• Title/Summary/Keyword: pH agent

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Study on iodine Labelling (II) Efficient of Labelling Rose Bengal, Hippuran, and Human Serum Albumin in Small Scale

  • Kim, Jaerok
    • Nuclear Engineering and Technology
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    • v.4 no.3
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    • pp.186-193
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    • 1972
  • For efficient micro scale syntheses of Rose $Bengal-^{131}I$, $Hippuran-^{131}I$, and $H.S.A.-^{131}I$, the dependence of labelling yields on pH, on salt contents, and on the volume of buffer solution in the reaction mixtures as well as the reaction apparatus were studied. pH of 5.6 was optimum for preparation of both Rose $Bengal-_{131}I$ and Hippuran $-^{13}I$ but pH of 8.5 was optimum for preparation of $H.S.A.-^{131}I$. Salt in the reaction mixtures hindered drastically the formation of $Hippuran-^{131}I$ but it slightly increased the labelling yield of H.S.A.. The compactly closed reaction vessels were effective for preparations of both Rose $Bengal-^{131}I$and $Hippuran-^{131}I$ in small volume. Thereupon, the labelling procedures were modified to bring about higher labelling yields and better reproducibilities. By these newly established procedures, the labelling yields of Rose $Bengal-^{131}I$ and $Hippuran-^{131}I$ could be increased even with the home-produced sodium $iodide-^{131}I$ solution containing reducing agent.

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Gemcitabine-induced Cell Death in Lung Cancer Cells : the Role of p53 (폐암 세포에서 Gemcitabine에 의한 세포 사멸과 p53의 역할)

  • Kim, Doh-Hyung;Bae, Gang-U;Yong, Wha-Shim;Choi, Eun-Kyung;Kim, Youn-Seup;Park, Jae-Seuk;Jee, Young-Koo;Lee, Kye-Young
    • Tuberculosis and Respiratory Diseases
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    • v.53 no.3
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    • pp.275-284
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    • 2002
  • Background : Gemcitabine is a new anti-cancer agent for treating non-small cell lung cancer. Functioning as an antimetabolite, it induces anti-cancer effects by suppressing DNA synthesis after being incorporated into the DNA as a cytosine arabinoside analogue. When Gemcitabine is incorporated into the DNA, the p53 gene may be activated by induction of the DNA defect. However, there are a few studies on the molecular mechanisms of Gemcitabine-induced cell death. This study examined the role of p53 in Gemcitabine-induced cell death. Methods : A549 and NCl-H358 lung cancer cells were used in this study. The cell viability test was done using a MTT assay at Gemcitabine concentrations of 10nM, 100nM, 1uM, 10uM and 100uM. A FACScan analysis with propium iodide staining was used for the cell cycle analysis. Western blot analysis was done to investigate the extent of p53 activation. For the functional knock-out of p53, stable A549-E6 cells and H358-E6 cells were transfected pLXSN-16E6SD which is over expresses the human papilloma virus E6 protein that constantly degrades p53 protein. The functional knock out of p53 was confirmed by Western blot analysis after treatment with a DNA damaging agent, doxorubicine. Results : Gemcitabine exhibited cell toxicity in dose-dependent fashion. The cell cycle analysis resulted in an S phase arrest. Western blot analysis significant p53 activation in time-dependent manner. Gemcitabine-induced cytotoxicity was reduced by 20-30% in the A549-E6 cells and the 30-40% in H358-E6 cells when compared with the A549-neo and H358-neo control cells. Conclusion : Gemcitabine induces an S phase arrest, as expected for the anti-metabolite, and activates the p53 gene, Furthermore, p53 might play an important role in Gemcitabine-induced cell death. Further investigation into the molecular mechanisms on how Gemcitabine activates the p53 gene and its signaling pathway are recommended.

A Study on Adsorption Characterics of Metallic Ions by Tannin Immobilized on Chitin and Chitosan (Chitin 및 Chitosan에의 고정화 탄닌의 금속이온 흡착특성에 관한 연구)

  • Kim, Chang-Ho;Chang, Byung-Kwon;Choi, Kyu-Suk
    • Applied Chemistry for Engineering
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    • v.4 no.1
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    • pp.204-215
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    • 1993
  • Epoxy-activated chitin was synthesized by the reaction of epichlorohydrin with chitin which was isolated from waste marine sources such as crab shell. Followed by the reaction of epoxy-activated chitin with hexamethylenediamine, the aminohexyl chitin was synthesized. The aminohexyl chitin was subsequently reacted with epichlorohydrin to prepare the epoxy-activated aminohexyl chitin. Finally, the tannin-immobilized chitin (Resin I) was synthsized by the reaction of tannin solution with epoxy-activated aminohexyl chitin. Using silane coupling agent, the tannin-immobilized chitosan(Resin II) was synthesized by the reaction of $\gamma$-glycidoxypropyltrimethoxy silane with chitosan which was prepared by the deacetylation of chitin. Upon the pH variation, adsorptivities of these immobilized tannins to the metal ions such as $Cu^{+2}$, $Ni^{+2}$, $Cr^{+6}$, $Co^{+2}$, $Ca^{+2}$, $Pb^{+2}$, $Ba^{+2}$, and $UO_2{^{+2}}$ ions were determined by batch method. The adsorptivity tendencies of these immobilized tannin to the most of metallic ions were increased with pH. Furthermore, the adsorptivities of Resin(I) and Resin(II) upon the variation of pH, contact time, amount of resin and concentration of metal ion were investigated. As a result, it was found that these immobilized tannin on both chitin and chitosan showed good adsorptivities for uranyl ion.

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Dyeing Behavior of Silk/CDP Mixed Filament with a Cationic Dye (캐티온염료를 이용한 Silk/Cationic Dyeable Polyester 혼합사의 염색거동)

  • Choe, Jong-Mun;Gwon, Hae-Yong;Park, Yeong-Hwan
    • Journal of Sericultural and Entomological Science
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    • v.37 no.2
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    • pp.154-160
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    • 1995
  • Dyeing behavior of Silk/Cationic dyeable polyester(CDP) mixed filament was investigated by using a cationic dye. The effect of pH, temperature and additives such as carrier, levelling agent and salt were examined for each silk and CDP component of mixed filament in order to find out the optimum dyeing condition. Based on these results, the dyeing behavior was investigated for Silk/CDP mixed filaments concering various dyeing parameters. The dye adsorption was significantly changed on the dyeing temperature, carrier addition and pH of the dyebath. Specially, the dye migration phynomena were observed for a mixed filament, showing that the dyes initially observed on the surface of silk fiber migrate to the CDP component during a dyeing process. The dyeing of Silk/CDP mixed filaments accompanied by dye migration and as a result, dye adsorption can be developed only for a CDP component. Therefore, the control of dyeing temperature is most important for a Silk/CDP mixed filament, in order that both silk and CDP component are able to be dyed by a cationic dye simultaneously in one bath/one dye system.

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Effect of Temperature and pH on Trypsin Inhibitory Activity of Ethanol Extracts from Ecklonia cava (감태 에탄올 추출물의 Trypsin 저해활성에 대한 열 및 pH의 영향)

  • Jeong, Hee-Ye;Kim, Koth-Bong-Woo-Ri;Jung, Seul-A;Kim, Hyun-Jee;Jeong, Da-Hyun;Lee, Ga-Yeong;Kang, Bo-Kyeong;Bark, Si-Woo;Kim, Tae-Wan;Cho, Young-Je;Ahn, Dong-Hyun
    • KSBB Journal
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    • v.27 no.6
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    • pp.330-334
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    • 2012
  • This study was performed to investigate the inhibitory activity of ethanol extract from Ecklonia cava (EE-EC) against trypsin and the stability of this activity under various heat and pH conditions. As a results, The EE-EC showed trypsin inhibitory activity of 77, 54, and 32% at concentrations of 5, 2.5, and 1 mg/mL and was not affected by the heat treatment conditions used in this study. Whereas trypsin inhibitory activity of EE-EC was stable in the pH range of 2-8, but decreased with pH treatment of pH 10 compared with the control. Therefore, the EE-EC could be useful as a natural and functional agent.

The Crystal Structure of Acemetacin Monohrdrate $(C_{21}H_{18}NO_6Cl-H_2O)$, A Non-Steroidal Antiinflammatory Agent

  • Kim, Yang-Bae;Kim, Jeong-Ae;Park, Yeong-Il
    • Archives of Pharmacal Research
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    • v.16 no.2
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    • pp.134-139
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    • 1993
  • The molecular structure of acemetacin, 1-(4-chlorobenzoyl)-5-methoxy-2-methyl-1H-indole-3-acetic acid carboxymethyl ester, was determined by single cystal X-ray diffraction analysis. The compound was recrystallized from a mixture of acetone and water in triclinic, space group P1, with a=7.796(1), b=10.245(2), c=13.542(3)$\AA,\;\alpha=97.35(1),\;\beta=96.34(1),\;\gamma=107.06(1)^\circ$, and Z=2. The calculated density is 1.422; the observed value is $1.42\;g/cm^3$. The structure was solved by the direct method and refined by full matrix least-squares procedure to the final R value of 0,037 for 2960 independent reflections. There are water molecules, which are thought to be co-crystallized during the evaporation procedure, with the ratio of one water per compound molecule in the crystal. The conformation of the compound is found to be very similar to that of indomethacin. The molecules are stabilized by three O-H.....O type intermolecular hydrogen bonds between the oxygen of water molecule and those of the compound.

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Evaluation of Electrolyzed Oxidizing Water as a Control Agent of Cucumber Powdery Mildew

  • Lee, Yong-Hwan;Cha, Kwang-Hong;Ko, Sook-Ju;Park, In-Jin;Park, Boung-In;Seong, Ki-Young
    • The Plant Pathology Journal
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    • v.16 no.4
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    • pp.206-210
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    • 2000
  • The effect of the electrolyzed oxidizing water on Sphaerotheca fuliginea was investigated with germination and sporulation of the fungal conidia. The sporulation was inhibited by the electrolyzed oxidizing water of pH 2.5, 3.5, and 4.5, but was not inhibited by the distilled water adjusted pH with 1N-HCL solution. However, the electrolyzed oxidizing water did not affect conidial germination. The oxidation-reduction potential at pH 2.5 and pH 3.5 of electrolyzed oxidizing water were 1130 mV and 1060 mV, respectively, but those of distilled water adjusted with HCL solution were 550 mV and 490 mV, respectively. When the electrolyzed oxidizing water of ORP over 1100 mV was sprayed on cucumplanting, the disease severities of powdery mildew were about 8.5% and 19.2%, respectively. Disease severity of a standard control (triflumizole 30% WP, $500\textrm{mg}\textrm{/L}$) was about 3.0%, while that of plants without electrolyzed oxidizing water was to 45.8%.

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Characterization and Functional Properties of an Oat Gum Extracted from a Drought Harvested Oat (Avena sativa)

  • Ramos-Chavira, Naivi;Carvajal-Millan, Elizabeth;Rascon-Chu, Agustin;Marquez-Escalante, Jorge;Santana-Rodriguez, Victor;Salmeron-Zamora, Juan
    • Food Science and Biotechnology
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    • v.18 no.4
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    • pp.900-903
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    • 2009
  • An oat gum was extracted from whole seeds of a drought harvested oat (Avena sativa). Oat gum presented a ${\beta}-glucan$ content of 65%(w/w) and an intrinsic viscosity of 141 mL/g. Gelling capability of oat gum at different concentrations was investigated. Gel hardness increased from 0.08 to 0.25 N as the oat gum concentration changed from 5 to 10%(w/v). Whippability, foam stability, emulsion stability, and reduced viscosity of oat gum at different pH were also investigated. Oat gum whippability was maximum at pH 7 (146%), while the higher foam and emulsion stability values were found at pH 9 (88 and 96%, respectively). The gum reduced viscosity increased from 715 to 958 mL/g as the pH changed from 7 to 9. Oat gum shows great potential as a gel forming, thickening, and stabilizing agent.

Inhibitory Effect of Pine Needle(Pinus densiflora S.) Extract on Potato Polyphenol Oxidase (감자 polyphenol oxidase에 대한 솔잎 추출물의 저해효과)

  • Lee, Min-Kyung
    • Journal of Life Science
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    • v.16 no.5
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    • pp.866-869
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    • 2006
  • The inhibitory effect of pine needle (Pinus densiflora S.) on potato polyphenol oxidase (PPO) was investigated. The addition of the pine needle extract exhibited a higher inhibitory effect on the potato polyphenol oxidase activity than that of the citric acid or potassium sorbate. The enzyme activity was strongly inhibited in a pH range of 7.0-8.0. When the incubation time of reaction mixture was increased, the potato polyphenol oxidase activity was markedly inhibited. The pine needle extract inhibited the potato polyphenol oxidase non-competitively. And also the pine needle extract subjected to a heat treatment at $100^{\circ}C$ for 10 min or to an acid treatment at pH 2.0, 3.0, and 4.0 for 3 hours still retained inhibitory effect on potato polyphenol oxidase.

Determination of Total Chlorine Residuals by Flow Injection Analysis (흐름 주입 분석법에 의한 총 잔류염소의 정량)

  • Choi, Yong Wook
    • Journal of the Korean Chemical Society
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    • v.43 no.4
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    • pp.430-437
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    • 1999
  • The determination of total chlorine residuals in drinking water by flow injection analysis(FIA) with iodometric UV detection was investigated. The pH of the acid stream, the concentration of the iodide ion,the length of the mixing and reaction coils, the injection sample size, and flowrate were optimized as parameters for determining total chlorine residuals by FIA method. lodide was selectively oxidized to iodine by hypochlorite at pH 8.3 Ethylenediamine as masking agent for masking interference ions from the sample was given the best efficency. Calibration curve presented linear range of 0.03-3 mg/L for hypochlorite ion with a correlation coefficient of 0.999 or better. The detection limit was found to be 0.007 mg/L for hypochlorite ion. Under these analytical conditions, total chlorine residuals in several tap water sampled in the city of Jeonju were analyzed.

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