• Journal of Ecology and Environment
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• v.33 no.3
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• pp.261-270
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• 2010

Increasing atmospheric $CO_2$ affects the soil carbon cycle by influencing microbial activity and the carbon pool. In this study, the effects of elevated $CO_2$ on extracellular enzyme activities (EEA; ${\beta}$-glucosidase, N-acetylglucosaminidase, aminopeptidase) in salt marsh sediment vegetated with Suaeda japonica were assessed under ambient atmospheric $CO_2$ concentration (380 ppm) or elevated $CO_2$ concentration (760 ppm) conditions. Additionally, the community structure of sulfate-reducing bacteria (SRB) was analyzed via terminal restriction fragments length polymorphism (T-RFLP). Sediment with S. japonica samples were collected from the Hwangsando intertidal flat in May 2005, and placed in small pots (diameter 6 cm, height 10 cm). The pots were incubated for 60 days in a growth chamber under two different $CO_2$ concentration conditions. Sediment samples for all measurements were subdivided into two parts: surface (0-2 cm) and rhizome (4-6 cm) soils. No significant differences were detected in EEA with different $CO_2$ treatments in the surface and rhizome soils. However, the ratio of ${\beta}$-glucosidase activity to N-acetylglucosaminidase activity in rhizome soil was significantly lower (P < 0.01) at 760 ppm $CO_2$ than at 380 ppm $CO_2$, thereby suggesting that the contribution of fungi to the decomposition of soil organic matter might in some cases prove larger than that of bacteria. Community structures of SRB were separated according to different $CO_2$ treatments, suggesting that elevated $CO_2$ may affect the carbon and sulfur cycle in salt marshes.

• Advances in Traditional Medicine
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• v.7 no.4
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• pp.357-362
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• 2007

Cytochrome P450 2C19 (CYP2C19) is a clinically important enzyme involved in the metabolism of therapeutic drugs, including (S)-mephenytoin, omeprazole, proguanil, and diazepam. Individuals are characterized as either extensive metabolizers (EM) or poor metabolizers (PM) on the basis of CYP2C19 enzyme activity. The PM phenotype occurs in 2-5% of Caucasians, but in 18-23% of Asians. To clarify the association between CYP2C19 polymorphisms and gastric cancer in Koreans, we investigated CYP2C19 genotypes ($CYP2C19^*1,\;{^*2},\;and\;^*3$) in 109 patients with gastric cancer and 211 controls. Normal ($CYP2C19^*1$) and defective alleles were detected with polymerase chain reaction/restriction enzyme analysis. CYP2C19 has three hereditary genotypes: homozygous EM, with high enzymatic activity; heterozygous EM, with moderate enzymatic activity; and PM, with no enzyme activity. We found that CYP2C19 heterozygous EM is more closely associated with gastric cancer than is homozygous EM. Because the CYP2C19 genotype varies in Koreans, a genotyping test is desirable to prevent gastropathy recurrence in patients before their doses of omeprazole are reduced during maintenance therapy.

• Korean Journal of Microbiology
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• v.44 no.3
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• pp.199-202
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• 2008

A white rot fungus Irpex lacteus produced lignin degrading enzymes, which showed degrading activity against various recalcitrant compounds. However, laccase, one of the lignin degrading enzymes, was too low to be assayed by spectrophotometry using o-tolidine as the chromogenic substrate in this fungus under various culture conditions. A laccase expression vector was constructed using a cDNA from Phlebia tremellosa with the constitutively expressed promoter of glyceraldehydes-3-phosphate dehydrogenase gene, and introduced into I. lacteus by the restriction enzyme mediated integration transformation through the protoplast-$CaCl_2$ procedure. Two transformants showed highly increased laccase activities at the early growth phase in the minimal liquid medium, and they not only degraded bisphenol A, a notorious endocrine disrupting chemical, but also removed the estrogenic activity effectively.

• Archives of Plastic Surgery
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• v.37 no.2
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• pp.191-194
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• 2010

Treatments of severely incurved toenails cause anatomical changes and cosmetic problems, even though they provide adequate symptom relief. Incurved toenail patients treated with a K-D$^{(R)}$ (S&C Biotech, Seoul, South Korea) the new device for correcting curved nail deformity were investigated retrospectively. This study surveyed 12 patients(18 cases) who had been treated for severe ingrown toenails using K-D$^{(R)}$ from May 2008 to March 2009, and examined their subjective satisfaction before and after the treatment. The average age of the participants was 39 (ranging from 27 to 52), and 8 of them were male and 4 female. The treatment was applied after the patients were given a thorough explanation about the tool and the treatment, and questionnaire surveys were conducted before the treatment and after 3 months on the average from the treatment. In the survey, the respondents were asked about pain, restriction on activities, and the selection of shoes. For each item, symptoms with a given point were presented, and the respondents' scores were compared between the surveys before and after the treatment. According to the results of the questionnaire survey, pain increased from 14 out of 40 before the treatment to 39 after, activity restriction increased from 11 to 30, and shoe selection increased from 20 to 30. The average total score increased from 45 to 98, and this suggests a considerable enhancement in the patients' subjective satisfaction. The average period of the application of K-D$^{(R)}$ was $20.3{\pm}9.4$ days, and in all the cases, ingrown toenails were corrected within three weeks.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.178-178
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• 1994

Hepatitis B Virus (HBV) is a DNA virus with a 3.2kb partially double-stranded genome. The life cycle of the virus involves a reverse transcription of the greater than genome length 3.5kb mRNA. This pegenomic RNA contains all the genetic information encoded by the virus and functions as an intermediate in viral replication. Tumor suppressor p53 has previously been shown to interact with the X-gene product of the HBV, which led us to hypothesize that p53 may act as a negative regulator of HBV replication and the role of the X-gene product is to overcome the p53-mediated restriction. As a first step to prove the above hypothesis, we tested whether p53 represses the propagation of HBV in in vitro replication system. By transient cotransfection of the plasmid containing a complete copy of the HBV genome and/or the plasmid encoding p53, we found that the replication of HBV is specifically blocked by wild-type p53. The levels of HBV DNA, HBs Ag and HBc/e Ag secreted in cell culture media were dramatically reduced upon coexpresion of wild-type p53 but not by the coexpression of the mutants of p53 (G154V and R273L). Furthermore, levels of RNAs originated from HBV genome were repressed more than 10 fold by the cotransfection of the p53 encoding plasmid. These results clearly states that p53 is a nesative regulator of the HBV replication. Next, to addresss the mechanism by which p53 represses the HBV replication, we performed the transient transfection experiments employing the pregenomic/core promoter-CAT(Chloramphenicol Acetyl Transferase) construct as a reporter. Cotransfection of wild-type p53 but not the mutant p53 expression plasmids repressed the CAT activity more than 8 fold. Integrating the above results, we propose that p53 represses the replication of HBV specifically by the down-regulation of the pregenomic/core promoter, which results in the reduced DNA synthesis of HBV. Currently, the mechanism by which HBV overcomes the observed p53-mediated restriction of replication is tinder investigation.

• Proceedings of the Korean Society of Life Science Conference
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• 2000.06a
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• pp.9-10
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• 2000

The aging process is multifactorial and results from the combined effects of inherited(genetic) and acquired factors including life style, food habits, physical activity, and diseases. That give rise to the various approaches in aging. We are trying to study biological changes with aging, In detail we are focused on gene and protein function accompanied by normal or abnormal aging process, especially our efforts are aimed at revealing the functional relationship of proteins in aging as a final product of gene. We expect that proteomic approach to the study of protein function involved in aging should give us variety of integrated data to understand biological changes of long lived lives, We have applied expression proteomics to rat liver bred in dietary restriction or in at libitum to elucidate the effects of food habit on aging. Expression proteomics shows us protein profile in a selected tissue or cells as a whole and gives us the information about protein expression level, posttranslational modification and degenerative modification of expressed proteins. Comparative analysis of young and old rat liver by two dimensional gels shows that gene expression of several proteins was down regulated in old rats and some protein expression level is increased with aging. Dietary restriction slows down these changes of gene expression and in some proteins there's no difference in protein expression level at same ages in comparison with rats bred in at libitum. About forty protein was identified by peptide mass fingerprint with MALDI-TOF and rest of the protein of interest is in the course of identification, Also we are trying to make mitochondrial and cytosolic proteom reference map. These suborganelle proteom map will gives us the information about low abundance proteins and cellular localization of proteins. Proteomics is a growing methodology to study biological system. High throughput qualitative and qualitative aspect of this approach will gives us large amount of integrated information and speed up our understanding about biological system

• Journal of Microbiology
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• v.34 no.4
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• pp.355-362
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• 1996

Complementation cloning of the argC, E, B, D, F, and G genes in Corynebacterium glutamicum was done by transforming the genomic DNA library into the corresponding arginine auxotrophs fo Escherichia coli. Recombinant plasmids containing 6.7 kb and 4.8kb fragments complementing the E. coli argB mutant were also able to complement the E. coli argC, E, A, D, and F mutants, indicating the clustered organization of the arginine biosynthetic genes within the cloned DNA fragments. The insert DNA fragments in the recombinant plasmids, named pRB1 AND pRB2, were physically mapped with several restriction enzymes. By further subcloning the entire DNA fragment containing the functions and by complementation analysis, we located the arg genes in the order of ACEBDF on the restriction map. We also determined the DNA nucleotide sequence of the fragment and report here the sequence of the argB gene. When compared to that with the mutant strain, higher enzyme activity of N-acetylglutamate kinase was detected in the extract of the mutant carrying the plasmid containing the putative argB gene, indicating that the plasmid contains a functional argB gene. Deduced amino acid sequence of the argB gene shows 45%, 38%, and 25% identity to that from Bacillus strearothermophilus, Bacillus substilus, and E. coli respectively. Our long term goal is genetically engineering C. glutamicum which produces more arginine than a wild type strain does.

• Microbiology and Biotechnology Letters
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• v.20 no.2
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• pp.136-142
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• 1992

Bacillus stearothemophilus isolated from soil was identified to express multiple extracellular xylanases. Two HindIII restriction fragments of 5.4 and 6.4 kb from B. stearothermophilus genomic DNA were cloned into pBR322 to obtain recombinant plasmids pMG0l and pMG02, respectively, which enabled E. coli HBlOl cells to produce $\beta$-D-xylosidase activity. By subcloning into pUC18 and Southern blotting, the loci of the $\beta$-D-xyiosidase genes were elucidated to be on non-homologous DNA fragments of 2.2 kb from pMGOl(pMG1) and 1.0 kb from pMG02(pMG2), respectively. The two enzymes produced in E. coli cleaved xylobiose, xylotriose, xylotetrose and xylotetrose to produce xylose as a major end product. The gene on pMG1, distinct from that on pMG2 was observed to encode a bifunctional protein that displayed both P-D-xylosidase (EC.3.2.1.37) and a-L-arabinofuranosidase activities (EC.3.2.1.55).

• ALGAE
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• v.21 no.2
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• pp.261-266
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• 2006

The innate soluble polysaccharides and phenolic compounds of marine macroalgae are serious contaminants which interfere with experimental procedures such as restriction enzyme digestion, polymerase chain reaction (PCR) and other enzymatic reactions using extracted DNA samples. The viscous polysaccharides are co-precipitated with DNA samples by isopropanol or ethanol precipitation in conventional experiment. To overcome the problem, a method for the isolation of high molecular weight DNA from Porphyra tenera is developed with the application of diatomaceous earth column. The isolated DNAs by this method were about 50-100 kb in size and could be digested well with restriction enzymes. The nuclease activity seemed to be minimal, and high reproducibility in the arbitrary primed PCR for RAPD analyses was a distinctive feature. These results suggest that this method is very efficient in isolating nucleic acid from macroalgae including Porphyra.

• International Journal of Industrial Entomology and Biomaterials
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• v.39 no.1
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• pp.1-8
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• 2019

Steamed and freeze-dried mature silkworm powder (SMSP) is a natural food containing a large amount of various functional materials and has various health promoting effects. SMSP is known to increase the life expectancy and healthspan, simultaneously. The accomplishment of extension of healthspan should be possible to achieve by activating various signaling pathways delaying aging in various tissues, not by regulating only a few signaling pathways. Consistent with this notion, SMSP increased the resistant to Parkinson disease by enhancing olfaction and mitochondrial activity in neurons of animal models. In addition, SMSP could enhance the gastrointestinal functions. The animals consumed SMSP showed enhanced alcohol metabolisms, reduced cholesterols in bloods, increased resistance to carcinogens causing liver cancers, and protective effects in alcohol induced stomach ulcers. Furthermore, SMSP was also effective in appearance. The SMSP consumed animals showed reduced skin pigmentations and more hair growth compared with control animals. Taken together, the functional enhancement effects of SMSPs in various tissues and organs, which have been discovered to date, are combined to extend healthspan. Therefore, SMSP can be regarded as calorie restriction mimetics. Further studies in the health promoting effects of SMSP will contribute to identifying new applicable diseases, resulted in increased sales of SMSP and incomes of sericulture farmers.