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Transcript accumulation of carotenoid biosynthesis genes in the cyanobacterium Synechocystis sp. PCC 6803 during the dark-to-light transition is mediated by photosynthetic electron transport

  • Ryu, Jee-Youn;Song, Ji-Young;Chung, Young-Ho;Park, Young-Mok;Chow, Wah-Soon;Park, Youn-Il
    • Plant Biotechnology Reports
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    • v.4 no.2
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    • pp.149-155
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    • 2010
  • Expression of the genes for carotenoid bio-synthesis (crt) is dependent on light, but little is known about the underlying mechanism of light sensing and signalling in the cyanobacterium Synechocystis sp. PCC 6803 (hereafter, Synechocystis). In the present study, we investigated the light-induced increase in the transcript levels of Synechocystis crt genes, including phytoene synthase (crtB), phytoene desaturase (crtP), ${\zeta}$-carotene desaturase (crtQ), and ${\beta}$-carotene hydroxylase (crtR), during a darkto-light transition period. During the dark-to-light shift, the increase in the crt transcript levels was not affected by mutations in cyanobacterial photoreceptors, such as phytochromes (cph1, cph2 and cph3) and a cryptochrome-type photoreceptor (ccry), or respiratory electron transport components NDH and Cyd/CtaI. However, treatment with photosynthetic electron transport inhibitors significantly diminished the accumulation of crt gene transcripts. Therefore, the light induction of the Synechocystis crt gene expression is most likely mediated by photosynthetic electron transport rather than by cyanobacterial photoreceptors during the dark-to-light transition.

Nuclear Receptor PPARα Agonist Wy-14,643 Ameliorates Hepatic Cell Death in Hepatic IKKβ-Deficient Mice

  • Kim, Taehyeong;Wahyudi, Lilik Duwi;Gonzalez, Frank J.;Kim, Jung-Hwan
    • Biomolecules & Therapeutics
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    • v.25 no.5
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    • pp.504-510
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    • 2017
  • Inhibitor of nuclear factor kappa-B kinase beta ($IKK{\beta}$) plays a critical role in cell proliferation and inflammation in various cells by activating $NF-{\kappa}B$ signaling. However, the interrelationship between peroxisome proliferator-activated receptor ${\alpha}$ ($PPAR{\alpha}$) and $IKK{\beta}$ in cell proliferation is not clear. In this study, we investigated the possible role of $PPAR{\alpha}$ in the hepatic cell death in the absence of $IKK{\beta}$ gene using liver-specific Ikkb-null ($Ikkb^{F/F-AlbCre}$) mice. To examine the function of $PPAR{\alpha}$ activation in hepatic cell death, wild-type ($Ikkb^{F/F}$) and $Ikkb^{F/F-AlbCre}$ mice were treated with $PPAR{\alpha}$ agonist Wy-14,643 (0.1% w/w chow diet) for two weeks. As a result of Wy-14,643 treatment, apoptotic markers including caspase-3 cleavage, poly (ADP-ribose) polymerase (PARP) cleavage and TUNEL-positive staining were significantly decreased in the $Ikkb^{F/F-AlbCre}$ mice. Surprisingly, Wy-14,643 increased the phosphorylation of p65 and STAT3 in both Ikkb and $Ikkb^{F/F-AlbCre}$ mice. Furthermore, BrdU-positive cells were significantly increased in both groups after treatment with Wy-14,643. Our results suggested that $IKK{\beta}-derived$ hepatic apoptosis could be altered by $PPAR{\alpha}$ activation in conjunction with activation of $NF-{\kappa}B$ and STAT3 signaling.

Insertional mutations exhibiting high cell-culture density HCD phenotypes are enriched through continuous subcultures in Chlamydomonas reinhardtii

  • Thung, Leena;He, Jing;Zhu, Qingling;Xu, Zhenyu;Liu, Jianhua;Chow, Yvonne
    • ALGAE
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    • v.33 no.1
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    • pp.127-141
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    • 2018
  • Low efficiency in microalgal biomass production was largely attributed to the low density of algal cell cultures. Though mutations that reduced the level of chlorophyll or pigment content increased efficiency of photon usage and thus the cell-culture density under high-illumination growth conditions (e.g., >$500{\mu}mol\;photon\;m^{-2}\;s^{-1}$), it was unclear whether algae could increase cell-culture density under low-illumination conditions (e.g., ${\sim}50{\mu}mol\;photon\;m^{-2}\;s^{-1}$). To address this question, we performed forward genetic screening in Chlamydomonas reinhardtii. A pool of >1,000 insertional mutants was constructed and subjected to continuous subcultures in shaking flasks under low-illumination conditions. Complexity of restriction fragment length polymorphism (RFLP) pattern in cultures indicated the degree of heterogeneity of mutant populations. We showed that the levels of RFLP complexity decreased when cycles of subculture increased, suggesting that cultures were gradually populated by high cell-culture density (HCD) strains. Analysis of the 3 isolated HCD mutants after 30 cycles of subcultures confirmed that their maximal biomass production was 50-100% higher than that of wild type under low-illumination. Furthermore, levels of chlorophyll content in HCD mutant strains were similar to that of wild type. Inverse polymerase chain reaction analysis identified the locus of insertion in two of three HCD strains. Molecular and transcriptomic analyses suggested that two HCD mutants were a result of the gain-of-function phenotype, both linking to the abnormality of mitochondrial functions. Taken together, our results demonstrate that HCD strains can be obtained through continuous subcultures under low illumination conditions.

Estimating USLE Soil Erosion through GIS-based Decision Support System

  • Her, Y.G.;Kang, M.S.;Park, S.W.
    • Journal of The Korean Society of Agricultural Engineers
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    • v.48 no.7
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    • pp.3-14
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    • 2006
  • The objective of this study was to develop a GIS-based decision support system (GIS-USLE system) to estimate soil erosion and evaluate its effect on concentrated upland plots in Godang district, Korea. This system was developed for the ArcView environment using A VENUE script. Three modules were used in the GIS-USLE system, namely pre-processing, the USLE factors calculator module, and post-processing. This system benefits from a user friendly environment that allows users with limited computer knowledge to use it. This system was applied to 1,285 individual upland plots ranging from 0.005 to 1.347 ha in size with an average slope steepness of 14 %. The rainfall distributions were estimated using the three methods, namely Mononobe and Yen-Chow with Triangle and with Trapezoid type, and then used to calculate the rainfall erosivity factor. The soil erosion amounts from the 1,285 individual plots in the study area by 2 year return period with a 24h maximum rainfall amount of 154.6 mm were estimated at 5 tons/ha on average. Slope appeared to be the most important factor affecting soil erosion estimation, as expected. The prototype model was applied to the project area, and the results appeared to support the practical applications. By examining many fields simultaneously, this system can easily provide fast estimation of soil erosion and thus reveal the spatial pattern of erosion from fields in a region. This study will help estimate and evaluate soil erosion in concentrated upland districts and identify the best management practices.

Effects of Vitamin E and Dehydroepiandrosterone on the Formation of Preneoplastic Lesions in Rat Hepatocellular Carcinogenesis (비타민 E와 Dehydroepiandrosterone이 화학적 발암원으로 유도한 쥐간의 전암성 병변에 미치는 영향)

  • Kim, Sook-Hee;Choi, Hay-Mie
    • Journal of Nutrition and Health
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    • v.38 no.5
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    • pp.364-372
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    • 2005
  • This study is designed to examine the effects of dietary supplementation with vitamin E and dehydroepiandrosterone (DHEA) on the formation of preneoplastic lesions in diethylnitrosamine (DEN) induced rat hepatocarcinogenesis. All Weaning male Sprague-Dawley rats were initiated by a single dose of DEN (200mg/kg body weight), subjected to two­thirds partial hepatectomy 3 weeks later and were sacrificed 8 weeks after DEN initiation. Two weeks after initiation, rats were fed Purina purified rodent diet 5053 (Ralston Purina Rat chow, USA) with $1.5\%$ (15,000 IU/kg diet) vitamin E, $0.5\%$ DHEA and both of those supplemented diet for 6 weeks. Placental glutathione S-transferase (GST-P) positive foci, the activities of catalase, total-glutathione peroxidase (GPx) , glutathione reductase (GR), glutathione S-transferase (GST) and thiobarbituric acid reactive substances (TBARS) contents were decreased significantly by vitaimin E supplement. On the other hand GST-P positive foci number, Cu/Zn-superoxide dismutase (SOD) and glucose 6-phosphatase (G6Pase) activities weren't changed by vitamin E supplement. It might suggest that protective effect of vitamin E against hepatocarcinogens is not involved in the formation of the GST-P positive foci but related to the expansion of that. It seemed that vitamin E supplement helped endogenous defense system in carcinogenesis by decreasing TBARS contents, $H_2O_2$, organic peroxides. Therefore, vitamin E seemed to protect cell from free radical damage in carcinogenesis. By DHEA supplement liver weight and liver/body ratio were increased, the area and number of GST-P positive foci, the activities of catalase, GR, total GPx, GST and the TBARS contents were decreased significantly. On the other hand Cu/Zn-SOD and G6Pase activities weren't changed by DHEA supplement. In hepatocarcinogenesis the activities of antioxidant enzymes weren't increased by DHEA supplement. DHEA did not increase the oxidative stress, while DHEA seems to have anticarcinogenic effect in rats hepatocarcinogenesis.

Effect of Zingiber Officinale Roscoe Extracts on Mice Immune Cell Activation (생강 추출물 투여가 마우스 면역세포 활성에 미치는 영향)

  • 류혜숙;김현숙
    • Journal of Nutrition and Health
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    • v.37 no.1
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    • pp.23-30
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    • 2004
  • Ginger (Zingiber officinale Roscoe) has been used as a raw material in many traditional preparations since the ancient time. As a component of traditional health products, Ginger is known to be effective as appetite enhancer, anticold and anti-inflammation. This study was performed to investigate the immunomodulative effects of Ginger in mouse, using in vitro and ex vivo experiments. In vitro experiment, the mice splenocytes proliferation and three kinds of cytokines (IL-1 $\beta$, IL-6, and TNF-$\alpha$) prodution by peritoneal macrophages cultured with ethanol and water extracts of Ginger were used to indicate the immunomodulative effect. In order to elucidate the immunomodulative effects of Ginger ex vivo, water extract of Ginger was orally administrated into mice, and isolated splencytes and macrophages were used as experimental model. Ex vivo experiment, six to seven week old mice were fed ad libitum on a chow diet, and water extract of finger was orally administrated every other day for four weeks at two different concentractions (50 and 500 mg/kg B.W./day). In vitro study, the splenocytes proliferation was increased when water extract was supplemented in the range of 50-500 $\mu$l/ml concentration. In case of cytokines production, IL-1 $\beta$, IL-6 and TNF-$\alpha$ released by activated peritoneal macrophages were augmented by the supplementation of water extract of the Ginger. Ex vivo experiment, the highest proliferation of splenocytes and production of cytokines by activated peritoneal macrophages were seen in the mice orally administrated at the concentration of 500 mg/kg B.W./day. In conclusion, this study suggests that Ginger extracts may enhance the immune function by regulating the splenocytes proliferation and enhancing the cytokine prodution capacity by activated macrophages in mice.

Anticancer activity of subfractions containing pure compounds of Chaga mushroom (Inonotus obliquus) extract in human cancer cells and in Balbc/c mice bearing Sarcoma-180 cells

  • Chung, Mi-Ja;Chung, Cha-Kwon;Jeong, Yoon-Hwa;Ham, Seung-Shi
    • Nutrition Research and Practice
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    • v.4 no.3
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    • pp.177-182
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    • 2010
  • The Chaga mushroom (Inonotus obliquus) has been used in folk medicine to treat cancers. However, limited information exists on the underlying anticancer effects of the major component of I. obliquus in vivo. We hypothesize that the pure compounds ($3{\beta}$-hydroxy-lanosta-8,24-dien-21-al, inotodiol and lanosterol, respectively) separated from I. obliquus would inhibit tumor growth in Balbc/c mice bearing Sarcoma-180 cells (S-180) in vivo and growth of human carcinoma cells in vitro. To test this hypothesis, the growth inhibition of each subfraction isolated from I. obliquus on human carcinoma cell lines (lung carcinoma A-549 cells, stomach adenocarcinoma AGS cells, breast adenocarcinoma MCF-7 cells, and cervical adenocarcinoma HeLa cells) was tested in vitro. Then, after S-180 implantation, the mice were fed a normal chow supplemented with 0, 0.1 or 0.2 mg of subfraction 1, 2 or 3 per mouse per day. All of the subfractions isolated from I. obliquus showed significant cytotoxic activity against the selected cancer cell lines in vitro. Subfraction 1 was more active than subfraction 2 and subfraction 3 against the A549, AGS and MCF-7 cancer cell lines in vitro. In in vivo results, subfraction 1 isolated from I. obliquus at concentrations of 0.1 and 0.2 mg/mouse per day significantly decreased tumor volume by 23.96% and 33.71%, respectively, as compared with the control. Subfractions 2 and 3 also significantly inhibited tumor growth in mice bearing S-180 as compared with the control mouse tumor. Subfraction 1 isolated from I. obliquus showed greater inhibition of tumor growth than subfractions 2 and 3, which agrees well with the in vitro results. The results suggest that I. obliquus and its compounds in these subfractions isolated from I. obliquus could be used as natural anticancer ingredients in the food and/or pharmaceutical industry.

Rainfall-Runoff Analysis by Calculation of the Time Distribution Models for Storms (降雨의 時間 分布模型 算定에 의한 降雨-流出 解析)

  • 민경형;이영대
    • Water for future
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    • v.29 no.6
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    • pp.189-201
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    • 1996
  • The main objective of this study is to determine the time distribution models of rainfall in Korea for estimating design floods and to suggest new runoff model(Geomorphologic Instantaneous Unit Hydrograph; GIUH) in order to be easily use the rainfall-runoff model put rainfall models practice to be suitable for the regional characteristics of hydrologic situation by practicing engineers. As a result, the reappearance of triangular hyetograph and GIUH runoff model showed promising. The historical data from about 13,000 event-rainfalls and 73 rainfall-runoff measuring data during 12 years in International Hydrological Program (IHP) basins have been used to determine the statistical factors of the time distribution for rainfalls by the Yen-Chow, Huff, Pilgrim-Cordery and Mononobe models. The Rational, Kajiyama, Nakayasu and Clark model and GIUH model that this study runoff model were used for the purpose of application limit for basin area against design concept by the estimation of flood runoff and the derivation of empirical equations to estimate the parameters for ungaged basins.

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The Influence of Long-term Aloe Supplement on Anti-oxidative Defenses and Cholesterol Content in Brain and Kidney of Aged Rats

  • Lim, Beong-Ou;Park, Pyo-Jam;Park, Dong-Ki;Choi, Wahn-Soo;Kim, Jong-Dai;Yu, Byung-Pal
    • Korean Journal of Medicinal Crop Science
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    • v.15 no.5
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    • pp.352-356
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    • 2007
  • The present study was investigated the anti-oxidative effects of aloe vera ingestion on brain and kidney in aged rats by monitoring several oxidative-related parameters. Male specific pathogen-free Fischer 344 rats were randomly divided into four groups of five rat each: Group A was fed test chow without aloe supplementation; Group B was fed a diet containing a 1% freeze-dried aloe filet; Group C was fed a diet containing a 1% charcoal-processed, freeze-dried aloe filet; and Group D was fed a diet containing a charcoal-processed, freeze-dried, whole leaf aloe in drinking water. Analyses of tissues were done at 4 months and 16 months of age. Results showed that a long-term intake of aloe, regardless of the preparation used, enhanced antioxidant defenses against lipid peroxidation, as indicated by reduced phosphatidylcholine hydroperoxide levels in both brain and kidney. The additional benefit of aloe intake on the anti-oxidative action was evidenced by enhanced superoxide dismutase and catalase activity in all aloe-ingested groups. Another beneficial effect of aloe shown in this study, although not an anti-oxidative parameter, was its cholesterol-lowering effect as detected in brain and kidney with significant decreases at age16 months of aloe-fed rats. Based on these findings, we conclude that a long-term dietary aloe supplementation modulated the anti-oxidative defense systems and cholesterol level.

Impact of Copper Densities of Substrate Layers on the Warpage of IC Packages

  • Gu, SeonMo;Ahn, Billy;Chae, MyoungSu;Chow, Seng Guan;Kim, Gwang;Ouyang, Eric
    • Journal of the Microelectronics and Packaging Society
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    • v.20 no.4
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    • pp.59-63
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    • 2013
  • In this paper, the impact of the copper densities of substrate layers on IC package warpage is studied experimentally and numerically. The substrate strips used in this study contained two metal layers, with the metal densities and patterns of these two layers varied to determine their impacts. Eight legs of substrate strips were prepared. Leg 1 to leg 5 were prepared with a HD (high density) type of strip and leg 6 to leg 8 were prepared with UHD (ultra high density) type of strip. The top copper metal layer was designed to feature meshed patterns and the bottom copper layer was designed to feature circular patterns. In order to consider the process factors, the warpage of the substrate bottom was measured step by step with the following manufacturing process: (a) bare substrate, (b) die attach, (c) applying mold compound (d) and post reflow. Furthermore, after the post reflow step, the substrate strips were diced to obtain unit packages and the warpage of the unit packages was measured to check the warpage trends and differences. The experimental results showed that the warpage trend is related to the copper densities. In addition to the experiments, a Finite Element Modeling (FEM) was used to simulate the warpage. The nonlinear material properties of mold compound, die attach, solder mask, and substrate core were included in the simulation. Through experiment and simulation, some observations were concluded.