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Antitumor and Antimetastatic Effects of Toxoplasma Gondii in Mice with Lewis Lung Carcinoma (Lewis 폐암 마우스 모델에서 톡소포자충에 의한 항암 및 항전이 효과)

  • Kim, Ju-Ock;Jung, Sung-Soo;Park, Hee-Sun;Kim, Myoung-Hoon;Kim, Sun-Young;Lee, Young-Ha
    • Tuberculosis and Respiratory Diseases
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    • v.52 no.4
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    • pp.317-329
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    • 2002
  • Background : Immunotherapy is another treatment modality for various cancers. There is little information on the antitumor effects of immunotherapy on implanted lung cancer mouse models. Toxoplasma gondii is able to potently induce a nonspecific stimulation of the host immune system. Therefore, this study evaluated the antitumor and antimetastatic effect of nonspecific immune stimulation by T. gondii in a Lewis lung cancer mouse model. Methods : Female C57BL/6 mice were injected with either Lewis lung cancer cells ($1{\times}10^6$ per mouse) or 5 cysts from the T. gondii Me49 strain with various schedules. The number of survival days, the tumor size of the implanted muscle and the histopathological findings of each group were noted. In addition to these mice, the Toxoplasma antigen($50{\mu}g$ per mouse) or a lymphokine (0.5 ml per mouse) was added to boost the immunotherapy. Results : No mouse in the Toxoplasma-infected group had died, whereas the mice receiving only the cancer cells (cancer control) survived for $29.1{\pm}4.4$ days. Cancer cells were revealed from 1 week after cancer cell inceulation in the muscle and from 3 weeks in the lung of the cancer control, whereas cancer cells were found in both the preinfection control and coinfection control groups from 2 weeks and 4 weeks in the lung respectively. The in the number of survival days were $32.4{\pm}3.3$ in the mice receiving T. gondii 2 weeks prior to the cancer cells inoculation (preinfection control), $30.9{\pm}5.1$ in mice received both simultaneously (coinfection control), and $34.9{\pm}2.9$ in mice received T. gondii 2 weeks after cancer cells implantation (postinfection control). These 3 infection groups had significantly longer survival days and suppressed tumor growth than those of the cancer control. In addition to these mice, and injection with the Toxoplasma antigen alone or in combination with lymphokine resulted in a significant increase in the number of survival days. Conclusion : These findings suggest that an injection with T. gondii can induce the antitumor and antimetastatic effects in Lewis lung cancer mouse models. Moreover, these effects were increased with an injection of the Toxoplasma antigen alone or in combination with lymphokine. However, this therapy can not prevent the development of cancer.

The Relationship between Expression of EGFR, MMP-9, and C-erbB-2 and Survival Time in Resected Non-Small Cell Lung Cancer (수술을 시행한 비소세포 폐암 환자에서 EGFR, MMP-9 및 C-erbB-2의 발현과 환자 생존율과의 관계)

  • Lee, Seung Heon;Jung, Jin Yong;Lee, Kyoung Ju;Lee, Seung Hyeun;Kim, Se Joong;Ha, Eun Sil;Kim, Jeong-Ha;Lee, Eun Joo;Hur, Gyu Young;Jung, Ki Hwan;Jung, Hye Cheol;Lee, Sung Yong;Lee, Sang Yeub;Kim, Je Hyeong;Shin, Chol;Shim, Jae Jeong;In, Kwang Ho;Kang, Kyung Ho;Yoo, Se Hwa;Kim, Chul Hwan
    • Tuberculosis and Respiratory Diseases
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    • v.59 no.3
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    • pp.286-297
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    • 2005
  • Background : Non-small cell lung cancer (NSCLC) is a common cause of cancer-related death in North America and Korea, with an overall 5-year survival rate of between 4 and 14%. The TNM staging system is the best prognostic index for operable NSCLC . However, epidermal growth factor receptor (EGFR), matrix metalloproteinase-9(MMP-9), and C-erbB-2 have all been implicated in the pathogenesis of NSCLC and might provide prognostic information. Methods : Immunohistochemical staining of 81 specimens from a resected primary non-small cell lung cancer was evaluated in order to determine the role of the biological markers on NSCLC . Immunohistochemical staining for EGFR, MMP-9, and C-erbB-2 was performed on paraffin-embedded tissue sections to observe the expression pattern according to the pathologic type and surgical staging. The correlations between the expression of each biological marker and the survival time was determined. Results : When positive immunohistochemical staining was defined as the extent area>20%(more than Grade 2), the positive rates for EGFR, MMP-9, and C-erbB-2 staining were 71.6%, 44.3%, and 24.1% of the 81 patients, respectively. The positive rates of EGFR and MMP-9 stain for NSCLC according to the surgical stages I, II, and IIIa were 75.0% and 41.7%, 66.7% and 47.6%, and 76.9% and 46.2%, respectively. The median survival time of the EGFR(-) group, 71.8 months, was significantly longer than that of the EGFR(+) group, 33.5 months.(p=0.018, Kaplan-Meier Method, log-rank test).. The MMP-9(+) group had a shorter median survival time than the MMP-9(-) group, 35.0 and 65.3 months, respectively (p=0.2). The co-expression of EGFR and MMP-9 was associated with a worse prognosis with a median survival time of 26.9 months, when compared with the 77 months for both negative-expression groups (p=0.0023). There were no significant differences between the C-erbB-2(+) and C-erbB-2 (-) groups. Conclusion : In NSCLC, the expression of EGFR might be a prognostic factor, and the co-expression of EGFR and MMP-9 was found to be associated with a poor prognosis. However, C-erbB-2 expression had no prognostic significance.

Evaluation of the Fruit Quality Indices during Maturation and Ripening and the Influence of Short-term Temperature Management on Shelf-life during Simulated Exportation in 'Changjo' Pears (Pyrus pyrifolia Nakai) (배 신품종 '창조'의 성숙 중 품질 요인 변화 및 수송온도 환경에 따른 반응성)

  • Lee, Ug-Yong;Choi, Jin-Ho;Ahn, Young-Jik;Chun, Jong-Pil
    • Journal of Bio-Environment Control
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    • v.26 no.4
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    • pp.378-385
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    • 2017
  • In this study, we evaluated the changes of fruit quality indices during fruit development and ripening in Korean new pear cultivar 'Changjo', developed from a cross between 'Tama' and '81-1-27' ('Danbae' ${\times}$ 'Okusankichi') in 1995 and named in 2009, to determine appropriate harvest time and to enhance the market quality and broaden the cultivation area. The fruits of 'Changjo' pears harvested from 132 days after full bloom (DAFB) to 160 DAFB. Fruit growth and quality indices were monitored at 1 week interval by measuring fruit weight, length, diameter, firmness, and taste related quality indices. The calculated fruit fresh weight increased continuously with fruit development and reached to an average of 594g on Sep. 20 (160 DAFB). The ratio of length to diameter declines as fruit maturation progress, resulting in 0.898 for ripe fruit stage as a round oblate shape. Flesh firmness of 'Changjo' pears showed over 30N until 153 DAFB and then decreased abruptly with fruit ripening, reaching a final level of about 26.44N on 160 DAFB. Starch content of fruit sap was also decreased abruptly after 146 DAFB which decreased almost half of the fruits harvested at 139 DAFB. In parallel with the decrease of flesh firmness, ethanol insoluble solids (EIS) content decreased sharply with fruit ripens, only 50% of EIS was detected on the fruits harvested on 160 DAFB when compared to that of the fruits harvested on 139 DAFB (Aug. 30). The maximum value of soluble solids contents was observed in the fruits harvested on 153 DAFB, resulting in $14.2^{\circ}Brix$. The changes of skin color difference $a^*$ which means loss of green color occurred only after 139 DAFB, coincide with the decrease of SPAD value of the fruit skin. The sugars of the 80% ethanol soluble fraction consisted mainly of fructose, sorbitol, glucose and sucrose, also increased during maturation and ripening. Fructose and sucrose contents were larger than those of glucose and sorbitol in flesh tissues. These results were explained that stored starch is converted to soluble sugars during fruit maturation, mainly in fructose and sucrose increasing the sweetness of this cultivar. Total polyphenols were increased up to middle of fruit maturation (146 DAFB) and then decreased continuously until the end of fruit maturation. Consequently, our results suggested that the commercial harvest time of 'Changjo' pears should not be passed 153 DAFB and late harvest of this cultivar would not good for quality maintenance during shelf-life. As a result of the post-harvest low-temperature acclimation experiment during the short-term transportation period, fruits harvested at 146 DAFB tended to maintain higher firmness after 14 days of simulated marketing at $25^{\circ}C$ compared to fruits harvested at 153 DAFB regardless of temperature set. And, the slower the rate of decrease to the final transport temperature of $5^{\circ}C$, the higher the incidence of internal browning and ethylene production. Therefore, in order to suppress the physiological disorder and to maintain the fruit quality when exporting to Southeast Asia in the 'Chanjo' pears, it is desirable to lower the temperature of the fruits within a short time after harvest and to set the harvest time before 146 days after full bloom.

Studies on Microbial and Enzymatic Actions during the Ripening Process of Salted Alaska Pollack Tripe (창난 젓갈의 숙성 과정 중 미생물 및 자기소화효소 작용에 관한 연구)

  • Chae, Soo-Kyu
    • The Korean Journal of Food And Nutrition
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    • v.24 no.3
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    • pp.340-349
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    • 2011
  • This study examined the roles of autolytic enzymes and microorganisms in the ripening process of salted Alaska pollack tripe made with various concentrations of salt i.e, 7.5% and 20% by weight. Salted Alaska pollack tripe treated with antibiotic agents for the inhibition of microbial growth and a control were prepared experimentally, and changes in chemical composition and viable cell counts were investigated, individually, during the ripening process. Just after the preparation of the low salt Alaska pollack tripe made with 7.5% salt, viable bacterial cells occurred at a level of $10^5$ CFU/g. In the control, bacterial counts increased rapidly to $10^7$ CFU/g by the 14th day of ripening. However, in the sample treated with antibiotic agents, counts were decreased to a level of $10^4$ CFU/g by the 3rd day of ripening and increased gradually to $10^6$ CFU/g by the 5th day of ripening, and then the same value was maintained there-after. Just after the preparation of the high salt Alaska pollack tripe made with 20% salt, viable bacterial cells occurred at a level of $10^3$ CFU/g. In both the samples treated with antibiotic agents and the control, bacterial counts decreased rapidly to $10^0$ CFU/g by the 45th day of ripening and increased gradually there-after. The content of amino type nitrogen was 76.3 mg% just after the preparation of the low salt Alaska pollack tripe made with 7.5% salt. Amino type nitrogen content was increased to 283.5 mg% by the 5th day of proper ripening in the control, but it was increased to 208.0 mg% in the sample treated with antibiotic agents. The difference in amino type nitrogen content was 75.5 mg/100 g. The content of amino type nitrogen was 57.2 mg% just after the preparation of the high salt Alaska pollack tripe made with 20% salt. Amino type nitrogen content was increased to 198.3 mg by the 60th day of proper ripening in the control, but it was increased to 162.0 mg% in the sample treated with the antibiotic agents. The difference in amino type nitrogen content was 36.3 mg/100 g. The contents of VBN and TMA-N were 102.1 mg% and 20.5 mg%, respectively, at the 7th day of ripening in the low salt Alaska pollack tripe made with 7.5% salt. The content of VBN was 60.0 mg% and TMA-N was not detected at the 21st day of ripening in the sample treated with antibiotic agents. The control sample was spoiled by the 7th day of ripening but the sample treated with antibiotic agents was not spoiled by the 21st day of ripening. On the other hand, VBN content was 37.2 mg% and TMA-N was not detected at the 90th day of ripening in the high salt Alaska pollack tripe made with 20% salt, and the control sample was not spoiled.

Clinical Efficacy of Clomiphene Citrate and Letrozole Combined with Gonadotropins for Superovulation in Patients with Clomiphene-Induced Thin Endometrium (클로미펜에 얇은 자궁내막을 보이는 환자에서 성선자극호르몬 병합 과배란유도시 클로미펜과 레트로졸의 임상적 효용성)

  • Lee, Eun-Joo;Park, Hyun-Jong;Yang, Hyo-In;Lee, Kyung-Eun;Seo, Seok-Kyo;Kim, Hye-Yeon;Cho, Si-Hyun;Choi, Young-Sik;Lee, Byung-Seok;Park, Ki-Hyun;Cho, Dong-Jae
    • Clinical and Experimental Reproductive Medicine
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    • v.36 no.2
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    • pp.111-119
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    • 2009
  • Objective: The aim of this study was to compare the clinical efficacy of clomiphene citrate (CC) and letrozole combined with gonadotropins for controlled ovarian stimulation (COS) in patients with CC-induced thin endometrium Methods: Fifty-one intrauterine insemination cycles performed in patients who previously had a thin endometrium (<8 mm) to ovulation induction using CC were included in this study. A CC 100 mg/day (CC+gonadotropin group, n=26) or letrozole 2.5 or 5 mg/day (letrozole+gonadotropin group, n=25) was administered on day 3~7 of the menstrual cycle, combined with gonadotropins at dose 75~150 IU every other day starting on day 5~7. We compared total dose of gonadotropin used, endometrial thickness, endometrial pattern, number of follicles ${\geq}14\;mm$ on hCG day, pregnancy rate and multiple pregnancy rate between the two groups, which were statistically analyzed using Mann-Whitney U test or Fisher's exact test, where appropriate. Results: There were no significant differences in clinical characteristics such as age, duration of infertility, number of previous IUI cycles, basal serum hormone levels and cause of infertility between the two groups. In both groups, the endometrium was significantly thicker than that of previous ovulation induction cycles using CC. No significant differences were found in the total dose of gonadotropin used, day of hCG administration, the rate of triple endometrium and pregnancy rate. The number of follicles ${\geq}14\;mm$ was significantly lower ($3.7{\pm}1.7$ vs. $2.8{\pm}1.7$, p=0.03) and the endometrium on hCG day was significantly thicker ($7.7{\pm}1.5$ vs. $9.1{\pm}1.7$, p=0.001) in letrozole+gonadotropin group compared to CC+gonadotropin group. Conclusion: The clomiphene citrate and letrozole combined with gonadotropins appear to avoid the undesirable effects on the endometrium frequently seen with CC for ovulation induction. However, in terms of adequate endometrial development or optimal follicular growth, letrozole may be more beneficial than CC for gonadotropin-combined COS in patients with CC-induced thin endometrium. Further prospective randomized controlled studies in a larger scale will be necessary to confirm our findings.

A Study on the Curriculum for Record Management Science Education - with focus on the Faculty of Cultural Information Resources, Surugadai University; Evolving Program, New Connections (기록관리학의 발전을 위한 교육과정연구 -준하태(駿河台)(스루가다이)대학(大學)의 경우를 중심(中心)으로-)

  • Kim, Yong-Won
    • Journal of Korean Society of Archives and Records Management
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    • v.1 no.1
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    • pp.69-94
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    • 2001
  • The purpose of this paper is to provide an overview of the current status of the records management science education in Japan, and to examine the implications of the rapid growth of this filed while noting some of its significant issues and problems. The goal of records management science education is to improve the quality of information services and to assure an adequate supply of information professionals. Because records management science programs prepare students for a professional career, their curricula must encompass elements of both education and practical training. This is often expressed as a contrast between theory and practice. The confluence of the social, economic and technological realities of the environment where the learning takes place affects both. This paper reviews the historical background and current trends of records management science education in Japan. It also analyzes the various types of curriculum and the teaching staff of these institutions, with focus on the status of the undergraduate program at Surugadai University, the first comprehensive, university level program in Japan. The Faculty of Cultural Information Resources, Surugadai University, a new school toward an integrated information disciplines, was opened in 1994, to explore the theory and practice of the management diverse cultural information resources. Its purpose was to stimulate and promote research in additional fields of information science by offering professional training in archival science, records management, and museum curatorship, as well as librarianship. In 1999, the school introduced a master program, the first in Japan. The Faculty has two departments and each of them has two courses; Department of Sensory Information Resources Management; -Sound and Audiovisual Information Management, -Landscape and Tourism Information Management, Department of Knowledge Information Resources Management; -Library and Information Management, -Records and Archives Management The structure of the entire curriculum is also organized in stages from the time of entrance through basic instruction and onwards. Orientation subjects which a student takes immediately upon entering university is an introduction to specialized education, in which he learns the basic methods of university education and study, During his first and second years, he arranges Basic and Core courses as essential steps towards specialization at university. For this purpose, the courses offer a wide variety of study topics. The number of courses offered, including these, amounts to approximately 150. While from his third year onwards, he begins specific courses that apply to his major field, and in a gradual accumulation of seminar classes and practical training, puts his knowledge grained to practical use. Courses pertaining to these departments are offered to students beginning their second year. However, there is no impenetrable wall between the two departments, and there are only minor differences with regard requirements for graduation. Students may select third or fourth year seminars regardless of the department to which they belong. To be awarded a B.A. in Cultural Information Resources, the student is required to earn 34 credits in Basic Courses(such as, Social History of Cultural Information, Cultural Anthropology, History of Science, Behavioral Sciences, Communication, etc.), 16 credits in Foreign Languages(including 10 in English), 14 credits on Information Processing(including both theory and practice), and 60 credits in the courses for his or her major. Finally, several of the issues and problems currently facing records management science education in Japan are briefly summarized below; -Integration and Incorporation of related areas and similar programs, -Curriculum Improvement, -Insufficient of Textbooks, -Lack of qualified Teachers, -Problems of the employment of Graduates. As we moved toward more sophisticated, integrated, multimedia information services, information professionals will need to work more closely with colleagues in other specialties. It will become essential to the survival of the information professions for librarians to work with archivists, record managers and museum curators. Managing the changes in our increasingly information-intensive society demands strong coalitions among everyone in cultural Institutions. To provide our future colleagues with these competencies will require building and strengthening partnerships within and across the information professions and across national borders.

Serum 25-Hydroxy Vitamin $D_3$ Analysis of Korean People (한국인 일반인의 혈청 25-Hydroxy Vitamin $D_3$의 분석)

  • Kim, Bo-Kyung;Jung, Hyun-Mi;Kim, Yun-Kyung;Kim, So-Young;Kim, Jee-Hyun
    • The Korean Journal of Nuclear Medicine Technology
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    • v.14 no.1
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    • pp.133-137
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    • 2010
  • Purpose: The main function of vitamin D is the mineralization of the brain by increase of calcium and phosphorus, in case it is insufficient in children, lime deposition on cartilage cannot occur so it leads to rachitis, and in adults, it leads to osteomalacia or osteoporosis. It is also strongly believed in the academic world that vitamin D can restrict the growth of cancer cells and prevent heart diseases, which is also somewhat proven in epidemiological researches. While the right density of vitamin D is still being studied, 20-32 ng/mL is believed to be the most ideal density. Therefore, I wanted analyze how much density of 25-Hydroxyvitamin D3 that Koreans possess. Materials and Methods: From February 20th, 2008 to April 21st, 2009, the collection of 2800 serums, from medical examination treated subjects by Neodin Medical Institute, have been tested. The targets were tested by 25-Hydroxyvitamin D (125I Kit: Diasorin, USA), and were analyzed by dividing into many different categories (gender, age, season, region). Results: The average density of male were 20 ng/mL, female 17.08 ng/mL. Per age groups, the density of males were as follows: 10~20-18 ng/mL, 21~30-17 ng/mL, 31~40-19 ng/mL, 41~50-21 ng/mL, 51~60-22 ng/mL, 61~70-22 ng/mL, 71~80-22 ng/mL and 81~90-19.9 ng/mL. Average density of females per age groups, were as follows: 10~20-16 ng/mL, 20~30-15.26 ng/mL, 30~40-16 ng/mL, 40~50-17 ng/mL, 50~60-19 ng/mL, 60~70-19 ng/mL, 70~80-19 ng/mL, and 80~90-17 ng/mL. Per seasons, From December to May, the subjects showed the density of 15.97 ng/mL, while from June to November, it showed 21.60 ng/mL. On density of males from January to April regionally, Seoul+Gyeonggi-Do-15.52 ng/mL, Gangwon-Do-15.33 ng/mL, Choongchung-Do-18.03 ng/mL, Jeonla-Do-18.68 ng/mL, Gyungsang-Do-18.76 ng/mL and Cheju Do-21.23 ng/mL. Conclusions: The vitamin D of Koreans is has been insufficient compared to the suggested amount. Ultraviolet rays, which is the main source of vitamin D is critical, therefore it is suggested that more outdoor activities can definitely help.

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Pro-inflammatory Cytokine Expression Through NF-${\kappa}B/I{\kappa}B$ Pathway in Lung Epithelial Cells (폐 상피세포에서 NF-${\kappa}B/I{\kappa}B$ 경로에 의한 염증매개 사이토카인의 발현)

  • Park, Gye-Young;Lee, Seung-Hee;HwangBo, Bin;Yim, Jae-Joon;Lee, Choon-Taek;Kim, Young-Whan;Han, Sung-Koo;Shim, Young-Soo;Yoo, Chul-Gyu
    • Tuberculosis and Respiratory Diseases
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    • v.49 no.3
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    • pp.332-342
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    • 2000
  • Background : The importance of pro-inflammatory cytokines, especially tumor necrosis factor $\alpha$ (INF-$\alpha$) and interleukin-1$\beta$ (IL-1$\beta$), have been extensively documented in the generation of inflammatory lung disease. Lung epithelial cells are also actively involved in initiating and maintaining inflammation by producing pro-inflammatory mediators. Understanding the mechanism of pro-inflammatory cytokine expression in lung epithelial cells is crucial to the development of new therapeutic modalities for inflammatory lung disease. Transcription of most pro-inflammatory cytokines is dependent on the activation of NF-${\kappa}B$. However, the relationship between pro-inflammatory cytokine expression and NF-${\kappa}B/I{\kappa}B$ pathway in lung epithelial cells is not clear. Methods : BEAS-2B, A549, Na-H157, NCI-H719 cells were stimulated with IL-$1{\beta}$ or TNF-$\alpha$ at various times, and then IL-8 and TNF-$\alpha$mRNA expressions were assayed by Northern blot analysis. IL-$1{\beta}$ or TNF-$\alpha$-induced NF-${\kappa}B$ activation was assessed by the nuclear translocation of p65 NF-${\kappa}B$ subunit. The degradation of $I{\kappa}B{\alpha}$ and $I{\kappa}B{\beta}$ by IL-$1{\beta}$ or TNF-$\alpha$stimulation was assayed by Western blot analysis. The phosphorylation of $I{\kappa}B{\alpha}$ was evaluated by Western blot analysis after pre-treating cells with proteasome inhibitor followed by IL-$1{\beta}$ or TNF-$\alpha$ stimulation. The basal level of IKK $\alpha$ expression was evaluated by Western blot analysis. Results: $I{\kappa}B{\alpha}$ and $I{\kappa}B{\alpha}$ was rapidly degraded after 5 minutes of incubation with IL-$1{\beta}$ or TNF-$\alpha$ in BEAS-2B, A549, and NCI-H157 cells. The activation of NF-${\kappa}B{\alpha}$ and the induction of IL-8 and TNF-$\alpha$ mRNA expression were observed by IL-$1{\beta}$ or TNF-$\alpha$ stimulation in these cells. In contrast, neither the changes in NF-${\kappa}B/I{\kappa}B$ pathway nor IL-8 and TNF-$\alpha$mRNA expression was induced by IL-$1{\beta}$ or TNF-$\alpha$ stimulation in NCI-H719 cells. IL-$1{\beta}$ and TNF-$\alpha$-induced $I{\kappa}B$ phosphorylation was observed in BEAS-2B, A549, and NCI-H157 cells, but not in NCI-H719 cells. The basal level of IKK$\alpha$ expression was not different between cell. Conclusion : NF-${\kappa}B/I{\kappa}B$ pathway plays an important role in the expression of pro-inflammatory cytokine in most lung epithelial cells. The absence of the effect on NF-${\kappa}B/I{\kappa}B$ pathway in NCI-H719 cells sæms to be due to the defect in the intracellular signal transduction pathway upstream to IKK.

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Expression of Phospholipase C Isozymes in Human Lung Cancer Tissues (인체 폐암조직에서 Phospholipase C 동위효소의 발현양상)

  • Hwang, Sung-Chul;Mah, Kyung-Ae;Choi, So-Yeon;Oh, Yoon-Jung;Choi, Young-In;Kim, Deog-Ki;Lee, Hyung-Noh;Choi, Young-Hwa;Park, Kwang-Ju;Lee, Yi-Hyeong;Lee, Kyi-Beom;Ha, Mahn-Joon;Bae, Yoon-Su
    • Tuberculosis and Respiratory Diseases
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    • v.49 no.3
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    • pp.310-322
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    • 2000
  • Background : Phospholipase C(PLC) plays an important role in cellular signal transduction and is thought to be critical in cellular growth, differentiation and transformation of certain malignancies. Two second messengers produced from the enzymatic action of PLC are diacylglycerol (DAG) and inositol 1, 4, 5-trisphosphate (IP3). These two second messengers are important in down stream signal activation of protein kinase C and intracellular calcium elevation. In addition, functional domains of the PLC isozymes, such as Src homology 2 (SH2) domain, Src homology 3 (SH3) domain, and pleckstrin homology (PH) domain play crucial roles in protein translocation, lipid membrane modificailon and intracellular memrane trafficking which occur during various mitogenic processes. We have previously reported the presence of PLC-${\gamma}1$, ${\gamma}2$, ${\beta}1$, ${\beta}3$, and ${\delta}1$ isozymes in normal human lung tissue and tyrosine-kinase-independent activation of phospholipase C-${\gamma}$ isozymes by tau protein and AHNAK. We had also found that the expression of AHNAK protein was markedly increased in various mstologic types of lung can∞r tissues as compared to the normallungs. However, the report concerning expression of various PLC isozymes in lung canærs and other lung diseases is lacking. Therefore, in this study we examined the expression of PLC isozymes in the paired surgical specimens taken from lung cancer patients. Methods : Surgically resected lung cancer tissue samples taken from thirty seven patients and their paired normal control lungs from the same patients, The expression of various PLC isozymes were studied. Western blot analysis of the tissue extracts for the PLC isozymes and immunohistochemistry was performed on typical samples for localization of the isozyme. Results : In 16 of 18 squamous cell carcinomas, the expression of PLC-${\gamma}1$ was increased. PLC-${\gamma}1$ was also found to be increased in all of 15 adenocarcinoma patients. In most of the non-small cell lung cancer tissues we had examined, expression of PLC-${\delta}1$ was decreased. However, the expression of PLC-${\delta}1$ was markedly increased in 3 adenocarcinomas and 3 squamous carcinomas. Although the numbers were small, in all 4 cases of small cell lung cancer tissues, the expression of PLC-${\delta}1$ was nearly absent. Conclusion : We found increased expression of PLC-${\gamma}1$ isozyme in lung cancer tissues. Results of this study, taken together with our earlier findings of AHNAK protein-a putative PLD-${\gamma}$, activator-over-expression, and the changes observed in PLC-${\delta}1$ in primary human lung cancers may provide a possible insight into the derranged calcium-inositol signaling pathways leading to the lung malignancies.

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Structural Adjustment of Domestic Firms in the Era of Market Liberalization (시장개방(市場開放)과 국내기업(國內企業)의 구조조정(構造調整))

  • Seong, So-mi
    • KDI Journal of Economic Policy
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    • v.13 no.4
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    • pp.91-116
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    • 1991
  • Market liberalization progressing simultaneously with high and rapidly rising domestic wages has created an adverse business environment for domestic firms. Korean firms are losing their international competitiveness in comparison to firms from LDC(Less Developed Countries) in low-tech industries. In high-tech industries, domestic firms without government protection (which is impossible due to the liberalization policy and the current international status of the Korean economy) are in a disadvantaged position relative to firms from advanced countries. This paper examines the division of roles between the private sector and the government in order to achieve a successful structural adjustment, which has become the impending industrial policy issue caused by high domestic wages, on the one hand, and the opening of domestic markets, on the other. The micro foundation of the economy-wide structural adjustment is actually the restructuring of business portfolios at the firm level. The firm-level business restructuring means that firms in low-value-added businesses or with declining market niches establish new major businesses in higher value-added segments or growing market niches. The adjustment of the business structure at the firm level can only be accomplished by accumulating firm-specific managerial assets necessary to establish a new business structure. This can be done through learning-by-doing in the whole system of management, including research and development, manufacturing, and marketing. Therefore, the voluntary cooperation among the people in the company is essential for making the cost of the learning process lower than that at the competing companies. Hence, firms that attempt to restructure their major businesses need to induce corporate-wide participation through innovations in organization and management, encourage innovative corporate culture, and maintain cooperative labor unions. Policy discussions on structural adjustments usually regard firms as a black box behind a few macro variables. But in reality, firm activities are not flows of materials but relationships among human resources. The growth potential of companies are embodied in the human resources of the firm; the balance of interest among stockholders, managers, and workers of the company' brings the accumulation of the company's core competencies. Therefore, policymakers and economists shoud change their old concept of the firm as a technological black box which produces a marketable commodities. Firms should be regarded as coalitions of interest groups such as stockholders, managers, and workers. Consequently the discussion on the structural adjustment both at the macroeconomic level and the firm level should be based on this new paradigm of understanding firms. The government's role in reducing the cost of structural adjustment and supporting should the creation of new industries emphasize the following: First, government must promote the competition in domestic markets by revising laws related to antitrust policy, bankruptcy, and the promotion of small and medium-sized companies. General consensus on the limitations of government intervention and the merit of deregulation should be sought among policymakers and people in the business world. In the age of internationalization, nation-specific competitive advantages cannot be exclusively in favor of domestic firms. The international competitiveness of a domestic firm derives from the firm-specific core competencies which can be accumulated by internal investment and organization of the firm. Second, government must build up a solid infrastructure of production factors including capital, technology, manpower, and information. Structural adjustment often entails bankruptcies and partial waste of resources. However, it is desirable for the government not to try to sustain marginal businesses, but to support the diversification or restructuring of businesses by assisting in factor creation. Institutional support for venture businesses needs to be improved, especially in the financing system since many investment projects in venture businesses are highly risky, even though they are very promising. The proportion of low-value added production processes and declining industries should be reduced by promoting foreign direct investment and factory automation. Moreover, one cannot over-emphasize the importance of future-oriented labor policies to be based on the new paradigm of understanding firm activities. The old laws and instititutions related to labor unions need to be reformed. Third, government must improve the regimes related to money, banking, and the tax system to change business practices dependent on government protection or undesirable in view of the evolution of the Korean economy as a whole. To prevent rational business decisions from contradicting to the interest of the economy as a whole, government should influence the business environment, not the business itself.

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