• Title/Summary/Keyword: negative shift

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NF-${\kappa}B$ Activation and cIAP Expression in Radiation-induced Cell Death of A549 Lung Cancer Cells (A549 폐암세포주의 방사선-유도성 세포사에서 NF-${\kappa}B$ 활성화 및 cIAP 발현)

  • Lee, Kye Young;Kwak, Shang-June
    • Tuberculosis and Respiratory Diseases
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    • v.55 no.5
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    • pp.488-498
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    • 2003
  • Background : Activation of the transcription factor NF-${\kappa}B$ has been shown to protect cells from tumor necrosis factor-alpha, chemotherapy, and radiation-induced apoptosis. NF-${\kappa}B$-dependent cIAP expression is a major antiapoptotic mechanism for that. NF-${\kappa}B$ activation and cIAP expression in A549 lung cancer cells which is relatively resistant to radiation-induced cell death were investigated for the mechanism of radioresistance. Materials and methods : We used A549 lung cancer cells and Clinac 1800C linear accelerator for radiation. Cell viability test was done by MTT assay. NF-${\kappa}B$ activation was tested by luciferase reporter gene assay, Western blot for $I{\kappa}B{\alpha}$ degradation, and electromobility shift assay. For blocking ${\kappa}B$, MG132 and transfection of $I{\kappa}B{\alpha}$-superrepressor plasmid construct were used. cIAP expression was analyzed by RT-PCR and cIAP2 promoter activity was performed using luciferase assay system. Results : MTT assay showed that cytotoxicity even 48 hr after radiation in A549 cells were less than 20%. Luciferas assay demonstrated weak NF-${\kappa}B$ activation of $1.6{\pm}0.2$ fold compared to PMA-induced $3.4{\pm}0.9$ fold. Radiation-induced $I{\kappa}B{\alpha}$ degradation was observed in Western blot and NF-${\kappa}B$ DNA binding was confirmed by EMSA. However, blocking NF-${\kappa}B$ using MG132 and $I{\kappa}B{\alpha}$-superrepressor transfection did not show any sensitizing effect for radiation-induced cell death. The result of RT-PCR for cIAP1 & 2 expression was negative induction while TNF-${\alpha}$ showed strong expression for cIAP1 & 2. The cIAP2 promoter activity also did not show any change compared to positive control with TNF-${\alpha}$. Conclusion : We conclude that activation of NF-${\kappa}B$ does not determine the intrinsic radiosensitivity of cancer cells, at least for the cell lines tested in this study.

Electrochemical Reduction for trans-Complexes of Cobalt (III) with Bis(ethylenediamine) and Monodendate Ligands (한자리 리간드를 포함하는 트란스비스 (에틸렌디아민) 코발트 (III) 이온의 전극 환원반응)

  • Jung-Ui Hwang;Jong-Jae Chung;Jae-Duck Lee
    • Journal of the Korean Chemical Society
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    • v.33 no.2
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    • pp.215-224
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    • 1989
  • Electrochemical reductions of $trans-[Co(en)_2X_2](ClO_4)_n$ (where X is cyanide, nitrite, ammonia, and isothiocyanate) were investigated by cyclic voltammetry and polarography at mercury and glassy carbon electrode. $trans-[Co(en)_2(CN)_2]ClO_4$ was reduced to Co(II) complex followed by adsorption to the mercury electrode. Cyanide ion was not released from the reduced Co(II) complex but the cyanide and (en) were released after the reduction to metallic cobalt. The other complexes except $trans-[Co(en)_2(CN)_2]ClO_4$ were reduced to cobalt(II) complexes followed by release of monodendate ligand, and (en) was released at the reduction step to metallic cobalt. $trans-[Co(en)_2(NO_2)_2]ClO_4$ was reduced to cobalt(Ⅱ) complex, and $NO_2^-$ ion was released followed by electroreduction through ECE mechanism at pH 2. On glassy carbon electrode, all complexes of Co(III) were reduced to Co(II) complexes with irreversible one-electron diffusion controlled reaction in which (en) was not released at this step. Increasing absorption wave number of complexes caused to negative shift of peak potential.

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Studies on the Spectrophotometric Determination, Electrochemical Behavior of Heavy Lanthanide ions in Nonaqueous System and Heavy Chelates Complexes with Bidendate Ligands (Ⅱ) Electrochemical Behavior of Heavy Lanthanide Ions in Acetonitrile (무거운 란탄이온의 분광학적 정량, 비수용액에서의 전기화학적 거동 및 중금속이온과 두자리 리간드 착물에 관한 연구 (제 2 보))

  • Kang Sam-Woo;Park Chong-Min;Kim Il-Kwang;Do Lee-Mi;Lee Jong-Min
    • Journal of the Korean Chemical Society
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    • v.37 no.5
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    • pp.483-490
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    • 1993
  • Voltammetric behavior of heavy lanthanide ions has been investigated by the DC, DPP and CV in acetonitrile solution. The reduction of $Gd^{3+}, Tb^{3+}, Dy^{3+}, Ho^{3+}, Er^{3+}, Tm^{3+} 및 Lu^{3+} proceed by three-electron change to the metallic state with totally irreversibility in 0.1M tetraethylammonium perchlorate. However, the reduction of Yb(Ⅲ) proceeds in two steps $(Yb^{3+} + e^- \Leftrightarrow Yb^{2+} and Yb^{2+} + 2e^- → Yb^0)$. The first reduction of Yb(Ⅲ) showed quasi reversible behavior, but the second reduction was irreversible in cyclic voltammetry. The cathodic peak current showed adsorptive properties in high concentration with lower sweep rate. The electroreduction of heavy lanthanides in water-acetonitrile mixture has been studied. In water-acetonitrile mixture, the negative shift of the peak potential and the decrease peak current were observed increasing water concentration. Also the Yb(Ⅲ) reduction to Yb(Ⅲ) has been deviated from quasi-reversible character with increase water amount. These results drive from the high solvation abilities of water which has high donor number.

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Binding Properties of Anthryl Derivatives to Synthetic Polynucleotide and the Role of Guanine Amine Group in the Energy Transfer (안트라센 유도체-합성DNA의 결합형태와 에너지전달과정에서 구아닌 염기의 아민기의 역할)

  • Cho, Chang-Beom;Son, Gwan-Su;Han, Sung-Wook;Jung, Maeng-Jun;Chong, Hyun-Suk;Lee, Gil-Jun
    • Journal of the Korean Chemical Society
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    • v.44 no.1
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    • pp.45-51
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    • 2000
  • The binding mode of anthryl derivatives to synthetic polynucleotides were investigated by various spectroscopic methods. The spectroscopic properties of anthracence with metbylamine and methylethylenediamine side chains, complexed with $poly[d(A-T)_2]$ and $poly[d(G-C)_2]$, can be summarized as a red-shift, with a strong hypochromism in the absortion spectrum, similar induced CD spectra, and a strong negative LD spectrum with an $LD^r$ magnitude comparable to the DNA absorption region. These observations indicate that anthracene moiety is intercalated between the nucleo-bases of $poly[d(A-T)_2]$ and $poly[d(G-C)_2]$. The side chains did not alter the spectroscopic properties, demonstrating that the binding mode was not affected by them. A strong energy transfer was observed from poly[d(A-T),] and $poly[d(I-C)_2]$ but not from $poly[d(G-C)_2]$, as reported by Kumar et al. (J. Am. Chem. Soc.(1993) 115, 8547). Since the binding mode is the same for all the polynucleotides, the amine group of the guanine base, which protrudes into the minor groove of $poly[d(G-C)_2]$, is concluded to disrupt the energy transfer.

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The Evaluation of Teicoplanin Usage in a University Hospital (대학병원에서의 Teicoplanin의 사용 현황 조사 및 실태 평가)

  • Kim, Eun A;Oh, Jung Mi
    • Korean Journal of Clinical Pharmacy
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    • v.11 no.1
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    • pp.19-29
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    • 2001
  • Teicoplanin, a glycopeptide antibiotic, has potential for use as an alternative to vancomycin in the treatment of gram-positive bacterial infections. However, unlike vancomycin, there is a lack of study on teicoplanin's efficacy and safety and the guideline for its use is not available, yet. The objective of this study was to investigate and evaluate the pattern of teicoplanin usage in a university hospital. A retrospective study was performed on 72 adult patients, who took teicoplanin for 3 continuous days at D. University hospital from 1 January 1999 to 30 June 2000. The microorganisms treated with teicoplanin were methicillin-resistant Staphylocorcus aureus $(69\%)$, coagulase-negative Staphylococci $(12\%)$, Enterococcus $(4\%)$, vancomycin-resistant Enterococci $(2\%)$, Streptococci $(2\%)$, and Bacillus $(1\%)$. The types of infection treated with teicoplanin were surgical wound infection $(58\%)$, lower respiratory infection $(11\%)$, bactremia $(7\%)$, urinary tract infection $(5\%)$, pleural fluid infection $(4\%)$, and peritoneal fluid infection $(2\%)$. The mean duration of teicoplanin usage was 16.5 days and teicoplanin was used with 1.4 other antibiotics, which were aminoglycosides (isepamicin, amikacin, netilmicin, astromicin) or quinolones (ciprofloxacin, tosufloxacin) or the third generation cephalosporin (ceftazidime). Only 24 cases $(28.6\%)$ met with the criteria for the justification of use, and the rest of 60 cases $(71.4\%)$ did not meet the criteria. In 84 cases $(100\%)$, blood culture tests were performed prior to the initial dose of teicoplanin. In 83 cases $(99\%)$, serum creatinine were conducted before the initial doses. In 45 cases $(53.6\%)$, serum creatinine was monitored at least twice weekly. In 55 cases $(65.5\%)$, WBC was tested at least twice weekly. In 84 cases $(100\%)$, body temperature was monitored at least once per nursing shift. In 15 cases out of 56 cases, maximum temperature decreased at least 1 degree within 3 days of teicoplanin use. In 15 case out of 35 cases, WBC values were within the normal range after treatment. In 23 cases $(27.4\%)$, dosage regimen was appropriate. Drug-related adverse effects were reported in 13 cases. Nephrotoxicity (progressively increasing SCr. or sustained SCr increase of $\geq$0.5 mg/dl from baseline) was noted in five cases. Neutropenia (absolute neutrophil count <1,500 $cells/mm^3$) was noted in one case and eosinophilia (total eosinophil count >350 $cells/mm^3$) was noted in seven cases. A more strict control on use of teicoplanin is required, considering that teicoplanin is categorized as one of restricted antibiotics.

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Transcriptional Regulation of a DNA Repair Gene in Saccharomyces cerevisiae

  • Jang, Yeon-Kyu;Sancar, Gwen-B.;Park, Sang-Dai
    • Proceedings of the Zoological Society Korea Conference
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    • 1998.10b
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    • pp.113-113
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    • 1998
  • In Saccharomyces cerevisiae UV irradiation and a variety of chemical DNA -damaging agents induce the transcription of specific genes, including several involved in DNA repair. One of the best characterized of DNA -damage inducible genes is PHRI, which encodes the apoenzyme for DNA photolyase. Basal-level and damage-induced expression of PHRI require an upstream activation sequence, UASPHRI. Here we report the identification of the UlvIE6 gene of S. cerevisiae as a regulator of UASPHRl activity. Surprisingly, the effect of deletion of UME6 is growth phase dependent. In wild-type cells PHRI is induced in late exponential phase, concomitant with the initiation of glycogen accumulation that precedes the diauxic shift. Deletion of UNIE6 abolishes this induction, decreases the steady-state concentration of photolyase molecules and PHRI mRNA, and increases the UV sensitivity of a rad2 mutant. The results suggest that UM E6 contributes to the regulated expression of a subset of damage-responsive genes in yeast. Furthermore, the upstream repression sequence, URSPHRI, is required for repression and damage-induced expression of PHRl. Here we show identification of YER169W and YDR096W as putative regulators acting through $URS_{PHRI}$. These open reading frames were designated as RPHI (YERl69W) and RPH2 (YDR096W) indicating regulator of PHRI. Simultaneous disruption of both genes showed a synergistic effect, producing a four-fold increase in basal level expression and a similar decrease m the induction ratio following treatment of methyl methanesulfonate(MMS). Mutation of the sequence ($AG_4$) bound by Rphlp rendered the promoter of PHRI insensitive to changes in RPHI or RPH2 status. The data suggest that RPHI and RPH2 act as damage-responsive negative regulators of PHRI. Surprisingly, the sequence bound by Rphlp in vitro is found to be $AG_4$ which is identical to the consensus binding site for the regulators Msn2p and Msn4p involved in stress-induced expression. Deletion of MSN2 and MSN4 has little effect on the induction$.$ ratio following DNA damage. However, all deletions led to a significant decrease in basal-level and induced expression of PHRI. These results imply that MSN2 and MSN4 are positive regulators of P HRI but are not required for DNA damage repression. [Supported by grant from NIH]om NIH]

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Energy Perspective of Sugar Industries in Pakistan: Determinants and Paradigm Shift

  • Siddiqui, Muhammad Ayub;Shoaib, Adnan
    • Journal of Distribution Science
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    • v.10 no.2
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    • pp.7-17
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    • 2012
  • The aim of this study is to empirically explore micro and macroeconomic factors affecting the Pakistani sugar industries and searching the energy potential of this industry, through the survey of literature. The empirical part has been explored by employing Vector Autoregression (VAR), Granger Causality tests and simultaneous equation models through quarterly data for the period of 1991q2-2008q4. The study also aims to devise policies for the development of sugar industries and identify its growing importance for the energy sector of Pakistan. Empirical tests applied on the domestic prices of sugar, domestic interest rates, and exchange rate, productive capacities of sugar mills, per capita income, world sugar prices on cultivable area and sugar production reveal very useful results. Results reveal an improvement of productive capacity of the sugar mills of Pakistan on account of increasing crushing capacity of this sector. Negative effect of rising wholesale prices on the harvesting area was also observed. Profit earnings of the sugar mills significantly increase with the rise of sugar prices but the system does not exist for the farming community to share the rising prices of sugar. The models indicate positive and significant effect of local prices of sugar on its volume of import. Another of the findings of this study positively relates the local sugar markets with the international prices of sugar. Additionally, the causality tests results reveal exchange rate, harvesting area and overall output of sugarcane to have significant effects on the local prices of sugar. Similarly, import of sugar, interest rate, per capita consumption of sugar, per capita national income and the international prices of sugar also significantly affect currency exchange rate of Pakistani rupee in terms of US$. The study also finds sugar as an essential and basic necessity of the Pakistani consumers. That is why there are no significant income and price effects on the per capita consumption of sugar in Pakistan. All the empirical methods reiterate the relationship of variables. Economic policy makers are recommended to improve governance and management in the production, stock taking, internal and external trading and distribution of sugar in Pakistan using bumper crop policies. Macroeconomic variables such as interest rate, exchange rate per capita income and consumption are closely connected with the production and distribution of sugar in Pakistan. The cartelized role of the sugar industries should also be examined by further studies. There is need to further explore sugar sector of Pakistan with the perspective of energy generation through this sector; cartelized sugar markets in Pakistan and many more other dimensions of this sector. Exact appraisal of sugar industries for energy generation can be done appropriately by the experts from applied sciences.

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Practice and Theory of RYUTSUKEIRETSUKA(Vertical Marketing System) by the Japanese Leading Manufacturers (일본 과점메이커의 유통계열화의 현실과 이론)

  • Choi, Sang-Chul
    • Journal of Distribution Research
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    • v.16 no.5
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    • pp.211-231
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    • 2011
  • RYUTSUKEIRETSUKA(Vertical Marketing System) developed by the Japanese Leading Manufacturers began to turn weak with the presence of the large- scaled retail enterprises since 1980’s. Therefore the alliances between major manufacturers & large distributors that were in the conflict relations for a long time began to progress. In accordance with this change in the distribution channel practice, the stance of the distribution channel theory in Japan had also changed. As the normative researcher group who had been critical to RYUTSUKEIRETSUKA and sympathetic to the task of merchant judged that it would disappear sooner or later, they considered positively the alliances between major manufacturers & large distributors which the latter were in dominant position. On the other hand, even the empirical researchers who supported the affirmative function of RYUTSUKEIRETSUKA changed their standpoint. They recognized the new channel practice, in other words the vertical alliances between the power companies, would be the frontier of research in accordance with the impetus of positivism in terms of the Marketing methodology. Thus, researchers of distribution channel theory in Japan who supported the normative approach become few and even changed to hurry to absorb in the empirical research, while moving the main focus of the research from RYUTSUKEIRETSUKA to the Alliances. In the long run, the distribution channel theory which was regarded as the leading principle of the Japanese Marketing has just made the methodological paradigm shift. The author suggests a critical viewpoint against the current Japan’s academism with the assumption that RYUTSUKEIRETSUKA has negative aspects.

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A Study on Relationships among Resilience, Stress, Burnout and Organizational Commitment of Hospital Nurses (간호사의 회복탄력성, 스트레스, 소진, 조직몰입과의 관계)

  • Ryu, Kyung;Kim, Jong Kyung
    • The Journal of the Korea Contents Association
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    • v.16 no.7
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    • pp.439-450
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    • 2016
  • Clinical nurses have tendency to change their job while providing care to patient, experiencing extreme stress with shift work, increased demands for technique, and heavy workload. At this point, it is time for investigating resilience in nursing part, and resilience affect to increase organizational commitment and decrease stress and exhaustion at organization. This study is a correlation study to investigate effects resilience on stress, exhaustion, and organizational commitment of clinical nurses. The results are as follows; The participants' resilience level is 3.38(${\pm}.38$), at the maximum of 5, stress level is 3.73(${\pm}.50$) at the maximum of 5, burnout level is 2.74(${\pm}.68$) at the maximum of 6 and organizational commitment level is 4.22(${\pm}.68$) at the maximum of 7. Ftom this study, resilience, stress, and burnout showed negative correlation, and resilience and organizational commitment revealed positive correlation. In order to decrease the clinical nurses' stress, burnout and enhance nurses' organizational commitment, nurse managers have to manage nurses' resilience. For increasing resilience of nurses, nurse manager has to develop resilience program, and training for managing nurses' stress and burnout.

Electrochemical Determinations of Methylanilinium Ion Mixtures by the Stereoselective Complexations of Host-Guest (호스트-게스트의 입체선택적 착물형성에 의한 메틸아닐리늄 이온 혼합물의 전기화학적 분석)

  • Jung, Jong Hwa;Chang, Duk Jin;Lee, Bu-Yong;Seo, Mu Ryong;Kim, Jae Sang;Lee, Shim Sung
    • Analytical Science and Technology
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    • v.5 no.3
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    • pp.239-247
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    • 1992
  • The complexations and selectivities of the 10 species of mono- and dimethylsubstituted anilinium ions with 18-crown-6 in methanol are examined at dropping mercury electrode. The stability constants of these complexes varies drastically due to the steric hindrance by the positions and numbers of methyl groups. And the analyses of the isomeric mixtures of methylanilinium, which are impossible to detect due to the overlapped peaks in normal conditions, were also accomplished by the additions of 18-crown-6 as the supporting complexing agent using the selective complexations by the steric hindrance effects. As results in case of the difference of stability, ${\Delta}log\;K$ were about 0.7~1.3, it was possible to confirm the existence of two species qualitatively. Otherwise when ${\Delta}log\;K$ were large than 1.6, the quantitative determinations of each species could be accomplished sucessfully. From these results it is deduced that the selective recongnition of the positions and numbers of methyl groups as the steric hindrance in anililniums by 18-crown-6 cause the large variation of the magnitudes of negative shift of reduction waves for guest ions in mixtures.

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