• 공업화학
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• 제17권3호
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• pp.243-249
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• 2006

전기이중층 커패시터 및 리튬이온 2차전지의 compact화 하기 위하여 격리막과 전해질의 기능을 동시에 갖는 겔 전해질에 대한 연구가 광범위하게 진행되어 왔다. 본 연구는 고분자 겔 전해질에 다량의 기공을 형성하여 전해질의 함침성을 높이기 위해 물리적 특성이 우수한 고분자 지지체 P(VdF-co-HFP)/PVP에 개공제 PVP를 이용하였으며, 가소제 PC와 EC, 그리고 지지전해질 $TEABF_4$를 이용하여 고분자 겔 전해질을 제조하였다. 분말활성탄 BP-20과 MSP-20, 전도성 개량제 Super P 및 결합제 P(VdF-co-HFP)와 PVP를 사용한 전극과 결합하여 단위셀을 제작하였고, 고분자 겔 전해질과 단위셀의 전기화학적 특성을 고찰하였다. PVP 첨가량에 따른 고분자 겔 전해질의 이온전도도는 7 wt%일 때 가장 우수한 이온전도도를 보였으나, 단위셀을 구성하여 전기화학적 특성을 분석한 결과 AC-ESR은 3 wt%일 때 가장 우수하였다. 또한 단위셀을 구성하여 전기화학적 특성 분석 결과 PC : EC = 33 : 33 wt%일 때 가장 우수하였다. 또한 PC를 단독 사용시 보다 PC와 EC의 혼합물을 가소제로 사용하였을 때 비정전용량 등 전기화학적 특성이 높았다. 고분자 겔 전해질의 두께에 따른 이온전도도는 $20{\mu}m$일때 가장 우수한 결과를 보였으나, 단위셀을 구성하여 전기화학적 특성 분석 결과 $50{\mu}m$일 때 가장 우수한 사이클 특성을 나타내었다. 고분자 겔 전해질과 전극사이를 열 압착한 단위셀은 31.41 F/g의 높은 비정전용량과 안정한 전기화학적 특성을 나타내었다. 따라서 P(VdF-co-HFP : PVP = 20 : 3 및 PC : EC = 44 : 22 wt%로 제조된 EDLC용 고분자 겔 전해질의 최적 조성비는 23 : 66 : 11 wt%이었으며, 두께 $50{\mu}m$일 때 $3.17{\times}10^{-3}S/cm$의 이온전도도를 나타내었다. 이 때 단위셀의 전기화학적 특성은 DC-ESR $2.69{\Omega}$, 비정전용량 28 F/g 및 쿨롱 효율 100%이었다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권1호
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• pp.33-38
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• 2014

Background: Meningiomas are the second most common primary intracranial tumors after gliomas. Epigenetic biomarkers such as DNA methylation, which is found in many tumors and is thus important in tumorigenesis can help diagnose meningiomas and predict response to adjuvant chemotherapy. We investigated aberrant O6-methyl guanine methyltransferase (MGMT) methylation in meningiomas. Materials and Methods: Sixty-one patients were classified according to the WHO grading, and MGMT promoter methylation status was examined via the methylation-Specific PCR(MSP) method. Results: MGMT promoter methylation was found in 22.2% of grade I, 35% of grade I with atypical features, 36% of grade II, and 42.9% of grade III tumors. Conclusions: There was an increase, albeit not statistically significant, in MGMT methylation with a rise in the tumor grade. Higher methylation levels were also observed in the male gender.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제34권2호
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• pp.135-140
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• 2008

Loss of E-cadherin (E-cad) expression has been found in multiple cancers and is postulated to facilitate tumor cell dissociation and metastais. Promotor methylation may provides an alternative pathway for loss of gene function. This study evaluated the role of hypermethylation in the down-regulation of E-cad in oral squamous cell carcinoma (OSCC). We examined the E-cad expression by immunohistochemical staining and detected methylation status by methylation-specific polymerase chain reaction (MSP) in 20 OSCC tissues. Overally, 12 (60%) cases of hypermethylation of E-cad were detected and we found there were no correlation between methylation and age, histologic grade, lympn node metastasis, tumor size and clinical stage. However, Eleven (73.3%) of 15 samples which was negative for E-cad staining showed hypermethylation of E-cad promotor region. On the other hand, only one (20%) of 5 E-cad positive sample was observed with methylated status. The underexpression of E-cad was found to be related to promotor hypermethylation (p=0.035). In conclusion, we suggest that hypermethylation play a role in inactivation of E-cad gene and may be a appreciable biomarker for diagnosis and treatment of OSCC.

• 생물정신의학
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• 제8권2호
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• pp.239-245
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• 2001

Objective : Dopamine transporter is member of family of Na/Cl dependent neurotransmitter transporter, 12 transmembrane domain, that has high substrate specificity, affinity. It is related with dopamine reuptake in presynaptic vesicle. DAT has a VNTR in its 3'-untranslated region(UTR). 3'-UTR VNTR polymorphism is related with modification of dopamine transmission. The association between with VNTR polymorphism and neuropsychiatric disorders such as alcohol dependence, and low activity ALDH has been studied, but their relationship is unclear. We study about association of 3'-UTR VNTR of DAT gene and G2319A and alcohol dependence. Method : Group of Korean subjects were studied with alcohol dependence(n=49 male) compared to mentally healthy controls(n=53 male). The peripheral blood sample was acquired, and Polymerase Chain Reaction(PCR) amplification, MspI procedure was done. Result : There was a significant difference between alcohol dependence group and normal control(genotype frequency p<0.05, allele frequency p<0.05) Allele A frequency and genotype(GG, GA) frequency was a significant difference between alcohol dependence group and normal control(p<0.05). Conclusion : Our study showed that genetic polymorphism of DAT1 G2319A had relation with alcohol dependence.

• Journal of Microbiology and Biotechnology
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• 제16권2호
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• pp.193-199
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• 2006

Halotolerant spore-forming Gram-positive bacteria were isolated from the root, rhizosphere, and non-rhizosphere soil of Blutaparon portulacoides. The different isolates were characterized genetically using an amplified ribosomal DNA restriction analysis (ARDRA), and phenotypically based on their colonial morphology, physiology, and nutritional requirements. Three different 16S rRNA gene-based genotypes were observed at a 100% similarity using the enzymes HinfI, MspI, and RsaI, and the phenotypic results also followed the ARDRA groupings. Selected strains, representing the different ARDRA groups, were analyzed by 16S rDNA sequencing, and members of the genera Halobaeillus, Virgibacillus, and Oceanobacillus were found. Two isolates showed low 16S rDNA sequence similarities with the closest related species of Halobacillus, indicating the presence of new species among the isolates. The majority of the strains isolated in this study seemed to belong to the species O. iheyensis and were compared using an AP-PCR to determine whether they had a clonal origin or not. Different patterns allowed the grouping of the strains according to Pearson's coefficient, and the resulting dendrogram revealed the formation of two main clusters, denoted as A and B. All the strains isolated from the soil were grouped into cluster A, whereas cluster B was exclusively composed of the strains associated with the B. portulacoides roots. This is the first report on the isolation and characterization of halotolerant spore-forming Gram-positive bacteria that coexist with B. portulacoides. As such, these new strains may be a potential source for the discovery of bioactive compounds with industrial value.

• 한국물환경학회지
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• 제24권1호
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• pp.19-29
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• 2008

Hot air sparging is a groundwater remediation technique, in which organic contaminants volatilized into hot air from the saturated to vadose zone. In the laboratory diesel (10,000 mg TPH/kg) was spiked in contaminated saturated aquifer soil. The hot air ($34.9{\pm}2.7^{\circ}C$) was injected in intermittent (Q=1,500 mL/min, 10 minute injection and 10 minute idle) modes. We performed microcosm tests using the groundwater samples to assess TPH reductive remediation activity. For Terminal-Restriction Fragment Length Polymorphism (T-RFLP) analysis of eubacterial communities in sludge of wastewater treatment plants and soil of experiment site, the 16S rDNA was amplified by Polymerase Chain Reaction (PCR) from the sludge and the soil. The obtained 16S rDNA fragments were digested with Msp I and separated by electrophoresis gel. We found various sequence types for hot air sparging experiment with sludge soil samples that were closely related to Bacillus (149 bp, Firmicutes), Methlobacterium (149 bp, Euryarchaeotes), Pseudomonas (492 bp, ${\gamma}$-Proteobacteria), etc., in the clone library. In this study we find that TPH-water was reduced to 78.9% of the initial value in this experiment aquifer. The results of the present study suggests that T-RFLP method may be applied as a useful tool for the monitoring in the TPH contaminated soil fate of microorganisms in natural microbial community.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.597-598
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• 2005

Recently, the performance of portable electric equipment can often improved by a Li-ion battery assisted by a supercapacitor. A supercapacitor can provide high power density as well as a low resistance in the hybrid system. In this study, we have prepared, as the pluse power souce, a commercially supplied Li-ion battery with a capacity of 700mAh and AC resistivity of $60m\Omega$ at 1kHz and nonaqeous asymmetric hybrid capacitor composed of an activated carbon cathode and MCMB anode, and have examined the electrochemical characteristics of hybrid capacitor and the pulse performances of parallel connected battery/hybrid capacitor source. The nonaqueous asymmetric hybrid capacitor, the stacks of 10 pairs of the cathode, the porous separator and the anode electrode were housed in Al-laminated film cell. The hybrid capacitor, which was charged and discharged at a constant current at $0.25mA/cm^2$ between 3 and 4.3V, has exhibited the capacitance of 100F. And the equivalent series resistance was $32m\Omega$ at 1kHz. By combining a Li-ion battery and a hybrid capacitor, the pulse performance of battery can be improved 23% in run time under a pulse discharge of 7C-rate.

• Parasites, Hosts and Diseases
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• 제41권4호
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• pp.203-207
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• 2003

An ELISA was developed for the diagnosis of vivax malaria using multiple stage-specific recombinant antigens of Plasmodium vivax. The DNA from the whole blood of a malaria patient was used as template to amplify the coding regions for the antigenic domains of circumsporozoite protein (CSP-1), merozoite surface protein (MSP-1), apical merozoite antigen (AMA-1), serine repeat antigen (SERA), and exported antigen (EXP-1). Each amplified DNA fragment was inserted into pQE30 plasmid to induce the expression of His-tagged protein in Escherichia coli (M15 strain) by IPTG. His-tagged proteins were purified by Ni-NTA metal-affinity chromatography and used as antigens for ELISA with patient sera that were confirmed previously by blood smear examinations. When applied to patient sera, 122 (80.3%) out of 152 vivax malaria cases reacted to at least one antigen, while no reactions were observed with 128 uninfected serum samples. We applied this ELISA to the screening of 3,262 civilian residents in endemic regions near the DMZ, which resulted in 236 positively detected (7.2%) cases. This method can be applied to serological diagnosis and mass screening in endemic regions, or can be used as a safety test for transfusion blood in endemic areas.

• Journal of Plant Biotechnology
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• 제5권3호
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• pp.143-148
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• 2003

Bax, a mammalian pro-apoptotic member of the Bcl-2 family induces cell death when expressed in yeast. To investigate whether Bax expression can induce cell death in plant, we produced transgenic Arabidopsis plants that contained murine Bax cDNA under control of a glucocorticoid-inducible promoter. Transgenic plants treated with dexamethasone, a strong synthetic glucocorticoid, induced Bax accumulation and cell death, suggesting that some elements of cell death mechanism by Bax may be conserved among various organisms. Therefore, we developed novel yeast genetic system, and cloned several Plant Bax Inhibitors (PBIs). Here, we report the function of two PBIs in detail. PBI1 is ascorbate peroxidase (sAPX). Fluorescence method of dihydrorhodamine123 oxidation revealed that expression of Bax in yeast cells generated reactive oxygen species (ROS), and which was greatly reduced by co-expression with sAPX. These results suggest that sAPX inhibits the generation of ROS by Bax, which in turn suppresses Baxinduced cell death in yeast. PBI2 encodes nucleoside diphosphate kinase (NDPK). ROS stress strongly induces the expression of the NDPK2 gene in Arabidopsis thaliana (AtNDPK2). Transgenic plants overexpressing AtNDPK2 have lower levels of ROS than wildtype plants. Mutants lacking AtNDPK2 had higher levels of ROS than wildtype. $H_2O_2$ treatment induced the phosphorylation of two endogenous proteins whose molecular weights suggested they are AtMPK3 and AtMPK6. In the absence of $H_2O_2$ treatment, phosphorylation of these proteins was slightly elevated in plants overexpressing AtNDPK2 but markedly decreased in the AtNDPK2 deletion mutant. Yeast two-hybrid and in vitro protein pull-down assays revealed that AtNDPK2 specifically interacts with AtMPK3 and AtMPK6. Furthermore, AtNDPK2 also enhances the MSP phosphorylation activity of AtMPK3 in vitro. Finally, constitutive overexpression of AtNDPK2 in Arabidopsis plants conferred an enhanced tolerance to multiple environmental stresses that elicit ROS accumulation in situ. Thus, AtNDPK2 appears to playa novel regulatory role in $H_2O_2$-mediated MAPK signaling in plants.

• 생물정신의학
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• 제10권2호
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• pp.133-140
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• 2003

Objective:Some candidate gene polymorphisms were reported to be associated with tardive dyskinesia (TD). The aim of this study was to investigate the association of the 5-$HT_{2A}$ receptor gene polymorphisms with TD in Korean schizophrenic subjects. Method:Subjects were of 59 schizophrenic patients with TD and 60 schizophrenic patients without TD for studying of 5-$HT_{2A}$ receptor gene polymorphisms. TD was evaluated using the Abnormal Involuntary Movement Scale(AIMS). Genomic DNA was amplified by PCR and digestion with MspI and BsmI. Result:There were no statistically significant differences in the demographic variables, such as age, male to female percentage, duration of illnesses and duration of antipsychotic drug exposure between the TD group and control group. 1) T102C polymorphisms and TD Comparing the TD group and control group, the 102T/C allele was associated with a significantly increased risk for TD (${\chi}^2$=5.560, df=1, p=0.018). 2) Three AIMS categories of TD and T102C genotype. There were statistically significant differences in the three AIMS categories(${\chi}^2$=6.835, df=2, p=0.033). Conclusion:These result suggest 102T/C genotypes of the 5-$HT_{2A}$ receptor gene are related to the development of TD. The 102T/C genotypes were associated with significantly higher AIMS orofacial dyskinesia scores. These findings suggest that the 5-$HT_{2A}$ receptor gene is significantly associated with susceptibility to TD in patients with chronic schizophrenia.