• Journal of Microbiology and Biotechnology
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• 제8권3호
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• pp.197-202
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• 1998

Aliphatic alkenals having 6 to 13 carbons were evaluated for antifungal activity against Saccharomyces cerevisiae. The activity was gradually increased with chain length, e.g., (E)-2-decenal and (E)-2-undecenal exhibited maximum potency, while (E)-2-dodecenal and (E)-2-tridecenal were completely inactive. Alkenals showed increasing inhibitory activity with chain length, as in the case of antifungal activity, towards glucose-induced medium acidification by the plasma membrane $H^+$-ATPase of S. cerevisiae. The group including (E)-2-nonenal, (E)-2-decenal, and (E)-2-undecenal exhibited maximum potency, but the potency of (E)-2-dodecenal and (E)-2-tridecenal demonstrated a sudden drop with respect to the former group. (E)-2-Nonenal revealed dose-responsive inhibition to the medium acidification and inhibited over 90% at a concentration of 1.25 mM ($175.3{\mu}g$/ml). In contrast to (E)-2-undecenal whose inhibitory efficiency increased with incubation time, inhibition by (E)-2-dodecenal was reversed with time. Of the tested alkenals, (E)-2-heptenal and (E)-2-octenal most highly inhibited ATP hydrolytic activity by the plasma membrane $H^+$ ATPase, while (E)-2-heptenal at 10 mM ($1121.8{\mu}g$/ml) showed an inhibitory efficacy of 93.2%.

• 산경연구논집
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• 제15권5호
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• pp.1-15
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• 2024

Purpose: The purpose of this study is to explore the development and characteristics of e-commerce in China and analyze the current status of e-commerce platforms in China. Research design, data and methodology: To explore the development of e- commerce in China, this study collects and analyzes Chinese journals and secondary sources. It also conducts a case analysis of the success strategies of leading Chinese e-commerce companies. Results: The analysis showed that China's e-commerce is active in various forms of e-commerce, including B2B, B2C, and C2C, and that the development of e-commerce in China has been divided into three main stages. The Chinese government has been actively implementing various policies to promote the development of e-commerce. Conclusions: In this context, this paper specifically examines the development process of e- commerce in China, the current status of the Chinese e-commerce market, and the characteristics of the Chinese e-commerce market. In addition, the paper analyzes representative B2B, B2C, and C2C companies in China's e-commerce market. The results of the analysis show that Huichongwang, a B2B company, Jingdong, a B2C company, and Taobao, a C2C company, have achieved rapid growth through their core strategies and capabilities. The study also analyzed in detail the problems faced by the Chinese government and companies.

• 한국미생물·생명공학회지
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• 제16권2호
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• pp.111-118
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• 1988

유기산 생산균인 L. casei Y, Str. faecium C, Str. faecalis, Cl. butyricum M, B. toyoi를 사료첨가제와 발효유로부터 분리 확인하여 이들 균주가 자돈의 대장균증 설사를 유발시키는 E. coli $A_2$, E. coli G$_7$에 대하여 in vitro에서는 어떤 항균효과를 나타내는지 조사한 결과를 요약하면 다음과 같다. 1. L. casei Y, Str. faecium C, Str. faecalis, B. toyoi Cl. butyricum M을 각각 배양한 BL broth 3일 배양액은 모두 E. coli $A_2$와 E. coli G$_7$에 대하여 항균효과를 나타내었고, 이들 배양액을 E. coli $A_2$와 E. coli G$_7$에 대한 발육 Disc 확산시험 결과 그 저지환 직경은 각각 15mm와 17mm, 14mm와 15mm, 13mm와 14mm, 11mm와 13 mm, 10mm와 12mm 였다. 2. 유기산 생산 능력이 우수한 균일수록 E. coli $A_2$와 E. coli G$_7$에 대한 항균력이 높게 관찰되었으며, L. casei Y와 Str. faecium C가 이들 두 대장균에 대하여 높은 항균력을 나타내었다. 3. 유기산 생성균과 대장균(E. coli $A_2$, E. coli G$_7$)을 BL broth 에 혼합 배양할 때 E. coli $A_2$와 E. coli G$_7$은 배양액의 pH가 5.0 이하일 때 생육억제 되었고, pH 4.5 이하였을 때 사멸되었다. 4. 생성된 유기산은 배양액의 pH를 저하시킴과 동시에 항균성 물질로 직접 작용하여 E. coli $A_2$와 E. coli G$_7$의 생육저해 또는 사멸을 유도하였다. 5. E. coli $A_2$가 E. coli G$_7$보다 유기산 생산균의 대사산물에 대하여 더 높은 내성을 갖고 있었다.

• Journal of Microbiology and Biotechnology
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• 제24권2호
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• pp.287-294
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• 2014

The transcription factor E2F1 is active during G1 to S transition and is involved in the cell cycle and progression. A recent study reported that increased E2F1 is associated with DNA damage and tumor development in several tissues using transgenic models. Here, we show that E2F1 expression is regulated by tristetraprolin (TTP) in prostate cancer. Overexpression of TTP decreased the stability of E2F1 mRNA and the expression level of E2F1. In contrast, inhibition of TTP using siRNA increased the E2F1 expression. E2F1 mRNA contains three AREs within the 3'UTR, and TTP destabilized a luciferase mRNA that contained the E2F1 mRNA 3'UTR. Analyses of point mutants of the E2F1 mRNA 3'UTR demonstrated that ARE2 was mostly responsible for the TTP-mediated destabilization of E2F1 mRNA. RNA EMSA revealed that TTP binds directly to the E2F1 mRNA 3'UTR of ARE2. Moreover, treatment with siRNA against TTP increased the proliferation of PC3 human prostate cancer cells. Taken together, these results demonstrate that E2F1 mRNA is a physiological target of TTP and suggests that TTP controls proliferation as well as migration and invasion through the regulation of E2F1 mRNA stability.

• Journal of Nutrition and Health
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• 제32권3호
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• pp.213-220
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• 1999

The purpose of this study was to determine the dose effects of taurine supplementation and effects of taurine depletion in diabetic rats. Sprague-Dawley male rats were fed the purified diets and supplemented with 1, 2 or 3% taurine in drinking water for 7 weeks(E1, E2 and E3, respectively). To induce taurine depletion, rats were treated with 5% $\beta$-alanine in drinkeng water (EA). Diabetes was induced by streptozotocin injection(50mg/kg B.W) after 3 weeks. Taurine-depleted diabetic rats(EA)had significantly lower body weight compared to those of nondiabetic(CO), nontaurine-supplemented diabetic(E0) and taurine-supplemented diabetic rats(E1, E2 and E3). E0 had significantly higher food intake compared to that of CO and EA. E1, E2 and E3, however, had significantly lower food intake compared to that of E0, and E3 had significantly lower food intake compared to that of E1 and E2. E0 had significantly higher water intake compare to that of CO and EA. EI had significantly lower water intake compared to that of E0. Blood glucose concentration of E0 was significantly increased compared to that of CO and EA. E2 and E3 had significantly lower blood glucose concentration compared to E0 and E1. Also there was a dose effect in blood glucose concentration between E2 and E3. The total cholesterol and LDL-cholesterol concentrations of EA were significantly increased compared to those of other groups. Therefore, it may be suggested that taurine supplementation is necessary for diabetes in order to prevent diabetic complications such as cardiac vascular diseases.

• 통상정보연구
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• 제5권1호
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• pp.39-59
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• 2003

The purpose of this paper is to examine the possibility of whether B2B e-marketplaces continue to grow. There are numerous barriers to the growth of e-marketplace, but certain key factors can push e-marketplaces beyond these obstacles. In the stage of generating traffic, it is essential to find a vertical area to attract buyers and sellers which can generate B2B transaction through e-marketplace. Generating traffic is possible only for e-marketplaces established by those who have vertical knowledges and strong off-line relationship in the vertical areas. In the stage of concentrating traffic, more attention should be given to reach critical mass and to increase transaction through e-marketplace. Currently, there seems to be a tendency that having major buyers as members of a e-marketplace is an true factor for the successful e-marketplace. Finally, to attain the locking traffic, e-marketplace needs to have the ability to generate revenue through B2B transaction. What we have learn from this study is that having the software-technology is not a sufficient condition to successfully operate B2B e-marketplace. It is important for e-marketplace to attract major players in order to increase B2B transaction, and also to make profit by them.

• 한국디지털정책학회:학술대회논문집
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• 한국디지털정책학회 2005년도 춘계학술대회
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• pp.145-175
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• 2005

In 2001, e-Credit guarantee system was introduced by the Korea Credit Guarantee Fund(KCGF) to extends the credit guarantee services for the purchasing amount on credit in the B2B e-Marketplace. It combines both the merits of bill of exchange and credit card and eliminates the uneasiness related to the unpaid accounts due to the non-facial e-Marketplace. The purpose of this paper is to empirically analyze both the causal relationship and influences among theoretical variables by the structural equation model(SEM). e-Credit guarantee system can be a good strategy for promoting B2R e-Marketplace. The level of application of e-Credit guarantee system is attributable to both the characteristics of B2B e-Marketplace and products. The cost reduction or saving in purchasing procedures, production and stockpiling will be possible through e-Credit guarantee system. The close linkage of financial institutions with the enterprises based on e-Credit guarantee system will further promote B2B e-Marketplace in Korea.

• 디지털융복합연구
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• 제3권1호
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• pp.45-73
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• 2005

In 2001, e-Credit guarantee system was introduced by the Korea Credit Guarantee Fund(KCGF) to extends the credit guarantee services for the purchasing amount on credit in the B2B e-Marketplace. It combines both the merits of bill of exchange and credit card and eliminates the uneasiness related to the unpaid accounts due to the non-facial e - Marketplace. The purpose of this paper is to empirically analyze both the causal relationship and influences among theoretical variables by the structural equation model(SEM). e-Credit guarantee system can be a good strategy for promoting B2B e-Marketplace. The level of application of e-Credit guarantee system is attributable to both the characteristics of B2B e-Marketplace and products. The cost reduction or saving in purchasing procedures, production and stockpiling will be possible through e-Credit guarantee system. The close linkage of financial institutions with the enterprises based on e-Credit guarantee system will further promote B2B e-Marketplace in Korea.

• The Korean Journal of Physiology and Pharmacology
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• 제14권6호
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• pp.391-397
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• 2010

E2F transcription factors and their target genes have been known to play an important role in cell growth control. We found that curcumin, a polyphenolic phytochemical isolated from the plant Curcuma longa, markedly suppressed E2F4 expression in HCT116 colon cancer cells. Hydrogen peroxide was also found to decrease E2F4 protein level, indicating the involvement of reactive oxygen species (ROS) in curucmin-induced downregulation of E2F4 expression. Involvement of ROS in E2F4 downregulation in response to curcumin was confirmed by the result that pretreatment of cells with N-acetylcystein (NAC) before exposure of curcumin almost completely blocked the reduction of E2F4 expression at the protein as well as mRNA level. Anti-proliferative effect of curcumin was also suppressed by NAC which is consistent to previous reports showing curcumin-superoxide production and induction of poly (ADP-ribose) polymerase (PARP) cleavage as well as apoptosis. Expression of several genes, cyclin A, p21, and p27, which has been shown to be regulated in E2F4-dependent manner and involved in the cell cycle progression was also affected by curcumin. Moreover, decreased (cyclin A) and increased (p21 and p27) expression of these E2F4 downstream genes by curcumin was restored by pretreatment of cells with NAC and E2F4 overexpression which is induced by doxycycline. In addition, E2F4 overexpression was observed to partially ameliorate curcumin-induced growth inhibition by cell viability assay. Taken together, we found curcumin-induced ROS down-regulation of E2F4 expression and modulation of E2F4 target genes which finally lead to the apoptotic cell death in HCT116 colon cancer cells, suggesting that E2F4 appears to be a novel determinant of curcumin-induced cytotoxicity.

• Genomics & Informatics
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• 제7권4호
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• pp.187-194
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• 2009

Cytochrome P450 2E1 (CYP2E1) is a member of the cytochrome P450 superfamily, and it is a key enzyme responsible for the metabolic activation of many smallmolecular-weight compounds such as alcohol, which is classified as a human carcinogen. In this study, we identified 19 single nucleotide polymorphisms (SNPs) in CYP2E1 in Korean population. In these SNPs, we examined possible genetic association of CYP2E1 polymorphisms with HBV clearance and the risk of hepatocellular carcinoma (HCC). Five common polymorphic sites were selected, CYP2E1 polymorphisms at rs381-3867, rs3813870, rs2070673, rs2515641 and rs2480257, considering their allele frequencies, haplotype-tagging status and LDs for genotyping in larger-scale subjects (n=1,092). Statistical analysis demonstrated that CYP2E1 polymorphisms and haplotypes show no significant association with HBV clearance, HCC occurrence and onset age of HCC (p>0.05). Previous studies, however, have shown contradictory findings on associations of CYP2E1 polymorphisms with CYP2E1 activities and HCC risk. Comparing the contrasting results of previous researches suggest that CYP2E1 polymorphism is associated with CYP2E1 activity induced by ethanol, but is not directly associated with HCC risk. CYP2E1 variation/haploype information identified in this study will provide valuable information for future studies on CYP2E1.