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Kinetic Studies on Halogen Exchange of Substituted Benzenesulfonylbromides

  • Kim, Jaerok
    • Nuclear Engineering and Technology
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    • v.5 no.4
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    • pp.321-333
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    • 1973
  • The rates and activation parameters for the halide exchange reactions of substituted benzenesulfonylbromides (R-C$_{6}$H$_4$SO$_2$Br, R=p-MeO, p-$CH_3$, p-H, p-NO$_2$) in dry acetone at two temperatures were determined. It was found that the nucleophilicity order of Cl->I-$\geq$Br- for strong electron withdrawing-, and mild electron donating group, and of I-$\geq$Cl->Br- for strong electron donating group, Hammett plots showed slightly convoked characteristics which is similar to the plots of substituted benzenesulfonylchlorides, but contrary to the concaved nature for the halide exchange reactions of substituted benzyl chlorides. The rate of halogen exchange between benzenesulfonylbromide and lithium bromide decreased in the order of solvent : ($CH_3$)$_2$CO>$CH_3$CN》MeOH. The rates and activation parameters were also compared with those already known in the substituted benzenesulfonylchlorides. Theses were explained in terms of the structural properties of the transition state, and discussed the reaction mechanisms.s.

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Effects of Gamma Radiation and Methyl Bromide Fumigation on Physiological and Chemical Quality of Apples (감마선과 Methyl Bromide 처리가 사과의 생리화학적 품질에 미치는 영향)

  • 강호진;정헌식;조덕조;변명우;최성진;최종욱;권중호
    • Food Science and Preservation
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    • v.10 no.3
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    • pp.381-387
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    • 2003
  • ‘Fuji’ apples were treated by gamma irradiation (0 - 3 kGy) or methyl bromide fumigation at commercial conditions (MeBr, 26 g/kg, 4 hr) for quarantine purposes at two different treatment timing after harvest and stored under air at 0$^{\circ}C$ for 4 months. Associated with the treatment timing of irradiation or fumigation, after 40 days of storage at 0$^{\circ}C$ following harvest was more adequate than immediately after harvest in keeping qualities of stored apples. However, more than 2 kGy irradiation and MeBr fumigation were detrimental to physiological and chemical qualities of the fruits. These results show that less than 1 kGy irradiation at the delayed timing has a possibility to be applied as a quarantine procedure without significant changes in the quality of apples.

Upregulaton of Bradykinin Receptor Mediated by Nucleoside Diphosphate Kinase and Flagellin from Pseudomonas aeruginosa (Bradykinin Receptor의 발현에 미치는 녹농균유래 Nucleoside Diphosphate Kinase 및 Flagellin의 효과)

  • Kim, Yong-Jae;Shin, Hee-Sung;Jin, Shouguang;Ha, Un-Hwan
    • Korean Journal of Microbiology
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    • v.50 no.4
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    • pp.281-284
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    • 2014
  • Immune defense responses against Pseudomonas aeruginosa infection play an important role in maintaining homeostasis in the human body. Previously, we reported that expression of the bradykinin receptor (BR) is induced in response to P. aeruginosa infection. However, the factors responsible for the induction was uncertain. Here, we found that the type III secretion system (T3SS) is responsible for the induction of BR expression, and nucleoside diphosphate kinase (Ndk), as a novel T3SS effector, mediates the upregulation. The Ndk-mediated expression of BR was not induced by fliC mutant treatment, indicating the involvement of flagellin, one of the well-known pathogen-associated molecular patterns (PAMPs). Taken together, this study demonstrated that Ndk cooperates with flagella in the development of defense responses against P. aeruginosa infection.

Effects of Brown Rice Extract Treated with Lactobacillus sakei Wikim001 on Osteoblast Differentiation and Osteoclast Formation

  • Kang, Miran;Song, Jung-Hee;Park, Sung-Hee;Lee, Jong-Hee;Park, Hae Woong;Kim, Tae-Woon
    • Preventive Nutrition and Food Science
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    • v.19 no.4
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    • pp.353-357
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    • 2014
  • Phytic acid (myo-inositol hexakisphosphate) or phytate is considered an anti-nutrient due to the formation of precipitated complexes that strongly reduces the absorption of essential dietary minerals. In this study, brown rice with reduced phytate was made by inoculation with Lactobacillus sakei Wikim001 having high phytase activity. The effects of brown rice extract treated with L. sakei Wikim001 (BR-WK) on osteoblast differentiation and osteoclast formation were investigated. The proliferation of SaOS-2 cells was measured by the MTT assay. Treatment with BR-WK increased cell proliferation by 136% at a concentration of $100{\mu}g/mL$. The Alkaline phosphate activity in SaOS-2 cells was 129% higher when BR-WK was processed at a concentration of $100{\mu}g/mL$. The proliferation of bone marrow macrophages decreased by nearly 60% in response to treatment with BR-WK. In addition, BR-WK reduced the number of tartrate-resistant acid phosphatase-positive ($TRAP^+$) multinucleated cells from bone marrow macrophages. These results indicate that BR-WK stimulates bone formation through its positive action on osteoblast differentiation and function and furthermore, decreases osteoclast differentiation.

Expression of Anti-breast Cancer Monoclonal Antibody in Transgenic Plant

  • Kim, Deuk-Su;Shao, Yingxue;Lee, Jeong-Hwan;Yoon, Joon-Sik;Park, Se-Ra;Choo, Young-Kug;Hwang, Kyung-A;Ko, Ki-Sung
    • Korean Journal of Environmental Agriculture
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    • v.30 no.4
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    • pp.390-394
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    • 2011
  • BACKGROUND: Plant expression system for mass production of recombinant proteins has several advantages over other existing expression systems with economical and safety issues. Breast cancer is a cancer originating from breast tissue and comprises almost 25% of all cancers in women world widely. Lewis-Y antigen is difucosylated oligosaccharide and is carried by glycoconjugates at cancer cell surface. In this study, the anti-breast cancer mAb BR55, which recognizes the epitope Lewis-Y, was expressed in the plant expression system. METHODS AND RESULTS: We have developed plant system for production of mAb BR55 with or without KDEL (the ER retention signal). This ER retention signal was attached to C-terminus of protein to help retain the recombinant glycoprotein carrying oligomannose glycans and enhance glycoprotein accumulation. PCR analysis was performed and confirmed the presence of recombinant genes. Western blot validated that the recombinant proteins mAb BR55 with or without KDEL were expressed in transgenic plants, moreover, the expression level of the mAb BR55 with KDEL was higher compared to the mAb BR55 without KDEL. CONCLUSION: These results indicate that KDEL fusion is a good way to produce proteins and plant can be an ideal expression system to obtain proteins and enhance accumulation of proteins.

Cloning and Transctiption of Excherichia coli Cell Division Gene, sep (E. coli 세포분열 유전자 sep의 Cloning 및 Transcription에 관한 연구)

  • ;Walker, James R.
    • Korean Journal of Microbiology
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    • v.22 no.4
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    • pp.235-242
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    • 1984
  • Sep gene, which is one of the cell division genes coding for penicillin binding protein 3 was subcloned from ${\lambda}607sep^{+2}$ to plasmid pBR322. which has a strong promotor such as lac UV5(lacP). It was confirmed that the sep gene cloned to pLJ3 was in the proper orientation for expressionfrom lactose promotor. To analyze the expression efficiency of sep gene within the plasmids newly constructed, sep mRNA was assated by using ${\lambda$\mid$\;607sep^{+2}$ DNA as a probe. Sep mRNA level was increased 25 times in the cells carrying sep gene cloned to pBR322 compared to E. coli C600 which has wild type sep gene within the chromosome instead of plasmed. Furthermore, the cells carrying sep gene cloned to pLJ3 derected the synthesis of about 50 times as much sep mRNA as did cells carrying sep gene cloned to pBR 322, representing that the sep gene was successfully cloned to pLJ3.

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Expression of a Glutathione Reductase from Brassica rapa subsp. pekinensis Enhanced Cellular Redox Homeostasis by Modulating Antioxidant Proteins in Escherichia coli

  • Kim, Il-Sup;Shin, Sun-Young;Kim, Young-Saeng;Kim, Hyun-Young;Yoon, Ho-Sung
    • Molecules and Cells
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    • v.28 no.5
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    • pp.479-487
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    • 2009
  • Glutathione reductase (GR) is an enzyme that recycles a key cellular antioxidant molecule glutathione (GSH) from its oxidized form (GSSG) thus maintaining cellular redox homeostasis. A recombinant plasmid to overexpress a GR of Brassica rapa subsp. pekinensis (BrGR) in E. coli BL21 (DE3) was constructed using an expression vector pKM260. Expression of the introduced gene was confirmed by semi-quantitative RT-PCR, immunoblotting and enzyme assays. Purification of the BrGR protein was performed by IMAC method and indicated that the BrGR was a dimmer. The BrGR required NADPH as a cofactor and specific activity was approximately 458 U. The BrGR-expressing E. coli cells showed increased GR activity and tolerance to $H_2O_2$, menadione, and heavy metal ($CdCl_2$, $ZnCl_2$ and $AlCl_2$)-mediated growth inhibition. The ectopic expression of BrGR provoked the co-regulation of a variety of antioxidant enzymes including catalase, superoxide dismutase, glutathione peroxidase, and glucose-6-phosphate dehydrogenase. Consequently, the transformed cells showed decreased hydroperoxide levels when exposed to stressful conditions. A proteomic analysis demonstrated the higher level of induction of proteins involved in glycolysis, detoxification/oxidative stress response, protein folding, transport/binding proteins, cell envelope/porins, and protein translation and modification when exposed to $H_2O_2$ stress. Taken together, these results indicate that the plant GR protein is functional in a cooperative way in the E. coli system to protect cells against oxidative stress.

Effects of Protein Kinase Inhibitors on Melanin Production in B16 Melanoma Cells Stimulated via Cyclic AMP-dependent Pathway (B16 Melanoma 세포에서 Protein Kinase 억제제들이 Cyclic AMP 경로를 통한 멜라닌 생성에 미치는 영향)

  • 차상복;조남영;윤미연;임혜원;김경원;박영미;이지윤;이진희;김창종
    • YAKHAK HOEJI
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    • v.47 no.1
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    • pp.31-36
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    • 2003
  • To investigate the effect of protein kinase on melanin production via cAMP-dependent pathway, we measured the melanin amount and tyrosinase activity in B16 melanoma cells stimulated by alpha-melanocyte stimulating hormone (MSH), forskolin and 8-Br-cAMP. MSH, forskolin and 8-Br-cAMP significantly increased both melanin production and tyrosinase activity in B16 cells. Melanin production and tyrosinase activity by MSH are significantly inhibited by cyclic AMP-dependent protein kinase inhibitor (KT5720) and protein kinase C down-regulation treated with PMA. Bisindolmaleimide (1$\mu$M), protein kinase C inhibitor, significantly inhibited melanin production and tyrosinase activity stimulated by MSH, forskolin and 8-Br-cAMP with the following order of potency: MSH>forskolin>8-Br-cAMP. Tyrosine kinase inhibitor, genistein and DHC, significantly inhibited both, but the inhibitory effect was more potent in 8-Br-cAMP-stimulated B16 cells than MSH-stimulated cells. NFkB inhibitor (parthenolide) significantly inhibited melanin production and tyrosinase activity. Neither melanin production nor tyrosinase activity induced by MSH, forskolin and 8-Br-cAMP were affected by KN-62 (calmodulin-dependent protein kinase II inhibitor), PD098059 (mitogen-activated protein kinase inhibitor, MAPKK) and worthmannin (phosphatidylinositol 3-kinase inhibitor). These results suggest that both protein kinase C and tyrosine kinase are involved in melanin production by cyclic AMP-dependent pathway and NFkB pathway may play an important role in cyclic AMP-dependent melanin production in B16 melanoma cells.

Consideration of the Exercise position for Facilitating Gluteus Medius Maximally in Normal Adults

  • Park, Sung Jin;Park, Ji Won;Kwon, Yonghyun
    • The Journal of Korean Physical Therapy
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    • v.31 no.1
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    • pp.62-66
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    • 2019
  • Purpose: This study examined the most efficient exercise position to activate the gluteus medius (GM) and tensor fascia latae (TFL) in hip abduction in side-lying (HA-SL), clam in side-lying (CL-SL), and sling bridging in side-lying (SB-SL), which are the most representative GM exercises. Methods: Twenty-four healthy male adults aged from 20 to 40 years, whose body mass index was under 25, participated in this experiment. While all participants conducted three different positions with a counterbalanced manner, such as in AB, CL, and BR, activation of the GM and TFL was measured using 8-channel wireless EMG. Exercise was performed for 10 seconds three times in total with a five minute-break session. Results: Significant differences in GM and TFL activation were observed among the three positions (p<0.05). The highest activation of 60.69 was observed in BR followed in order by 46.03 and 12.92 in HA-SL and CL, respectively. TFL activation in HA-SL was 42.01, followed in order by 35.98 and 14.01 in BR and CL, respectively. On the other hand, there was no significant difference in TFL muscle activation between BR and HA-SL. Conclusion: These findings suggest that both BR and HA-SL in GM can be done selectively. CL has remarkably low muscle activation in GM and TFL, which makes it less valuable in GM and TFL exercise. In conclusion, selective BR and HA-SL exercise should be applied to maximally and effectively activate the GM.

Synthesis of Alkylidyne Complexes of Br$(CO)_2(tmeda)M{\equiv}CC_{6}H_{4}Me$ (M = Cr, Mo, W). Crystal Structure of Br$(CO)_2(tmeda)M{\equiv}CC_{6}H_{4}Me$

  • Park, Joon T.;Cho, Jeong-Ju;Suh, Il-Hwan;Lee, Jin-Ho;Lim, Sung-Su;Ryu, Bo-Young
    • Bulletin of the Korean Chemical Society
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    • v.14 no.2
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    • pp.266-271
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    • 1993
  • The reaction of $(CO_5$)M=C(OMe)Tol (M=Cr, Mo, W and $Tol=p-C_6H_4Me)$ and $BBr_3$ followed by treatment with tetramethylethylenediamine (TMEDA) yields a mixture of two diastereomers, trans, $cis-Br(CO)_2(tmeda)M{\equiv}$CTol [M=Cr(1a), Mo(2a), W(3a)] and cis, $trans-Br(CO)_2(tmeda)M{\equiv}$CTol [M=Cr(1b), Mo(2b), W(3b)], respectively. These compounds have been isolated as crystalline solids and characterized by spectroscopic (infrared, mass, $^1H$ and $^{13}C-NMR)$ data. The trans, cis-Br(CO)2(tmeda)Cr${\equiv}$CTol (1a), has been examine via a single crystal X-ray diffraction study : $BrCrO_2N_2C_{16}H_{23}$, Mr=407.27, triclinic, $P{\bar{1}},\;a=12.792(2),\;b=13.400(5),\;c= 11.645(4)\;{\AA},\;{\alpha}=101.26(2)^{\circ},\;{\beta}=103.04(2)^{\circ},\;{\gamma}=91.88(2)^{\circ},\;{\nu}=1907(1){\AA}^3,\;Z=2,\;{\rho}(calcd)=1.418\;gcm^{-3},\;{\lambda}(MoK{\alpha})=0.71069\;{\AA},\;{\mu}=26.25 cm^{-1},\;F(000)=831.97,\;T=295K,\;R=0.0977$ for 1332 significant reflections $[F_0>5{\sigma}(F_0)]$. There are two essentially equivalent molecules in the crystallographic asymmetric unit. Each molecule is octahedral with the bromide ligand trans to the alkylidyne carbon, the two cis-carbonyl ligands, and the bidentate TMEDA ligand.