• The Korean Journal of Pharmacology
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• v.21 no.1
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• pp.12-26
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• 1985

The generation of $O^{-}_{2}{\cdot}$ and its toxic effects were studied with rat brain mitochondria. The production of $O^{-}_{2}{\cdot}$ from mitochondria in the presence of succinate and antimycin was demonstrated by SOD-inhibitable reduction of NBT. Although succinate can support the $O^{-}_{2}{\cdot}$ formation, the highest rate needs antimycin indicating that blockade of electron flow in the respiratory chain augments the univalent reduction of molecular oxygen. Under this condition, $H_2O_2$ was also observed to be produced. But its formation appears to be derived from the dismutation of the primary product, $O^{-}_{2}{\cdot}$ since the rate of $H_2O_2$ production was markedly decreased by NBT and ferricytochrome c. The $O^{-}_{2}{\cdot}$ and $H_2O_2$ produced were able to cause toxic actions to mitochondrial and extra-mitochondrial components as shown by lipid peroxidation of mitochondrial membrane, and inactivation and lysis of isocitrate dehydrogenase and erythrocytes added to the medium, respectively. In all the toxic actions observed, $Fe^{++}$ was required. It appears that in the toxic actions $OH{\cdot}$ generated from the iron-catalyzed Haber-Weiss reaction acts as a mediator. This was supported by the finding that mitochondria in the presence of succinate and antimycin produced ethylene from methional, and $Fe^{++}$ added increased the ethylene production. The observed toxic actions of mitochondrial $O^{-}_{2}{\cdot}$ may provide evidence supporting a potential role of mitochondria as a source of oxygen radicals to cause tissue damage.

• Korean Journal of Food Science and Technology
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• v.49 no.1
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• pp.28-34
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• 2017

Biocatalytic modification of natural resources can be used to generate novel compounds with specific properties, such as higher viscosity and reactivity. The production of hydroxy fatty acids (HFAs), originally found in low quantities in plants, is a good example of the biocatalytic modification of natural vegetable oils. HFAs show high potential for application in a wide range of industrial products, including resins, waxes, nylons, plastics, lubricants, cosmetics, and additives in coatings and paintings. In a recent study, Pseudomonas aeruginosa strain PR3 was used to produce 7,10-dihydroxy-8(E)-octadecenoic acid (DOD) from oleic acid. This present study focused primarily on the utilization of three natural nut oils obtained from the Philippines -pili nut oil (PNO), palm oil (PO), and virgin coconut oil (VCO)- to produce DOD by P. aeruginosa strain PR3. Strain PR3 produced DOD from PNO and PO only, with PNO being the more efficient substrate. An optimization study to achieve the maximum DOD yield from PNO revealed the optimal incubation time and medium pH to be 48 h and 8.0, respectively. Among the carbon sources tested, fructose was the most efficiently used, with a maximum DOD production of 130 mg/50 mL culture. Urea was the optimal nitrogen source, with a maximum product yield of 165 mg/50 mL culture. The results from this study demonstrated that PNO could be used as an efficient substrate for DOD production by microbial bioconversion.

• Korean Journal of Food Science and Technology
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• v.50 no.5
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• pp.543-548
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• 2018

The current study examined antioxidant and neuronal cell protective effects of the crude polysaccharide fraction in Cudrania tricuspidata fruits (CTP). The radical scavenging activities of (1,1-diphenyl-picrylhydrazyl and 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid)) and reducing power and FRAP of CTP were increased dose-dependently. In addition, the expression of neuroprotective effect of CTP was tested in HT22 mouse hippocampal cells. CTP treatment exhibited non cytotoxicity at dose levels below $500{\mu}g/mL$. Within this optimal concentration range, CTP treatment significantly increased cell viability in $H_2O_2-treated$ HT22 cells. Furthermore, CTP treatment increased superoxide dismutase (SOD) activity and decreased malonaldehyde (MDA) levels in HT22 cells. Therefore, these results indicate that the crude polysaccharide fraction from Cudrania tricuspidata fruits (CTP) possesses antioxidant activities and displays therapeutic potential as a useful source material in the development of brain disorder treatments targeting oxidative stress in neuronal cells.

• Atmosphere
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• v.23 no.1
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• pp.93-102
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• 2013

Atmospheric transport pathway of an air mass is an important constraint controlling the chemical properties of the air mass observed at a designated location. Such information could be utilized for understanding observed temporal variabilities in atmospheric concentrations of long-lived chemical compounds, of which sinks and/or sources are related particularly with natural and/or anthropogenic processes in the surface, and as well as for performing inversions to constrain the fluxes of such compounds. The Lagrangian particle dispersion model FLEXPART provides a useful tool for estimating detailed particle dispersion during atmospheric transport, a significant improvement over traditional "single-line" trajectory models that have been widely used. However, those without a modeling background seeking to create simple back-trajectory maps may find it challenging to optimize FLEXPART for their needs. In this study, we explain how to set up, operate, and optimize FLEXPART for back-trajectory analysis, and also provide automatization programs based on the open-source R language. Discussions include setting up an "AVAILABLE" file (directory of input meteorological fields stored on the computer), creating C-shell scripts for initiating FLEXPART runs and storing the output in directories designated by date, as wells as processing the FLEXPART output to create figures for a back-trajectory "footprint" (potential emission sensitivity within the boundary layer). Step by step instructions are explained for an example case of calculating back trajectories derived for Anmyeon-do, Korea for January 2011. One application is also demonstrated in interpreting observed variabilities in atmospheric $CO_2$ concentration at Anmyeon-do during this period. Back-trajectory modeling information introduced in this study should facilitate the creation and automation of most common back-trajectory calculation needs in atmospheric research.

• Clinical and Experimental Pediatrics
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• v.48 no.8
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• pp.894-900
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• 2005

Purpose : Because of the unavailability of marrow transplantation, umbilical cord blood (CB) is increasingly being used. We evaluated the potential of ex vivo expansion and clonality in CD34+ cells separated from cord blood source and mobilized peripheral blood (PB) in a serum-free media. Methods : The CD34+ cells, selected from CB and mobilized PB, were expanded with hematopoietic growth factors. They were then cultured for burst-forming units of erythrocytes (BFU-E), colony-forming units of granulocytes and monocytes (CFU-GM) and colony-forming units of megakaryocytes (CFU-Mk) at culture days 0, day 4, day 7, and day 14 with various growth factors. Results : The CB-selected CD34+ cells showed significantly higher total cell expansion than those from the PB at day 7 (2 fold increase than PB). The CB-selected CD34+ cells produced more BFU-E colonies than did the PB on culture at days 7 and at day 14. Also, the CB-selected CD34+ cells produced more CFU-Mk colonies than did the PB on culture at day 4 and at day 7. Conclusion : The ex vivo expansion of the CB cells may be promising in producing total cellular expansion, CFU-Mk and BFU-E compared with PB for 7 to 14 days. The growth factors combination including megakaryocyte growth and development, flt3-ligand and interleukin-3 showed more expansion in the view of total cells and clonal maintenance compared with less combination.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.10
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• pp.1359-1366
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• 2000

An experiment was carried out to study plasma levels of hormones and metabolites of crossbred Holstein cattle during late pregnancy (28 days pre partum), early lactation (30 days post partum), mid-lactation (120 days post partum) and late lactation (210 days post partum). Two breed types of Holstein $Friesian{\times}Red$ Sindhi (50:50 = 50%HF) and Holstein $Friesian{\times}Red$ Sindhi (87.5:12.5 = 87.5%HF) were divided into four groups of four animals each. Two groups of each breed were fed with either rice straw treated with 5% urea or pangola hay (Digitaria decumbens) as the source of roughage throughout the experiments. There were a substantial increases in the mean levels of total triiodothyronine ($T_3$), insulin and glucagon at the onset of lactation, and maintained in a high levels during lactation advance for all groups of experiments. The mean levels of prolactin and thyroxine ($T_4$) were not significantly different among groups of animals, but the plasma cortisol concentration was slightly higher in both groups of 50%HF in comparison with those of 87.5%HF animals. The mean levels of plasma growth hormone (GH) of both groups of 87.5%HF animals feeding on either hay or urea treated rice straw markedly rose in the early period of lactation and markedly reduced in mid- and late lactation. These changes were accompanied with changes of milk yield. In contrast to 50%HF animals, plasma GH levels were considerably higher in the late pregnant period than in the early period of lactation and it remained constant as its value at the early lactation throughout the experimental period. The high levels of both plasma progesterone and estradiol concentration significantly declined after parturition and remained low through lactating period. The plasma glucose level in the 50%HF animals feeding on either hay or urea treated rice straw was higher than the 87.5%HF animals in all periods of experiments. Changes in plasma FFA levels of both types of crossbred animals were depended on the endocrine status during late pregnancy and lactation. The levels of plasma FFA of 50%HF animals were significantly higher (p<0.05) than those of 87.5%HF animals during late pregnancy. Both plasma ${\beta}$-hydroxybutyrate and lactate concentrations were not affected by feeding on either hay or urea treated rice straw during late pregnancy and lactation. These data demonstrate that there were no differences in the physiological performances in the same crossbred animals fed either hay or urea treated rice straw. The 87.5%HF animal has the genetic potential for a high milk yield and homeorhetic adaptation for mammary function differed from 50%HF animals during periods of lactation. Altering lactation persistency in 87.5%HF is regulated mainly by chronically acting growth hormones through the period of lactation.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.5
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• pp.661-671
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• 2006

Steers (n = 335) of known genetic backgrounds from four fundamentally different growth types were subjected to two production systems to study the main effects and possible interactive effects on carcass composition. Growth types were animals with genetic potential for large mature weight (LL), intermediate mature weight-late maturing (IL), intermediate mature weight-early maturing (IE), and small mature weight-early maturing (SE). Each year, in a nine year study, calves of each growth type were weaned and five steers of each growth type were developed on pasture or feedlot and harvested at approximately 20 and 14 mo of age, respectively. Data recorded were chilled carcass weight and percentages of forequarter, foreshank, chuck, rib, plate, brisket, hindquarter, round, rump, shortloin, sirloin, flank, lean, fat, bone, and retail cuts. The growth $type{\times}production$ system interaction was an important source of variation in chilled carcass weight (p = 0.0395) and percentage retail cuts (p = 0.001), lean (p = 0.001), fat (p = 0.001), rump (p = 0.0454), shortloin (p = 0.0487), and flank (p = 0.001). The ranking of the growth $type{\times}production$ system means for percentage lean was LL-pasture>IL-pasture = IE-pasture = SE-pasture>LL-feedlot, IL-feedlot>IE-feedlot = SE-feedlot. The growth $type{\times}production$ system interaction was non-significant (p>0.05) for forequarter, foreshank, chuck, rib, plate, brisket, hindquarter, round and bone. Growth types of IE and SE yielded greater (p<0.05) mean forequarter than did growth types of IL and LL ($51.6{\pm}0.3$ and $51.5{\pm}0.3$ vs. $51.1{\pm}0.3$ and $50.8{\pm}0.3%$). Mean bone was highest (p<0.05) for the LL growth type and lowest (p<0.05) for the SE growth type ($19.5{\pm}0.5$ vs. $16.8{\pm}0.5%$). Mean bone was greater (p<0.05) for the pastured steers than for the feedlot steers ($21.8{\pm}0.8$ vs. $14.5{\pm}0.6%$). These data indicate that growth type responded differently in the two production systems and that these results should be helpful in the match of genetics to production resources.

• Journal of Microbiology and Biotechnology
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• v.17 no.10
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• pp.1700-1703
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• 2007

Microorganisms capable of degrading crude oil were isolated and grown in soybean oil as a sole carbon source. The microbial cultures were used to control green peach aphids in vitro. Approximately 60% mortality of aphids was observed when the cultures were applied alone onto aphids. To examine the cultures as a pesticide formulation mixture, the cultures were combined with a low dose of the insecticide imidacloprid (one-fourth dose of recommended field-application rate) and applied onto aphids. The cultures enhanced significantly the insecticidal effectiveness of imidacloprid, which was higher than imidacloprid alone applied at the low dose. The isolated microorganisms exhibited high emulsifying index values and decreased surface tension values after being grown in soybean oil media. GC/MS analyses showed that microorganisms degraded soybean oil to fatty acids. The cultures were suggested to play the roles of wetting, spreading, and sticking agents to improve the effectiveness of imidacloprid. This is the first report on the control of aphids by using oil-degrading microbial cultures.

• Journal of Microbiology and Biotechnology
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• v.17 no.3
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• pp.496-510
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• 2007

This paper describes the use of a discrete mathematical model to represent the basic mechanisms of regulation of the bacteria E. coli in batch fermentation. The specific phenomena studied were the changes in metabolism and genetic regulation when the bacteria use three different carbon substrates (glucose, glycerol, and acetate). The model correctly predicts the behavior of E. coli vis-a-vis substrate mixtures. In a mixture of glucose, glycerol, and acetate, it prefers glucose, then glycerol, and finally acetate. The model included 67 nodes; 28 were genes, 20 enzymes, and 19 regulators/biochemical compounds. The model represents both the genetic regulation and metabolic networks in an integrated form, which is how they function biologically. This is one of the first attempts to include both of these networks in one model. Previously, discrete mathematical models were used only to describe genetic regulation networks. The study of the network dynamics generated 8 $(2^3)$ fixed points, one for each nutrient configuration (substrate mixture) in the medium. The fixed points of the discrete model reflect the phenotypes described. Gene expression and the patterns of the metabolic fluxes generated are described accurately. The activation of the gene regulation network depends basically on the presence of glucose and glycerol. The model predicts the behavior when mixed carbon sources are utilized as well as when there is no carbon source present. Fictitious jokers (Joker1, Joker2, and Repressor SdhC) had to be created to control 12 genes whose regulation mechanism is unknown, since glycerol and glucose do not act directly on the genes. The approach presented in this paper is particularly useful to investigate potential unknown gene regulation mechanisms; such a novel approach can also be used to describe other gene regulation situations such as the comparison between non-recombinant and recombinant yeast strain, producing recombinant proteins, presently under investigation in our group.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.4
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• pp.431-437
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• 2005

In this study, the profiles of the bacterial regrowth of indigenous bacteria in tap water and Pseudomonas fluorescence P17 were investigated for cases when carbon (glucose), and/or nitrogen ($NO_3^-$-N), and/or phosphorus ($PO_4^{3-}$-P) were added below sufficient nutrient concentration (SNC) and when carbon sources (glucose and acetate) and nitrogen sources ($NH_4^+$-N and $NO_3^-$-N) were added together. The bacterial regrowth was decreased with limitation of nutrients, and were lowered relatively in the sample, which plural nutrients were limited. In addition, phosphate might be the effective nutrient to control the bacterial regrowth in drinking water because the bacterial regrowth was significantly decreased by the limitation of phosphate. In contrast, the bacterial regrowth was retarded with increasing the concentration of $NO_3^-$-N. For simultaneously adding carbon(glucose or acetate) and nitrogen sources ($NH_4^+$-N and $NO_3^-$-N), the regrowth counts appeared highly in the condition, for both glucose and acetate. And, the regrowth was increased with increasing $NH_4^+$-N concentration as a nitrogen source.