• Title/Summary/Keyword: Korean binding

Search Result 7,376, Processing Time 0.051 seconds

Partial Oxidation of Methane to $H_2$ Over Pd/Ti-SPK and Pd/Zr-SPK Catalysts and Characterization (Pd/Ti-SPK과 Pd/Zr-SPK 촉매상에서 수소 생산을 위한 메탄의 부분산화반응과 촉매의 특성화)

  • Seo, Ho-Joon;Kang, Ung-Il
    • Applied Chemistry for Engineering
    • /
    • v.21 no.6
    • /
    • pp.648-652
    • /
    • 2010
  • Catalytic activities of the partial oxidation of methane (POM) to hydrogen were investigated over Pd(5)/Ti-SPK and Pd(5)/Zr-SPK in a fixed bed flow reactor (FBFR) under atmosphere, and the catalysts were characterized by BET, XPS, XRD. The BET surface areas, pore volume and pore width of Horvath-Kawaze, micro pore area and volume of t-plot of Pd(5)/Ti-SPK and Pd(5)/Zr-SPK were $284m^2/g$, $0.233cm^3/g$, 3.9 nm, $30m^2/g$, $0.015cm^3/g$ and $396m^2/g$, $0.324cm^3/g$, 3.7nm, $119m^2/g$, $0.055cm^3/g$, repectively. The nitrogen adsorption isotherms were type IV with hysteresis. XPS showed that Si 2p and O 1s core electronlevels of Ti-SPK and Zr-SPK substituted Ti and Zr shifted to slightly lower binding energies than SPK. The oxidation states of Pd on the surface of catalysts were $Pd^0$ and $Pd^{+2}$. XRD patterns showed that crystal structures of fresh catalyst changed amorphous into crystal phase after reaction. The conversion and selectivity of POM to hydrogen over Pd(5)/Ti-SPK and Pd(5)/Zr-SPK were 77, 84% and 78, 72%, respectively, at 973 K, $CH_4/O_2$ = 2, GHSV = $8.4{\times}10^4mL/g_{cat}{\cdot}h$ and were kept constant even after 3 days in stream. These results confirm superior activity, thermal stability, and physicochemical properties of catalyst in POM to hydrogen.

Renal Sympathetic Denervation Induces Acute Myocardial Inflammation through Activation of Caspase-1 and Interleukin-1β (교감신경절제술(RDN) 후 caspase-1과 interleukin-1β 활성화로 인해 유발된 염증성 급성심근손상)

  • Lee, Dong Won;Kim, Il Young;Kwak, Ihm Soo
    • Journal of Life Science
    • /
    • v.28 no.2
    • /
    • pp.240-246
    • /
    • 2018
  • Efferent and afferent sympathetic nerves are closely related to the development of hypertension and heart failure. Catheter-based renal sympathetic denervation (RDN) is implemented as a strategy to treat resistant hypertension. We investigated whether RDN procedure causes inflammatory damage on myocardium in the early phase of sympathetic denervation. Twenty-five female swine were divided into 3 groups: normal control (Normal, n=5), sham-operated control (Sham, n=5), and RDN groups (RDN, n=15). The RDN group was further subdivided into 3 subgroups according to the time of sacrifice: immediately (RDN-0, n=5), 1 week (RDN-1, n=5), and 2 weeks (RDN-2, n=5) after RDN. There were no significant changes in the clinical parameters between the normal control and sham-operated group using contrast-media. In the myocardium, inflammatory cytokines, $IL-1{\beta}$ and $TNF-{\alpha}$ increased at the first week, and then decreased at the second week after RDN. Anti-inflammatory cytokine, IL-10 increased immediately, and then decreased at the second week after RDN. Caspase-1 activity and apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC) expression increased immediately after RDN until the second week. However, nucleotide-binding oligomerization domain, leucine rich repeat and pyrin domain containing protein 3 (NLRP3) expression did not show any significant differences among the groups. The RDN can cause acute myocardial inflammation through activation of caspase-1 and $IL-1{\beta}$. We should pay attention to protecting against early inflammatory myocardial damage after RDN.

Differences in Structural Characteristics and Eu(III) Complexation for Molecular Size Fractionated Humic Acid (분자량별 분류에 따른 휴믹산의 구조적 특성 및 Eu(III)과의 착물 반응 특성 비교에 대한 연구)

  • Shin, Hyun-Sang;Rhee, Dong-Seok;Kang, Kihoon
    • Analytical Science and Technology
    • /
    • v.14 no.2
    • /
    • pp.159-166
    • /
    • 2001
  • A humic acid(HA, Aldrich Co) sample was subjected to ultrafiltration for molecular size fractionation and three fractions of different nominal size($F_1$: 1,000-10,000 daltons; $F_2$: 10,000-50,000 daltons; $F_3$: 100,000-300,000 daltons) were obtained. The structural characteristics of the size-fractionated HA were analyzed using their IR and solid state C-13 NMR spectral data, and the carboxylate group contents of the humic acids were determined using their pH titration data. The $^7F_0-{^5}D_0$ excitation spectra of Eu(III) complexes of the size-fractionated mgHA in aqueous solution were acquired($[Eu(III)]=1.0{\times}10^{-4}mol\;L^{-1}$, $(HA)=470-970mg\;L^{-1}$) at pH 5.0 using a pulsed tunable laser system, in which metal binding properties of the size-fractionated HA were elucidated and compared on another. Characterization of the IR and C-13 NMR spectral data indicated that the fraction($F_3$) with molecules of larger size were primarily aliphatic, while the fractions($F_1$, $F_2$) with smaller molecules of less than 50,000 daltons were predominantly aromatic. Titration data were consistent with an increase in the number of carboxylate groups per unit mass as molecular size became smaller. The $^7F_0-{^5}D_0$ excitation spectral data of Eu(III)-humate complexes showed that the peak maxima on these spectra were shifted toward lower energies with increasing molecular size of HA, indicating the higher degree of bindings of the Eu in the molecules of larger size. We also discussed the relationship of the lower energy shifts of the maximum peaks with increasing the molecular size of HA with the structural differences of the size-fractionated HA.

  • PDF

Allium hookeri Extract Improves Type 2 Diabetes Mellitus in C57BL/KSJ Db/db Obese Mouse via Regulation of Hepatic Lipogenesis and Glucose Metabolism (삼채 추출물의 인슐린 저항성 개선 효과 및 기전 탐색)

  • Kim, Ji-Soo;Heo, Jin-Sun;Choi, Jong-Won;Kim, Gun-Do;Sohn, Kie-Ho
    • Journal of Life Science
    • /
    • v.25 no.10
    • /
    • pp.1081-1090
    • /
    • 2015
  • Diabetes has been one of major health risks in industrialized countries. Allium hookeri is a wild herb distributed in India and Myanmar. The root of the plant has been used as food and medicine in Southeast Asia. We investigated Allium hookeri extract improves type 2 diabetes mellitus in C57BL/KSJ db/db obese mouse. C57BL/KSJ db/db obese mouse arise out of Type 2 diabetes and we treated Allium hookeri methanol extract 400 mg/kg (AH 400), 800 mg/kg (AH 800), positive control group (thiazolidinedine;TZDs) were administered orally for 8weeks. AH treated group normalized lipid enzyme system (triglyceride, total cholesterol, HDL-cholesterol and LDL-cholesterol) and serum glucose, HbA1c and plasma insulin level. AH treated group recovered β-cell damage by hyperglycemia and fatty liver disease. AH treated group significantly up regulated expression of Peroxisome proliferator-activated receptor gamma (PPAR-γ), pyruvate dehydrogenase kinase4 (PDK4), Sterol regulatory element-binding protein 1c (SREBP 1) and fork head box O1 (FOX 01) proteins in C57BL/KSJ db/db obese mouse liver. And we found that AH treated group decreased hepatic malondialdehyde formation in C57BL/KSJ db/db obese mouse liver. These results indicate that Allium hookeri methanol extract might be a potential anti-diabetic agent and could be useful in the treatment of type 2 diabetes mellitus.

The Significance of Registration Convention and its Future Challenges in Space Law (등록협약의 우주법상 의의와 미래과제에 관한 연구)

  • Kim, Han-Taek
    • The Korean Journal of Air & Space Law and Policy
    • /
    • v.35 no.2
    • /
    • pp.375-402
    • /
    • 2020
  • The adoption and entering into force of the Registration Convention was another achievement in expanding and strengthening the corpus iuris spatialis. It was the fourth treaty negotiated by the member states of the UNCOPUOS and it elaborates further Articles 5 and 8 of the Outer Space Treaty(OST). The Registration Convention also complements and strengthens the Article 11 of the OST, which stipulates an obligation of state parties to inform the UN Secretary-General of the nature, conduct, locations, and results of their space activities in order to promote international cooperation. The prevailing purposes of the Registration Convention is the clarification of "jurisdiction and control" as a comprehensive concept mentioned in Article 5 8 of the OST. In addition to its overriding objective, the Registration Convention also contributes to the promotion and the exploration and use of outer space for peaceful purposes. Establishing and maintaining a public register reduces the possibility of the existence of unidentified space objects and thereby lowers the risk such as, for example, putting the weapons of mass destruction secretly into orbit. And furthermore it could serve for a better space traffic management. The Registration Convention is a treaty established to implement Article 5 of OST for the rescue and return of astronaut in more detail. In this respect, if OST is a general law, the Registration Convention would be said to be in a special law. If two laws conflict the principle of lex specialis will be applied. Countries that have not joined the Registration Convention will have to follow the rules concerning the registration of paragraph 7 of the Declaration by the United Nations General Assembly resolution 1721 (X V I) in 1961. UN Resolution 1721 (XVI) is essentially non-binding, but appears to have evolved into the norm of customary international law requiring all States launching space objects into orbit or beyond to promptly provide information about their launchings for registration to the United Nations. However, the nature and scope of the information to be supplied is left to the discretion of the notifying State. The Registration Convention is a treaty created for compulsory registration of space objects by nations, but in reality it is a treaty that does not deviate from existing practice because it is based on voluntary registration. With the situation of dealing with new problems due to the commercialization and privatization of the space market, issues related to the definition of a 'space object', including matter of the registry state of new state that purchased space objects and space debris matter caused by the suspension of space objects launched by the registry state should be considered as matters when amendments, additional protocols or new Registration Convention are established. Also the question of registration of a flight vehicle in the commercial space market using a space vehicle traveling in a sub-orbital in a short time should be considered.

$17{\beta}$-Estradiol Regulates the Expression of Nesfatin-1/NUCB2 in Mouse Uterus ($17{\beta}$-Estradiol에 의한 생쥐 자궁 내 Nesfatin-1/NUCB2 발현 조절)

  • Kim, Jin-Hee;Lee, Kyoung-Ran;Kim, Hyeon-Kyeong;No, So-Hyeon;Yoo, Hye-Min;Moon, Chan-Il;Yang, Hyun-Won
    • Development and Reproduction
    • /
    • v.15 no.4
    • /
    • pp.349-357
    • /
    • 2011
  • Since nesfatin-1/NUCB2 involved in the control of appetite and energy metabolism was discovered for the first time in hypothalamus, many reports have shown its expression in various tissues. We also recently demonstrated that nesfatin-1/NUCB2 was expressed in the reproductive organs of mouse. However, no data exist on nesfatin-1/NUCB2 expression, regulation, and secretion in the uterus. Therefore, we examined the expression of nesfatin-1/NUCB2 in mouse uterus and the effects of PMSG and estrogen on its expression. NUCB2 mRNA expression in the uterus was determined by conventional and real-time PCR and nesfatin-1 protein expression was detected by western blotting. In immunohistochemistry staining, nesfatin-1 protein was localized at the epithelial cells of the uterine glands and endometrium. Nesfatin-1 protein binding sites were displayed at the epithelial cells of uterine glands and specific granulocytes including neutrophils. Additionally, to examine if the nesfatin-1/NUCB2 expression in the uterus is regulated by gonadotropin or estrogen, ovariectomized mice were treated with PMSG or $17{\beta}$-estradiol. The expression levels of NUCB2 mRNA in the uterus was significantly increased in the control mice after PMSG treatment, but not in the ovariectomized mice. In contrast, NUCB2 mRNA expression was dramatically increased in the ovariectomized mice after treatment with $17{\beta}$-estradiol. We report here for the first time that nesfatin-1/NUCB2 mRNA and protein express in the mouse uterus and its expression is regulated by estrogen secreted from the ovary, but not gonadotropin from the pituitary.

Anti-adipogenic Activity of Cortex ulmi pumilae Extract in 3T3-L1 Preadipocytes (유근피 추출물의 3T3-L1지방전구세포의 분화 억제 효능에 관한 연구)

  • Jeong, Hyun Young;Jin, Soojung;Nam, Soo Wan;Hyun, Sook Kyung;Kim, Sung Gu;Kim, Byung Woo;Kwon, Hyun Ju
    • Journal of Life Science
    • /
    • v.24 no.2
    • /
    • pp.137-147
    • /
    • 2014
  • Cortex ulmi pumilae, the cortex of Ulmus davidiana var. japonica, has been used in traditional folk medicine for its anti-inflammatory effect. Although its various bioactivities such as anti-inflammatory, anti-microbial, and anti-cancer, have been reported, the anti-adipogenic activity of cortex ulmi pumilae remains unclarified. In the present study, we investigated the effect of cortex ulmi pumilae extract on adipocyte differentiation in 3T3-L1 preadipocytes. Treatment with cortex ulmi pumilae extract significantly reduced the formation of lipid droplets and triglyceride content in a dose-dependent manner; this is associated with an inhibition of the adipogenic transcription factors, CCAAT/enhancer binding protein ${\alpha}$ ($C/EBP{\alpha}$), $C/EBP{\beta}$, and peroxisome proliferator-activated receptor ${\gamma}$ ($PPAR{\gamma}$). In addition, cortex ulmi pumilae extract treatment during the early stage of adipogenesis showed more efficient anti-adipogenic activity than treatment during other stages of adipogenesis. Cortex ulmi pumilae extract also inhibited cell proliferation and induced G1 arrest of 3T3-L1 cells in the early stage of adipogenesis. This was associated with upregulated expression of Cdk inhibitor p21 and downregulated expression of cyclin E and phospho-Rb, indicating that cortex ulmi pumilae extract blocks mitotic clonal expansion by cell cycle regulation. Taken together, these results suggest that cortex ulmi pumilae extract possesses anti-adipogenic activity through the inhibition of adipocyte differentiation by blocking mitotic clonal expansion.

Protein Engineering of Flavin-containing Monooxygenase from Corynebacterium glutamicum for Improved Production of Indigo and Indirubin (인디고와 인디루빈의 생산을 증대하기 위한 플라빈-함유 모노옥시게나제의 단백질공학)

  • Jung, Hye Sook;Jung, Hae Bin;Kim, Hee Sook;Kim, Chang Gyeom;Lee, Jin Ho
    • Journal of Life Science
    • /
    • v.28 no.6
    • /
    • pp.656-662
    • /
    • 2018
  • Flavin-containing monooxygenases from Corynebacterium (cFMOs) were mutagenized based on homology modeling to develop variants with an enhanced indigoid production capability. The four mutants, F170Y, A210G, A210S, and T326S, which fused to a maltose-binding protein (MBP), were constructed, and their biochemical properties were characterized. Of these, purified MBP-T326S required a higher concentration of exogenous FAD (100 mM) than the wild-type MBP-cFMO for optimal activity and showed a 3.8-fold increase in the $k_{cat}/K_m$ value at $100{\mu}M$ FAD compared to that of MBP-cFMO at $2{\mu}M$ FAD. The indole oxygenase activities of MBP-T326S decreased to 63-77% compared to that of the MBP-cFMO In addition, MBP-T326S displayed a very low level of futile NADPH oxidase activities (21-24%) in the absence of a substrate. Mutant proteins except for T326S displayed similar $K_m$ and increased $k_{cat}/K_m$ values compared to the wild-type. MBP-F170Y and -A210S mutants showed elevated indole oxygenase activity higher than 3.1- and 2.9-fold, respectively, in comparison with MBP-cFMO. When indigoid production was carried out in LB broth with 2.5 g/l of tryptophan, Escherichia coli expressing cFMO produced 684 mg/l of indigo and 104 mg/l of indirubin, while cells harboring T326S produced 1,040 mg/l of indigo and 112 mg/l of indirubin. The results indicate that the production of indigo was 13% higher when compared to a previous report in which an E. coli expressing FMO from Methylophaga produced 920 mg/l of indigo. The protein engineering of cFMO based on homology modeling provided a more rational strategy for developing indigoid-producing strains.

Natural killer cell activity in mice infected with Acanthamoeba culbertsoni (Acanthamoeba culbertsoni 감염에 있어 자연살세포의 활성)

  • Hyeon, Dong-Geun;Sin, Ju-Ok;Im, Gyeong-Il
    • Parasites, Hosts and Diseases
    • /
    • v.30 no.2
    • /
    • pp.101-112
    • /
    • 1992
  • The natural killer cell activity of splenocytes and TBC, active NK cells, recycling capacity of natural killer cells were observed by means of both the 51Cr-release cytotoxicity assay and single cell cytotoxicity assay against YAC-1. CSH/HeJ mice were infected intranasally with $1{\times}10^4{\;}or{\;}1{\times}10^5$ trophosoites of pathogenic Acanthamoeba culbertsoni. The infected mice showed mortality rate of 34% in $1{\times}10^4$ group and 65% in 1{\times}10^5 group, and mean survival time was $16.40{\pm}3.50$ {\;}and{\;}3.20{\pm}4.09$ days respectively. The cytotoxic activity of natural killer cells of the 2 groups was significantly higher than that of non-infected mice from the 12th hour to the 2nd day after infection, showing the highest on the first day. On the l0th day after infection, the cytotoxic activity of natural killer cells was significantly suppressed as compared with that of the control. There was no significant difference in NK cell cytotoxicity between two infected groups. The targetbinding capacity and active NK cells of natural killer cells in $1{\times}10^5$ trophosoite infected mice was significantly increased on the 12th hour and the first day after infection as compared with the control group. Maximal recycling capacity (MRC) was not changed during the observation period. The present results indicated that the elevation of natural killer cell activity in the mice infected with A. culbertsoni was due to elevation of target.binding capacity and increased active NK cells of natural killer cells, and not due to the maximal recycling capacity of the individual NK cell, and there was no difference between two experimental dose groups.

  • PDF

Prevention of calcification in bovine pericardial bioprosthesis -pretreatment with surfactants- (우심낭편의 석회화 방지에 관한 연구 - 계면활성제 전처치 효과 -)

  • 안재호;한재진;박성수
    • Journal of Chest Surgery
    • /
    • v.31 no.6
    • /
    • pp.560-566
    • /
    • 1998
  • Background: Bovine pericardial bioprosthesis treated with glutaraldehyde (GA) is one of the most popular prosthetic materials, but late calcific degeneration after implantation is a problem that remains unsolved. For the purpose of mitigating the calcific degeneration, we added MgCl2 into the 0.625% GA solution to compete with calcium for binding to the free aldehyde from GA and pretreated with the surfactants like sodium dodecyl sulfate (SDS) and Triton X-100 before GA fixation for preventing the phospholipid infiltration into the pericardial tissue, the first step of the calcific degeneration. Material and Method: 40 square-shaped pieces of bovine pericardia were fixed in 0.625% GA solution with 4g/L MgCl2 6H2O as a control group (group 1). 40 pieces pretreated with 1% SDS were also fixed in the same GA solution (group 2) and other 40 pieces pretreated with 1% Triton X-100 were prepared with the same method (group 3). After 1 month of fixation these were implanted into the belly of 40 Sprague-Dawley subdermally and extracted 1 month, 2 months, 3 months and 6 months after implantation. With atomic absorption spectrophotometry we measured the deposited calcium amount. Result: 1 month after implantation we could not find any differences between the three groups, but by the 2nd month calcium deposition was 0.921$\pm$0.121 mg/g in group 1, 0.481$\pm$0.037 mg/g in group 2 and 1.369$\pm$0.200 mg/g in group 3. By the 3rd month it was 0.786$\pm$0.080 mg/g in group 1, 0.584$\pm$0.054 mg/g in group 2 and 1.139$\pm$0.188 mg/g in group 3, and on the 6th month 1.623$\pm$0.601 mg/g in group 1,0.501$\pm$0.043 mg/g in group 2 and 1.625$\pm$0.382 mg/g in group 3, with statistical significance in group 2(p<0.05). Conclusion: Pretreatment with SDS showed meaningful calcium mitigation effects on subcutaneously implanted bovine pericardium in the rat models but the neutral type surfactant, Triton X-100, had no positive mitigation effect in this experiment.

  • PDF