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Analysis and Evaluation of the Content Relevance in the 7th National Primary Science Curriculum (제7차 초등학교 과학과 교육과정 내용의 적정성 분석 및 평가)

  • Lee Yang-Rak;Part Jae-Keun;Lee Bong-Woo;Han In-Ok
    • Journal of Korean Elementary Science Education
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    • v.24 no.3
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    • pp.214-225
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    • 2005
  • The purpose of this study was to examine the content relevance of the 7th national primary science curriculum and textbooks. To fulfill the purpose of the study, we 1) analyzed the 7th national science curriculum of Korea, Californian science standards, the national science curriculum of England and Japan, and current Korean and Japanese science textbooks, 2) conducted a nationwide survey to gather opinions from students, teachers, and professors of teachers colleges about the relevance of the science curriculum and textbooks. Main findings of this study are as follows: First, the science contents at each grade level should be determined by the students' characteristics, not by an equal portion rule among physics, chemistry, biology and earth science. Second, the excessive overlapping and repetition of contents due to the spiral curriculum should be avoid. Third, the number of topics at each grade level should be reduced, and the similar topics and themes should be integrated for students' deeper understanding. Fourth, the number of science concepts and activities should be reduced to an appropriate level considering the time allotment for science classes, teachers workload, laboratory conditions, etc. Fifth, differentiated curriculum, such as in-depth and supplementary course, should be described not in science contents, but in teaching and learning strategy.

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$17{\beta}$-estradiol Prevents the Expression of $CEBP{\alpha}$-mediated Adipocyte Marker Genes in Female Ovariectomized C57BL/6 Mice

  • Yoon, Mi-Chung;Jeong, Sun-Hyo
    • Biomedical Science Letters
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    • v.14 no.3
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    • pp.131-137
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    • 2008
  • Adipogenesis is a complex sequence of events that culminates in the differentiation of fibroblast-like preadipocytes into specialized lipid-filled adipocytes and also involves a cascade of expression of many transcription factors such as peroxisome proliferator-activated receptor ${\gamma}(PPAR{\gamma})$ and CCAAT/enhancer-binding proteins (C/EBPs). $PPAR{\gamma}$ and C/EBPs transcriptionally transactivate adipocyte specific genes, including fatty acid transport protein (FAT/CD36) and leptin. To determine whether $17{\beta}$-estradiol modulates $C/EBP{\alpha}$ actions on adipogenesis in high fat diet-fed female ovariectomized (OVX) C57BL/6 mice, mice were treated with $17{\beta}$-estradiol for 7 days and the effects of $17{\beta}$-estradiol on adipose tissue mass and expression of adipocyte specific gene as well as $C/EBP{\alpha}$ were measured. Compared to vehicle-treated OVX control mice, OVX mice treated with $17{\beta}$-estradiol for 7 days had lower adipose tissue weights that were similar to weights in high fat diet-fed sham-operated (Sham) mice. OVX mice showed the increased expression of $C/EBP{\alpha}$ mRNA compared with Sham mice. However, $17{\beta}$-estradiol treatment in OVX mice inhibited OVX induced-$C/EBP{\alpha}$ activation, indicating that $17{\beta}$-estradiol may act as an inhibitor of $C/EBP{\alpha}$ action. Moreover, $17{\beta}$-estradiol decreased mRNA levels of adipocyte marker genes, such as lipoprotein lipase, FAT/CD36 and leptin, to levels in Sham mice. These results suggest that down-regulation of adipogenesis by $17{\beta}$-estradiol may be due to reduced adipose $C/EBP{\alpha}$ activities in female OVX C57BL/6 mice.

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Partial Purification of Antioxidative Peptides from Gelatin Hydrolysates of Alaska Pollock Surimi Refiner Discharge

  • Heu, Min-Soo;Park, Chan-Ho;Kim, Hyung-Jun;Park, Jae-W.;Kim, Jin-Soo
    • Fisheries and Aquatic Sciences
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    • v.12 no.4
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    • pp.249-257
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    • 2009
  • This study is conducted to partially purify an antioxidative peptide in a two-step gelatin hydrolysate from Alaska pollock surimi refiner discharge, which was obtained by sequential treatment with Pronase E and Flavourzyme. The two-step gelatin hydrolysate was fractionated using chromatographic methods. Based on the same protein concentration of each fraction, the antioxidative activities (85.1-95.4%) of positive fractions fractionated by ion-exchange chromatography were higher than those (27.2-87.8%) from gel filtration. Then, further purification of the positive fractions was performed. Among them, the partially purified A1C1L2G1 and A1C1L2G2 fractions showed 96.2% and 85.1% inhibition, respectively, of linoleic acid peroxidation. The A1C1L2G1 fraction was composed of 15 kinds of amino acids and the predominant amino acids were proline, glycine and alanine. The results obtained in this study suggested that the fraction partially purified through chromatographic methods from the two-step gelatin hydrolysate of Alaska pollock surimi refiner discharge could be useful as a supplementary source for improving health functionality.

A Novel Anti-cancer Agent, SJ-8029, Inhibits Angiogenesis and Induces Apoptosis

  • Yi Eui-Yeun;Jeong Eun-Joo;Song Hyun-Seok;Kang Dong-Wook;Joo Jeong-Ho;Kwon Ho-Seok;Lee Sun-Hwan;Park Si-Kyung;Chung Sun-Gan;Cho Eui-Hwan;Kim Yung-Jin
    • Biomedical Science Letters
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    • v.12 no.3
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    • pp.161-170
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    • 2006
  • A new piperazine derivative, 8J-8029, is a synthetic anti-cancer agent which exhibits both microtubule and topoisomerase II inhibiting activities. In this study, we investigated the ability of 8J-8029 for anti-angiogenesis and apoptosis. 8J-8029 decreased the bFGF-induced angiogenesis in the CAM and the mouse Matrigel implants, in vivo. 8J-8029 inhibited the proliferation, migration, invasion, tube fonnation, and expression of MMP-2 in BAECs. In addition, 8J-8029 reduced the cell viability in HepG2 cells, caused the production of fragmented DNA and the morphological changes corresponding to apoptosis. 8J-8029 also elicited the release of cytochrome c and the activation of caspase-3. Taken together, these results suggest 8J-8029 may be a candidate for anti-cancer agent with the ability to inhibit the angiogenesis of endothelial cells and to induce the apoptosis of tumor cells.

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Novel Anti-Angiogenic Activity in Rubus coreanus Miquel Water Extract Suppresses VEGF-Induced Angiogenesis

  • Kim, Eok-Cheon;Kim, Hye Jin;Kim, Tack-Joong
    • Biomedical Science Letters
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    • v.20 no.4
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    • pp.209-220
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    • 2014
  • Vascular endothelial growth factor (VEGF) is a key factor involved in the induction of angiogenesis and has become an attractive target for anti-angiogenesis therapies. The purpose of this study was to elucidate the anti-angiogenic activity of Rubus coreanus Miquel water extract (RCME). Rubus coreanus Miquel has long been employed as a traditional medicine, and recent studies have demonstrated that it has measureable biological activities. Thus, we investigated for the first time the effect of RCME on angiogenesis and its underlying signaling pathways. The effects of RCME were tested on in vitro models of angiogenesis, namely, proliferation, migration, invasion and tube formation of human umbilical vein endothelial cells as well as an ex vivo model of vessel sprouting from the rat aorta in response to VEGF. We observed that VEGF-induced angiogenesis was strongly suppressed by RCME treatment compared to that of the control group. Moreover, we found that RCME inhibited VEGF-induced activation of matrix metalloproteinases and phosphorylation of extracellular signal-regulated kinase and p38, and also effectively inhibited phosphorylation of VEGF receptor 2. These results indicated that RCME inhibits angiogenesis by suppressing phosphorylation of the VEGF receptor and may be useful for the treatment of angiogenesis-dependent diseases such as cancer and diabetic retinopathy.

Biological Safety and Anti-hepatofibrogenic Effects of Brassica rapa (Turnip) Nanoparticle

  • Park, Dae-Hun;Li, Lan;Jang, Hyung-Kwan;Kim, Young-Jin;Jang, Ja-June;Choi, Yeon-Shik;Park, Seung-Kee;Lee, Min-Jae
    • Molecular & Cellular Toxicology
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    • v.5 no.4
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    • pp.317-322
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    • 2009
  • Hepatic fibrosis is one of chronic liver diseases which spread in worldwide and it has high risk to turn advanced cirrhosis and hepatocellualr carcinoma. Brassica family has been produced for commercial purpose and in Korea Brassica rapa (Turnip) is cultivated in Ganghwa County, Gyeonggi-do Korea and used for making Kimchi. Recently pharmacological effects of turnip have been known; diabete mellitus modulation, alcohol oxidization, and fibrosis inhibition. In previous study we found antifibrogenic effect of turnip water extract and in this study we made turnip nanoparticle to promote turnip delivery into liver. At the same time we assessed the biological safety of turnip nanoparticle. Thioacetamide (TAA) induced hepatic nodular formation and fibrosis (mean of fibrosis score: 4). However, 1% turnip nanoparticle inhibited TAA-induced hepatic nodular formation and fibrosis (mean of fibrosis score: 2-3). Activities of serum enzymes (aspartic acid transaminase (AST), alanine transaminase (ALT), and total bilirubin (T-Bil)), complete blood count (CBC), and the appearance of organs were not different from control and 1% turnip nanoparticle treatment. Conclusively 1% turnip nanoparticle significantly reduced TAA-induced hepatic fibrosis and was safe in 7-weeks feeding.

Functional Chemical Components in Protaetia brevitarsis Larvae: Impact of Supplementary Feeds

  • Yoon, Chul-Ho;Jeon, Seung-Ho;Ha, Yeon Jo;Kim, Sam Woong;Bang, Woo Young;Bang, Kyu Ho;Gal, Sang Wan;Kim, Il-Suk;Cho, Young-Son
    • Food Science of Animal Resources
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    • v.40 no.3
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    • pp.461-473
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    • 2020
  • The goal of this study was to evaluate the influence of various supplementary feeds on the chemical composition and production of bioactive substances in Protaetia brevitarsis larvae. The primary feed-oak-fermented sawdust-was supplemented with a variety of substances, including aloe, apple, banana, sweet persimmon (S. persimmon) and sweet pumpkin (S. pumpkin). Crude protein and fat content were the highest in the control and S. pumpkin group, respectively. Supplementary feeds increased the content of unsaturated fatty acids, except in the group receiving S. pumpkin, in which oleic acid was the most abundant (58.2%-64.5%). Free essential amino acids in larvae receiving supplementary aloe were higher compared with the control group except for Lys and His. Polyphenol and flavonoid contents and the antioxidant activities of ABTS and DPPH were higher in all treated groups compared with the control group. Although supplementary feeds led to a decreased crude protein content in the treated larvae when compared with the control group, these treatments generally improved the levels of unsaturated fatty acids and antioxidative activity. Therefore, we suggest that among the supplementary foods tested, aloe is a better resource for P. brevitarsis based on crude protein content, free amino acids and other bioactive compounds such as unsaturated fatty acids and antioxidants.

Efforts to obtain better rice seedlings performance under nontidal swamp land agro-ecosystem in south Sumatra, Indonesia

  • Suwignyo, Rujito A.;Sakagami, J.;Ehara, H.;Sulaiman, F.;Hasmeda, M.
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.50-50
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    • 2017
  • Swampland is a potential alternative land to be used in various agricultural production activities in Indonesia, because Indonesia have 33.41 million hectares of swamp land that consists of 13.28 million hectares nontidal swamp and million hectares 20.13 tidal swamp. In the province of South Sumatra, because of unpredictable water level in the field before planting, farmers have been doing agronomic adaptation method through the delay time of transplanting and forced to apply more than one the nursery practice with the combination of a floating nursery method and a dry-bed nursery method. This study was aimed to (1) evaluate the seedling growth and tillering pattern of several popular Indonesian rice varieties, and (2) look for alternative technologies to get a better rice seedlings under two nursery methods in the nontidal swamp land. In the first experiment, the seedling growth characteristics of five rice varieties (Ciherang, Inpara 5, Inpara 9, Inpari 29, and Inpari 30) was evaluated by two methods of nursery, i.e. floating nursery and dry-bed nursery. In the second experiment, rice variety of Inpari 30 was treated with Zn seed priming and foliar fertilizer of 2,300 ppm N at the nursery stage. Those treatments were combined with the time of seedling under floating and dry-bed nursery. The results of the first experiment showed that of the five varieties tested, dry-bed nursery method showed better seedling growth than floating nursery. This was indicated by high leaf number, tiller number, tillers pattern, shoot-root ratio and relative growth rate. Ciherang and Inpari 30 showed high tiller number, and they had produced tertiary tiller in the sixth week of observation. Moreover, shorter period of floating and dry-bed nursery in combination with the treatment of Zn seed priming and spraying seedling with foliar fertilizer N could improve the growth of seedlings.

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Effects of Epidermal Growth Factor and Insulin-like Growth Factor-I on Placental Amino Acids Transport Activities in Rats

  • Ono, Kenichiro
    • Proceedings of the Korean Society of Embryo Transfer Conference
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    • 2002.11a
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    • pp.34-36
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    • 2002
  • Epidermal growth factor (EGF) and insulin-like growth factor-I (IGF-I) have been shown to stimulate proliferation and differentiation of various somatic cells, including placental trophoblasts and also to enhance fetal growth and development when maternally administered. Since an increase of the expression of placental EGF and IGF-I receptors in rat, mouse, and human with the gestation advanced, both EGF and IGF-I were considered to play pivotal roles on fetal growth by regulating some function of placental cells. Amino acids are crucial importance for both maternal and fetal requirements of energy source and essential constituent of fetal mass during pregnancy. Impaired fetal and placental uptake of amino acids has been observed in several models of growth retardation in the rat. Amino acid is concentrated in the fetal side through active transport by amino acid transporters and is one of the important metabolic fuels for the fatal growth. Therefore, at first plasma amino acid concentrations in mothers and fetuses were measured as an index of uphill transport across the placenta associated with EGF and IGF-1. The EGF administration at the concentration of 0, 0.1, or 0.2 $\mu\textrm{g}$/g to pregnant rats from day 18 to 21 of gestation apparently increased fetal/maternal ratio of serum proline concentration and also fatal growth in EGF dose-dependent manner. When IGF-I in doses of 0, 1, 2, and 4 $\mu\textrm{g}$/g were administrated, the ratio of leucine, isoleucine, tryptophan, phenylalanine, tyrosine and also fetal growth significantly increased with a dose-dependent manner. These results suggested that EGF and IGF-I enhanced fatal growth by, as one of its possible mechanisms, promoting placental activity to transfer some amino acid supplies from the mother to the fetus in late pregnancy.

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Improving Effect of Silk Peptides on the Cognitive Function of Rats with Aging Brain Facilitated by D-Galactose

  • Park, Dong-Sun;Lee, Sun-Hee;Choi, Young-Jin;Bae, Dae-Kwon;Yang, Yun-Hui;Yang, Go-Eun;Kim, Tae-Kyun;Yeon, Sung-Ho;Hwang, Seock-Yeon;Joo, Seong-Soo;Kim, Yun-Bae
    • Biomolecules & Therapeutics
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    • v.19 no.2
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    • pp.224-230
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    • 2011
  • In order to develop silk peptide (SP) preparations possessing cognition-enhancing effect, several candidates were screened through in vitro assays, and their effectiveness was investigated in facilitated brain aging model rats. Incubation of brain acetyl-cholinesterase with SP-PN (1-1,000 ${\mu}g/ml$) led to inhibition of the enzyme activity up to 35%, in contrast to a negligible effect of SP-NN. The expression of choline acetyltransferase (ChAT) mRNA of neural stem cells expressing ChAT gene (F3.ChAT) was increased by 24-hour treatment with 10 and 100 ${\mu}g/ml$ SP-NN (1.35 and 2.20 folds) and SP-PN (2.40 and 1.34 folds). Four-week subcutaneous injections with D-galactose (150 mg/kg) increased activated hippocampal astrocytes to 1.7 folds (a marker of brain injury and aging), decreased acetylcholine concentration in cerebrospinal fluid by 45-50%, and thereby impaired learning and memory function in passive avoidance and water-maze performances. Oral treatment with SP preparations (50 or 300 mg/kg) for 5 weeks from 1 week prior to D-galactose injection exerted recovering activities on acetylcholine depletion and brain injury/aging as well as cognitive deficit induced by D-galactose. The results indicate that SP preparations restore cognitive functions of facilitated brain aging model rats by increasing the release of acetylcholine, in addition to neuroprotective activity.