• Title/Summary/Keyword: Head growth

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How Can Non.Chaebol Companies Thrive in the Chaebol Economy? (비재벌공사여하재재벌경제중생존((非财阀公司如何在财阀经济中生存)? ‐공사층면영소전략적분석(公司层面营销战略的分析)‐)

  • Kim, Nam-Kuk;Sengupta, Sanjit;Kim, Dong-Jae
    • Journal of Global Scholars of Marketing Science
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    • v.19 no.3
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    • pp.28-36
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    • 2009
  • While existing literature has focused extensively on the strengths and weaknesses of the Chaebol and their ownership and governance, there have been few studies of Korean non-Chaebol firms. However, Lee, Lee and Pennings (2001) did not specifically investigate the competitive strategies that non-Chaebol firms use to survive against the Chaebol in the domestic Korean market. The motivation of this paper is to document, through four exploratory case studies, the successful competitive strategies of non-Chaebol Korean companies against the Chaebol and then offer some propositions that may be useful to other entrepreneurial firms as well as public policy makers. Competition and cooperation as conceptualized by product similarity and cooperative inter.firm relationship respectively, are major dimensions of firm.level marketing strategy. From these two dimensions, we develop the following $2{\times}2$ matrix, with 4 types of competitive strategies for non-Chaebol companies against the Chaebol (Fig. 1.). The non-Chaebol firm in Cell 1 has a "me-too" product for the low-end market while conceding the high-end market to a Chaebol. In Cell 2, the non-Chaebol firm partners with a Chaebol company, either as a supplier or complementor. In Cell 3, the non-Chaebol firm engages in direct competition with a Chaebol. In Cell 4, the non-Chaebol firm targets an unserved part of the market with an innovative product or service. The four selected cases such as E.Rae Electronics Industry Company (Co-exister), Intops (Supplier), Pantech (Competitor) and Humax (Niche Player) are analyzed to provide each strategy with richer insights. Following propositions are generated based upon our conceptual framework: Proposition 1: Non-Chaebol firms that have a cooperative relationship with a Chaebol will perform better than firms that do not. Proposition 1a; Co-existers will perform better than Competitors. Proposition 1b: Partners (suppliers or complementors) will perform better than Niche players. Proposition 2: Firms that have no product similarity with a Chaebol will perform better than firms that have product similarity. Proposition 2a: Partners (suppliers or complementors) will perform better than Co.existers. Proposition 2b: Niche players will perform better than Competitors. Proposition 3: Niche players should perform better than Co-existers. Proposition 4: Performance can be rank.ordered in descending order as Partners, Niche Players, Co.existers, Competitors. A team of experts was constituted to categorize each of these 216 non-Chaebol companies into one of the 4 cells in our typology. Simple Analysis of Variance (ANOVA) in SPSS statistical software was used to test our propositions. Overall findings are that it is better to have a cooperative relationship with a Chaebol and to offer products or services differentiated from a Chaebol. It is clear that the only profitable strategy, on average, to compete against the Chaebol is to be a partner (supplier or complementor). Competing head on with a Chaebol company is a costly strategy not likely to pay off for a non-Chaebol firm. Strategies to avoid head on competition with the Chaebol by serving niche markets with differentiated products or by serving the low-end of the market ignored by the Chaebol are better survival strategies. This paper illustrates that there are ways in which small and medium Korean non-Chaebol firms can thrive in a Chaebol environment, though not without risks. Using different combinations of competition and cooperation firms may choose particular positions along the product similarity and cooperative relationship dimensions to develop their competitive strategies-co-exister, competitor, partner, niche player. Based on our exploratory case-study analysis, partner seems to be the best strategy for non-Chaebol firms while competitor appears to be the most risky one. Niche players and co-existers have intermediate performance, though the former do better than the latter. It is often the case with managers of small and medium size companies that they tend to view market leaders, typically the Chaebol, with rather simplistic assumptions of either competition or collaboration. Consequently, many non-Chaebol firms turn out to be either passive collaborators or overwhelmed competitors of the Chaebol. In fact, competition and collaboration are not mutually exclusive, and can be pursued at the same time. As suggested in this paper, non-Chaebol firms can actively choose to compete and collaborate, depending on their environment, internal resources and capabilities.

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Effect of Different Wind-break Net on Reducing Damage of Cold Sea Wind (수도 풍해경감을 위한 방풍강 강목의 효과)

  • 이승필;김상경;이광석;최대웅;김칠용
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.35 no.4
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    • pp.352-361
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    • 1990
  • The reducing effect of wind injury was investigated using several wind-break nets in Youngdeok province where cold-wind damage is often occurred during rice growing season. The white-head damage of rice have been often occurred by typhoon during the period between August 15 to September 10 in the cold wind area of the eastern coastal during the last 11 years (1979-1989). This may suggest that the critical period for heading will be by August 15 in the regions. High evaporation coefficient, more than 250 due to typhoon passage over the regions resulted high injury of white head. Generally, the wind injury have been caused by warm and dry westerlies through Fohn apperance in Taebaeg mountains and by cool-humid wind which blows from coast to inland. The frequency of occurrence of the two types of typhoons were 25, 20%, respectively during rice cultivation. The instalation of wind-break net significantly reduced the wind blowing speed, depending on the net mesher with the higher effect in dence net. The distances between the net and cropping area also affect the wind speed: 23% reduction at 1m distance. 34% at 10m and 28% at 20m, respectively. The reducing effect was also observed even at 10 times height of the wind-break net. The instalation of wind-break net gave several effects on climate factor, showing that temperature increased by 0.8$^{\circ}C$(maximum), 0.7$^{\circ}C$(minimum), 0.6$^{\circ}C$(average) : water temperatures increased by 0.5$^{\circ}C$(maximum), 0.6$^{\circ}C$(minimum), 0.5$^{\circ}C$(average) : soil temperature increased 0.4$^{\circ}C$. The earlier heading and increasing growth rate, use of light, culm length, panicle number per hill, spikelet number per panicle, fertility and 1,000 grain weight were observed in the fields with the wind-break nets resulting in 10-15% increase in rice yield using 0.5${\times}$0.5cm nets. The increasing seedlings per hill gave higher grain yield by 13% in the cold wind damage regions of eastern coastals. and the wind-break was more significant in the field without the wind-break net. Wind injury of rice plant in the cold wind regions of eastern coastals in korea could be reduced by selection of tolerant varieties to wind injury, adjustment of transplanting time, and establishment of wind-break nets.

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Factors Related to Poor School Performance of Elementary School Children (국민학교아동의 학습부진에 관련된 요인)

  • Park, Jung-Han;Kim, Gui-Yeon;Her, Kyu-Sook;Lee, Ju-Young;Kim, Doo-Hie
    • Journal of Preventive Medicine and Public Health
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    • v.26 no.4 s.44
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    • pp.628-649
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    • 1993
  • This study was conducted to investigate the factors related to the poor school performance of the elementary school children. Two schools in Taegu, one in the affluent area and the other in the poor area, were selected and a total of 175 children whose school performance was within low 10 percentile (poor performers) and 97 children whose school performance were within high 5 percentile (good performers) in each class of 2nd, 4th and 6th grades were tested for the physical health, behavioral problem and family background. Each child had gone through a battery of tests including visual and hearing acuity, anthropometry (body weight, height, head circumference), intelligence (Kodae Stanford-Binet test), test anxiety (TAI-K), neurologic examination by a developmental pediatrician and heavy metal content (Pb, Cd, Zn) in hair by atomic absorption spectrophotometry. A questionnaire was administered to the mothers for prenatal and prenatal courses of the child, family environment, child's developmental history, and child's behavioral and learning problems. Another questionnaire was administered to the teachers of the children for the child's family background, arithmatic & language abilities and behavioral problem. The poor school performance had a significant correlation with male gender, high birth order, broken home, low educational and occupational levels of parents, visual problem, high test anxiety score, attention deficit hyperactivity disorder (ADHD), poor physical growth (weight, height, head circumference) and low I.Q. score. The factors that had a significant correlation with the poor school performance in multiple logistic regression analysis were child's birth order (odds ratio=2.06), male gender(odds ratio=5.91), broken home(odds ratio=9.29), test anxiety score(odds ratio=1.07), ADHD (odds ratio=9.67), I.Q. score (odds ratio=0.85) and height less than Korean standard mean-1S.D.(odds ratio=11.12). The heavy metal contents in hair did not show any significant correlation with poor school performance. However the lead and cadmium contents were high in males than in females. The lead content was negatively correlated with child's grade(P<0.05) and zinc was positively correlated with grade (P<0.05). among the factors that showed a significant correlation with the poor school performance, high birth order, short stature and ADHD may be modified by a good family planning, good feeding practice for infant and child, and early detection and treatment of ADHD. Also, teacher and parents should restrain themselves from inducing excessive test anxiety by forcing the child to study and over-expecting beyond the child's intellectual capability.

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Ototoxic Evaluation of Cis-platinum (Cis-Platinum의 이중독증에 관한 임상적 고찰)

  • 홍원표;정명현;오혜경;이경재
    • Proceedings of the KOR-BRONCHOESO Conference
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    • 1982.05a
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    • pp.17.1-17
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    • 1982
  • In 1965, Rosenberg reported that platinum compounds not only inhibit growth and cell division of E. coli but also has anti-tumor activity. Since then, through animal and clinical experiments by Welsch(1971), Speer(1972), Rossof(1972), Hill(1974), and Wittes(1975), it was proved that Cis-platinum has excellent supressive effects on malignant tumor, especially on head and neck cancer. Accordingly, Cis-platinum is now widely used, sometimes without any other durg, or sometimes with Bleomycin and Methotrexate etc. Inspite of the strong anticancer effect, the use of Cis-platinum is quite often discouraged because of the reports that Cis-platinum causes auditory impairment at high frequencies above the speech range due to inner ear damage and irreversible change in the renal tubules. Since Kohonen et al(1965), Standnicki et al(1974) reported that Cisplatinum has toxic effects at the basal turn of the cochlea using guinea pig, many studies on ototoxicity after infusion of Cis-platinum have been carried out using animals. But the studies on ototoxicity in human beings can hardly be found except in reports by Piel et al(1974) and Hong et al (1979). So the authors did a study which tried to clarify the ototoxic effect by comparing the hearing level after infusion of Cis-plastinum with the hearing level before infusion of Cis-plastinum in 30 patients who was treated with Cis-platinum and admitted to the dept. of otolaryngology of Yonsei University Hospital during 2 years and a half from July. 1979 to March. 1982 and the following results were obtained. 1) The results of auditory evaluation, using the pure tone average, hearing loss of 4kHz and 8kHz, Speech Reception Threshold, PB score, SISI showed that the difference of dosage does not change the hearing level after infusion of Cis-platinum and before infusion of Cis-platinum. 2) Cis-platinum had no effect on the hearing level of patients with conductive hearing loss, or with sensorineural hearing loss, as well as with normal hearing level. 3) The infusion of Cis-platinum did not cause any change in creatinine clearance, creatinine, uric acid, but only one case showed that Cis-platinum caused severe nephrotoxicity. 4) The infusion of Cis-plastinum did not cause any change in hemoglobin, leukocyte count, platelet count and there was no correlation with the amount of infusion. 5) To see the side effect of hydration practiced with the infusion of Cis-platinum, the electrolytes, particularly the K level in the serum was measured. But the results did not show any change. 6) Judging from the results of this study mentioned above, ototoxicity caused by infusion of Cis-platinum can be prevented by sufficient hydration. Also the results might say that the appropriate method of infusion of Cis-platinum might be effective in the patients with head and neck cancer who had sensorineural hearing loss for whom the infusion of Cis-platinum has been absolutely cotraindicated.

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Study on body measurement of fetuses and neonates in Korean native goats (한국재래산양(韓國在來山羊)의 태아(胎兒) 및 신생자(新生仔)의 체적측정치(體尺測定値)에 관(關)한 연구(硏究))

  • Kim, Chong-sup;Choe, Sang-yong;Chung, Hyon-sik;Kim, Taeg-seog
    • Korean Journal of Veterinary Research
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    • v.28 no.2
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    • pp.213-219
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    • 1988
  • The measurement was investigated with 18 heads of fetus(60, 90, 120 days of gestation) and neonate in Korean native goats. The results were summerized as follows: 1. The crown-rump length of fetuses at 60, 90, 120 days of gestation and neonate was 8.71, 20.83, 31.10 and 34.93 cm, respectively. 2. The length of small intestine at 60, 90, 120 days of gestation and neonate was 32.28, 157.10, 303.52 and 457.06 cm, respectively. 3. The length of large intestine at 60, 90, 120 days of gestation and neonate was 9.20, 37.70, 82.06 and 94.46 cm, respectively. 4. The ratio of intestinal length to crown-rump length at 60, 90, 120 days of gestation and neonate was 4.76, 9.45, 12.40 and 15.79 times, respectively. 5. At 60 days of gestation, the total length of the vertebral column was $7.40{\pm}0.72cm$, The mean length of each segment of the vertebral column was $1.55{\pm}0.20cm$ in cervical, $2.29{\pm}0.21cm$ in thoracic, $1.46{\pm}0.10cm$ in lumbar, $0.51{\pm}0.04cm$ in sacral and $1.59{\pm}0.17cm$ in coccygeal vertebrae. 6. At 90 days of gestation, the total length of the vertebral column was $16.52{\pm}0.80cm$. The mean length of each segment of the vertebral column was $3.72{\pm}0.12cm$ in cervical, $5.09{\pm}0.26cm$ in thoracic, $3.22{\pm}0.04cm$ in lumbar, $1.97{\pm}0.03cm$ in sacral and $2.64{\pm}0.35cm$ in coccygeal vertebrae. 7. At 120 days of gestation, the total length of the vertebral column was $26.35{\pm}0.34cm$. The mean length of each segment of the vertebral column was $6.09{\pm}0.16cm$ in cervical, $7.81{\pm}0.07cm$ in thoracic, $5.08{\pm}0.07cm$ in lumbar, $3.07{\pm}0.02cm$ in and $4.31{\pm}0.02cm$ in coccygeal vertebrae. 8. In the neonate, the total length of the vertebral column was $32.41{\pm}1.57cm$. The mean length of each segment of vertebral was $7.70{\pm}0.25cm$ in cervical, $9.97{\pm}0.68cm$ in thoracic, $5.58{\pm}0.44cm$ in lumbar, $3.85{\pm}0.15cm$ in sacral and $5.05{\pm}0.06cm$ coccygeal vertebrae. 9. The chest girth at 60, 90, 120 days of gestation and neonate was $6.13{\pm}0.51$, $13.45{\pm}0.84$, $20.28{\pm}1.53$ and $22.94{\pm}1.75cm$, respectively. 10. The head length at 60, 90, 120 days of gestation and neonate was $2.93{\pm}0.07$, $6.67{\pm}0.13$, $8.84{\pm}0.51$ and $9.76{\pm}0.44cm$, respectively. 11. The width of the head at 60, 90, 120 days of gestation and neonate was $2.20{\pm}0.13$, $4.45{\pm}0.11$, $5.33{\pm}0.20$ and $5.51{\pm}0.32cm$, respectively.

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Reproductive Cycle of Small Filefish, Rudarius ercodes (그물코쥐치, Rudarius ercodes의 생식주기)

  • LEE Taek Yuil;HANYU Isao
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.17 no.5
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    • pp.423-435
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    • 1984
  • The reproductive cycle of the small filefish, Rudarius ercodes was investigated based on the annual variations of gonadosomatic index(GSI) and hepatosomatic index(HSI) by electronic and photic microscophy. The specimens used were collected at the coastal area of Benden island, Sizuokagen, Japan, from September 1982 to August 1983. GSI began to increase from March, starting season of longer daylength and higher water temperature, and reached the maximum value between June and August. It began to decrease from September with the lowest value appearing between November and February without any evident variation. The annual variations of HSI were not distinct in male filefish and were negatively related to GSI in female : HSI decreased in the summer season when the ovary was getting mature and reached the maximum in the winter season when the ovary was getting retrogressive. The ovary consisted of a pair of saccular structure with numerous ovarian sacs branched toward the median cavity. Oogonia divided and proliferated along the germinal epithelium of the ovarian sac. Young oocytes with basophile cytoplasm showed several scattering nucleoli along the nuclear membrane. when the oocytes growing to about 300 ${\mu}m$, nuclear membrane to disappear with nucleus migrating toward the animal pole. The regions of protoplasm were extremely confined within the animal hemisphere in which most of cytoplasms were filled with yolk materials and oil drops. After ovulation, residual follicles and growing oocytes remaining in the ovarian sacs degenerated. But perinucleatic young oocytes without follicles formed were not degenerated, and growing continuously still in the next year. Mitochondria and endoplasmic reticula in the cytoplasm remarkably increased with oocytes maturing and yolk accumulating. Those were considered to be functionally related to the yolk accumulation. Five or six layers of possible vitellogenin, oval-shaped disc structures with high electron density, appeared in the apex of follicular processes stretching to the microvilli pits of mature oocytes. Testis consisting of a pair of lobular structures in the right and left were united in the posterior seminal vesicle, Cortex of testis was composed of several seminiferous tubules, and medulla consisting of many sperm ducts connected with tubules. Steroid hormone-secreting cells with numerous endoplasmic reticula and large mitochondria of well developed cristae were recognized in the interstitial cells of the growing testis. Axial filament of spermatozoon invaginated deeply in the central cavity of the nucleus and the head formed U-shape with acrosome severely lacking, mitochondria formed large globular paranuclei at the posterior head, and microtubular axoneme of the tail represented 9+9+2 type. The annual reproductive cycles could be divided into five successive stages : growth(March to July), maturation(May to September), Spawning(mid May to early October) and resting stages(October to February). The spawning peak occurred from June to August.

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A New High Qualilty Rice Variety with High Head Rice Ratio and Milling Recovery, "Chilbo" (완전미율, 도정수율 높은 중만생 고품질 벼 신품종 "칠보(七寶)")

  • Kim, Jeong-Il;Chang, Jae-Ki;Park, No-Bong;Yeo, Un-Sang;Oh, Byeong-Geun;Kang, Jung-Hun;Kwon, Oh-Deog;Shin, Mun-Sik;Park, Dong-Soo;Kwak, Do-Yeon;Lee, Jong-Hee;Song, You-Cheon;Kim, Chun-Song;Cho, Jun-Hyun;Yi, Gihwan;Lee, Ji-Yoon;Nam, Min-Hee;Kim, Sang-Yeol;Ahn, Jong-Woong;Ku, Yeon-chung;Kim, Jae-Kyu
    • Korean Journal of Breeding Science
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    • v.41 no.4
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    • pp.547-551
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    • 2009
  • A new commercial rice variety "Chilbo" is a japonica rice (Oryza sativa L.) with resistance to rice stripe virus and high grain quality. It was developed by the rice breeding team of Yeongdeog Substation, NICS, RDA in 2007. This variety was derived from a cross between "Yeongdeog 26" with wind tolerance and lodging resistance and "Koshihikari" with good grain quality. A promising line, YR21324-119-3-2 was selected by a pedigree breeding method and designated as "Yeongdeog 44" in 2004. Regional adaptation yield trials were carried out at eleven locations from 2005 to 2007. As a result, "Yeongdeog 44" was released as a high yielding rice variety with high grain qualilty and virus resistance with the name of "Chilbo". It is short 76cm in culm length and has medium-late growth duration. This variety is resistant to stripe virus and middle resistant to leaf blast disease. It is also tolerant to cold, dried wind. Milled rice kernel of "Chilbo" is translucent, clear in chalkiness. Panel test proved that and it has good eating quality. Head rice ratio of Chilbo is high compared to the check variety, Hwaseongbyeo. Yield potential of "Chilbo" in milled rice is about 5.57MT/ha at ordinary fertilizer level of local adaptability test. This variety would be adaptable to Yeongnam plain, south & east-south coastal, south mid-mountainous, middle plain area of Korean peninsula.

Egg Development and Morphology of Larva and Juvenile of Liparis tanakae in the Coastal Waters off Yeosu (여수 연안산 꼼치(Liparis tanakae)의 난발생 및 자치어 형태발달)

  • Kyung-Ae Jung;Na-Young Jeon;Sang-Hun Cha;Sung-Hoon Lee;Tae-Sik Yu;Keong-Ho Han
    • Korean Journal of Ichthyology
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    • v.35 no.4
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    • pp.263-269
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    • 2023
  • This study aims to contribute to the research on resource recovery for the rapidly declining population of Liparis tanakae by observing the larval development process and the morphology of juveniles based on their growth. Natural spawning eggs collected in Yeosu were used for observing the process of egg development and larval morphology. The water temperature during the rearing process was maintained at 12.3~13.5℃ (average 12.7℃). The fertilized eggs had an egg diameter ranging from 1.57 to 1.79 mm (average 1.71 mm) and were spherical and adhesive. Within 4 hours 35 minutes after fertilization, they reached the two-cell stage, and after 74 hours 10 minutes, the formation of the yolk sac began. At 106 hours post-fertilization, a caudal fin appeared at the tail tip. Hatching began at 526 hours, and the larvae developed with the yolk sac positioned just behind the eyes. The newly hatched larvae had both the mouth and anus open. Melanophores appeared inside the lower jaw and around the tail on the third day after hatching. By the 16th day after hatching, most of the yolk was absorbed, and melanophores were visible in the head region. Finally, on the 63rd day after hatching, the head region significantly developed, and the body shape and mouth were similar to those of an adult fish, signifying the transition to the juvenile stage. This study will serve as valuable data for aquaculture techniques related to the conservation and restoration of fish species based on the hatching and juvenile morphology of Liparis tanakae.

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.

The Effect of Recombinant Human Epidermal Growth Factor on Cisplatin and Radiotherapy Induced Oral Mucositis in Mice (마우스에서 Cisplatin과 방사선조사로 유발된 구내염에 대한 재조합 표피성장인자의 효과)

  • Na, Jae-Boem;Kim, Hye-Jung;Chai, Gyu-Young;Lee, Sang-Wook;Lee, Kang-Kyoo;Chang, Ki-Churl;Choi, Byung-Ock;Jang, Hong-Seok;Jeong, Bea-Keon;Kang, Ki-Mun
    • Radiation Oncology Journal
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    • v.25 no.4
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    • pp.242-248
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    • 2007
  • Purpose: To study the effect of recombinant human epidermal growth factor (rhEGF) on oral mucositis induced by cisplatin and radiotherapy in a mouse model. Materials and Methods: Twenty-four ICR mice were divided into three groups-the normal control group, the no rhEGF group (treatment with cisplatin and radiation) and the rhEGF group (treatment with cisplatin, radiation and rhEGF). A model of mucositis induced by cisplatin and radiotherapy was established by injecting mice with cisplatin (10 mg/kg) on day 1 and with radiation exposure (5 Gy/day) to the head and neck on days $1{\sim}5$. rhEGF was administered subcutaneously on days -1 to 0 (1 mg/kg/day) and on days 3 to 5 (1 mg/kg/day). Evaluation included body weight, oral intake, and histology. Results: For the comparison of the change of body weight between the rhEGF group and the no rhEGF group, a statistically significant difference was observed in the rhEGF group for the 5 days after day 3 of. the experiment. The rhEGF group and no rhEGF group had reduced food intake until day 5 of the experiment, and then the mice demonstrated increased food intake after day 13 of the of experiment. When the histological examination was conducted on day 7 after treatment with cisplatin and radiation, the rhEGF group showed a focal cellular reaction in the epidermal layer of the mucosa, while the no rhEGF group did not show inflammation of the oral mucosa. Conclusion: These findings suggest that rhEGF has a potential to reduce the oral mucositis burden in mice after treatment with cisplatin and radiation. The optimal dose, number and timing of the administration of rhEGF require further investigation.