• Archives of Pharmacal Research
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• v.20 no.5
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• pp.465-470
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• 1997

The human cDNA clone UDPGTh2, encoding a liver UDP-glucuronosyltransferase (UDPGT), was isolated from a .gamma.gt 11 cDNA library by hybridization to mouse transferase cDNA clone, UDPGTm1. The two clones had 74% nlicleotide sequence identities in the coding region. UDPGTh2 encoded a 529 amino acid protein with an amino terminus membrane-insertion signal peptide and a carboxyl terminus membrane-spanning region. In order to establish substrate specificity, the clone was inserted into the pSVL vector (pUDPGTh2) and expressed in COS 1 cells. Sixty potential substrates were tested using cells transfected with pUDPGTh2. The order of relative substrate activity was as follows: 4-hydroxyestrone > estriol >2-hydroxyestriol > 4-hydroxyestradiol > $6{\alpha}$-hydroxyestradiol >$5{\alpha}$-androstane-$3{\alpha}$, $11{\beta}$, $17{\beta}$-triol=5${\beta}$-androstane-$3{\alpha}$ ${\beta}$, $17{\beta}$-triol. There were only trace amounts of gulcuronidation of 2-hydroxyestradiol and 2-hydroxyestrone, and in contrast to other cloned transferase, no gulcuronidation of either the primary estrogens and androgens (estrone, $17{\beta}$estradiol/testosterone, androsterone) or any of the exogenous substrates tested was detected. A lineweaver-Burk plot of the effect of 4-hydroxystrone concentration on the velocity of glucuronidation showed an apparent Km of $13{\mu}M$. The unique specificity of this transferase might play an important role in regulating the level and activity of these potent and active estrogen metabolites.

• Archives of Pharmacal Research
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• v.20 no.5
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• pp.454-458
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• 1997

Two human liver UDP-glucuronosyltransferase cDNA clones, HLUG25 and UDPGTh2 were previously shown to encode isozymes active in the glucuronidation of hyodeoxycholic acid (HDCA) and certain estrogen derivatives (e.g., estriol and 3,4-catechol estrogens), respectively. in this study we have found that the UDPGTh2-encoded isoform (UDPGTh2) and HLUG25-encoded isoform (UDPGThl) have parallel aglycone specificities. When expressed in COS 1 cells, each isoform metabolized three types of dihydroxy- or trihydroxy-substituted ring structures, including the 3,4-catechol estrogen (4-hydroxyestrone), estriol, 17-epiestriol, and HDCA, but the UDPGTh2 isozyme was 100-fold more efficient than UDPGTh1. UDPGTh1 and UDPGTh2 were 86% identical overall (76 differences out of 528 amino acids), including 55 differences in the first 300 amino acids of the amino terminus, a domain which conferred the substrate specificity. The data indicated that a high level of conservation in the amino terminus was not required for the preservation of substrate selectivity. Analysis of glucuronidation activity encoded by UDPGTh1/UDPGTh2 chimeric cDNA constructed at their common restriction sites, Sac I (codon 297), Nco I (codon 385), and Hha I (codon 469), showed that nine amino acids between residues 385 and 469 were important for catalytic efficiency, suggesting that this region represented a domain which was critical for the catalysis but distinct from that responsible for aglycone-selection. These data indicate that UDPGTh2 is a primary isoform responsible for the detoxification of the bile salt intermediate as well as the active estrogen intermediates.

• Korean Journal of Environmental Biology
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• v.33 no.1
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• pp.7-18
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• 2015

In this study, we studied the effect of dissolved cement powder on Carassius auratus by analysis of the morphophysiological changes. The gill exposed to dissolved cement powder showed the thickened primary lamellae and the activity of chloride cells and mucous cells was also significantly increased and the proliferation, separation and clubbing of gill filament was observed in the secondary lamellae. In the kidney tissue, the space in Bowman's capsule was widen and the arrangement of dermis was irregular due to the thinned epidermis in the integument tissue. The activities of antioxidant enzymes and LDH tended to increase with the duration of cement exposure. It was confirmed that the up-regulated proteins were identified as involved in glycolysis and energy metabolism and down-regulated proteins were myofibrillar proteins which were involved in muscle contraction by the cement exposure to the integument. With these results, dissolved cement powder was thought to be a big threat to the survival of the fish because it causes the morphological changes and weakens the physiological activity in C. auratus tissues.

• Journal of Life Science
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• v.12 no.6
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• pp.786-795
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• 2002

Three-day-old sunfower(Helianthus annuus L.) seedlings were do-rooted and incubated in the nutrient solutions that contained either deficient or sufficient boron supply, and exposure to various pH and temperatures. In the absence of boron, no adventitious roots were formed in the majority of the seedlings. Boron caused the development of numerous adventitious roots in the lower part of the hypocotyl. The low pH damage was ameliorated by the simultaneous application of calcium, implying the involvement of calcium-requiring process in overcoming proton toxicity. Borate showed a strong ameliorative effect with $Ca^{2+}$. These results suggest that the primary target of proton toxicity may be linked to a disturbance of the stability in the pectic polysaccharide network, where calcium plays a key role in plant roots. Maximum temperature for the growth of adventitious roots was $25^{\circ}C$. Although cessation of growth is the most apparent symptom of boron deficiency, exogenous ascorbate improved adventitious root growth in plants in the absence of boron. From the results it is suggested that the inhibition of adventitious root resulting from boron deficiency, low pH and temperature damage may be a consequence of disrupted ascorbate metabolism.

• Korean Journal of Weed Science
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• v.4 no.1
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• pp.96-106
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• 1984

Changes in weed floras and development of plant resistance to herbicides seemed to be closely related with increased and repeated use of herbicides. Herbicide use increased from 5% of the total consumption of pesticide in 1950 to 45% in 1976 in world basis. About 200 herbicides have been introduced to agriculture so as to control about 206 weed species which have been recorded important to human beings. In Korea, there was about 351 times in increased use of herbicides from 1966 to 1982. Interspecific selection by herbicide is mainly responsible for changes in weed floras and resulted in varying tolerance or susceptibility to herbicides, together with the changes of agricultural practices. The present trend toward continuous cereal cultivation throughout world will lead to type of changes in weed floras favorable to therophyte which can survive under unfavorable conditions as seeds rather than the types of geophyte which can survive unfavorable seasons as buds placed below soil surface. However, geophyte such as Sagitaria pygmaea, and Scirpus jurtcoides, and Cyperus rotundus and Cynodon dactylon in temperate warm climate become severe paddy weeds, presumably because of the removal of annual weeds by herbicides. Since differential tolerance to 2,4-D was firstly reported in Agrostis stolofera, about 30 species of weeds in 18 genera are presently known to have developed resistance to triazine herbicides. Resistance of weed biotypes to triazine herbicide is not mainly due to limited absorption and translocation or to the difference in metabolism, but is the result of biochemical changes at the site of metabolic activity, such as a loss of herbicide affinity for triazine binding site in the photosystem II complex of the chloroplast membrane. Genetical study showed that plastid resistance to triazine was wholly inherited through cytoplasmic DNA in the case of Brassica campestris. Plant tissue culture method can be utilized as an alternate mean of herbicide screening and development of resistance variants to herbicides as suggested by Chaleff and Parsons. In this purpose, one should be certain that the primary target process is operational in cell culture. Further, there are a variety of obstacles in doing this type of research, particularly development of resistance source and it's regeneration because cultured cells and whole plants represent different developmental state.

• The Korean Journal of Nuclear Medicine
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• v.37 no.5
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• pp.325-330
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• 2003

Purpose: We describe a 54-year-old woman with systemic lupus erythematosus (SLE) who suddenly presented with chorea and had positive antiphospholipid antibodies. F-18 FDG PET showed abnormally increased glucose metabolism in bilateral putamen and primary motor cotex. Tc-99m ECD SPECT also showed abnormally increased regional cerebral blood flow in bilateral putamen. She was treated with corticosteroid and aspirin after which the symptoms improved. Four months later, follow up F-18 FDG PET showed improvement with resolution of hypermetabolism in bilateral putamen. This case suggests that striatal hypermetabolism is associated with chorea in SLE.

• The Korean Journal of Food And Nutrition
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• v.15 no.4
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• pp.307-313
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• 2002

The primary objective of these studies was to screen the materials showing inhibitions of HMG-CoA reductase in vitro. The secondary objective was to determine the effect of garlic, lovastatin and copper on cholesterol concentrations in plasma, liver and breast tissues in pullets. The degree of inhibition of the selective samples on HMG-CoA reductase activity was determined in vitro. The inhibition ratios of water soluble garlic extracts, lovastatin (methanol extracts) and copper to HMG-CoA reductase activity were 51.3%, 87.5%, and 82.0%, respectively. Control diet (basal diet) and experimental diets, garlic powder (3% in diet), lovastatin (300mg/Kg of diet) and copper (200mg/Kg of diet) were fed to pullets in order to investigate the changes of cholesterol concentration in plasma and tissues. Total cholesterol, HDL- and LDL-cholesterol in blood plasma were significantly reduced in pullets fed diet containing 3% garlic powder. However, copper significantly increased total cholesterol compared to control and lovastatin did not affect plasma cholesterol concentration. Total cholesterol and triglyceride of liver and breast tissues in pullets were not affected by adding the cholesterol-lowering materials to diets. The data suggests that it is not easy for HMG-CoA reductase inhibitors to reduce cholesterol levels in body due to complication of cholesterol metabolism. However, garlic administration can lower the levels of plasma cholesterol in pullets.

• Korean Journal of Clinical Pharmacy
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• v.20 no.2
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• pp.128-137
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• 2010

This review summarizes gender differences in pharmacokinetics, pharmacodynamics, and adverse drug reactions. Gender differences in pharmacokinetics are categorized by four major factors: absorption/bioavailability, distribution, metabolism, and elimination. There are sex-based differences in gastric emptying time, gastric alcohol dehydrogenase activity, apparent volume of distribution, ${\alpha}1$-acid glycoprotein level, phase I (CYP) and phase II metabolizing enzymes, glomerular filtration rate, and drug transporters. This review also reports gender differences in pharmacokinetics and pharmacodynamics of cardiovascular agents, central nervous system acting agents and antiviral agents. In addition, it has been reported that females experience more adverse reactions such as coughing, tachycardia, nausea, vomiting, rash, hypersensitivity, hepatotoxicity, and metabolic disorder after taking cardiovascular, central nervous system acting and antiviral agents. Therefore, in order to provide optimal drug dosage regimens both in male and female, gender differences in pharmacokinetics, pharmacodynamics, and adverse drug reactions must be considered.

• The Korean Journal of Ecology
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• v.16 no.3
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• pp.261-273
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• 1993

The nitrogen assimilation rate of nitrogenous nutrients by reservior phytoplankton was masured in the in situ condition in the euphotic layer of Lakes Soyang, Chuncheon and Uiam located on the upper reaches of the North Han River System in August, 1983, Korea. The assimilation rate of ammonia, nitrate and urea nitrogen in surface water was 13, 2 and $13{\mu}g$ at. $N{\cdot}m^{-3}{\cdot}(12:10~18:15)^{-1}$ in Lake Soyang, 325, 27 and $59{\mu}g$ at. $N{\cdot}m^{-3}{\cdot}(12:30~18:30)^{-1}$ in Lake Chuncheon, and 174, 12 and $45{\mu}g$ at. $N{\cdot}m^{-3}{\cdot}(12:30~19:30)^{-1}$ in Lake Uiam. Ammonia and urea were perferntially utilized by reservoir phytoplankton. The dark/light ratios of nitrate assimilation were much lower than those of ammonia and urea assimilation of nitrate showed little contribution. The primary productuin was estimated as 59mg $C{\cdot}m^{-2}{\cdot}day^{-1}$ and 6.9mg $N{\cdot}m^{-2}{\cdot}day^{-1}$ in Lake Spyang, 217mg C{\cdot}m^{-2}{\cdot}day^{-1}$ and 26mg N{\cdot}m^{-2}{\cdot}day^{-1}$ in Lake Chuncheon, and 110mg C{\cdot}m^{-2}{\cdot}day^{-1}$ and 13mg N{\cdot}m^{-2}{\cdot}day^{-1}$ in Lake Uiam, with production ratios of 8.6, 8.4 and 8,4, respectively. The turnover time o ammonia and urea in the upper euphotic layer was 2 to 47 days and 4 to 38 days, respectively. Nitrate required much longer periods. In the euphotic layer of reservoirs, ammonia and urea played signigicant roles in the biogeoKDICical nitrogen metabolism.

• Journal of Microbiology and Biotechnology
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• v.16 no.8
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• pp.1311-1315
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• 2006

Aminocyclitol antibiotic validamycin A, a prime control agent for sheath blight disease of rice plants, is biosynthesized by Streptomyces hygroscopicus var. limoneus. Within the validamycin biosynthetic gene cluster, vldBC forms an operon of vldABC with vidA, the gene encoding 2-epi-5-epi-valiolone synthase. Biochemical studies, employing the recombinant proteins from Escherichia coli, established VldB and VldC as D-glucose $\alpha$-1-phosphate uridylyltransferase and glucokinase, respectively. This finding substantiates that the validamycin biosynthetic gene cluster harbors genes encoding the enzymes for UDP-glucose formation from glucose. Therefore, we propose that validamycin biosynthesis employs its own catalysts to generate UDP-glucose, but not depending on the primary metabolism.