• KDI Journal of Economic Policy
• /
• 제32권4호
• /
• pp.75-114
• /
• 2010

본 연구는 우리나라에서 정보통신자본의 활용이 경제 전반의 생산성을 높이는데 기여하고 있는지를 1970~2005년 기간의 산업별 자료를 이용하여 분석하였다. 특히 정보통신자본의 축적과 생산성 향상 사이에 상당한 시차가 존재할 가능성을 고려하였다. 생산성 향상을 유발할 수 있을 만큼 정보통신자본이 충분히 축적되었는지를 평가하기 위해 선진국과 비교한 결과, 경제 전체로서는 선진국과의 격차를 줄이고 있으나, 이는 주로 정보통신자본의 집적도가 높은 산업의 비중이 증가한 데 기인하며, 개별 산업에서는 선진국에 비해 낮은 수준이 지속되고 있는 것으로 나타났다. 한편, 산업별 성장회계 결과는 정보통신 고이용부문의 총요소생산성 증가세가 2000년 이후 개선되었으나, 사업서비스 등 일부 산업을 제외하면 정보통신자본의 축적이 생산성 향상을 초래하였을 가능성은 높지 않은 것으로 나타났다. 회귀분석 결과는 정보통신 생산부문을 제외하면 정보통신자본의 축적이 생산성 향상으로 이어지기까지 상당한 시간이 소요되고 있을 가능성을 시사하였다. 따라서 정보통신기술의 생산성 파급효과를 강화하기 위해서는 정보통신자본의 축적을 저해하는 제도적 요인을 점검하는 한편, 정보통신기술 활용을 위한 보완적 혁신이 용이하게 이루어질 수 있도록 제도적 환경을 개선하는 것이 중요하다고 생각된다.

• Asian Pacific Journal of Cancer Prevention
• /
• 제14권8호
• /
• pp.4853-4858
• /
• 2013

Objectives: To investigate whether hypoxia has an effect on regulation of multidrug resistance (MDR) to chemotherapeutic drugs in laryngeal carcinoma cells and explore the role of hypoxia-inducible factor-$1{\alpha}$ (HIF-$1{\alpha}$). Methods: Laryngeal cancer cells were cultured under normoxic and hypoxic conditions. The sensitivity of the cells to multiple drugs and levels of apoptosis induced by paclitaxel were determined by MTT assay and annexin-V/propidium iodide staining analysis, respectively. HIF-$1{\alpha}$ expression was blocked by RNA interference. The expression of HIF-$1{\alpha}$ gene was detected by real-time quantitative RT-PCR and Western blotting. The value of fluorescence intensity of intracellular adriamycin accumulation and retention in cells was evaluated by flow cytometry. Results: The sensitivity to multiple chemotherapy agents and induction of apoptosis by paclitaxel could be reduced by hypoxia (P<0.05). A the same time, the adriamycin releasing index of cells was increased (P<0.05). However, resistance acquisition subject to hypoxia in vitro was suppressed by down-regulating HIF-$1{\alpha}$ expression. Conclusion: HIF-$1{\alpha}$ could be considered as a key regulator for mediating hypoxia-induced MDR in laryngeal cancer cells via inhibition of drug-induced apoptosis and decrease in intracellular drug accumulation.

• 대한의생명과학회지
• /
• 제22권1호
• /
• pp.1-8
• /
• 2016

Several studies have investigated the various effects of dexamethasone (Dex) on the proliferation and differentiation of mesenchymal stem cells (MSCs). Previously, we reported that co-treatment with L-ascorbic acid 2-phosphate and fibroblast growth factor (FGF)-2 maintained differentiation potential in MSCs through expression of hepatocyte growth factor (HGF). In this study, we investigated the effects of co-treatment with FGF-2 and Dex on the proliferation and differentiation potential of MSCs during a 2-month culture period. Co-treatment with FGF-2 and Dex increased approximately a 4.7-fold higher accumulation rate of MSC numbers than that by FGF-2 single treatment during a 2-month culture period. Interestingly, co-treatment with FGF-2 and Dex increased expression of HGF and maintained adipogenic differentiation potential during this culture period. These results suggest that co-treatment with FGF-2 and Dex preserves the proliferation and differentiation potential during long-term culture.

• Biomolecules & Therapeutics
• /
• 제23권1호
• /
• pp.90-97
• /
• 2015

Water chestnut (Trapa japonica Flerov.) is an annual aquatic plant. In the present study, we showed that the treatment of water chestnut extracted with boiling water resulted in a significant increase 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity and decrease the intracellular $H_2O_2$-induced accumulation of reactive oxygen species. In addition, water chestnut extract (WCE) inhibited lipopolysaccharide (LPS)-induced nitric oxide production and suppressed mRNA and protein expression of the inducible nitric oxide synthase gene. The cytokine array results showed that WCE inhibited inflammatory cytokine secretion. Also, WCE reduced tumor necrosis factor-${\alpha}$- and interleukin-6-induced nuclear factor-${\kappa}B$ activity. Furthermore, during sodium lauryl sulfate (SLS)-induced irritation of human skin, WCE reduced SLS-induced skin erythema and improved barrier regeneration. These results indicate that WCE may be a promising topical anti-inflammatory agent.

• Journal of Ginseng Research
• /
• 제39권3호
• /
• pp.199-205
• /
• 2015

Background: Ginsenoside Rb1 (G-Rb1), the major active constituent of ginseng, improves insulin sensitivity and exerts antidiabetic effects. We tested whether the insulin-sensitizing and antidiabetic effects of G-Rb1 results from a reduction in ectopic fat accumulation, mediated by inhibition of lipolysis in adipocytes. Methods: Obese and diabetic db/db mice were treated with daily doses of 20 mg/kg G-Rb1 for 14 days. Hepatic fat accumulation was evaluated by measuring liver weight and triglyceride content. Levels of blood glucose and serum insulin were used to evaluate insulin sensitivity in db/db mice. Lipolysis in adipocytes was evaluated by measuring plasma-free fatty acids and glycerol release from 3T3-L1 adipocytes treated with G-Rb1. The expression of relevant genes was analyzed by western blotting, quantitative real-time polymerase chain reaction, and enzyme-linked immunosorbent assay kit. Results: G-Rb1 increased insulin sensitivity and alleviated hepatic fat accumulation in obese diabetic db/db mice, and these effects were accompanied by reduced liver weight and hepatic triglyceride content. Furthermore, G-Rb1 lowered the levels of free fatty acids in obese mice, which may contribute to a decline in hepatic lipid accumulation. Corresponding to these results, G-Rb1 significantly suppressed lipolysis in 3T3-L1 adipocytes and upregulated the perilipin expression in both 3T3-L1 adipocytes and mouse epididymal fat pads. Moreover, G-Rb1 increased the level of adiponectin and reduced that of tumor necrosis factor-${\alpha}$ in obese mice, and these effects were confirmed in 3T3-L1 adipocytes. Conclusion: G-Rb1 may improve insulin sensitivity in obese and diabetic db/db mice by reducing hepatic fat accumulation and suppressing adipocyte lipolysis; these effects may be mediated via the upregulation of perilipin expression in adipocytes.

• 약학회지
• /
• 제55권6호
• /
• pp.478-484
• /
• 2011

Non-alcoholic fatty liver disease is known to be frequently associated with obesity and type 2 diabetes. We examined the effects of EtOH extracts from Triticum aestivum on lipid accumulation during the differentiation of 3T3-L1 preadipocytes to screening the candidate materials in preventing non-alcoholic fatty liver disease. The lipid level in adipocytes was determined by Oil Red O staining. The treatment of 50% ethanol, but not water and 100% ethanol extracts, from Triticum aestivum at concentration of 0.5 $mg/ml$ inhibited lipid accumulation in 3T3-L1 cells, revealing no cell toxicity. Thus, the fractions of $CH_2Cl_2$, EtOAc and BuOH were separated from 50% EtOH extract to characterize anti-adipogenic effect. The $CH_2Cl_2$ fraction at concentration of $50{\mu}g/ml$ effectively inhibited the lipid accumulation in the adipocytes compared to those of EtOAc and BuOH at concentration of $50{\mu}g/ml$. The intracellular triglyceride accumulation also was significantly reduced by treatment of $CH_2Cl_2$ fraction in concentration-dependent manner. Western blot analysis showed that the $CH_2Cl_2$ fraction attenuated the intracelluar level of fatty acid synthase(FAS) accompanied by attenuated expression of Peroxidase proliferator-activated receptor ${\gamma}$ ($PPAR{\gamma}$) adipogenic transcription factor. These results suggest that $CH_2Cl_2$ fraction from 50% EtOH extract of Triticum aestivum may has the potent anti-adipogenic effects by inhibiting the transactivation of $PPAR{\gamma}$.

• Journal of Microbiology and Biotechnology
• /
• 제17권6호
• /
• pp.1024-1030
• /
• 2007

We investigated the human apolipoprotein E2 (apoE2) transgenic mouse as an animal model system for age-related macular degeneration (AMD). Transgenic mice expressing human apoE2 and C57BL/6J mice were fed normal chow or a high-fat diet for 4 weeks. Eyes were collected from the mice and lipid deposits in retinal pigment epithelium (RPE) were assessed using electron microscopy. The expressions of apoE, vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), and pigment-epithelium derived factor (PEDF), which are molecular markers for angiogenesis, were assessed with immunohistochemistry. Eyes from apoE2 mice, regardless of diet, contained lipid accumulation in RPE under electron microscopy, whereas control C57BL/6J eyes did not. Lipid accumulation was found predominantly in the RPE and the Bruch's membrane and increased in the eyes of apoE2 mice after one month of a high-fat diet ($8{\pm}2\;per\;50{\mu}m^2$ for normal chow and $11{\pm}2\;per\;50\;{\mu}m^2,\;p<0.05)$. ApoE expression was similar in the apoE2 and control mice; however, VEGF and bFGF were overexpressed in the retinal pigment epithelium of apoE2 eyes compared with control eyes, and PEDF expression was slightly decreased. These expression patterns of VEGF, bFGF, and PEDF suggest angiogenesis is progressing in apoE2 eyes. In conclusion, the eyes of apoE2 mice develop typical lipid accumulations, a common characteristic of AMD, making them a suitable animal model for AMD. The expression profile of VEGF and bFGF on the retinal pigment epithelium suggests that apoE2 may induce neovascularization by altering angiogenic cytokines.

• 한국작물학회:학술대회논문집
• /
• 한국작물학회 2017년도 9th Asian Crop Science Association conference
• /
• pp.159-159
• /
• 2017

Drought, a common environmental constraint, induces a range of physiological, biochemical and molecular changes in plants, and can cause severe reductions in crop yield. Consequently, understanding the molecular mechanisms of drought tolerance is an important step towards crop biotechnology. Here, we report that the rice (Oryza sativa) homeodomain-leucine zipper class IV transcription factor gene, ${\underline{R}ice}$ ${\underline{o}utermost}$ ${\underline{c}ell-specific}$ gene 10 (Roc10), enhances drought tolerance and grain yield by increasing lignin accumulation in ground tissues. Overexpression of Roc10 in rice significantly increased drought tolerance at the vegetative stages of growth and promoted both more effective photosynthesis and a reduction in water loss rate, compared with non-transgenic controls or RNAi transgenic plants. Importantly, Roc10 overexpressing plants had a higher drought tolerance at the reproductive stage of growth and a higher grain yield compared with the controls under field-drought conditions. Roc10 is mainly expressed in outer cell layers including the epidermis and the vasculature of the shoots, which coincides with areas of cell wall lignification. Roc10 overexpression elevated the expression levels of lignin biosynthetic genes in shoots, with a concomitant increase in the accumulation of lignin, while the overexpression and RNAi lines showed opposite patterns of lignin accumulation. We identified downstream target genes of Roc10 by performing RNA-seq and chromatin immunoprecipitation (ChIP)-seq analyses of shoot tissues. Roc10 was found to directly bind to the promoter of PEROXIDASEN/PEROXIDASE38, a key gene in lignin biosynthesis. Together, our findings suggest that Roc10 confers drought stress tolerance by promoting lignin biosynthesis in ground tissues.

• Journal of Veterinary Science
• /
• 제23권5호
• /
• pp.74.1-74.16
• /
• 2022

Background: Previous studies have presented evidence to support the significant association between red meat intake and colon cancer, suggesting that heme iron plays a key role in colon carcinogenesis. Epigallocatechin-3-gallate (EGCG), the major constituent of green tea, exhibits anti-oxidative and anti-cancer effects. However, the effect of EGCG on red meat-associated colon carcinogenesis is not well understood. Objectives: We aimed to investigate the regulatory effects of hemin and EGCG on colon carcinogenesis and the underlying mechanism of action. Methods: Hemin and EGCG were treated in Caco2 cells to perform the water-soluble tetrazolium salt-1 assay, lactate dehydrogenase release assay, reactive oxygen species (ROS) detection assay, real-time quantitative polymerase chain reaction and western blot. We investigated the regulatory effects of hemin and EGCG on an azoxymethane (AOM) and dextran sodium sulfate (DSS)-induced colon carcinogenesis mouse model. Results: In Caco2 cells, hemin increased cell proliferation and the expression of cell cycle regulatory proteins, and ROS levels. EGCG suppressed hemin-induced cell proliferation and cell cycle regulatory protein expression as well as mitochondrial ROS accumulation. Hemin increased nuclear factor erythroid-2-related factor 2 (Nrf2) expression, but decreased Keap1 expression. EGCG enhanced hemin-induced Nrf2 and antioxidant gene expression. Nrf2 inhibitor reversed EGCG reduced cell proliferation and cell cycle regulatory protein expression. In AOM/DSS mice, hemin treatment induced hyperplastic changes in colon tissues, inhibited by EGCG supplementation. EGCG reduced the hemin-induced numbers of total aberrant crypts and malondialdehyde concentration in the AOM/DSS model. Conclusions: We demonstrated that EGCG reduced hemin-induced proliferation and colon carcinogenesis through Nrf2-inhibited mitochondrial ROS accumulation.

• 한국디지털건축인테리어학회논문집
• /
• 제12권3호
• /
• pp.39-47
• /
• 2012

General concern over 'Quality of Life(QOL)' has caused many researches, which compare nations' or cities' QOL by the normative criteria proposed by themselves. The fact that these are characterized by subjectiveness makes this study have a purpose of trying to enhance the intersubjectiveness by means of quantitive analysis to find the factors on the QOL. This study uses statistical methods such as multiple regression and factor analysis based on the secondary data from the "2011 Seoul Survey". The survey includes many items, for example happiness index and satisfaction for work, amenity, etc.. And the analysis tells three findings as follows; Firstly, five subcategories of happiness have relative importance in the order of (1)financial condition, (2)health, (3)social activities, (4)community relationship and (5)family life. These generally constitute the first factor extracted by factor analysis and named 'abundance-family-intimacy factor.' Secondly, the 'abundance-family-intimacy factor' and the 'information-danger factor' among five factors(the others are 'learning-giving factor', 'local patriotism-hope for rise factor' and 'amenity-comfort factor') have statistically significant effect to QOL. Thirdly, the first factor has positive effect, but the second has negative to QOL. Note is needed to the fact that the items on SNS and internet belong to second factor and to the result that these make QOL deteriorate. These results should be considered as having limited meaning of statistical aspect. But accumulation of following studies by quantitive approach is anticipate to make more practical and general meaning.