• Title/Summary/Keyword: $S_N2-S_N2'$ Reaction

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Quality Improvement of Rainbow Trout with Pigments and Enzymatic Hydrolysates of Ascidian (Halocynthia roretzi) Tunic 1. Chemical Specificity of Ascidian Tunic and Its Hydrolysates (우렁쉥이 껍질의 색소 및 효소 가수분해물을 이용한 무지개 송어의 품질 향상 1. 우렁쉥이 껍질 및 효소 가수분해물의 화학적 특성)

  • CHOI Byeong-Dae;KANG Seok-Joong;LEE Kang-Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.29 no.3
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    • pp.345-356
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    • 1996
  • Properties of enzymatic hydrolysates from ascidian tunic were assessed on supernatant ratio, solid yields and solid concentration. The concentartion of solid and yields in the extracts were increased as the enzyme concentration raised from $100\;{\mu}l\;to\;1000{\mu}l$ during the extraction period. The optima concentration and reaction time of each enzyme on digestion were $400\;{\mu}l$ 60 minutes, through treated with Duncan's multiple test. The percent of yields of solid, protein and carotenoids for 60 minutes extraction at $400\;{\mu}l$ were $32.32\%,\;1.34\%\;and\;74.60\;mg\%$, respectively, in Viscozyme systems. The extracts were composed with many kinds of carbohydrates such as arabinose, ribose, xylose, galactose, glucose, N-acetyl-D-galactosamine, and N-acetyl-D-glucosamine. Aspartic and glutamic arid were noted as predominant amino acids in all parts. Amino acid profiles of various ascidian tunic part were similiar to each other, but most of essential amino acids content of inter coat was higher than that of root and tunic (body). About sixty six fatty acids components were observed, and their distribution among neutral and polar lipids was compared. The main fatty acids were found to be 14:0, 16:0, 16:1n7, 18:0, 18:1n9, 18:1n7, 18:2n6, 20:5n3, and 22:6n3.

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Upregulation of Connexin43 Expression in Mitral Valves in a Rabbit Model of Hypercholesterolemia (고콜레스테롤혈증을 유발한 토끼의 승모판막에서 Connexin43 발현의 증가)

  • Kwon, Jong-Bum;Park, Chan-Beom;Sa, Young-Jo;Kim, Young-Du;Moon, Seok-Whan;Kim, Chi-Kyung
    • Journal of Chest Surgery
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    • v.43 no.4
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    • pp.356-363
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    • 2010
  • Background: Connexin 43-mediated gap junctional communication plays an important role in atherosclerosis. Numerous studies have demonstrated a correlation between mitral valve annular calcification and atherosclerotic disease. However, the relevance of connexin 43 to mitral valve disease remains unclear. We hypothesized that the mechanism contributing to mitral valve disease is associated with alterations in cell-to-cell communication mediated by changes in Connexin 43 expression. Material and Method: Twenty male New Zealand rabbits were divided into two groups: animals in group 1 (n=10) were fed a normal chow diet, whilst those in group 2 (n=10) received a diet containing 1% cholesterol for 12 weeks. After sacrificing the animals, the mitral valves were excised and analyzed with immunohistochemical staining and Real-time Reverse Transcriptase polymerase chain reaction (real time RT-PCR). Result: Myofibroblasts and macrophages were found concentrated within the endothelial layer on the ventricular side of the leaflet in the cholesterol diet group. Immunohistochemial staining showed elevated expression of connexin43 in the cholesterol diet group. Real-time RT-PCR revealed increased connexin43 mRNA levels in mitral valves from hypercholesterolemic animals. Conclusion: Our finding that connexin43 expression is increased in mitral valves of hypercholesterolemic rabbits suggests that alterations in cell-to-cell communication via connexin43 containing gap junctions play a role in the development of mitral valve disease in hypercholesterolemia.

The Methane Reforming by $CO_2$ Using Pelletized Co-Ru-Zr-Si Catalyst (성형 Co-Ru-Zr-Si 촉매를 이용한 이산화탄소에 의한 메탄 리포밍)

  • Nam, Jeong-Kwang;Lee, Ji-Hye;Song, Sang-Hoon;Ahn, Hong-Chan;Chang, Tae-Sun;Suh, Jeong-Kwon;Kim, Seong-Bo
    • Applied Chemistry for Engineering
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    • v.23 no.2
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    • pp.176-182
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    • 2012
  • The methane dry reforming has received the considerable attention in recent years, mainly as an attractive route to produce synthesis gas (CO, $H_2$) from green-house gases ($CH_4$, $CO_2$) for resources. However, this process has not been commercialized due to the high temperature and catalyst deactivation. In this study, Co-Ru-Zr catalysts supported on $SiO_2$ were studied for the characterization of methane dry reforming reaction and the preliminary data for process development were achieved. The crystal structure of catalysts was measured by XRD, the surface area and pore size were analyzed by BET, and the element composition of catalyst were analyzed by EDS. Conversions of methane and carbon dioxide were analyzed by GC. In addition, reaction rate constants were obtained from the reaction kinetic study and the optimum catalyst size that does not affect mass transfer from reactants was also determined. The selected pellet-type catalyst maintained activation for 720 h at $850^{\circ}C$.

Purification and Properties of D-Xylose Isomerase from Lactococcus sp. JK-8 (Lactococcus sp. JK-8에서 생산된 D-Xylose isomerase의 정제와 특성에 관한 연구)

  • Jun, Hong-Ki;Kim, Suk-Young;Baik, Hyung-Suk
    • Journal of Life Science
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    • v.14 no.4
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    • pp.636-643
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    • 2004
  • D-Xylose isomerase produced by Lactococcus sp. JK-8, isolated from kimchi, was purified 17-fold of homogeneity, and its physicochemical properties were determined. Although the N-terminal amino acid sequence of D-xylose isomerase was analysed to Ala-Tyr-Phe-Asn-Asp-Ile-Ala-Pro-Ile-Lys, it was not similar to that of Lactobacillus enzyme. The molecular weight of the purified enzyme was estimated to be 180 kDa by gel filtration, 45 kDa by SDS-PAGE and the enzyme was homotetramer. The optimum pH of the enzyme was around 7 and stable between pH 6 and 8. The optimum reaction temperature was 7$0^{\circ}C$ and stable up to 7$0^{\circ}C$ in the presence of 1 mM $Mn^{2+}$. Like other D-xylose isomerases, this enzyme required divalent cation, such as $Mg^{2+}$, $Co^{2+}$, or $Mn^{2+}$ for the activity and thermostability. $Mn^{2+}$was the best activator. Substrate specificity studies showed that this enzyme was highly active on D-xylose. The enzyme had an isoelectric point of 4.8, and fm values for D-xylose was 5.9 mM.

Unusual Allosteric Property of L-alanine Dehydrogenase from Bacillus subtilis

  • Kim, Soo-Ja;Lee, Woo-Yiel;Kim, Kwang-Hyun
    • BMB Reports
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    • v.31 no.1
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    • pp.25-30
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    • 1998
  • Kinetic studies of L-Alanine dehydrogenase from Bacillus subtilis-catalyzed reactions in the presence of $Zn^{2+}$ were carried out. The substrate (L-alanine) saturation curve is hyperbolic in the absence of the metal ion but it becomes sigmoidal when $Zn^{2+}$ is added to the reaction mixture indicating the positive cooperative binding of the substrate in the presence of zinc ion. The cooperativity of substrate binding depends on the xinc ion concentration: the Hill coefficients ($n_H$) varied from 1.0 to 1.95 when the zinc ion concentration varied from 0 to $60\;{\mu}m$. The inhibition of AlaDH by $Zn^{2+}$ is reversible and noncompetitive with respect to $NAD^+$ ($K_i\;=\;5.28{\times}10^{-5}\;M$). $Zn^{2+}$ itself binds to AlaDH with positive cooperativity and the cooperativity is independent of substrate concentration. The Hill coefficients of substrate biding in the presence of $Zn^{2+}$ are not affected by the enzyme concentration indicating that $Zn^{2+}$ binding does not change the polymerization-depolymerization equilibria of the enzyme. Among other metal ions, $Zn^{2+}$ appears to be a specific reversible inhibitor inducing conformational change through the intersubunit interaction. These results indicate that $Zn^{2+}$ is an allosteric competitive inhibitor and substrate being a non-cooperative per se, excludes the $Zn^{2+}$ from its binding site and thus exhibits positive cooperativity. The allosteric mechanism of AlaDh from Bacillus subtilis is consistent with both MWC and Koshland's allosteric model.

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Expression of Human p53 Gene as Glutathione S-transferase Fusion Proteins in Escherichia coli (사람의 p53 유전자와 Glutathione S-Transferase와의 융합 단백질의 대장균에서의 발현)

  • 오상진
    • Korean Journal of Microbiology
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    • v.31 no.4
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    • pp.279-285
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    • 1993
  • Alterations of the p53 gene arc among the most frequent genetic changes in human cancer and often result in increased levels of p53 protein within the malignant cells. Detection of accumulated p53 protein can be a useful prognostic tool in human cancer. In order to make polyclonal antibodies for immunohistochemical screening. human p53 gene was expressed in E. coli in the form of GST (glutathione S-transfi.:rase) fusion proteins. Two p53 gene fragments. which were N('()I small fragment encoding amino acid residues of 1-151-: and Ncol large fragment of 159-393. were subeloned into the unique BamHI site present within the pGEX-2T vector using BamHI linker and recombinant plasmids pGTNS and pGTNL were constructed. respectively. The p53 cDNA fragment (from pC53-$SN_3$,) encoding amino acid 38-145 (proline at residue 72) was amplified by polymerase chain reaction(PCR). The amplified DNA was digested with BamHI and Prull and inserted into the BamHI-Smal sites of pG EX-2T and recombinant plasmid pGTBP was constructed. After IPTG induction of these plasmids for 4 hours. fusion proteins were purified from E. coli extracts with glutathione Sepharose beads. The bound proteins were resolved by 10% SDS-polyacrylamide gel electrophoresis and the molecular weights were 54 kDa. 53 kDa and 40 kDa. respectively. Approximately one milligram of fusion proteins were purified from 1 -liter cultures.

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Development of a PCR Assay for Detection of the Protozoan Parasite Perkinsus (PCR 기법을 이용한 바지락포자충 Perkinsus 진단 기술개발)

  • 박경일;박영미;이제희;최광식
    • Korean Journal of Environmental Biology
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    • v.20 no.1
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    • pp.109-109
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    • 2002
  • Detection of protozoan parasites Perkinsus sp. and P. atlanticus was developed in this study using a specific polymerase chain reaction (PCR) to diagnose the presence of those organisms that causes extensive mortalities of marine shellfishes. The PCR was conducted together with fluid thioglycollate medium (FTM) method and 2 M NaOH lysis method. For the test, Manila clams, Ruditapes philippinarum, were collected from four coastal locations in Korea including Wando Island, Gimnyeong, Sungsan and Sogwipo in Jeju. In addition, trophozites of Perkinsus sp. cultivated in vitro and the granular ark clam, Tegillarca granosa, taken from Gangjin on the south coast of Korea, were used as positive and negative controls, respectively. Expected DNA bands were detected in the samples from Wando Island, Sungsan and the in vitro cultured Perkinsus sp. when the probes specific for the genus Perkinsus and P. atlanticus were used. The samples were also positively diagnosed by the FTM and 2 M NaOH methods. In contrast, the Manila clams from Gimnyeong and Sogwipo, and the granular arks clams from Gangjin showed no detectable signs of infection with the PCR, the FTM method and the 2 M NaOH lysis method. On the other hand, being amplified by p. atlanticus specific primer, it is suggested that the protozoan parasite Perkinsus sp. found in the Korean Manila clam is P. atlanticus. Finally the PCR- based assay developed in the present study can be used in detection of Perkinsus infection and discrimination of Peykinsus species in quarantine stations or laboratories due to the high sensitivity and specificity as well as its rapid detection.

Changes in Postural Deviation Caused by the Pain Area (통증위치에 따른 자세 치우침의 차이비교)

  • Bang, Sang-Boon;Joung, Ho-Bal
    • Journal of Korean Physical Therapy Science
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    • v.9 no.3
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    • pp.97-106
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    • 2002
  • Purpose. This study was tried to compare the effect of the change in postural deviation caused by the pain side Subjects and Methods. Inpatients and outpatients (n=71) were selected from I hospital who have a musculoskeletal low back pain and shoulder pain without any history of the central nervous system (CNS) lesions, orthopaedic problems of the both lower extremities, or the vestibular and the visual default. For the control group, normal and healthy subjects (n=30) were selected without any history of weight bearing disorders. the weight bearing was rated by the computerized force plate. Results. 1) Postural deviation was not significant difference between patients and control group(p<0.01). But postural deviation in patients was more pronounced than control group. 2) There was significant difference of postural deviation between in patients according to the pain side(p<0.01). When the pain side was on the left side, postural deviation tended to the right. When the pain side was on the right side and vertebral body, postural deviation tended to the left. 3) There was no significant difference of postural deviation between regional pain in shoulder and regional pain in low back(p<0.01). Discussions and Conclusion. As a result, the pain, for sure, affected the good posture and its keeping process directly or/and indirectly. Therefore, as the postural deviation increases, the additional energy consumption increased by the works of the muscles to keep the good posture. Preponderated postural deviation, furthermore, could load too much to the musculoskeletal system, leading to increase the pain. The postural deviation, a result of the pain, can cause a secondary deformity of the distal area as a compensatory reaction, and this compensation actually become a cause of the musculoskeletal symptom back in a cycle. Therefore, the appropriate treatment of the musculoskeletal problem and the education of the posture correction should be given to decrease the pain, preventing the secondary deformities, and increasing muscle energy efficiency of the posture remaining muscles.

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Quantitative and Rapid Analysis of Transglutaminase Activity Using Protein Arrays in Mammalian Cells

  • Kwon, Mi-Hye;Jung, Jae-Wan;Jung, Se-Hui;Park, Jin-Young;Kim, Young-Myeong;Ha, Kwon-Soo
    • Molecules and Cells
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    • v.27 no.3
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    • pp.337-343
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    • 2009
  • We developed a novel on-chip activity assay using protein arrays for quantitative and rapid analysis of transglutaminase activity in mammalian cells. Transglutaminases are a family of $Ca^{2+}$-dependent enzymes involved in cell regulation as well as human diseases such as neurodegenerative disorders, inflammatory diseases and tumor progression. We fabricated the protein arrays by immobilizing N,N'-dimethylcasein (a substrate) on the amine surface of the arrays. We initiated transamidating reaction on the protein arrays and determined the transglutaminase activity by analyzing the fluorescence intensity of biotinylated casein. The on-chip transglutaminase activity assay was proved to be much more sensitive than the $[^3H]putrescine$-incorporation assay. We successfully applied the on-chip assay to a rapid and quantitative analysis of the transglutaminase activity in all-trans retinoic acid-treated NIH 3T3 and SH-SY5Y cells. In addition, the on-chip transglutaminase activity assay was sufficiently sensitive to determine the transglutaminase activity in eleven mammalian cell lines. Thus, this novel on-chip transglutaminase activity assay was confirmed to be a sensitive and high-throughput approach to investigating the roles of transglutaminase in cellular signaling, and, moreover, it is likely to have a strong potential for monitoring human diseases.

Isolation and Analysis of Micro-Regions Having Possibly Higher Tc in Oxide Superconductors (산화물계 초전도체의 고변이 송도부근의 곡출과 이의 성분 분석에 관한 연구)

  • 이규용
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.25 no.3
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    • pp.143-153
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    • 1989
  • In conclusion, a high-Tc superconducting YBa sub(2) Cu sub(3) O sub(y) phase with zero resistance at about 90K was successfully prepared by nitrate solution method with densed micro structure. The result of the EDAX analysis on the isolated particles using the microscopic meissner effect showed that the particles were isolated at higher temperature due to the differences in O vacances rather than the differences in chemical compositions. The composition of the isolated particles were almost identical to the starting compositions on the samples prepared by the solid reaction and nitrate solution method but the Ba-rich composition were seen in the coprecipitated sample. The isolation process on Bi system was not successful due to the weak dimagnetism even though its high Tc above the liquid nitrogen temperature.

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