with a duration of 3 or 4 days. 2. The gastrointestinal symptoms such as nausea, epigastric fullness, abdominal pain and loose bowel appeared in all cases immediately after the larvae intake. 3. The reduction of the red blood cell count was not remarkable, however, the hemoglobin content and especially the serum iron level showed the steady decreases until the end of the experiment. 4. The white blood cells and eosinophil cells, on the contrary, showed increases in parallel and reached peaks in 20 to 30 days after the infection. A small secondary rise was noted in 2 months. 5. The ova first appeared in the stool in 40. 1 days after the infection, ranging from 29 to 51 days, during which the occult blood reaction of the stool became also positive in almost cases. 6. The number of ova recovered per day was 164, 320 on the average, ranging from 89,500 to 253,800. The number of the worm evacuated by vermifuge was in rough correlation with the number of ova recovered. 7. The infectivity of ancylostoma duodenale was 14% on the average, ranging from 7.3 to 20.0%, which is relatively lower than those reported by other workers. 8. The mean fecal blood loss was 5.78ml. per day, with a range of from 2.6 to 11.7ml., and the mean blood loss per worm per day was 0.30ml., with a range of from 0.13 to 0.73ml., which is in rough coincidence with those reported by other authors. There appeared to exist, however, no correlation between the blood loss and the number of ova recovered. 9. The mean fecal iron loss was 2.02mg. per day, with a range of from 1.20 to 3.89mg., which is less than those appeared in the literature. 10. The mean plasma iron disappearance rate was 0.80hr., with a range of from 0.62 to 0.95hr., namely, a slight accerelation. 11. The hookworm anemia appeared to be iron deficiency in origin caused by continuous intestinal blood loss.

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Radiosynthesis of $[^{11}C]6-OH-BTA-1$ in Different Media and Confirmation of Reaction By-products. ($[^{11}C]6-OH-BTA-1$ 조제 시 생성되는 부산물 규명과 반응용매에 따른 표지 효율 비교)

  • Lee, Hak-Jeong;Jeong, Jae-Min;Lee, Yun-Sang;Kim, Hyung-Woo;Lee, Eun-Kyoung;Lee, Dong-Soo;Chung, June-Key;Lee, Myung-Chul
    • Nuclear Medicine and Molecular Imaging
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    • v.41 no.3
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    • pp.241-246
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    • 2007
  • Purpose: $[^{11}C]6-OH-BTA-1$ ([N-methyl-$^{11}C$]2-(4'-methylaminophenyl)-6-hydroxybenzothiazole, 1), a -amyloid imaging agent for the diagnosis of Alzheimer's disease in PET, can be labeled with higher yield by a simple loop method. During the synthesis of $[^{11}C]1$, we found the formation of by-products in various solvents, e.g., methylethylketone (MEK), cyclohexanone (CHO), diethylketone (DEK), and dimethylformamide (DMF). Materials and Methods: In Automated radiosynthesis module, 1 mg of 4-aminophenyl-6-hydroxybenzothiazole (4) in 100 l of each solvent was reacted with $[^{11}C]methyl$ triflate in HPLC loop at room temperature (RT). The reaction mixture was separated by semi-preparative HPLC. Aliquots eluted at 14.4, 16.3 and 17.6 min were collected and analyzed by analytical HPLC and LC/MS spectrometer. Results: The labeling efficiencies of $[^{11}C]1$ were $86.0{\pm}5.5%$, $59.7{\pm}2.4%$, $29.9{\pm}1.8%$, and $7.6{\pm}0.5%$ in MEK, CHO, DEK and DMF, respectively. The LC/MS spectra of three products eluted at 14.4, 16.3 and 17.6 mins showed m/z peaks at 257.3 (M+1), 257.3 (M+1) and 271.3 (M+1), respectively, indicating their structures as 1, 2-(4'-aminophenyl)-6-methoxybenzothiazole (2) and by-product (3), respectively. Ratios of labeling efficiencies for the three products $([^{11}C]1:[^{11}C]2:[^{11}C]3)$ were $86.0{\pm}5.5%:5.0{\pm}3.4%:1.5{\pm}1.3%$ in MEK, $59.7{\pm}2.4%:4.7{\pm}3.2%:1.3{\pm}0.5%$ in CHO, $9.9{\pm}1.8%:2.0{\pm}0.7%:0.3{\pm}0.1%$ in DEK and $7.6{\pm}0.5%:0.0%:0.0%$ in DMF, respectively. Conclusion: The labeling efficiency of $[^{11}C]1$ was the highest when MEK was used as a reaction solvent. As results of mass spectrometry, 1 and 2 were conformed. 3 was presumed.

Protective Effect of Plantago asiatica L. Leaf Ethanolic Extract Against Ferric Nitrilotriacetate-Induced Prostate Oxidative Damage in Rats (랫드에서의 Fe-NTA 유발 산화스트레스에 대한 차전초 에탄올 추출물의 전립선보호 효과)

  • Hong, Seung-Taek;Hong, Chung-Oui;Nam, Mi-Hyun;Ma, Yuan-Yuan;Hong, Yun-Jin;Son, Da-Hee;Chun, Su-Hyun;Lee, Kwang-Won
    • Journal of Food Hygiene and Safety
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    • v.26 no.3
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    • pp.260-265
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    • 2011
  • Plantago asiatica L. (P. asiatica) has been used as one of the popular folk medicines in Asia for human health care practices. Various activities of P. asiatica have been reported, such as anti-oxidant, anti-glycation, anti-inflammatory and hepatoprotective activity. Therefore, the potential of P. asiatica to reduce oxidative stress has been studied in several ways for over 20 years, especially at liver and kidney. However no investigation has been reported revealing its protective effect on prostate. Method: Treatment of P. asiatica leaf ethanolic extract (PLE) (1 g/kg body weight (b.w.), 2 g/kg b.w., or 4 g/kg b.w.) were given separately to animals for pretreatment once per day for 7 days, and on the seventh day ferric nitrilotriacetate (Fe-NTA; 0.24 mmol Fe/kg b.w.), which is known as an oxidative stress-inducer at prostate, was administrated by i.p to negative control group. At the end of the study period, dissection was carried out for detecting the prostate protective effect of PLE. Result: Fe-NTA-treated animals produced reactive oxygen species (ROS) resulting in depletion of antioxidant biomaker, such as glutathione (GSH), glutathione reductase (GR), and glutathione s-transferase (GST) and increase of lipid peroxidation in prostate. However, PLE pretreatment resulted in an increase in the GSH, GST and GR levels concentration dependent manner and in an significant decrease in the levels of lipid peroxidation. Conclusion: Our data suggest that PLE may be effective in protecting oxidative stress-induced damage of prostate, and PLE may be an chemopreventive agent against Fe-NTA-mediated prostate oxidative damage.

Preparation of Pure CO2 Standard Gas from Calcium Carbonate for Stable Isotope Analysis (탄산칼슘을 이용한 이산화탄소 안정동위원소 표준시료 제작에 대한 연구)

  • Park, Mi-Kyung;Park, Sunyoung;Kang, Dong-Jin;Li, Shanlan;Kim, Jae-Yeon;Jo, Chun Ok;Kim, Jooil;Kim, Kyung-Ryul
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.18 no.1
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    • pp.40-46
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    • 2013
  • The isotope ratios of $^{13}C/^{12}C$ and $^{18}O/^{16}O$ for a sample in a mass spectrometer are measured relative to those of a pure $CO_2$ reference gas (i.e., laboratory working standard). Thus, the calibration of a laboratory working standard gas to the international isotope scales (Pee Dee Belemnite (PDB) for ${\delta}^{13}C$ and Vienna Standard Mean Ocean Water (V-SMOW) for ${\delta}^{18}O$) is essential for comparisons between data sets obtained by other groups on other mass spectrometers. However, one often finds difficulties in getting well-calibrated standard gases, because of their production time and high price. Additional difficulty is that fractionation processes can occur inside the gas cylinder most likely due to pressure drop in long-term use. Therefore, studies on laboratory production of pure $CO_2$ isotope standard gas from stable solid calcium carbonate standard materials, have been performed. For this study, we propose a method to extract pure $CO_2$ gas without isotope fractionation from a solid calcium carbonate material. The method is similar to that suggested by Coplen et al., (1983), but is better optimized particularly to make a large amount of pure $CO_2$ gas from calcium carbonate material. The $CaCO_3$ releases $CO_2$ in reaction with 100% pure phosphoric acid at $25^{\circ}C$ in a custom designed, evacuated reaction vessel. Here we introduce optimal procedure, reaction conditions, and samples/reactants size for calcium carbonate-phosphoric acid reaction and also provide the details for extracting, purifying and collecting $CO_2$ gas out of the reaction vessel. The measurements for ${\delta}^{18}O$ and ${\delta}^{13}C$ of $CO_2$ were performed at Seoul National University using a stable isotope ratio mass spectrometer (VG Isotech, SIRA Series II) operated in dual-inlet mode. The entire analysis precisions for ${\delta}^{18}O$ and ${\delta}^{13}C$ were evaluated based on the standard deviations of multiple measurements on 15 separate samples of purified $CO_2$. The pure $CO_2$ samples were taken from 100-mg aliquots of a solid calcium carbonate (Solenhofen-ori $CaCO_3$) during 8-day experimental period. The multiple measurements yielded the $1{\sigma}$ precisions of ${\pm}0.01$‰ for ${\delta}^{13}C$ and ${\pm}0.05$‰ for ${\delta}^{18}O$, comparable to the internal instrumental precisions of SIRA. Therefore, we conclude the method proposed in this study can serve as a way to produce an accurate secondary and/or laboratory $CO_2$ standard gas. We hope this study helps resolve difficulties in placing a laboratory working standard onto the international isotope scales and does make accurate comparisons with other data sets from other groups.

Analysis of Urinary Mass Screening for Elementary, Middle and High School Children Over a 3-year Period(1995-1997) in Seoul (서울지역내 초.중.고 학생들에 실시된 3년 동안의($1995{\sim}1997$) 집단뇨검사 결과 분석)

  • Kang Ho-Seok;Lee Chong-Guk
    • Childhood Kidney Diseases
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    • v.3 no.2
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    • pp.161-169
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    • 1999
  • Purpose : The urinary mass screening program for the detection of proteinuria in school aged population has been performed in Seoul since 1981. Systematic evaluation in corporation with the Seoul School Health Center for students with proteinuria identified in the mass screening has been performed from 1987. The results of urinary mass screening up to 1994 was reported. I report here the results of urinary mass screening from 1995 to 1997 and compare them with previous results and attempt to reveal the significance of urinary mass screening. Objects and Methods : In the 3-year period between 1995 and 1997, annually about 460,000 students comprising 3 different age groups; 5th grade of elementary school, 2nd grade of middle school and 2nd grade of high school were chosen, corresponding to the approximate ages of 11, 14, and 17 years, respectively. These subjects accounted for 26% of total school aged children in Seoul. The screening program was carried out in 3 steps. The 1st test was performed with dipstick at school and the 2nd at the Seoul School Health Center. Those students who showed proteinuria in the 1st and 2nd tests were referred to the hospital. Laboratory examinations including renal biopsies were performed to those students with pathologic proteinuria to clarify the incipient renal diseases. Results : 1) The prevalence of asymptomatic proteinuria was 0.28% in the 1st test. It peaked at the group of 14 years old as 0.34%, compared with 0.26% at the group of 11 years old and 0.24% at the group of 17 years old. It reached to 0.26% in male and 0.30% in female. 2) 25 percent of those having proteinuria at the first test were positive at the second test. 3) The proportion of patients with proteinuria by 3rd test were as follows; 25% of transient proteinuria, 55% of orthostatic proteinuria, 6% of constant proteinuria, 12% of proteinuria with hematuria, and 2% of transient proteinuria with isolated hematuria. Pathologic proteinuria were totaled as 20%. The prevalence of renal diseases among the age group of 7-18 years old was estimated to be 1.4 per 10,000. 4) Renal biopsy performed on 38 children with proteinuria at the third test revealed IgA nephropathy in 17(44%), focal segmental glomerusclerosis in 5(13%), minimal change disease in 4(11%), membranoproliferative glomeronephritis in 3(8%), $Henoch-Sch\"{o}nlein$ purpura nephritis in 3(8%), and others in 6(16%). Therefore, the prevalence of IgA nephropathy among the age group of 7-18 years old was estimated to be 0.64 per 10,000. 5) The prevalence of chronic renal failure was estimated to be 5.7 per 1 million of 7 to 18 years age group. Conclusions : 1) The prevalence of proteinuria in the first screening test was 0.28% and finally only 5% of them showed the pathologic proteinuria at the third test. 2) The prevalence of IgA nephropathy and chronic renal failure were 0.63 per 10,000 and 5.7 per 1 million, respectively among school-aged children in Seoul.

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Soil amendment for turfgrass vegetation of the Incheon International Airport runway side on the Yeongjong reclaimed land (인천국제공항 착륙대 잔디 식재 지반 조성을 위한 영종도 매립 토양 개량)

  • Yoo, Sun-Ho;Jeong, Yeong-Sang;Joo, Young-Kyu;Choi, Byung-Kwon;Wu, Heun-Young;Lee, Tae-Young
    • Korean Journal of Soil Science and Fertilizer
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    • v.35 no.2
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    • pp.93-104
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    • 2002
  • A field survey and experiment was conducted from 1996 to 1998 to develop rational technology for turfgrass vegetation of runway side of Incheon International Airport on the reclaimed tidal land in Young-Jong Island. Backfill of the experimental site was finished on August 1995. The experimental site was 8 ha located in the middle of the construction place for the main parking lot in front of the terminal building construction. The experimental field was drained by main open ditch, and divided three main plots, no subsurface tile drain, subsurface tile drain spacing with 22.5m, and with 45 m, respectively. The 17 sub plots were designed to test the effect of soil covering with red earth loam by 5 cm and 20 cm depth, application of chemical compound fertilizers and livestock manures, dressing of artifical soils and hydrophylic soil conditioners. The tested turfgrasses were three transplanting indigenous turfgrasses, Zoysia koreana, Zoysia sinica and Zoysia japonica, and two hydroseeding mixed exotic turgrasses, cool type I(tall fescue 30%, kentucky blue grass 40%, perenial ryegrass 30%), and cool type II(tall fescue 40%, perenial ryegrass 20%, fine fescue 20%, alkaligrass 20%). The soil backfilled with dredged seasand was sand textured with high salt concentration and low fertility. The soil showed high pH, low organic matter and low available phophate contents. The percolation rate was fast with high hydraulic conductivity. Desalinization was fast after installation of the main open drainage system. No subsurface tile drainage effect was found showing little difference in turfgrass growth. The covering and visual growth of turfgrasses were the best in the 20-cm soil covering with compound fertilizer treatment. The covering and visual growth of turfgrasses were satisfactory in the 5 cm soil covering with compound fertilizer treatment and with livestock manure treatments. The hydrophillic soil conditioner treatments were effective but expensive at present. The coverage and visual quality of turfgrasses were good for Zoysia koreana and Zoysia japonica. The coverages of turfgrasses by the hydroseeding with the mixed exotic turfgrasses were less than transplanting of native turfgrasses. In conclusion, for the runway side vegetation purposes, the subsurface tile drainage might not necessary as main open ditch drainage be sufficient due to fast percolation rate of the backfilled dredged seasand. The 5 cm soil covering with red earth might be sufficient for the runway side, but the 20 cm soil covering might be necessary for the runway side where high density of turfgrass coverage was necessary to protect from the airplance air blow.