• Title/Summary/Keyword: Control mechanism

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Effects of Removal Times of Transplanted Pituitary Gland on Induction of Ovulation and Levels of Estrogen and Progesterone in Immature Rats (미성숙 쥐에 이식한 뇌하수체의 경시별제거가 배란유도와 Estrogen 및 Progesterone수준에 미치는 영향)

  • Lee, J. H.;Kim, Y. H.;Lee, W.
    • Journal of Embryo Transfer
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    • v.2 no.1
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    • pp.36-46
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    • 1987
  • The present work was designed to understand the mechanism of superovuiation and the cause of early embryo loss and Implantation failure in the superovulating immature female rats which were elaborated by a pituitary gland transplantation. A pituitary gland obtained from the orchidectomized rats was transplanted under the right kidney capsule of 28 day old female rats (PGT group) on the starting day of experiment which was designated as Day 2. The grafted pituitary glands were removed at 6h (RPGT 6h group), 12h (RPGT 12hgroup) and 24h (RPGT 24h group) after the transplantation. Control rats were treated with 41U PMSG on Day 2 (PMSG group). The estrous cycle and the levels of plasma progesterone and estradiol-17$\beta$ were observed on Day 0, Day 5, respectively. The implantation sites, the weights of ovary and uterus, and the number of corpora lutea were examined in all group on Day 8. The resuft obtained were summarized as follows: 1. The percentages of the number of the rats in proestrus and estrus were 93.0%, 82.6%, 0%, 90.7% and 89.5% in PMSG, PGT, RPGT6h, RPGT12h and RPGT24h group, respectively. The synchronization of estrus cycle was dchieved in all groups. 2. The mating rates of each group were 80.2, 75.0, 0, 56.4, 57.8% in PMSG, PGT, RPGT6h, RPGT12h, RPGT24h group, respectively. 3. The numbers of copora lutea on Day 8 were 47.1 i 4.9, 18.1 $\pm$0.5, 14.1 i 0.3 and 8.9 $\pm$ 0.3 in PGT, RPGT24h, RPGTl2h and PMSG group, respectively. There were signIficantly difference between all groups (P<0.05). 4. The numbers of implantation sites (18.1 +- 4.0) in PGT group on Day 8 were higher than those of PMSG (8.5 $\pm$ 2.5), RPGT 12h (9.8 i 0.2) and RPGT 24h group (10.8 i 0.2) (P<0.05). 5. The ovarlan weights in PGT (95.2 $\pm$ 14.3mgIlOOg BW), RPGT 12h (51.7 $\pm$ 0.6mgIlOOg BW), and RPGT24h (57.9 $\pm$ 0.9mg/l00g 8W) groups were significantly higher than those of PMSG group (30.4 $\pm$7.4mg/l00g BW) (P<0.05). 6. The uterine weights in PMSG (672.4 $\pm$ 4.7mg/l00g 8W), and PGT (660.7 $\pm$7.8mg/l00g BW) groupswere greater than those of RPGT 12h (403.0 $\pm$ 1.lmg/lOOg BW) and RPGT 24h (490.1 $\pm$ 0.9mg/l00g BW) group (P<0.05). 7. The plasma progesterone levels in PGT groups (15 lng/ml) on Day 5 were higher than those of PMSG (83ng/ml), RPGT 12h (S7ng/ml), RPGT24h (8lng/ml) group (P<0.05). 8. The plasma estradiol-17$\beta$ levels in PMSG group (lBSpg/ml) on Day S were higher than those of RPGT 24h (l3pg/ml) group (P<0.05). But estradiol-17$\beta$ levels in PGT and RPGT 12h group were too low to discuss.

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Anti-obesity effect of Polygala tenuifolia (원지(Polygala tenuifolia)의 항비만 효과)

  • Hwang, Ju-Young;Wu, Yong-Xiang;Hwang, Dae-Il;Bae, Suk-Jae;Kim, Taewan
    • Food Science and Preservation
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    • v.21 no.1
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    • pp.97-106
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    • 2014
  • This study was performed in order to investigate the anti-obesity effect of Polygala tenuifolia on lipid mechanism in 3T3-L1 adipocytes. The chemical composition of the P. tenuifolia was analyzed in order to assess its nutritional value. Total dietary fiber was the highest among the proximate component of the P. tenuifolia. These results showed that the P. tenuifolia may be used as a potential functional ingredient for anti-obesity effect. Intracellular lipid droplets in the adipocyte were stained with oil-red O dye and quantified. In comparison to the control, lipid accumulation was significantly decreased by 40.1% and 22.4% when treated with the water extract and 70% EtOH extract of the P. tenuifolia at the concentration of $10{\mu}g/mL$, respectively. The anti-adipogenic effect of the water extract was stronger than that of the 70% EtOH extract. The gene expression levels were measured via Western blot and real-time PCR. As a result, the water extract was found to have decrease the gene expression of SREBP-1c, PPAR, $C/EBP{\alpha}$, FAS, ACC in a dose-dependent manner. These indicate that the water extract inhibits pre-adipocyte differentiation and adipogenesis by blocking the SREBP-1c gene expression in 3T3-L1 cells. Therefore, P. tenuifolia can be used as an effective anti-obesity agent.

Pro-apoptotic Effects of Platycodin D Isolated from Platycodon grandiflorum in Human Leukemia Cells (도라지 유래 사포닌 platycodin D에 의한 인체 백혈병세포의 apoptosis 유도)

  • Park, Sang Eun;Lee, Su Young;Shin, Dong Yeok;Jeong, Jin-Woo;Jin, Myung Ho;Park, Seon Young;Chung, Yoon Ho;Hwang, Hye Jin;Hong, Sang Hoon;Choi, Yung Hyun
    • Journal of Life Science
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    • v.23 no.3
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    • pp.389-398
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    • 2013
  • Platycodin D is a major constituent of triterpene saponins, which is found in the root of Platycodon grandiflorum, Platycodi Radix, which is widely used in traditional Oriental medicine for the treatment of many chronic inflammatory diseases. Several pharmacological effects of this compound have been reported recently, such as anti-inflammation, immunogenicity, anti-adipogenesis, lowered cholesterol, and anti-cancer activity. However, the mechanism by which this action occurs is poorly understood. In this study, we found that platycodin D greatly increased the potential of the anti-proliferative effect in various cancer cell lines. Our data revealed that platycodin D treatment resulted in a time- and concentration-response growth inhibition of U937 cells by inducing apoptosis, as evidenced by the formation of apoptotic bodies, chromatin condensation, and the accumulation of cells in the sub-G1 phase. Apoptosis induction of U937 cells by platycodin D correlated with an increase in the Bax/Bcl-2 ratio and caused the down-regulation of IAP family members. In addition, platycodin D treatment resulted in proteolytic activation of caspase-3, the concomitant degradation of poly(ADP-ribose) polymerases, and the collapse of the mitochondria membrane potential (${\Delta}{\Psi}_m$). However, the cytotoxic effects induced by platycodin D treatment were significantly inhibited by z-DEVD-fmk, a caspase-3 inhibitor, which demonstrated the important role that caspase-3 played in the observed cytotoxic effect. These findings suggest that platycodin D may be a potential chemotherapeutic agent for use in the control of human leukemia U937 cells. These findings also provided important new insights into possible molecular mechanisms of the anti-cancer activity of platycodin D.

Cartoon Criticism; The subject and the gaze based on Lacan' s theory otherness of vision : focusing on KUBRICK of Kang, Do-Ha (라캉의 시각의 타자성(대상 a)에 근거한 만화비평으로서의 주체와 응시 : 강도하의 큐브릭을 중심으로)

  • Yang, Seung-Kyu
    • Cartoon and Animation Studies
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    • s.26
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    • pp.79-108
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    • 2012
  • This thesis is on the purpose of seeking for the possibility of a mechanism in interpreting, analyzing and criticizing cartoons which are applied to the concept of "the gaze" based on "the otherness of vision", which states a pluralistic visual world. It proves that cartoons are in line with other art works that are the subject to "lack and desire"; the gaze, greets reality and acts as an important criterion of analyzing and criticizing the trend in contemporary art, in which the cartoon expresses the gaze in harmony within its work of art. In this thesis, the artist, Kang Doh-ha structuralized ambiguous and difficult forms of art as he has cumulated experimental minds by working in an indie cartoon plane for a long period of time. Among his works of art, he identified the "invisible world" through his piece "Kubrik". Therefore, he represented: a metaphor and a metonymy, an ambiguously situational expression, an intentional and emotional error, the structure of individuality and integration, and finally tension beyond its meaning through use of 'the gaze' that is both the cause and the subject of a desire in the visible world which Lacan academized when he interpreted and analyzed "Kubrik". The concept of the gaze can be used in a variety of ways to display one another's presence in relation each character, revealing a spot of lack by staring back at readers or audiences and furthermore, to analyze and criticize the hidden side of the art piece by critics. The most important details are the artist's gaze, which is seen in the eyes of the analysis and also his or her criticism of the cartoon, which functions as a metaphoric screen in which the subject himself or herself betrays the law of desires thus enabling the violent and cruel reality to be masked and indulged in plays. This will serve as an element that will lead into an art as well as control the degradation to just a piece of enjoyment with the cartoon remaining only within the visual world.

THE EFFECT OF BMP REGULATED SMAD PROTEIN ON ALKALINE PHOSPHATASE GENE EXPRESSION (Smad에 의한 alkaline phosphatase 유전자의 발현 조절기전)

  • Kim, Nan-Jin;Ryoo, Hyun-Mo;Kim, Hyun-Jung;Kim, Young-Jin;Nam, Soon-Hyeun
    • Journal of the korean academy of Pediatric Dentistry
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    • v.28 no.2
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    • pp.238-246
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    • 2001
  • Bone morphogenetic proteins(BMPs), members of the transforming growth factor $\beta$(TGF-$\beta$) superfamily were first identified as the factors that induce ectopic bone formation in vivo, when implanted into muscular tissue. Especially BMP-2 inhibits terminal differentiation of C2C12 myoblasts and converts them into osteoblast lineage cells. In the molecular mechanism of the signal transduction of TGF-$\beta$ and related factors, intracellular signaling proteins were identified as Smad. In previous study, it has been reported that Smad 1 and Smad 5, which belong to the R-Smad family mediate BMP signaling, were involved in the induction of osteoblast differentiation in C2C12 cells. To understnad the role of Smads involved in osteogenic transdifferentiation in C2C12 cell, in present study, after we stably transfected C2C12 cells with each. Smad(Smad 1,Smad 5) expression vector, cultured for 3 days and stained for alkaline phophatase activity. ALP activity positive cells appeared in the Smad 1, Smad 5 stably transfected cell even in the abscence of BMP. After transiently co-transfected C2C12 cells with each Smad expression vector and ALP promoter, it was examined that Smad 1 and Smad 5 expression vector had increased about 2 fold ALP promoter activity in the abscence of BMP. These result suggested that both Smad 1 and Smad 5 were involved in the intracellular BMP signals which induce osteoblast differentiation in C2C12 cells. The effect of BMP on C2C12 cells with Smad 1, Smad 5 transfected were studied by using northern blot analysis. the treatment of BMP upregulated ALP mRNA level in three groups, especially upregulation of ALP was larger in Smad 1, Smad 5 transfected cell than control group. Pretreatment with cycloheximide($10{\mu}g/ml$), a protein synthesis inhibitor resulted in blocking the ALP gene expression even in BMP(100ng/ml) treated cell. These results suggested that Smad increased the level of ALP mRNA via the synthesis of a certain transcriptional regulatory protein.

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Effect of Larva Extract of Allomyrina dichotoma on Carbon Tetrachloride-induced Hepatotoxicity in Mice (장수풍뎅이 유충 추출물이 사염화탄소에 의한 마우스의 간 손상에 미치는 영향)

  • Choi, Yong-Hwa;Lee, Ki-Yeol;Yang, Kyung-Mi;Jeong, Yun-Mi;Seo, Jung-Sook
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.35 no.10
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    • pp.1349-1355
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    • 2006
  • This study was conducted to investigate the effect of methanol extract of Allomyrina dichotoma larva (MEAL) on carbon tetrachloride $(CCl_4)-induced$ hepatotoxicity in mice. ICR mice were divided into 5 groups [Vehicle control, $CCl_4\;(10{\mu}g/g)$ alone, $CCl_4$ plus a low dose $(50{\mu}g/g)$ of MEAL, $CCl_4$ plus a high dose $(100{\mu}g/g)$ of MEAL]. Silymarin $(2{\mu}g/g)$ was used as the reference in the experiment. Administration of MEAL tended to decrease the serum alanine transaminase (ALT) activity induced by $CCl_4$ treatment in mice. Hepatic concentration of thiobarbituric acid-reactive substances (TBARS) in a high-dose group of diet decreased to the level of silymarin-treated group. Hepatic activity of glutathione S-transferase in MEAL-treated group was lower than that of $CCl_4-treated$ group. Serum concentration of bilirubin was significantly increased by $CCl_4$ treatment, but MEAL or silymarin recovered the level. These results suggest that MEAL may exert the protective effect against $CCl_4-induced$ hepatotoxicity in mice. However, more intensive studies would be needed to elucidate the protective mechanism of the beetle on hepatotoxicity of mice.

Microarray Analysis of Gene Expression in Rat Glioma after Ethanol Treatment (에탄올 처리에 의한 흰쥐 신경아교종(Glioma) 세포에서의 유전자 발현 - DNA 칩을 이용한 분석 -)

  • Lee, So Hee;Oh, Dong-Yul;Han, Jin-Hee;Choi, Ihn-Geun;Jeon, Yang-Whan;Lee, Joon-Noh;Lee, Tae Kyung;Jeong, Jong-Hyun;Jung, Kyung Hwa;Chai, Young-Gyu
    • Korean Journal of Biological Psychiatry
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    • v.14 no.2
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    • pp.115-121
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    • 2007
  • Objetives : Identification of target genes for ethanol in neurons is important for understanding its molecular and cellular mechanism of action and the neuropathological changes seen in alcoholics. The purpose of this study is to identify of altered gene expression after acute treatmet of ethanol in rat gliom cells. Methods : We used high density cDNA microarray chip to measure the expression patterns of multiple genes in cultured rat glioma cells. DNA microarrays allow for the simultaneous measurement of the expression of several hundreds of genes. Results : After comparing hybridized signals between control and ethanol treated groups, we found that treatment with ethanol increased the expression of 15 genes and decreased the expression of 12 genes. Upregulated genes included Orthodenticle(Drosophila) homolog 1, procollagen type II, adenosine A2a receptor, GATA bindning protein 2. Downregulated genes included diacylglycerol kinase beta, PRKC, Protein phosphatase 1, clathrin-associated protein 17, nucleoporin p58, proteasome. Conclusion : The gene changes noted were those related to the regulation of transcription, signal transduction, second messenger systems. modulation of ischemic brain injury, and neurodengeneration. Although some of the genes were previously known to be ethanol responsive, we have for the most part identified novel genes involved in the brain response to ethanol.

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The Mechanisms of Resistance to TNF in TNF-Sensitive Cancer Cells Transfected with TNF-$\alpha$ Gene Using Retroviral Vector (암세포에서 Retroviral Vector를 이용한 종양괴사인자 유전자 이입후 획득된 종양괴사인자 내성의 기전)

  • Lee, Hyuk-Pyo;Oh, Yeon-Mok;Yoo, Chul-Gyu;Kim, Young-Whan;Shim, Young-Soo;Han, Sung-Koo
    • Tuberculosis and Respiratory Diseases
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    • v.44 no.3
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    • pp.547-558
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    • 1997
  • Background : Tumor necrosis factor(TNF) has been considered as an important candidate for cancer gene therapy based on its potent anti-tumor activity. However, since the efficiency of current techniques of gene transfer is not satisfactory, the majorities of current protocols is aiming the in vitro gene transfer to cancer cells and re-introducing genetically modified cancer cells to hoot. In previous study, it was shown that TNF-sensitive cancer cells transfected with TNF-$\alpha$ cDNA would become highly resistant to TNF. Understanding the mechanisms of TNF-resistance in TNF-$\alpha$ gene transfected cancer cells would be an important step for improving the efficacy of cancer gene therapy as well as for better understandings of tumor biology. This study was designed to evaluate the role of new protective protein synthesis in the acquired resistance to TNF of TNF-$\alpha$ gene transfected cancer cells. Method : We transfected TNF-$\alpha$ c-DNA to WEHI164, a murine fibrosarcoma cell line, using retroviral vector(pLT12SN(TNF)) and confirm the expression of TNF with PCR, ELISA, MIT assay. Then we determined the TNF resistance of TNF gene transfected cells(WEHI164-TNF) and the changes of TNF sensitivities after treatments with actinomycin D(transcription inhibitor) and cycloheximide ( translation inhibitor). Results : WEHI164 which was sensitive to TNF became resistant to TNF after being transfected with TNF-$\alpha$ gene and the resistance to TNF was partially reversed after treatment with actinomycin D, but not with cycloheximide. Conclusion : The acquired resistance to TNF after TNF-$\alpha$ gene transfection may be associated with synthesis of some protective proteins.

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EFFECTS OF SUBINHIBITORY CONCENTRATIONS OF ANTIMICROBIAL AGENTS ON CELL SURFACE PROPERTIES AND VIRULENCE FACTORS OF MUTANS STREPTOCOCCI (아저해농도(亞沮害濃度)의 항균물질이 mutans streptococci의 세포표면성질과 독력인자에 미치는 영향)

  • Kim, Young-Jae;Hahn, Se-Hyun;Lee, Sang-Hoon;Jang, Ki-Taeg;Kim, Chol-Chul
    • Journal of the korean academy of Pediatric Dentistry
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    • v.31 no.4
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    • pp.605-616
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    • 2004
  • Subinhibitory concentrations (sub-MICs) refer to concentrations below minimum inhibitory concentrations (MICs). The antimicrobial agents may be present at relatively high concentration, at least higher than bacterial MIC and thereafter be deserted off a surface and function at sub-MICs, perhaps by interfering with bacterial metabolism. Consequently, the aim of this study was to determine the effects of growth, in the presence of sub-MICs of antimicrobial agents, on the cell surface properties and virulence factors of mutans streptococci and to investigate the efficacy of a chemical approach in vitro. Streptococcus mutans Ingbritt and Streptococcus sobrinus 6715-7 were used. Eight antimicrobial agents (Sanguinaria extract;SG, Chlorhexidine digluconate;CHX, Fluoride;F, Propolis;PP, Hydrogen peroxide;HP, Triclosan;TC, Sodium dodecyl sulfate;SDS Cetylpyridinium chloride; CC) were diluted serially in broth to determine MICs and to compare the growth rate, acid production, hydrophobicity, adhesion activity to saliva coated hydroxyapatite, glucan synthesis and cellular aggregation of experiment groups (in the presence of sub-MICs) with those of control (in the absence of antimicrobial agents). Sub-MICs of antimicrobial agents affected the growth of cells, hydrophobicity, and adhesion of bacteria to saliva coated hydroxyapatite and glucan synthesis. They also resulted in a significant reduction in pH after 12 hours (p<0.05). By cells pretreated with proteinase K, either the aggregation induced by antimicrobial agents was completely inhibited or the aggregation titers were markedly increased. According to the results of the present study, each antimicrobial agent at sub-MICs could affect similar as its known action mechanism and could continually inhibit cariogenic bacteria at such concentrations. Thus, the use of these antimicrobial agents would be one of the effective methods to prevent dental caries.

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Characterization and Functional Analysis of Obox4 during Oocyte Maturation by RNA Interference (생쥐의 난소와 난자에서의 Obox4의 동정과 RNAi를 이용한 기능연구)

  • Lee, Hyun-Seo;Lee, Kyung-Ah
    • Clinical and Experimental Reproductive Medicine
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    • v.34 no.4
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    • pp.293-303
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    • 2007
  • Objective: Previously, we identified differentially expressed genes between GV and MII stage mouse oocytes using ACP technology. When we study one of GV selective genes, Obox family, we found Obox4 mRNA expression in ovaries that has been reported as expressed exclusively in testis. Therefore, this study was conducted for characterization and functional analysis for Obox4. Methods: Expression of Obox4 mRNA was examined in gonads and oocytes by RT-PCR. To determine the role of Obox4 in oocyte maturation, Obox4 dsRNA was microinjected into the cytoplasm of GV oocytes followed by 16 h of incubation in the plain medium or by 24 h of incubation in the medium containing IBMX. After RNAi, phenotypes and maturation rates were observed, change in mRNA expression was evaluated, and chromosomal status was confirmed by orcein staining. Results: Obox4 has minimal expression in the ovary compared to that of the other family members. When oocytes were cultured for 16 h in M16 medium after RNAi, maturation rate was not changed significantly, compared with that of non-injected or buffer-injected control oocytes. Surprisingly, however, when oocytes were cultured for 24 h in M16 containing IBMX, in which oocytes were supposed to arrest at GV stage, Obox4 RNAi oocytes were advanced to MI and MII. Spindle structure was disappeared and the chromosomes were condensed in the oocytes after Obox4 RNAi. Conclusions: This is the first report on the expression of Obox4 in the ovary and oocytes. Results of the study suggest that Obox4 plays a crucial role in spindle formation and chromosome segregation during meiosis in oocytes. In addition, Obox4 may play an important role in cAMP-dependent signal cascades of GV-arrest in mouse oocytes.