• Journal of Microbiology
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• v.35 no.4
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• pp.264-270
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• 1997

The structure of plasmid mlp1, a linear 10.2kb mitochondrial plasmid of Pleurotus ostreatus NFF A2 was determined by restriction enzyme mapping and partial sequencing. The plasmid encodes at least two proteins; a putative RNA polymerase showing homology to yeast mitochondrial RNA polymerase and to viral-encoded RNA polymerases, and a putative DNA polymerase showing significant homology to the family B thpe DNA polymerases. It also contains terminal inverted repeat sequences at both ends which are longer than 274 bp. A 1.6 kb EcoRI restriction fragment of m1p1 containing the putative RNA polymerase gene did not hybridize to the nuclear or motochondrial genomes from P. ostreatus, suggesting that it may encode plasmidspecific RNA polymerase. The gene fragment also did not hybridize with the RNA polymerase gene (RPO41) from Saccaromyces cerevisiae. The relationship between genes in m1p1 and those in another linear plasmid pC1K1 of Claviceps purpurea was examined by DNA hybridization. The result indicates that the genes for DNA and RNA polymerases are not closely related with those in C. purpurea.

• Korean Journal of Ecology and Environment
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• v.38 no.spc
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• pp.39-43
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• 2005

The dynamics of water quality with the storm events were analyzed in a small reservoir for irrigation, Lake Wangkung. Water quality of the inflowing stream fluctuated seasonally with the variation of flow rate. Thermal stratification was consistent from April to October below 2 m depths and anoxic layer was developed below 2 m depth in summer. The unique feature of temperature showed that thermal stratification was disrupted by a heavy rain event during monsoon, but hypolimnetic hypoxia were reestablished after a few days. Phosphorus and nitrogen increased immediately following storm events. The marked increase may be due to the input of P-rich storm runoff from the watershed. Internal phosphorus loading can be one of the explanations for TP increases in summer. When there was a storm, total populations of phytoplankton and zooplankton was reduced immediately following the storm, indicating possible flushing of algae and zooplankton. After a lag period of low-density the plankton population bloomed to a peak again within five days after the storm. Turbid water in lake became clear again which coincided with the time of the phytoplankton buildup. The results demonstrate that water quality is regulated greatly by rainfall intensity in Lake Wangkung.

• IMMUNE NETWORK
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• v.22 no.4
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• pp.33.1-33.17
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• 2022

Suppressors of cytokine signaling (SOCS) have emerged as potential regulators of macrophage function. We have investigated mechanisms of SOCS3 action on type 2 macrophage (M2) differentiation induced by glucocorticoid using human monocytic cell lines and mouse bone marrow-derived macrophages. Treatment of THP1 monocytic cells with dexamethasone (Dex) induced ROS generation and M2 polarization promoting IL-10 and TGF-β production, while suppressing IL-1β, TNF-α and IL-6 production. SOCS3 over-expression reduced, whereas SOCS3 ablation enhanced IL-10 and TGF-β induction with concomitant regulation of ROS. As a mediator of M2 differentiation, glucocorticoid-induced leucine zipper (GILZ) was down-regulated by SOCS3 and up-regulated by shSOCS3. The induction of GILZ and IL-10 by Dex was dependent on ROS and p38 MAPK activity. Importantly, GILZ ablation led to the inhibition of ROS generation and anti-inflammatory cytokine induction by Dex. Moreover, GILZ knock-down negated the up-regulation of IL-10 production induced by shSOCS3 transduction. Our data suggest that SOCS3 targets ROS- and p38-dependent GILZ expression to suppress Dex-induced M2 polarization.

• Molecules and Cells
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• v.27 no.6
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• pp.651-656
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• 2009

The formation of ${\beta}$-amyloid peptide ($A{\beta}$) is initiated from cleavage of amyloid precursor protein (APP) by a family of protease, ${\alpha}$-, ${\beta}$-, and ${\gamma}$-secretase. Sub W, a substrate peptide, consists of 10 amino acids, which are adjacent to the ${\beta}$-cleavage site of wild-type APP, and Sub M is Swedish mutant with double mutations on the left side of the ${\beta}$-cleavage site of APP. Sub W is a normal product of the metabolism of APP in the secretary pathway. Sub M is known to increase the efficiency of ${\beta}$-secretase activity, resulting in a more specific binding model compared to Sub W. Three-dimensional structures of Sub W and Sub M were studied by CD and NMR spectroscopy in water solution. On the basis of these structures, interaction models of ${\beta}$-secretase and substrate peptides were determined by molecular dynamics simulation. Four hydrogen bonds and one water-mediated interaction were formed in the docking models. In particular, the hydrogen bonding network of Sub M-BACE formed spread over the broad region of the active site of ${\beta}$-secretase (P5-P3'), and the side chain of P2- Asn formed a hydrogen bond specifically with the side chain of Arg235. These are more favorable to the cleavage of Sub M by ${\beta}$-secretase than Sub W. The two substrate peptides showed different tendency to bind to ${\beta}$-secretase and this information may useful for drug development to treat and prevent Alzheimer's disease.

• Nuclear Engineering and Technology
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• v.38 no.5
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• pp.399-404
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• 2006

Noninvasive molecular targeting in living subjects is highly demanded for better understanding of such diverse topics as the efficient delivery of drugs, genes, or radionuclides for the diagnosis or treatment of diseases. Progress in molecular biology, genetic engineering and polymer chemistry provides various tools to target molecules and cells in vivo. We used chitosan as a polymer, and $^{99m}Tc$ as a radionuclide. We developed $^{99m}Tc-galactosylated$ chitosan to target asialoglycoprotein receptors for nuclear imaging. We also developed $^{99m}Tc-HYNIC-chitosan-transferrin$ to target inflammatory cells, which was more effective than $^{67}Ga-citrate$ for imaging inflammatory lesions. For an effective delivery of molecules, a longer circulation time is needed. We found that around 10% PEGylation was most effective to prolong the circulation time of liposomes for nuclear imaging of $^{99m}Tc-HMPAO-labeled$ liposomes in rats. Using various characteristics of molecules, we can deliver drugs into targets more effectively. We found that $^{99m}Tc-labeled$ biodegradable pullulan-derivatives are retained in tumor tissue in response to extracellular ion-strength. For the trafficking of various cells or bacteria in an intact animal, we used optical imaging techniques or radiolabeled cells. We monitored tumor-targeting bacteria by bioluminescent imaging techniques, dentritic cells by radiolabeling and neuronal stem cells by sodium-iodide symporter reporter gene imaging. In summary, we introduced recent achievements of molecular nuclear imaging technologies in targeting receptors for hepatocyte or inflammatory cells and in trafficking bacterial, immune and stem cells using molecular nuclear imaging techniques.

• The Journal of the Korea Contents Association
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• v.14 no.6
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• pp.339-354
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• 2014

As Hallyu has been spreading and influencing on global pop culture, the Hallyu audiences respond more diverse to Hallyu. This research focuses on the importance of international co-production between Korea and the countries receiving Hallyu and highlights on the roles of global media companies. To do so, this research introduces the international co-production cases in Vietnam which can be the center of spreading Hallyu in Southeast Asia countries. The research resources are journal articles, newspapers, and the parts of the Focus Group Discussion in Vietnam. The international co-productions between Korea and the countries can provide the opportunity for diversifying Hallyu contents and for communicating with Hallyu receivers better. This research considers the development trends of Hallyu contents based on the cases of CJ E&M in Vietnam and emphasizes building cooperative relationships with Vietnam cultural industry. Furthermore, it is necessary to support the number of Korean media companies to create contents and build networks so that the companies can advance to global media market.

• Archives of Pharmacal Research
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• v.28 no.6
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• pp.716-721
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• 2005

Fluoxetine is an anorexic agent known to reduce food intake and weight gain. However, the molecular mechanism by which fluoxetine induces anorexia has not been well-established. We examined mRNA expression levels of neuropeptide Y (NPY) and proopiomelanocortin (POMC) in the brain regions of rats using RT-PCR and in situ hybridization techniques after 2 weeks of administering fluoxetine daily. Fluoxetine persistently suppressed food intake and weight gain during the experimental period. The pair-fed group confirmed that the reduction in body weight in the fluoxetine treated rats resulted primarily from decreased food intake. RT-PCR analyses showed that mRNA expression levels of both NPY and POMC were markedly reduced by fluoxetine treatment in all parts of the brain examined, including the hypothalamus. POMC mRNA in situ signals were significantly decreased, NPY levels tended to increase in the arcuate nucleus (ARC) of fluoxetine treated rats (compared to the vehicle controls). In the pair-fed group, NPY mRNA levels did not change, but the POMC levels decreased (compared with the vehicle controls). These results reveal that the chronic administration of fluoxetine decreases expression levels in both NPY and POMC in the brain, and suggests that fluoxetine-induced anorexia may not be mediated by changes in the ARC expression of either NPY or POMC. It is possible that a fluoxetine raised level of 5-HT play an inhibitory role in the orectic action caused by a reduced expression of ARC POMC ($\alpha$-MSH).

• Journal of Acupuncture Research
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• v.17 no.2
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• pp.247-259
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• 2000

Objective : The mechanism of acupuncture to increase cerebral blood flow is still uncertain. The purpose of this study was to evaluate the neural basis of acupuncture by comparing the cerebral regions activated by the stimulation of two different methods of acupunctures at the same acupoint which was suggested by oriental medicine to increase rCBF. Materials and Methods : Thirty-nine healthy volunteers(26 males, 13 females, age $31{\pm}11$ years) were studies by rest/acupuncture Tc-99m ECD brain SPECT using a subtraction method. SPECTs using two methods(needle retention and heated needle with 90% alcohol) at two acupoints (right LI. 4 and ST. 36) were peformed at an interval of three days. For the needle retention method, acupuncture needle was inserted to a depth of about 2 cm into each acupoint 8 minutes after the lst acquisition and continued to retain, and the second injection of Tc-99m ECD was done 15 minutes after the insertion of needle. For the heated acupuncture method, heated needle was inserted in a twinkle within several msec 20 second after the second injection of Tc-99m ECD. The differences of between rest and acupuncture activation state were statistically analyzed using a statistical parametric mapping software. Result : Acupunctures of both methods reveal similar patterns of increase in rCBF. Acupuncture at ST.36 increase rGBF in left anterior temporal, right inferior frontal lobes, and left cerebellum. Acupuncture at LI. 4 increase rCBF in the left frontal cortex, right temporal pole, both inferior frontal cortices and right cerebellum. Conclusion : The effects of two different acupunctures to the same acupoints on rCBF were similar. Therefore, this result suggests Chat the mechanism of acupuncture in the increase of cerebral blood flow have a neural basis.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.1
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• pp.7-15
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• 2004

This research was designed to investigate the antioxidant activity of red cabbage (Brassica oleracea L., BO) fractions on the liposomes consisted of L-$\alpha$-dilinoleoylphosphatidylcholine (DLPC-liposome) and the tyrosinase activity of BO fractions. The methanol extract of BO (BOM) was fractionated into five different partition layers: hexane (BOMH), ethylether (BOMEE), ethylacetate (BOMEA), butanol (BOMB) and aqueous (BOMA) layers. The antioxidant activities of BOM fractions toward oxidized DLPC-liposome were examined by spectrophotometry measuring oxidized conjugated dines. The antioxidant activities of BOMEE and BOMEA fractions toward oxidized DLPC-liposomes were similar to the antioxidant activities of $\alpha$-tocopherol and weaker than that of BHT. The synergy effects of antioxidation of BOMEE and BOMEA fractions added with vitamin C and $\alpha$-tocopherol had even stronger antioxidant activities than the fractions without vitamin C and $\alpha$-tocopherol. These results showed that the fractions of BOMEE and BOMEA could be developed as a potent antioxidant. Out of five different partition layers of BOM fractions, BOMEA exhibited the strongest tyrosinase activity of 94% at a concentration of 40 $\mu\textrm{g}$/mL. This result suggests BOMEA fractions inhibit the foramation of melanin and therefore can be used as the inhibitor of melanin synthesis. Results of antioxidant activity and tyrosinase inhibition indicate that useful bioactive substances exist in BOMEE and BOMEA fractions. Both fractions from BO (red cabbage) have the potential of being developed into health related products.

• Journal of Radiation Protection and Research
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• v.28 no.2
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• pp.117-125
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• 2003

It was reported that radiopharamaceuticals induced radiation adaptive response (RAR) in patients undergoing nuclear medicine imaging studies. Individual variations of RAR were not studied well. The purpose of this study was to evaluate individual variation of RAR in patients undergoing nuclear medicine imaging studies. Peripheral lymphocytes were collected from 23 patients undergoing $^{99m}Tc-diethylenetriamine$ pentaacetic acid $(^{99m}Tc-DTPA)$ renal scintigraphy, 18 patients undergoing $^{99m}Tc-methylene$ diphosphonate $(^{99m}Tc-MDP)$ bone scintigraphy and 21 patients undergoing $^{99m}Tc-tetrofosmin\;(^{99m}Tc-TF)$ scintigraphy were collected before and 4 hours after injection of radiopharmaceuticals. The lymphocytes were exposed to challenge dose of 2 Gy gamma rays using a cell irradiator. Numbers of ring-form (R) and dicentric (D) chromosomes were counted under the light microscope. and used to calculate the frequency of chromosomal aberration [Ydr=(D+R)/total number of counted lymphocytes]. Adaptation index (k) was defined 3s ratio of Ydr in conditioned lymphocytes over Ydr in unconditioned lymphocytes. Coefficients of variance of k in $^{99m}Tc-DTPA,\;^{99m}Tc-MDP\;and\;^{99m}Tc-TF$ were 35%, 34% and 21%, respectively k was not dependent upon age, sex, and underlying diseases. There was a wide variation of RAR induced by radiopharmaceuticals among patients undergoing nuclear medicine procedures. It remains to be determined for causes of such variation.