• 한국동물학회지
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• 제32권4호
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• pp.305-313
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• 1989

The present investigation aims at inquiring into a possible target for the heat inactivation of SCK tumor cells by comparing the kinetics of cell survival, rate of protein synthesis, and DNA polymerase activity in the presence of heat protector or heat sensitirer. A possible conclusion to be drawn from the present experiment is that there is no direct correlation between cell death and decrease in the rate of protein synthesis, but that the loss of DNA polvmerase $\beta$ activity correlates quite well with cell inactivation. Thus, protein degrada-tion and/or abnormal protein synthesis causes cell inactivation innireuv, possibly by altering the cellular environment which in turn affects the DNA polymerase $\beta$ activity. Accordingly, further studies, dealing with the correlation between changes in the cellular environment and DNA polymerase $\beta$ activity, are needed to set insight into a possible target for the heat inactivation of cells. 본 연구는 열보호제 또는 열증감제의 존재하에서 세포 생존곡선, 단백질 합성률, DNA 중합효소 $\beta$의 활성변화를 비교 검토함으로써 SCK 종양세포가 열에 의해서 불활성화될 때의 표적이 무엇인지를 밝혀보기 위해서 수행되었다. 본 실험의 결과로 추정하건대 열에 의한 세포치사는 단백질 합성률의 변화와는 직접적인 연관성이 없으나, DNA 중합효소 $\beta$의 활성도와는 밀접한 연관성이 있음을 알 수 있다. 즉, 단백질의 분해 또는 비정상적인 단백질의 합성이 세포의 환경을 변화시키고 이것이 DNA 중합효소 $\beta$의 활성에 영향을 미침으로써 간접적으로 세포의 치사를 초래할 것으로 짐작할 수 있다. 따라서, 세포의 열불화성화의 표적을 좀더 분명히 밝히기 위해서는 세포의 환경변화와 DNA 중합효소 $\beta$의 활성과의 관계를 추구하는 연구가 수행되어야 할 것으로 사료된다.

• Communications for Statistical Applications and Methods
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• 제10권2호
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• pp.585-594
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• 2003

It has been generally recognized that conventional binomial or Poisson model provides poor fits to the actual correlated binary data due to the extra-binomial variation. A number of generalized statistical models have been proposed to account for this additional variation. Among them, beta-binomial, correlated-binomial, and modified-binomial models are binomial-related models which are frequently used in modeling the sum of n correlated binary data. In many situations, it is reasonable to assume that n correlated binary data are exchangeable, which is a special case of correlated binary data. The sum of n exchangeable correlated binary data is modeled relatively well when the above three binomial-related models are applied. But the estimation results of correlation coefficient turn to be quite different. Hence, it is important to identify which model provides better estimates of model parameters(success probability, correlation coefficient). For this purpose, a small-scale simulation study is performed to compare the behavior of above three models.

• BMB Reports
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• 제42권11호
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• pp.758-763
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• 2009

Cancer-associated antigen (CAGE) induces the expression of matrix metalloproteinase-2 (MMP-2) by activating Akt, which in turn interacts with inhibitory kappa kinase $\beta$ ($I{\kappa}K{\beta}$) to activate nuclear factor ${\kappa}B$ (NF-${\kappa}B$). Akt and p38 mitogen activated protein kinase (p38 MAPK) are necessary for CAGE-mediated induction of the AP-1 subunit JunB, whereas extracellular regulated kinase (ERK) is necessary for the induction of fos-related antigen-1 (Fra-1). Induction of MMP-2 by CAGE requires activator of protein-1 (AP-1) to be bound. Specific binding of JunB to MMP-2 promoter sequences was shown by chromatin immunoprecipitation (ChIP) analysis.

• Bulletin of the Korean Chemical Society
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• 제13권1호
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• pp.83-87
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• 1992

The ring expansion of 1,3-thiazolidines 4 derived from ${\beta}$-ketoacid derivatives to the corresponding dihydro-1,4-thiazines 1 by using the action of chlorine on 4 has been achieved. In the chlorinolysis unisolable sulfenyl chlorides 5 may be formed from chlorosulfonium ions 11 by ${\beta}$-elimination involving carbonyl activated methylene hydrogens. Addition of sulfenyl chloride to the internal double bond appears to form probable thiiranium ions 14, which in turn gave 1 with loss of acidic proton. Imminium ions 15 could be hydrolyzed easily to give enol 8. As a side reaction, dihydrothiazine that was formed was further chlorinated to produce dichlorides 16 which were rearranged readily to the chloromethyl compounds 10.

• Biomolecules & Therapeutics
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• 제26권6호
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• pp.560-567
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• 2018

In the present study, we tried to examine whether resveratrol regulates the expression of matrix metalloproteinases (MMPs) through affecting nuclear factor-kappa B ($NF-{\kappa}B$) in articular chondrocytes. Rabbit articular chondrocytes were cultured in a monolayer, and reverse transcription-polymerase chain reaction (RT-PCR) was used to measure interleukin-${\beta}$ ($IL-1{\beta}$)-induced gene expression of MMP-3, MMP-1, MMP-13, a disintegrin and metalloproteinase with thrombospondin motifs-4 (ADAMTS-4), ADAMTS-5 and type II collagen. Effect of resveratrol on $IL-1{\beta}$-induced secretion of MMP-3 was investigated in rabbit articular chondrocytes using western blot analysis. To elucidate the action mechanism of resveratrol, effect of resveratrol on $IL-1{\beta}$-induced $NF-{\kappa}B$ signaling pathway was investigated in SW1353, a human chondrosarcoma cell line, by western blot analysis. The results were as follows: (1) resveratrol inhibited the gene expression of MMP-3, MMP-1, MMP-13, ADAMTS-4, and ADAMTS-5, but increased the gene expression of type II collagen; (2) resveratrol reduced the secretion of MMP-3; (3) resveratrol inhibited $IL-1{\beta}$induced activation (phosphorylation) of inhibitory kappa B kinase (IKK), and thus phosphorylation and degradation of inhibitory kappa $B{\alpha}$ ($I{\kappa}B{\alpha}$); (4) resveratrol inhibited $IL-1{\beta}$-induced phosphorylation and nuclear translocation of $NF-{\kappa}B$ p65. This, in turn, led to the down-regulation of gene expression of MMPs in SW1353 cells. These results suggest that resveratrol can regulate the expression of MMPs through affecting $NF-{\kappa}B$ by directly acting on articular chondrocytes.

• Asian-Australasian Journal of Animal Sciences
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• 제11권3호
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• pp.293-299
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• 1998

This study was undertaken to measure the concentrations of estradiol-$17{\beta}$, progesterone and testosterone, and to study their relationship with each other and with follicular size in individual buffalo ovarian follicles categorized as small (4 to 5 mm diameter), medium (6 to 9 mm diameter) and large (${\geq}10mm$ diameter). Steroid hormone concentrations varied markedly within follicles of each size category. Estradiol-$17{\beta}$ concentrations (pmol/ml) were positively related to follicular diameter (R = 0.34, n = 308, p < 0.001) and were significantly higher (p < 0.001) in large (1$118.46{\pm}30.25$), compared to those in medium follicles ($50.32{\pm}8.29$) which, in turn were significantly higher (p < 0.001) than those in small follicles ($19.70{\pm}$5.57). Progesterone and testosterone concentrations (pmol/ml) were not related to follicular diameter and were not different among small ($330.99{\pm}27.32$ and $17.68{\pm}2.44$ respectively), medium ($384.84{\pm}26.20$ and $36.47{\pm}4.55$, respectively) and large follicles ($253.25{\pm}32.23$ and $22.57{\pm}4.48$, respectively). Estradiol-$17{\beta}$ and progesterone concentrations were positively related (R = 0.39, n = 47, p < 0.01) in small, unrelated in medium and negatively related in large follicles (R = -0.59, n = 23, p < 0.01). There was no relationship between estradiol-$17{\beta}$ and testosterone concentrations in follicles of all the three size categories. Progesterone and testosterone concentrations were positively related in large follicles (R = 0.57, n = 18, p < 0.02). There was no relationship between the two hormones in small and medium sized follicles. When the follicles with estradiol-$17{\beta}$/progesterone molar ratios of > 1.00 were considered non-atretic, and the rest at different stages of atresia, 197/208(95%) follicles were found to be atretic.

• Molecules and Cells
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• 제22권3호
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• pp.353-359
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• 2006

The bone morphogenetic protein (BMP) family has been implicated in control of cartilage development. Here, we demonstrate that BMP-2 promotes chondrogenesis by activating p38 mitogen-activated protein kinase (MAPK), which in turn downregulates $Wnt-7a/{\beta}$-catenin signaling responsible for proteasomal degradation of Sox9. Exposure of mesenchymal cells to BMP-2 resulted in upregulation of Sox9 protein and a concomitant decrease in the level of ${\beta}$-catenin protein and Wnt-7a signaling. In agreement with this, the interaction of Sox9 with ${\beta}$-catenin was inhibited in the presence of BMP-2. Inhibition of the p38 MAPK pathway using a dominant negative mutant led to sustained Wnt-7a signaling and decreased Sox9 expression, with consequent inhibition of precartilage condensation and chondrogenic differentiation. Moreover, overexpression of ${\beta}$-catenin caused degradation of Sox9 via the ubiquitin/26S proteasome pathway. Our results collectively indicate that the increase in Sox9 protein resulting from downregulation of ${\beta}$-catenin/Wnt-7a signaling is mediated by p38 MAPK during BMP-2 induced chondrogenesis in chick wing bud mesenchymal cells.

• 한국조리학회지
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• 제23권3호
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• pp.15-28
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• 2017

The purpose of this study is to examine the influence of workplace harassment in foodservice industry culinary staff's on organizational silence, counterproductive work behavior and turnover intent. Based on total 234 samples obtained from empirical research, this study tested the reliability and fitness of the research model and verified a total of 5 hypotheses using the AMOS program. Using a structural equation model (SEM), hypothesized relationships in the model were tested simultaneously. The proposed model provided an adequate fit the data, $x^2=75.936$ (p<.001), df=41, CMIN/DF=1.852, GFI=.946, AGFI=.913, NFI=.914, TLI=.944, CFI=.958, RMSEA=.060. The model's fit, as indicated by these indexes, was deemed satisfactory, thus providing a good basis for testing the hypothesized paths. The SEM showed that the relational workplace harassment (${\beta}=.957$) had a positive significant influence on organizational silence, organizational silence (${\beta}=.934$) had a positive significant influence on counterproductive work behavior. Also, counterproductive work behavior (${\beta}=.815$) had a positive significant influence on turnover intention. The moderating effects on gender and job status did not show significant effect. Limitations and future research directions are also discussed.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1988년도 추계학술대회 논문집
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• pp.67-70
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• 1988

In this paper, thermally stimulated currents (TSC) of corona-charged PTFE film were studied. Corona electrets which were formed by applying high voltages ${\pm}$5∼${\pm}$8[kV], to PTFE film of 100[$\mu\textrm{m}$] thickness, were experimented to measure TSC in the temperature range from -100[$^{\circ}C$] to 200[$^{\circ}C$]. As the result, four peaks of ${\gamma}$, ${\beta}$$_2$, ${\beta}$$_1$ and ${\alpha}$ were obtained at the temperature of -40[$^{\circ}C$], 30[$^{\circ}C$], 90[$^{\circ}C$] and 170[$^{\circ}C$], respectively. Speaking of the origins of these peaks, first of all, ${\gamma}$ peak is believed to show up by virtue of CF$_2$groups. B$_2$ peak seems to turn up by detrapping of the electrons which are accelerated by the corona exposure. ${\beta}$$_1$ peak looks to be ascribed to detrapping of the dipole and the trapped electron. Finally, ${\alpha}$ peak appears to result from detrapping of the electrons which are trapped in the para-crystalline region.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.330.2-330.2
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• 2002

The conformational study on cyclic Ac-Cys-Pro-Xaa-Cys-NHMe (Ac-CPXC-NHMe: X = Ala, Val. Leu. Aib. Gly. His. Phe, Tyr. Asn. and Ser) peptides has been carried out using the ECEPP/3 force field and the hydration shell model in the unhydrated and hydrated states. This work has been undertaken to investigate structural implications of the CPXC sequence as the chain reversal for the initiation of protein folding and as the motif for active site of disulfide oxidoreductases. The backbone conformation DAAA is in common the most feasible for cyclic CPXC peptides in the hydrated state. which has a type 1${\beta}$-turn at the Pro-Xaa sequence. The proline residue and the hydrogen bond between backbones of two cystines appear to play a role in stabilizing this preferred conformation of cycilc CPXC peptides. However. the distributions of backbone conformations and ${\beta}$-turns may indicate that the cyclic CPXC peptide seems to exist as an ensemble of ${\beta}$-turns and coiled conformations. The intirnsic stability of the cyclic CPXC motif itself the active conformation appears to play a role in determining electrochemical properties of disulfide oxidoreductases.