• Journal of Microbiology and Biotechnology
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• v.28 no.7
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• pp.1122-1132
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• 2018

In this study, we attempted to find new and efficient microbial enzymes for producing rare sugars. A ribose-5-phosphate isomerase B (OsRpiB) was cloned, overexpressed, and preliminarily purified successfully from a newly screened Ochrobactrum sp. CSL1, which could catalyze the isomerization reaction of rare sugars. A study of its substrate specificity showed that the cloned isomerase (OsRpiB) could effectively catalyze the conversion of $\text\tiny{L}$-rhamnose to $\text\tiny{L}$-rhamnulose, which was unconventional for RpiB. The optimal reaction conditions ($50^{\circ}C$, pH 8.0, and 1 mM $Ca^{2+}$) were obtained to maximize the potential of OsRpiB in preparing $\text\tiny{L}$-rhamnulose. The catalytic properties of OsRpiB, including $K_m$, $k_{cat}$, and catalytic efficiency ($k_{cat}/K_m$), were determined as 43.47 mM, $129.4sec^{-1}$, and 2.98 mM/sec. The highest conversion rate of $\text\tiny{L}$-rhamnose under the optimized conditions by OsRpiB could reach 26% after 4.5 h. To the best of our knowledge, this is the first successful attempt of the novel biotransformation of $\text\tiny{L}$-rhamnose to $\text\tiny{L}$-rhamnulose by OsRpiB biocatalysis.

• Reproductive and Developmental Biology
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• v.32 no.3
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• pp.167-173
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• 2008

Somatic cells such as oviduct epithelial cell, uterine epithelial cell, cumulus-granulosa cell and buffalo rat river cell has been used to establish an effective culture system for bovine embryos produced in in vitro. But nitric oxide (NO) metabolites secreted from somatic cells were largely arrested the development of bovine in vitro matured/ in vitro fertilized (IVM/IVF) embryos, suggesting that NO was induced the embryonic toxic substance into culture medium. The objective of this study was to investigate whether BOEC co-culture system can ameliorate the NO-mediated oxidative stress in the culture of bovine IVM/IVF embryos. Therefore, we evaluated the developmental rate of bovine IVM/IVF embryos under BOEC co-culture system in the presence or absence of sodium nitroprusside (SNP), as a NO donor, and also detected the expression of growth factor (TGF-$\beta$, EGF and IGFBP) and apoptosis (Caspase-3, Bax and Bcl-2) genes. The supplement of SNP over 5 uM was strongly inhibited blastocyst development of bovine IVM/IVF embryos than in control and 1 uM SNP group (Table 2). The developmental rates beyond morulae stages of bovine IVM/IVF embryos co-cultured with BOEC regardless of SNP supplement (40.4% in 5 uM SNP+ BOEC group and 65.1% in BOEC group) were significantly increased than those of control (35.0%) and SNP single treatment group (23.3%, p<0.05: Table 3). The transcripts of Bax and Caspase-3 genes were detected in all experiment groups (1:Isolated fresh cell (IFC), 2:Primary culture cell (PCC), 3:PCC after using the embryo culture, 4: PCC containing 5 uM SNP and 5: PCC containing 5 uM SNP after using the embryo culture), but Bcl-2 gene was not detected in IFC and PCC (Fig. 1). In the expression of growth factor genes, TGF-$\beta$ gene was found in all experimental groups, and EGF and IGFBP genes were not found in IFC and PCC (Fig. 2). These results indicate that BOEC co-culture system can increase the development beyond morula stages of bovine IVM/IVF embryos, possibly suggesting the alleviation of embryonic toxic substance like nitric oxide.

• The Journal of Internal Korean Medicine
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• v.27 no.2
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• pp.336-344
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• 2006

Objects : This study has been carried out to assess the effects of the variable herbs on $IFN-{\gamma}$ secretion in the mouse spleen cell. Methods : 202 kinds of herb extracts were used to evaluate the $IFN-{\gamma}$ secretory distinction by each $1{\mu}g/ml$ and $10{\mu}g/ml$ density of water. All experimental herbs were grouped by oriental herbalogical method. But each herb had its independent variables. Results : The secretions increased in 20% of all herbal water. The density differences also make different effects on the secretion of $IFN-{\gamma}$. The secretion of IFN-${\gamma}$ inclosed in some kinds of herbs of IFN-${\gamma}$. It has representatively increased in Imperaetae Rhizoma(白茅根) of $1{\mu}g/ml$ and Notopterygii Rhizoma(羌活)of $10{\mu}g/ml$. $IFN-{\gamma}$ incresed in 12 kinds of heybs of both densities. The secretion of $IFN-{\gamma}$ decreased in some kinds of herbs of $IFN-{\gamma}$. It has representatively decreased in Moutan Radicis Cortex(蘇丹皮) of $1{\mu}g/ml$ and Angelicae Radix(富歸尾) of $10{\mu}g/ml$. $IFN-{\gamma}$ decreased in 18 kinds of herbs of both densities. In t oriental herb group, The secretion of $IFN-{\gamma}$ increased in Bang-Hyang-Hwa-Sup group(芳香化濕藥), He-Pyo group(解表藥), I-Su-Sam-SuP group(利水渗) The secretion of $IFN-{\gamma}$ decreased in Gu-Chung group(驅蟲藥), An-Sin group(安神藥). Su-Sap group(收澁) On-Li group(溫裏藥), I-Gi group(利氣藥). Conclusions : The result of this study will not only broaden applications of oriental medicine to biological therapy, but also form the basis of oriental medical therapy to find out the meaning of oriental classification.

• Parasites, Hosts and Diseases
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• v.52 no.1
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• pp.93-97
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• 2014

Subolesin (4D8), the ortholog of insect akirins, is a highly conserved protective antigen and thus has the potential for development of a broad-spectrum vaccine against ticks and mosquitoes. To date, no protective antigens have been characterized nor tested as candidate vaccines against Dermacentor silvarum bites and transmission of associated pathogens. In this study, we cloned the open reading frame (ORF) of D. silvarum 4D8 cDNA (Ds4D8), which consisted of 498 bp encoding 165 amino acid residues. The results of sequence alignments and phylogenetic analysis demonstrated that D. silvarum 4D8 (Ds4D8) is highly conserved showing more than 81% identity of amino acid sequences with those of other hard ticks. Additionally, Ds4D8 containing restriction sites was ligated into the pET-32(a+) expression vector and the recombinant plasmid was transformed into Escherichia coli rosetta. The recombinant Ds4D8 (rDs4D8) was induced by isopropyl ${\beta}$-D-thiogalactopyranoside (IPTG) and purified using Ni affinity chromatography. The SDS-PAGE results showed that the molecular weight of rDs4D8 was 40 kDa, which was consistent with the expected molecular mass considering 22 kDa histidine-tagged thioredoxin (TRX) protein from the expression vector. Western blot results showed that rabbit anti-D. silvarum serum recognized the expressed rDs4D8, suggesting an immune response against rDs4D8. These results provided the basis for developing a candidate vaccine against D. silvarum ticks and transmission of associated pathogens.

• The Korean Journal of Food And Nutrition
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• v.26 no.3
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• pp.565-572
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• 2013

This study was performed to optimize the processing conditions and to select the optimum species for colored sweet potato chips (Shinjami, Juhwangmi and Hayanmi varieties) baked by far-infrared radiation. Sweet potato chips were prepared by different slicing thickness (1~3 mm), concentration of sucrose solution for soaking (15~30%), blanching time (15~60 sec), baking temperature ($110{\sim}140^{\circ}C$) and baking time (23~31 min) through sensory evaluation and failure stress measurement. Optimal processing condition of sweet potato chips using Shinjami was determined to 1 mm, 20%, 45 sec, $120^{\circ}C$ and 31 min, and those using Juhwangmi was determined as 1 mm, 25%, 45 sec, $130^{\circ}C$ and 29 min. Sweet potato chips using Hayanmi was determined as 1 mm, 20%, 45 sec, $120^{\circ}C$ and 31 min, respectively. Free sugar content of sweet potato chips was higher in chips than in raw materials. In the sensory evaluation, appearance, sweet taste, hardness, and overall acceptance were higher in Juhwangmi than in the Shinjami and Hayanmi varieties. Overall acceptance, sugar content, b-value and failure stress were highly correlated among factors affecting the sensory characteristics (p<0.01). From the results of this study, Juhwangmi variety was selected for production of sweet potato chips.

• Molecular & Cellular Toxicology
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• v.4 no.4
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• pp.278-284
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• 2008

The X-linked inhibitor of apoptosis (XIAP) is a member of a novel family of inhibitors of apoptosis and has several BIR domains (BIR1, BIR2, and BIR3) and a carboxy-terminal RING zinc-finger. Since suppressionof apoptosis is fundamentally important for carcinogenesis and tumor growth, we investigated the expression and function of XIAP in DEN-induced carcinogenesis using rat model. Wistar rats were injected intraperitoneally with DEN at a dose of 50 mg/kg in twice a week for 12 weeks (Group II) and 16 weeks (Group III) followed by the recovery periods, respectively. The evaluation of DEN-induced carcinogenesis carried out the blood, RT-PCR, histopathological and western blot analysis. The level of blood chemistry including GOT/GPT, albumin, and total bilirubin were significantly exchanged comparing to control and Group I/Group II. The expression of albumin and collagen mRNA were significantly exchanged (P<0.05) in both groups. In addition, AFP mRNA expression decreased more after recovery periods than Group II. XIAP was expressed constitutively in normal rat liver as well as DEN-induced Groups I and Group II. In addition, XIAP expression increased more in Group I with 4 weeks recovery periods than Group I. However, XIAP expression shown to increase in Group lI, otherwise, it was decreased in Group II with 10 weeks repair periods. Taken together, these results suggest the alteration of XIAP expression could be involved in hepatocellular carcinogenesis.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.120-120
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• 2011

Graphene is a carbon based material and it has great potential of being utilized in various fields such as electronics, optics, and mechanics. In order to develop graphene-based logic systems, graphene field-effect transistor (GFET) has been extensively explored. GFET requires supporting devices, such as volatile memory, to function in an embedded logic system. As far as we understand, graphene has not been studied for volatile memory application, although several graphene non-volatile memories (GNVMs) have been reported. However, we think that these GNVM are unable to serve the logic system properly due to the very slow program/read speed. In this study, a GVM based on the GFET structure and using an engineered graphene channel is proposed. By manipulating the deposition condition, charge traps are introduced to graphene channel, which store charges temporarily, so as to enable volatile data storage for GFET. The proposed GVM shows satisfying performance in fast program/erase (P/E) and read speed. Moreover, this GVM has good compatibility with GFET in device fabrication process. This GVM can be designed to be dynamic random access memory (DRAM) in serving the logic systems application. We demonstrated GVM with the structure of FET. By manipulating the graphene synthesis process, we could engineer the charge trap density of graphene layer. In the range that our measurement system can support, we achieved a high performance of GVM in refresh (>10 ${\mu}s$) and retention time (~100 s). Because of high speed, when compared with other graphene based memory devices, GVM proposed in this study can be a strong contender for future electrical system applications.

• Korean Journal of Environmental Agriculture
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• v.29 no.4
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• pp.367-373
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• 2010

The study was established to compare fruit qualities and antioxidant compounds in 'Niitaka' pear (Pyrus pyriforia) trees grown in the organic and conventional farming systems. Fruits in the organic system appeared to have dark red color on the fruit surface. Fruit weight, soluble solids, acidity, firmness, and stone cells were not different between the farming systems. Organic fruits had a greater potassium concentration than the conventional fruits, but phosphorous, calcium, and magnesium concentrations in fruits were not different between the treatments. Peel, flesh, and juice parts in the organic fruits had greater phenolic compounds compared to the conventional fruits. Peel parts had much greater antioxidant compounds than the flesh parts, regardless of the treated-fruits. All fruits grown in the conventional and organic systems had a similar DPPH ($\alpha$, $\alpha$-diphenyl-$\beta$-picryl-hydrazyl) radical-scavenging activity in the peel, but flesh parts in organic fruits had a greater DPPH than the conventional fruits. Phenol and flavonoid compounds in the peel and flesh were positively related to the DPPH radical-scavenging activity. There were no significant differences for the nitrite scavenging activity in the peel and flesh parts between the treatments.

• Journal of Periodontal and Implant Science
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• v.36 no.3
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• pp.579-590
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• 2006

1. 연구배경 교원질 분해작용을 하는 호중구의 세포질 효소인 기질금속단백분해효소-8은 치주질환, 류마티스 관절염, 그리고 궤양결장염과 같은 염증성 질환에서 농도가 증가한다고 알려져 있다. 최근에는 A. actinomycetemcomitans의 leukotoxin이 사람호중구에서 기질금속단백분해효소-8의 분비를 유도하는 것이 보고되었다. 이 연구의 목적은 선천면역 체계에서 세포표면 항원무리14, Toll-like 수용기, 그리고 $NF-{\kappa}$ B경로를 통하여 A. actinomycetemcomitans의 지질다당질로 유도된 기질금속단백분해효소-8의 분비 여부와 세포기전을 알아보고자 하였다. 2. 연구재료 및 방법 건강한 개인 제공자(남자 13명, 여자 3명)로부터 얻은 개개인의 20ml 말초혈액을 제조사의 지침에 따라 호중구를 추출한 후 항세포표면 항원무리14와 함께 $4^{\circ}C$에서 30분간 전배양 한 후, $37^{\circ}C$에서 9시간 동안 배양시켰다. 추출한 호중구에 Toll-like 수용기 억제제 또는 $NF-{\kappa}$ B억제제인 TPCK를 첨가한 후 $37^{\circ}C$에서 1시간 동안 전배양하고 $37^{\circ}C$에서 9시간 동안 배양시켰다. 호중구에 세포뼈대 억제제인 cholchicine, nocodazole, demecolcine, 그리고 cytochalasin B를 A. actinomycetemcomitans의 지질다당질과 함께 $37^{\circ}C$에서 9시간 동안 배양시켰다. 기질금속단백분해효소-8 분비량은 효소면역측정법을 통해 결정하였다. 통계처리는 일원배치 분산분석법을 이용하였다(p<0.05). 3. 결과 A. actinomycetemcomitans 지질다당질은 기질금속단백분해효소-8의 분비를 증가시켰다. 기질금속단백분해효소-8의 분비는 항세포표면 항원무리14에 의해서 억제되었지만, 항 Toll-like 수용기2, 항 Toll-like 수용기4 항체는 억제시키지 못했다. $NF-{\kappa}$ B 억제제는 A. actinomycetemcomitans의 지질다당질로 유도된 $NF-{\kappa}$ B 결합 활성도와 기질금속단백분해효소-8 분비를 억제하였다. 미세섬유 중합반응 억제제는 A. actinomycetemcomitans의 지질다당질로 유도된 기질금속단백분해효소-8의 분비를 억제시켰으나, 미세관 중합반응억제제는 억제시키지 못했다. 4. 결론 위의 연구결과를 종합하여 볼 때, 기질금속단백분해효소-8은 A. actinomycetemcomitans의 지질다당질로 유도되며, 세포표면 항원무리-$NF-{\kappa}$ B 경로를 통하여 분비되고, 이 분비 과정은 미세섬유 계통이 관여하는 것으로 보인다.

• Journal of Ginseng Research
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• v.38 no.4
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• pp.256-263
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• 2014

Background: Korean Red Ginseng (KRG) is known to have antianxiety properties. This study was conducted to investigate the anxiolytic effects of KRG extract (KRGE) during ethanol withdrawal (EW) and the involvement of the mesoamygdaloid dopamine (DA) system in it. Methods: Rats were treated with 3 g/kg/d of ethanol for 28 d, and subjected to 3 d of withdrawal. During EW, KRGE (20 mg/kg/d or 60 mg/kg/d, p.o.) was given to rats once/d for 3 d. Thirty min after the final dose of KRGE, anxiety-like behavior was evaluated in an elevated plus maze (EPM), and plasma corticosterone (CORT) levels were determined by a radioimmunoassay (RIA). In addition, concentrations of DA and 3,4-dihydroxyphenylacetic acid (DOPAC) in the central nucleus of the amygdala (CeA) were also measured by high performance liquid chromatography (HPLC). Results: The EPM test and RIA revealed KRGE inhibited anxiety-like behavior and the over secretion of plasma CORT during EW. Furthermore, the behavioral effect was blocked by a selective DA D2 receptor (D2R) antagonist (eticlopride) but not by a selective DA D1 receptor (D1R) antagonist (SCH23390). HPLC analyses showed KRGE reversed EW-induced decreases of DA and DOPAC in a dose-dependent way. Additionally, Western blotting and real-time polymerase chain reaction (PCR) assays showed that KRGE prevented the EW-induced reductions in tyrosine hydroxylase (TH) protein expression in the CeA and TH mRNA expression in the ventral tegmental area (VTA). Conclusion: These results suggest that KRGE has anxiolytic effects during EW by improving the mesoamygdaloid DA system.