• Korean Journal of Veterinary Research
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• v.38 no.2
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• pp.265-272
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• 1998

The effects of mixtures of diazinon(DA;5mg/kg), toxaphene(TOX;40mg/kg) and/or endrin(END; 5mg/kg) on the hepatic mixed-function oxygenase(MFO) system were stuided in ICR mice(18~22g) by oral intubation daily for 7 days. In general, TOX and TOX-containing mixtures were found to induced the metabolism of aminopyrine(22~60%), aniline(42~85%), phenacetin(145~194%) and benzo [a]pyrene(158~210%), and pentobaribtal biotransformation in the 9,000g liver supernatants and to increased the hepatic cytochrome p-450 contents(47~89%). Results of these may be, at least in part, associated with the MFO system. TOX pretreatment increased the aliesterase activity in the serum and liver homogenates and supernatants by 23~145%. The toxicity of TOX and TOX-containing mixtures would be lower than that of diazinon because of TOX-induced increase in the metabolism of diazinon(DA) or diazioxon(DO) and capability of TOX to stimulate the metabolism of diazinon and diazioxon and provide a pool of non-critical enzymes. These results suggest that this information might be helpful in the evaluation of the potential hazard due to occupational and/or environmental exposures to pesticides and their mixtures.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.1
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• pp.87-89
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• 2013

Glutathione S-transferases (GSTs) constitute a multigene family of multifunctional phase II metabolic enzymes. GSTT1, an important member of this group has a wide range of substrates including carcinogens. Total homozygous deletion or null genotype resulting in total lack of enzyme activity exists in populations for this enzyme. Since the null genotype may contribute to lower detoxification of carcinogens, this genotype is expected to increase cancer risk. The frequency of the GSTT1 null genotype is known to vary significantly among populations. However, little is known about its distribution in the hilly Kumaun region of northern India. Therefore, in this study, we determined the prevalence of the GSTT1 null polymorphism in the Kumaun popilation by conducting duplex PCR in 365 voluntary healthy individuals. The GSTT1 null genotype was detected in 18.4% of the individuals. Since GSTs play significant role in xenobiotic metabolism, the present data on GSTT1 genotype distribution should contribute in understanding genetic association with cancer risk in this understudied population.

• Biomedical Science Letters
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• v.19 no.1
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• pp.17-24
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• 2013

Animals show a sexual dimorphism in metabolic responses. We investigated to verify whether the peroxisome proliferator-activated receptor ${\alpha}$ ($PPAR{\alpha}$) agonist fenofibrate regulates obesity and skeletal muscle lipid metabolism with sexual dimorphism and to determine the changes in skeletal muscle expression of $PPAR{\alpha}$ target genes. After both sexes of C57BL/6J mice received a high fat diet with or without fenofibrate for 7 weeks, we examined the effects of fenofibrate on not only body weight, adipose tissue mass, and skeletal muscle lipid accumulation, but also the mRNA expression of $PPAR{\alpha}$-related genes in skeletal muscle. Male mice given a fenofibrate-supplemented high fat diet showed decreased body weight gain and adipose tissue mass compared with mice fed a high fat diet alone, whereas fenofibrate did not reduce them in high fat diet-fed female mice. Lipid accumulation in skeletal muscle was inhibited by fenofibrate in male mice, but not in female mice. Gene expression analysis revealed that fenofibrate increased the mRNA levels of $PPAR{\alpha}$ target enzymes only in male mice. Therefore, our results suggest that sex-dependence differences in obesity and intramuscular lipid levels under fenofibrate treatment could be due in part to the differences in skeletal muscle $PPAR{\alpha}$ activation between male and female mice.

• The Journal of Internal Korean Medicine
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• v.34 no.4
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• pp.375-383
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• 2013

Objectives : This study was performed to investigate the metabolic site of some medicinal herbs in the liver associated with CYP (Cytochrome P450). Methods : Cytochrome P450 is the major enzymes involved in drug metabolism and bioactivation. CYP3A4 and CYP2D6, the major CYP isoforms in humans, catalyse the major proportion of drugs available on the market. Scintillation proximity assay (SPA) is often used in studies to identify compounds that inhibit CYP3A4 and CYP2D6. 28 herbal extracts and radioisotopes were attached competitively to SPA beads, and followed by measuring the remaining radioisotopes in the medium. Erythromycin and dexamethasone, inhibitors of CYP3A4 and CYP2D6, were used as controls respectively. Results : Most of the 28 herbal extracts showed dose-dependent affinity to the CYP3A4 while some of the herbs showed affinity to the CYP2D6. Conclusions : These results suggest that most of the 28 herbal extracts are metabolized safely in the liver, combined with CYP3A4 and CYP2D6.

• Toxicological Research
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• v.18 no.3
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• pp.215-226
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• 2002

Acute or repeated physical exercise affects a large number of physiological parameters including hemodynamics, respiration, pH, temperature, gastrointestinal function and biotransformation, which determine the pharmacokinetics of drugs and chemicals. The rate and the amount of a chemical reaching the active site are altered by physical exercise, which results in significant changes in pharmacolosical/toxicological activity of the chemical. This aspect of physical exercise has vast implication in therapeutics and in safety evaluation, particularly for chemicals that have a low margin of safety. However there appears to be a wide inter- and intraindividual variation in the effects of physical exercise depend-ing on the duration, intensity and type of exercise, and also on the properties of each chemical. It is suggested that more studies need to be done to determine which factor(s) plays a major role in the disposition of chemicals in human/animals performing physical exercise. Certain chemicals induce severe toxicity due to metabolic conversion to reactive intermediate metabolites. it is suggested that repeated exercise may enhance the free radical scavenging system by increasing the activity of antioxidant enzymes. This area of research remain to be explored to elucidate the interaction of exercise and chemical on the antioxidant system.

• Journal of Plant Biology
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• v.20 no.2
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• pp.83-89
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• 1977

Changes in the alcohol-soluble free amino acids during germination of a spring grain, Wanju and two winter grains, Sedohadaka and Nonsankwa No.1-6 which are differing in their degree of spring (winter) habits, were investigated by thin layer chromatography. The results obtained are as follows. 1. Throughout the germination period, 25 ninhydrin positive components; 22 amino acids including two amides and 3 unknown spots were detected. It is interesting to note that identification of histidine was confined to Wanju and Sedohadaka but Nonsankwa No.1-6, which has the lower degree of spring habit. 2. Except the quiescent seeds, the major components were generally composed of the acidic and neutral amino acids together with glutamine and asparagine. 3. Proline was contained in higher quantity except from the stage of quiescent seeds, but the outstanding difference among the varieties was not recognized. Whether this component is related to the mechanism of spring habit in barley or not is a problem to be studied more. 4. In all the varieties, most of the changes in amino acid levels during germination were usually in the same direction and of the same pattern under the temperature controlled not to be varnalized. In view of the results above, the changes in the amino acid levels seem to be more affected by the changes of growing circumstances and the subsequent metabolic activities of certain enzymes than by the characteristics of varieties themselves.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2005.11a
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• pp.351-355
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• 2005

In the storage roots of sweetpotato (Ipomoea batatas (L.) Lam. cv. Kokei 14), 10 to 20% of starch is essentially unbranched linear amylose and the other major component is branched amylopectin. Amylose is produced by the enzyme GBSSI (granule bound starch synthase I), whereas amylopectin is produced by a concerted action of soluble starch synthase and starch branching enzymes (SBEI and SBEII). We constructed double-stranded RNA (dsRNA) interference vectors of GBSSI and IbSBEII and introduced them into sweetpotato genome via Agrobacterium-mediated gene transformation. The endogenous GBSSI expression was inhibited by dsRNA of GBSSI in 73 % of transgenic plants giving rise to the storage tubers containing amylopectin but not amylose. On the other hand, all sweetpotato plants transformed with dsRNA of IbSBEII contained a larger amount of amylose than the non-transgenic control (up to 25% compared to 10% in the controls). The RNA interference (RNAi) is effectively inhibited the gene expression in thestarch metabolic pathway and modified the characteristics of starch in sweetpotato.

• Asian-Australasian Journal of Animal Sciences
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• v.7 no.3
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• pp.303-316
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• 1994

Microbial digestion of feed in the rumen involves a sequential attack culminating in the formation of fermentation products and microbial cells that can be utilized by the host animal. Most feeds are protected by a cuticular layer which is in effect a microbial barrier that must be penetrated or circumvented for digestion to proceed. Microorganisms gain access to digestible inner plant tissues through damage to the cuticle, or via natural cell openings (e.g., stomata) and commence digestion from within the feed particles. Primary colonizing bacteria adhere to specific substrates, divide to form sister cells and the resultant microcolonies release soluble substrates which attract additional microorganisms to the digestion site. These newly attracted microorganisms associate with primary colonizers to form complex multi-species consortia. Within the consortia, microorganisms combine their metabolic activities to produce the diversity of enzymes required to digest complex substrates (e.g., cellulose, starch, protein) which comprise plant tissues. Feed characteristics that inhibit the microbial processes of penetration, colonization and consortia formation can have a profound effect on the rate and extent of feed digestion in the rumen. Strategies such as feed processing or plant breeding which are aimed at manipulating feed digestion must be based on an understanding of these basic microbial processes and their concerted roles in feed digestion in the rumen.

• Clinical and Experimental Pediatrics
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• v.48 no.12
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• pp.1295-1309
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• 2005

Nowadays, the nutritional deficits are rarely seen in Korea. However, an increased availability of the highly palatable energy dense, nutrient-poor foods increases the risks of obesity and deficits of vitamins and minerals in the general population. Also, optimum intake of vitamins and minerals, which varies with age and genetic back ground, might not suffice the poor, young, obese, and elderly people. Young girls and individuals participating in weight reductions and aesthetic components are prone to micronutrient deficiencies because they restrict food intake and specific micronutrient rich foods. An inadequate intake of vitamins or minerals is associated with reduced physical performance and exercise capacity, increased obesity, decreased cognitive function, increased DNA damages such as single- and double-stranded breaks or oxidative DNA lesions, and accelerated aging process and increased neuronal damages with mitochondrial oxidative decay. Most of these deleterious effects of the deficit could be prevented by a one tablet of multivitamins with a good balanced diet. High dose B vitamins are frequently administered to overcome the metabolic inadequacy to the people with the less functional enzymes with increased Km values for their coenzymes due to the single gene mutation or due to the single nucleotide polymorphisms. And some certain antioxidant vitamins are also used in large quantities to overcome the oxidative stress and to repair the damages. In this review, new nutritional concepts of some vitamins and minerals, which are widely used and useful for the children, will be discussed.

• Biomedical Science Letters
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• v.19 no.4
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• pp.310-314
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• 2013

CYP2E1 in the liver has been studied intensively because it is involved in the metabolic activation of xenobiotics. It is inducible by alcohol, so it has been suspected as the cause of cancer in the stomach and lung. The possible role of CYP2E1 has been suggested strongly as causing tissue damage in mice with renal failure. It was also suspected that 5'-flanking region of CYP2E1 gene might be involved with renal failure. So, we investigated polymorphism of restriction enzyme sites within CYP2E1 gene using the PCR-RFLP analysis. PstI and RsaI sites were located at 5'-flanking region and DraI site was located at intron 6. All three types (W/W, W/S, S/S) were observed for these enzymes although each incidence was somewhat different depending the enzyme sites. W/W was prominent for PstI whereas W/S was markedly high for RsaI. Overall, polymorphic incidence in patients was somewhat higher than normal population. This research should facilitate further investigation of CYP2E1 at genetic level as the direct cause of tissue damage in various organs.