• Journal of Embryo Transfer
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• v.21 no.2
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• pp.157-162
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• 2006

It is well known that unidentified factors in sera, hormones and growth factors promote the proliferation of granulosa cells and nuclear maturation of bovine COCs (cumulus oocytes complexes) in vitro. Attempts had been developed the simple composition of culture media and similar system to in vivo conditions has been applied. In the present study, we investigated the effect of FGF (fibroblast growth factor) on in vitro maturation and in vitro development of Hanwoo COCs. When the COCs were matured in HPM 199 (Inst. of Functional peptide, Japan) containing 0.1, 1 and 10 ng/ml FGF for 24 hr, maturation rates to metaphase II ($70.0{\sim}75.0%$) were significantly higher (p<0.05) than that of control group (0 ng/ml FGF, 37.5%). When matured COCs with FGF were cultured in maturation medium after in vitro fertilization, developmental rates to blastocysts were 9.5, 0 and 2.9%, respectively, compared to 25.0% of the control group (p<0.05). When the matured COCs with FGF were cultured in HPM 199 (IFP971, Inst. of Functional peptide, Japan) containing 10% FBS, 0.8% BSA or 0.1% PVA (polyvinyl alcohol), the blastocyst formation rates were 12.4, 12.8 and 8.5%, respectively, while the rates of matured COCs with FGF and cultured with IVMD and IVD (Inst. of Functional peptide, Japan) without serum were 38.4% and 34.8%, respectively (p<0.05). These results suggested that FGF is available for in vitro maturation of bovine COCs and is not suitable for in vitro development, but further investigation would be need for finding the synergistic autocrine/paracrine fashion of other growth factors in early bovine embryo development.

• Korean Journal of Environmental Agriculture
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• v.24 no.3
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• pp.270-279
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• 2005

It is important to understand and evaluate the environmental impacts of rice cultivation for developing environmentally-friendly agriculture because rice is main crop in Korea and rice cultivation have both functions of water pollution and purification with environmental and cultivation conditions. This paper presents the evaluation of nitrogen impact by rice cultivation on water system. A simple protocol was proposed to assess the potential amount of nitrogen outflow from paddy field and most of parameters affect on the nitrogen outflow from paddy field such as the amount of fertilizer application, water balance, the quality and quantity of irrigation water, soil properties, nitrogen turnover in the soil and cultivation method were considered. To develop the protocol, coefficients for parameters affected nitrogen turnover and outflow were gotten and summarized by comparison and analysis of all possible references related, and by additional experiments at field and laboratory. And potential amount of nitrogen input and output by water in paddy field were estimated with the protocol at the conditions of the nitrogen contents of irrigation water, amount of fertilizer application, and irrigation methods. Where irrigation water was clean, below 1.0 mg $L^{-1}$ of nitrogen concentration, rice cultivation polluted nearby watershed. At the conditions of 2.0 mg $L^{-1}$ of nitrogen concentration, 110 kg $ha^{-1}$ of nitrogen fertilizer application and flooding irrigation, rice cultivation had water pollution function, but it had water purification function with intermittent irrigation. At the conditions of 3.0 mg $L^{-1}$ of nitrogen concentration and 110 kg $ha^{-1}$ of nitrogen fertilizer application, rice cultivation had water purification function, but that had water pollution function with 120 kg $ha^{-1}$ of nitrogen application. Where irrigation water was polluted over 6.0 mg $L^{-1}$ of nitrogen, it was evaluated that rice cultivation had water purifying effect, even though the amount of nitrogen application was 120 kg $ha^{-1}$.

• Korean Journal of Ecology and Environment
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• v.43 no.1
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• pp.129-135
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• 2010

The relationship between rainfall variable and zooplankton dynamics was studied in the Upo wetland, an ecosystem of international importance. Water sampling was conducted on biweekly basis from January 2002 to December 2007 in the study site. The annual average of total rainfall was 1,324 mm during the study period. Total rainfall amount in 2003 (1,766 mm) was unusually high, while total rainfall amount in 2005 (975 mm) was exceptionally lower than the average. Most of basic limnological parameters (water temperature, dissolved oxygen, pH, conductivity and turbidity) in the study site were greatly influenced by the flooding events and rainfall amounts in summer. There were statistically significance between seasonal and inter-annual differences in zooplankton abundance and the total rainfall amount (ANOVA, P<0.05). Zooplankton abundance was high in summer (mean${\pm}$s.d.: $1,594{\pm}1,598\;Ind.\;L^{-1}$) and low in winter ($246{\pm}234\;Ind.\;L^{-1}$. The 47% of annual total zooplankton abundance in the study site were observed in summer. The seasonal pattern of rotifers was similar to that of total zooplankton. This reflected the fact that rotifers strongly dominated and occupied ca. 65% the total zooplankton abundance (annual mean: $398{\pm}1,139\;Ind.\;L^{-1}$, n=149), followed by cladocerans ($65{\pm}140\;Ind.\;L^{-1}$) and copepods ($58{\pm}84\;L^{-1}$). Planktonic rotifers such as Keratella cochlearis, Polyarthra spp. and Brachionus calyciflorus were dominant from winter to spring and attached rotifers such as Lecane spp., Monostyla spp. and Trichocerca spp., observed commonly from spring to fall. Among the environmental variables considered, rainfall in summer seemed to play the most important role in determining characteristics of zooplankton community dynamics in the Upo wetland.

• Journal of Life Science
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• v.26 no.1
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• pp.101-108
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• 2016

The aim of this study was to evaluate the relationships between the expression of Heat shock protein70 (HSP70), Raf-1 and Bcl-2-associated athanogene-1 (BAG1) protein in diffuse type gastric carcinoma and examine association of HSP70, Raf-1 and BAG1 expression with various clinic-pathological factors and survival. Heat shock protein70 is induced in the cells in response to various stress conditions, including carcinogens. Overexpression of heat shock protein 70 has been observed in many types of cancer. The proto-oncoprotein Raf is pivotal for mitogen-activated protein kinase (MAPK) signaling, and its aberrant activation has been implicated in multiple human cancers. Overexpression of BAG1 protein has been documented in some type of human cancer. BAG1 has been reported to interact with protein involved with a variety of signal pathway, and regulation of cell differentiation, survival and apoptosis. These interaction partners include HSP70 and Raf-1. The percentage of tumors exhibiting HSP70 positivity was significantly in cases of positive lymph node metastasis (64.9%) compared to cases without lymph node metastasis (35.1%, p=0.007). HS70 expression was correlated with pathological N-stage (p=0.006). Expression of BAG1 was detected in the majority of diffuse type gastric carcinoma tissues (71.7%), especially in younger patients (80% vs 52.6%, p=0.035). Furthermore BAG1 expression was correlated with tumor size (p=0.020). Raf-1 expression was found to be significantly associated with tumor size (p=0.005). The result indicate that HSP70 was significantly correlated the progression of diffuse type gastric cancer. Expression of BAG1 and Raf-1 may be used as diagnostic markers for gastric carcinoma.

• Convergence Security Journal
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• v.15 no.6_1
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• pp.79-92
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• 2015

It is required to expand area of inter-Korean economic cooperation, being limited to non-military field, to military field and then, to positively promote arms control in order to establish foundation for peaceful reunification in Korean peninsula. Reasons why arms control has not been promoted between South and North Korea in the meantime were such original factors as follows; (1) limit of confidence building between the South and the North, (2) functional limit of arms control itself, (3) institutional structural limit between the South and the North, (4) environmental limit at home and abroad. It is necessary to get out from existing frame and to seek a new paradigm in order to overcome above factors and to realize arms control between the South and the North. First, it is required to have prior political dialog at the South-North high-level talks in order to promote arms control and to exercise 'strategic flexibility' during negotiation and promotion process. For this, 'flexible reciprocity' has to be adopted in compliance with situation and conditions. Second, it is necessary to get out from existing principle of 'confidence building in advance and arms reduction later' but to seek the 'simultaneous driving principle of confidence building and arms reduction' as an eclectic approach. Namely, based on reasonable sufficiency, it is required to promote military confidence building and limited arms reduction in parallel, which is a lower level of arms control. Third, as an advisory body of Prime Minister's Office, it is necessary to install an organization exclusively responsible for arms control and to positively handle arms control issue from the standpoint of national policy strategy. If the South-North high-level talks take place, it is necessary to organize and operate 'South-North Joint Arms Control Promotion Board (tentative name)'. Fourth, it is required to exercise more active diplomatic competence in order to create national consensus on necessity of arms control for peaceful reunification and to form more favorable international environment. Especially, it is necessary to think about how to solve nuclear issue of North Korea together in collaboration with international society and how to maintain balance between ROK-US alliance and Sino-Korean cooperation relations.

• Journal of the Korean Geographical Society
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• v.41 no.2 s.113
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• pp.212-226
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• 2006

Surface data generally represent continuous distribution of geographical or social phenomena of a region in urban analysis. Instances include distribution of temperature, population of region, and various distributions related to human activities. When spatial data are given in the form of surface, surface comparison is required as a way of comprehending the surface change or the relationship between two surfaces. As for previous approaches of surface comparison, there are visualization, quantitative methods and qualitative method. All those approaches, however, show the difference between two surfaces in a limited way. Especially, they are not able to distinguish spatial difference between two surfaces. To overcome such problem, this paper proposes a method of comparing two surfaces in terms of their spatial structure. Main concept of the method comes from earth moving problem and the method is named minimum surface transformation, here. When a surface is transformed into another, total surface volume moved in the process of transformation should be the minimum. Both quantitative and spatial differences between two surfaces are evaluted by total surface volume moved and the distribution of moved surface volume of each cell respectively. The method is applied to hypothetical and actual data. From the former, it is understood that the method explains how two surfaces are quantitatively and spatially different. The result of the latter shows that moved total surface volume decreases as time goes by which fits the actual situation that population change rate gets smaller. Concerning the other measure of surface difference, the distribution of $X_{ij}$ describes detailed flow of surface volume than that of simply subtracting surface volume by indicating to what direction the population change occurs.

• Journal of Oral Medicine and Pain
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• v.34 no.3
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• pp.261-276
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• 2009

Lactacystin, a microbial natural product synthesized by Streptomyces, has been commonly used as a selective proteasome inhibitor in many studies. Proteasome inhibitors is known to be preventing the proliferation of cancer cells in vivo as well as in vitro. Furthermore, proteasome inhibitors, as single or combined with other anticancer agents, are suggested as a new class of potential anticancer agents. This study was undertaken to examine in vitro effects of cytotoxicity and growth inhibition, and the molecular mechanism underlying induction of apoptosis in SCC25 human tongue sqaumous cell carcinoma cell line treated with lactacystin. The viability of SCC25 cells, human normal keratinocytes (HaCaT cells) and human gingiva fibroblasts (HGF-1 cells), and the growth inhibition of SCC25 cells were assessed by MTT assay and clonogenic assay respectively. The hoechst staining, hemacolor staining and TUNEL staining were conducted to observe SCC25 cells undergoing apoptosis. SCC25 cells were treated with lactacystin, and Western blotting, immunocytochemistry, confocal microscopy, FAScan flow cytometry, MMP activity, and proteasome activity were performed. Lactacystin treatment of SCC25 cells resulted in a time- and does-dependent decrease of cell viability and a does-dependent inhibition of cell growth, and induced apoptotic cell death. Interestingly, lactacytin remarkably revealed cytotoxicity in SCC25 cells but not normal cells. And tested SCC25 cells showed several lines of apoptotic manifestation such as nuclear condensation, DNA fragmentation, the reduction of MMP and proteasome activity, the decrease of DNA contents, the release of cytochrome c into cytosol, the translocation of AIF and DFF40 (CAD) onto nuclei, the up-regulation of Bax, and the activation of caspase-7, caspase-3, PARP, lamin A/C and DFF45 (ICAD). Flow cytometric analysis revealed that lactacystin resulted in G1 arrest in cell cycle progression which was associated with up-regulation in the protein expression of CDK inhibitors, $p21^{WAF1/CIP1}$ and $p27^{KIP1}$. We presented data indicating that lactacystin induces G1 cell cycle arrest and apoptois via proteasome, mitochondria and caspase pathway in SCC25 cells. Therefore our data provide the possibility that lactacystin could be as a novel therapeutic strategy for human tongue squamous cell carcinoma.

• Sleep Medicine and Psychophysiology
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• v.2 no.2
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• pp.156-164
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• 1995

Objectives : Patients with obstructive sleep apnea syndrome(OSAS) often complain of nocturnal enuresis. There are a few reports that OSAS patients have altered renal function, and there are some evidences that the increased release of atrial natriuretic peptide(ANP) may be involved in the pathogenesis of nocturnal urinary symptoms of OSAS patients. In this study, we measured plasma ANP concentrations during waking and sleep in OSAS patients and normal controls to investigate whether there were differences of ANP concentrations between OSAS patients and normal subjects. Methods : 27 patients with OSAS and 10 normal subjects were studied. All subjects underwent a full-night polysomnographic study. Venous blood samples were separately drawn during waking and sleep. Plasma ANP concentrations were measured using radioimmunoassay. Results : In OSAS patients, ANP concentrations during sleep($122.9\;{\pm}\;29.9pg/ml$) were significantly higher than ANP concentrations during waking($60.2\;{\pm}\;5.8pg/ml$)(p < 0.05). However, in normal subjects, there was no significant difference between ANP concentrations during waking($59.2\;{\pm}\;5.7pg/ml$) and sleep($69.6\;{\pm}\;3.0pg/ml$)(p > 0.05). There was no significant difference of ANP concentrations during waking between OSAS patients($60.2\;{\pm}\;5.8pg/ml$) and normal controls($59.2\;{\pm}\;5.7pg/ml$)(p > 0.05), and also there was no significant difference during sleep between OSAS patients($122.9\;{\pm}\;29.9pg/ml$) and normal subjects($69.6\;{\pm}\;3.0pg/ml$)(p > 0.05). Plasma ANP concentrations during sleep showed significant positive correlations with apnea index(r = 0.3846, p < 0.05) and respiratory disturbance index(r = 0.3939, p < 0.05) in OSAS patients. Conclusion : These data suggest that, in OSAS patients, plasma ANP concentrations during sleep are significantly higher than plasma ANP concentrations during waking, and there is a positive correlation between the plasma ANP concentration during sleep and the severity of sleep apnea.

• Tuberculosis and Respiratory Diseases
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• v.50 no.4
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• pp.415-425
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• 2001

Background : The correlation between the high resolution computed tomography(HRCT) emphysema score and the physiologic parameters including resting and exercise pulmonary function test was investigated in 14 patients($60.6{\pm}10.3$ years) with pulmonary emphysema. Methods : The patients underwent a HRCT, a resting pulmonary function test, and incremental exercise testing(cycle ergometer, 10 W/min). Computed tomography scans were obtained on a GE highlight at 10 mm intervals using 10 mm collimation, from the apex to the base after a full inspiration. The emphysema scores were determined by a CT program 'Density mask' outlining the areas with attenuation values less than -900 HU, indicating the emphysema areas, and providing an overall percentage of lung involvement by emphysema. Results : Among the resting PFT parameters, only the diffusing capacity(r=-0.75) and $PaO_2$ (r=-0.66) correlated with the emphysema score(p<0.05). Among the exercise test parameters, the emphysema score correlated significantly with the maximum power(r=-0.74), maximum oxygen consumption(r=-0.68), anaerobic threshold(V-slope method: r=-0.69), maximal $O_2$-pulse(r=-0.73), and the physiologic dead space ratio at the maximum workload(r=-0.80)(p<0.01). Conclusion: We could find that exercise testing parameters showed a much better correlation with the HRCT emphysema score, which is known to have a good correlation with the pathologic severity than the resting PIT parameters. Therefore it is suggested that exercise testing is superior to resting PIT for estimating in the estimation of the physiologic disturbance in emphysema patients.

• Journal of The Korean Association For Science Education
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• v.38 no.5
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• pp.705-720
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• 2018

The purpose of this study is to shed light on the meaning and value of interest (in Korean 'Jae-mi') in science education through literature analysis. Literature analyses were conducted on literature related to interest in various fields such as Korean language, psychology, philosophy, and education. Specifically, this study discussed the meaning of interest, the characteristics of the context of experiencing interest, the educational value of interest in science education, and the direction of science education to realize the value of interest. First, it was found that interest is an experience of emotional activation that can be felt through interaction with a specific object, and it is an emotional experience caused by the complex combination of various psychological factors, which is oriented sense, relationship, self, and object. Second, to understand the context of experience of interest, we conducted a topic modeling analysis with 1173 research articles related to interest. As a result of the analysis, it was confirmed that the context of interest is closely related with playfulness. And we addressed that this kind of playfulness is also found in science. Third, the educational values of interest in science education were discussed. In science education, fun is not only an instrumental value to induce science learning behavior, it is also one of the universal experiences that learners feel lively in science teaching-learning, and driving force of individual students' emotional development related to science. The students' active attitude to feel interest lead to creative thinking and action. Finally, we argued that the interest that should be aimed in science education should be active interest and experienced at trial and error, not passive interest induced by external stimuli. And science education culture should be encouraged to respect those who enjoy science. In particular, this study discussed the importance of each student's unique interest experience based on the philosophy of philosopher Deleuze (1976).