• Title/Summary/Keyword: A new reagent

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Optimization of soaking in aqueous ammonia pretreatment of canola residues for sugar production (당 생산을 위한 카놀라 부산물의 암모니아 침지 전처리 공정의 최적화)

  • Yoo, Hah-Young;Kim, Sung Bong;Lee, Sang Jun;Lee, Ja Hyun;Suh, Young Joon;Kim, Seung Wook
    • 한국신재생에너지학회:학술대회논문집
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    • 2011.11a
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    • pp.114.1-114.1
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    • 2011
  • Bioenergy production from lignocellulosic biomass and agriculture wastes have been attracted because of its sustainable and non-edible source. Especially, canola is considered as one of the best feedstock for renewable fuel production. Oil extracted canola and its agriculture residues are reuseable for bioethanol production. However, a pretreatment step is required before enzymatic hydrolysis to disrupt recalcitrant lignocellulosic matrix. To increase the sugar conversion, more efficient pretreatment process was necessary for removal of saccharification barriers such as lignin. Alkaline pretreatment makes the lignocellulose swollen through solvation and induces more porous structure for enzyme access. In our previous work, aqueous ammonia (1~20%) was utilized for alkaline reagent to increase the crystallinity of canola residues pretreatment. In this study, significant factors for efficient soaking in aqueous ammonia pretreatment on canola residues was optimized by using the response surface method (RSM). Based on the fundamental experiments, the real values of factors at the center (0) were determined as follows; $70^{\circ}C$ of temperature, 17.5% of ammonia concentration and 18 h of reaction time in the experiment design using central composition design (CCD). A statistical model predicted that the highest removal yield of lignin was 54% at the following optimized reaction conditions: $72.68^{\circ}C$ of temperature, 18.30% of ammonia concentration and 18.30 h of reaction time. Finally, maximum theoretical yields of soaking in aqueous ammonia pretreatment were 42.23% of glucose and 22.68% of xylose.

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ROS Scavenger, Ebselen, Has No Preventive Effect in New Hearing Loss Model Using a Cholesterol-Chelating Agent

  • Lee, Min Young;Kabara, Lisa L.;Swiderski, Donald L.;Raphael, Yehoash;Duncan, R. Keith;Kim, Young Ho
    • Journal of Audiology & Otology
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    • v.23 no.2
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    • pp.69-75
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    • 2019
  • Background and Objectives: The antioxidant ebselen will be able to limit or prevent the ototoxicity arising from 2-hydroxypropyl-β-cyclodextrin (HPβCD). Niemann-Pick Type C (NPC) disease is a disorder of lysosomal storage manifested in sphingolipidosis. Recently, it was noted that experimental use of HPβCD could partially resolve the symptoms in both animals and human patients. Despite its desirable effect, HPβCD can induce hearing loss, which is the only major side effect noted to date. Understanding of the pathophysiology of hearing impairment after administration of HPβCD and further development of preventive methods are essential to reduce the ototoxic side effect. The mechanisms of HPβCD-induced ototoxicity remain unknown, but the resulting pathology bears some resemblance to other ototoxic agents, which involves oxidative stress pathways. To indirectly determine the involvement of oxidative stress in HPβCD-induced ototoxicity, we tested the efficacy of an antioxidant reagent, ebselen, on the extent of inner ear side effects caused by HPβCD. Materials and Methods: Ebselen was applied prior to administration of HPβCD in mice. Auditory brainstem response thresholds and otopathology were assessed one week later. Bilateral effects of the drug treatments also were examined. Results: HPβCD-alone resulted in bilateral, severe, and selective loss of outer hair cells from base to apex with an abrupt transition between lesions and intact areas. Ebselen co-treatment did not ameliorate HPβCD-induced hearing loss or alter the resulting histopathology. Conclusions: The results indirectly suggest that cochlear damage by HPβCD is unrelated to reactive oxygen species formation. However, further research into the mechanism(s) of HPβCD otopathology is necessary.

ROS Scavenger, Ebselen, Has No Preventive Effect in New Hearing Loss Model Using a Cholesterol-Chelating Agent

  • Lee, Min Young;Kabara, Lisa L.;Swiderski, Donald L.;Raphael, Yehoash;Duncan, R. Keith;Kim, Young Ho
    • Korean Journal of Audiology
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    • v.23 no.2
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    • pp.69-75
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    • 2019
  • Background and Objectives: The antioxidant ebselen will be able to limit or prevent the ototoxicity arising from 2-hydroxypropyl-β-cyclodextrin (HPβCD). Niemann-Pick Type C (NPC) disease is a disorder of lysosomal storage manifested in sphingolipidosis. Recently, it was noted that experimental use of HPβCD could partially resolve the symptoms in both animals and human patients. Despite its desirable effect, HPβCD can induce hearing loss, which is the only major side effect noted to date. Understanding of the pathophysiology of hearing impairment after administration of HPβCD and further development of preventive methods are essential to reduce the ototoxic side effect. The mechanisms of HPβCD-induced ototoxicity remain unknown, but the resulting pathology bears some resemblance to other ototoxic agents, which involves oxidative stress pathways. To indirectly determine the involvement of oxidative stress in HPβCD-induced ototoxicity, we tested the efficacy of an antioxidant reagent, ebselen, on the extent of inner ear side effects caused by HPβCD. Materials and Methods: Ebselen was applied prior to administration of HPβCD in mice. Auditory brainstem response thresholds and otopathology were assessed one week later. Bilateral effects of the drug treatments also were examined. Results: HPβCD-alone resulted in bilateral, severe, and selective loss of outer hair cells from base to apex with an abrupt transition between lesions and intact areas. Ebselen co-treatment did not ameliorate HPβCD-induced hearing loss or alter the resulting histopathology. Conclusions: The results indirectly suggest that cochlear damage by HPβCD is unrelated to reactive oxygen species formation. However, further research into the mechanism(s) of HPβCD otopathology is necessary.

A Comparative Study of Production of [68Ga]PSMA-11 with or without Cassette Type Modules (비 카세트 방식과 카세트 방식을 이용한 [68Ga]PSMA-11의 자동 합성 방법 비교)

  • Hyun-Sik, Park;Byeong-Min, Jo;Hyun-Ho, An;Hong-Jin, Lee;Jin-Hyeong, Lee;Gyeong-Jae, Lee;Byung-Chul, Lee;Won-Woo, Lee
    • The Korean Journal of Nuclear Medicine Technology
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    • v.26 no.2
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    • pp.15-19
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    • 2022
  • Purpose [68Ga]PSMA-11 is needed the high reproducibility, excellent radiochemical yield and purity. In term of radiation safety, the radiation exposure of operator for its production also should be considered. In this work, we performed a comparative study for the fully automated synthesis of [68Ga]PSMA-11 between non-cassette type and cassette type. Materials and Methods Two different type of modules (TRACERlab FX N pro for non-cassette type and BIKBox for cassette type) were used for the automated production of [68Ga]PSMA-11. According to the previously identified elution profile, Only 2.5 ml with high radioactivity was used for the reaction. After adjusting the pH of the reaction solution with HEPES buffer solution, the precursor was added and reacted with at 95 ℃ for 15 minutes. The reaction mixture was separated and purified using a C18 light cartridge. The product was eluted with 50% EtOH/saline solution and diluted with saline. It was completed by sterilizing filter. In the non-cassette type, the aforementioned process must be prepared directly. However, in the cassette method, synthesis was possible simply by installing a kit that was already completed. Results Both total [68Ga]PSMA-11 production time were 25±3(non-cassette type) and 23±3 minutes(cassette type). The radiochemical yield of the non-cassette type(65.5±5.7%) was higher than that of the cassette type(61.6±4.8%) after sterilization filter. The non-cassette type took about 120 minutes of preparation time before synthesis due to washing of synthesizer and reagent preparation. However, since the cassette type does not require washing and reagent preparation, it took about 20 minutes to prepare before synthesis. Both type of synthesizer had a radiochemical high purity(>99%). Conclusion The non-cassette type production of [68Ga]PSMA-11 showed higher radiochemical yield and lower cost than the cassette type. However, The cassette type has an advantage in terms of preparation time, convenience, and equipment maintenance.

Anti-Oxidative and Anti-inflammatory Effect of Combined Extract and Individual Extract of GamiSaengmaeksan (가미생맥산(加味生脈散) 및 개별약재의 항산화 및 항염증 효능에 대한 비교 연구)

  • Ji, Joong-Gu
    • The Korea Journal of Herbology
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    • v.31 no.1
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    • pp.69-75
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    • 2016
  • Objectives : The aim of this study is to investigate the various effects of individual or combined extract of GamiSaengmaeksan (GSS) on cell viability, anti-inflammatory and antioxidant activityMethods : In order to evaluate cytotoxicity, MTT assay was performed. We investigated the levels of proinflammatory cytokines such as tumor necrosis factor (TNF)-α and interleukin (IL)-6 and interleukin (IL)-1β, and nitric oxide(NO) in LPS-induced RAW 264.7 cells to check the effects on anti-inflammatory activity. The level of NO production in RAW 264.7 cells was measured by using Griess reagent. The levels of cytokines and ROS were measured by Luminex and Flow cytometry, respectively.Results : At concentration of 200 ㎍/㎖ GSS, cytotoxicity was observed in RAW 264.7 cells. However, at concentration less than 100 ㎍/㎖ of both combine and individual GSS, cytotoxicity was not observed in Raw 264.7 cells. However, the level of ROS in RAW 264.7 cells were decreased at both extract of 100 ㎍/㎖ GSS. Also, the level of NO in RAW 264.7 cells were decreased from extraction of concentration of 100 ug/ml in GSS and individual-extraction of Liriopis Tuber, White Ginseng and Glycyrrhizae Radix. In addition, productions of pro-inflammatory cytokines (TNF-α) in LPS-induced RAW 264.7 cells were decreased from extraction of concentration of 10 and 100 (㎍/㎖) in GSS and individual-extraction of Liriopis Tuber.Conclusions : It is concluded that combined extract of GSS appears to be more effective in anti-oxidation and anti-inflammatory effect than those in individual-extraction of GSS. These results may be developed as a raw material for new therapeutics to ease the symptoms related with inflammatory and oxidative stress.

Gas-chromatographic determination of methylthiohydantoin amino acid as N(O)-butyldimethylsilyl derivatives in amino acid sequencing with methylisothiocyanate (Methylisothiocyanate를 이용한 아미노산 배열결정시 N(O)-butyldimethylsilyl 유도체로서의 methylthiohydantoin 아미노산의 기체 크로마토그래피에 의한 분석)

  • Woo, Kang-Lyung
    • Applied Biological Chemistry
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    • v.35 no.2
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    • pp.132-138
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    • 1992
  • For effective determination of methylthiohydantoin amino acids(MTHs) by gas liquid chromatography in the protein sequencing, derivatization with N-methyl-N-(tert.-butyl-dimethylsilyl)trifluoroacetamide(MTBSTFA), a new silylating reagents, was attempted instead of trimethylsilyl(TMSi) derivatives by N,O-bis(trimethylsilyl)trifluoroacetamide(BSTFA) used up to the present and N(O)-butyldimethylsilyl MTHs derivatized by MTBSTFA were analysed on HP-1 capillary column. Twenty one protein amino acids except cystine were indentified. Especially arginine that did not detected with TMSi derivative on packed column until now was resolved by derivatization with MTBSTFA. N(O)-butyldimethylsilyl MTHs showed multiple peaks by MTBSTFA were proline, isoleucine, glycine and tyrosine and hydroxyproline especially showed several extraneous peaks more than two. Calibration curves of N(O)-butyldimethysilyl MTHs of amino acids in the range of $2.5\;nmol{\sim}7.5\;nmole$ showed good linearity. however, those of lysine, histidine and arginine showed linearity in the range of $5.0\;nmole{\sim}15.0\;nmole$. Correlation coefficients and regression coefficients of all calibration curves were highly significant(p<0.001).

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Preparation of Water-Resistant Humidity Sensor Using Photocurable Reactive Oligomers Containing Ionene Unit and Their Properties (이온넨 단위를 가지는 광경화성 반응성 올리고머를 이용한 내수성 습도센서의 제조 및 감습 특성)

  • Jeon, Young-Min;Gong, Myoung-Seon
    • Polymer(Korea)
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    • v.33 no.1
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    • pp.19-25
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    • 2009
  • New polyelectrolytes derived from ionene-containing photocurable reactive oligomer (PIDM) were prepared for water-resistant humidity-sensitive membranes. The mixture of PIDM, hexamethylene dimethacrylate (HDM), pentaerythritol triacrylate dimer (SP1013), and photoinitiator was simultaneously coated on the sensor electrode with photoinitiated radical polymerization. The pretreatment of the substrates with vinyl-type silane-coupling reagent was performed for improving the water durability and stability of the sensors at high temperature and humidity. When the resistance dependences on the relative humidity of the crosslinked PIDMs were measured, it was found that the resistance varied three orders of magnitude between 20 and 90%RH, which was required for the humidity sensor operating at ambient humidity. Their hysteresis, temperature dependence, response time, water durability, and high temperature/humidity stabilities were measured and evaluated as a humidity-sensing membrane.

연구논문 초록(1967~1978)

  • 한국표면공학회
    • Journal of Surface Science and Engineering
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    • v.16 no.4
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    • pp.199-214
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    • 1983
  • Up to this date, numerous methods of analysis of electroplating solutions are published. Some, however, need lots of works before reaching final results, or require high technique and special instruments, and also some are unaccurate due to unclearnes of end point. Like our undevelope countries, technicians of electoplating shops are most high school gradutes or under, and have not much knowledge on chemistry. Furthermore, those technicians have to control their plating solutions by themselves without having enough analytical laboratory equiIJment. Therefore, in this paper the simplest, besides accurate method is investigated after comparing nu.merous methods published. Among the methods of 'copper determinations from acid and alkaline copper plating baths, EDT A titration method are chosen, due to these methods are the simplest and fastest for the evaluation of metal content, without requiring any special instrument. For acid copper solutions, chelate titrations were accurate enough. Since the end point of titration of chelate method is variable according to the kind of .indicators androther metal's coexsistence as well as solution comIJonent, many difficulties were encountered from cyanide' copper, on the contrary of acid copper bath. PAN, PV, and MX indicators were tried, but it is found that MX is the best. In cyanide solution, due to cyanide is the masking reagent, elimination of this component is essential, and finally found that elimination eN- by precipitation with AgN03 solution was the simplest and the most accurate way among others. This method was very accurate for the new plating solutions even coexistence with organic brightners. However used solutions for long months running have to be predetermined the accurate copper value by thiosulfate method from time to time, before chelate titration by means of AgN03 precipitation. Always some constant deviatioJ;ls will be seen according to the solutions nature. Therefore those deviation values have to be compensated each time.

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Effect of novel luminol-based blood detection reagents on DNA stability (새로운 루미놀 기반 혈흔 탐지 시약이 디엔에이에 미치는 영향에 대한 연구)

  • Jung, Ju Yeon;Oh, Yu-Li;Lee, Jee Won;Lim, Seung;Kim, Jung-mok;Lee, Yang Han;Lim, Si-Keun
    • Analytical Science and Technology
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    • v.31 no.2
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    • pp.71-77
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    • 2018
  • Detection of bloodstains is a very important process in scientific investigations, and luminol is often used for the detection of bloodstains that are not visible. Recently, new preparation methods of blood detection reagents based on luminol (BloodFlareA, B) were developed and reported to have higher active persistence and to be more economical than conventional blood detection reagent, BlueStar forensic. In this paper, we tested the specificity and effect of the BloodFlares (A and B) on DNA and compared them with those of BlueStar forensic. False positive results for the BloodFlares were not observed in semen, saliva, vaginal fluids, urine, sweat, and nasal discharge, but were observed in $CuSO_4$, $FeSO_4$, and bleach solutions, and the observed patterns were similar to those of BlueStar forensic. The effect on DNA was determined by analyzing the DNA yield, degradation index, and DNA profiling. Based on these results, we concluded that the BloodFlares based on luminol do not affect DNA stability and are applicable in forensics.

Generation of a monoclonal antibody against AgI/II, a cellular surface protein of Streptococcus mutans GS5 (Streptococcus mutans GS5의 세포막 단백질 Ag I/II에 대한 단항체의 생산)

  • Cheon, Cheol-Wan;Baik, Byeong-Ju;Yang, Yeon-Mi;Han, Ji-Hye;Kim, Jae-Gon
    • Journal of the korean academy of Pediatric Dentistry
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    • v.33 no.4
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    • pp.587-596
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    • 2006
  • Most of oral streptococci express the Antigen I/II (AgI/II) proteins, cell wall anchored adhesions. AgI/II protein binds to salivary agglutinin glycoprotein, a component of tooth pellicle and to ligands in other bacteria. These associations play important roles in bacterial colonization. Recently, it was reported that diverse host molecules also interact with AgI/II protein and that these interactions induce inflammatory responses from host cells. Among mutans streptococci containing -type hemolytic activity, Streptococcus mutans is a causative agent for dental caries. Compared with many other strains of S. mutans, GS-5 strain is unique in that this bacterium expresses truncated secretory AgI/II protein due to the nonsense mutation in the agI/II gene. This indicates that S. mutans GS-5 has a different clinical role and a recent report supported this idea based on the results from clinically isolated S. mutans strains. Previously, we had cloned agI/II gene from S. mutans GS-5 and generated recombinant N-terminal AgI/II protein. In this study, we further produced a hybridoma line expressing anti-AgI/II monoclonal antibodies named as 1C11A. This antibody showed high sensitivity to AgI/II protein in Western blot and ELISA. This new reagent will provide a basis for investigating the mechanisms of AgI/II-related diseases.

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