• Title/Summary/Keyword: cell filtration system

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Improved Treatment Technique for the Reuse of Waste Solution Generated from a Electrokinetic Decontamination System (동전기제염장치에서 발생한 폐액의 재사용을 위한 개선된 처리기술)

  • Kim, Wan-Suk;Kim, Seung-Soo;Kim, Gye-Nam;Park, Uk-Ryang;Moon, Jei-Kwon
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.12 no.1
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    • pp.1-6
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    • 2014
  • A large amount of acidic waste solution is generated from the practical electrokinetic decontamination equipments for the remediation of soil contaminated with uranium. After filtration of uranium hydroxides formed by adding CaO into the waste solution, the filtrate was recycled in order to reduce the volume of waste solution. However, when the filtrate was used in an electrokinetic equipment, the low permeability of the filtrate from anode cell to cathode cell due to a high concentration of calcium made several problems such as the weakening of a fabric tamis, the corrosion of electric wire and the adhension of metallic oxides to the surface of cathode electrode. To solve these problems, sulfuric acid was added into the filtrate and calcium in the solution was removed as $CaSO_4$ precipitate. A decontamination test using a small electrokinetic equipment for 20 days indicated that Ca-removed waste solution decreased uranium concentration of the waste soil to 0.35 Bq/g, which is a similar to a decontamination result obtained by distilled water.

Real-Time RT-PCR for Validation of Reovirus Type 3 Safety During the Manufacture of Mammalian Cell Culture-Derived Biopharmaceuticals (세포배양 유래 생물의약품 생산 공정에서 Reovirus Type 3 안전성 검증을 위한 Real-Time RT-PCR)

  • Lee, Dong-Hyuck;Jeong, Hyo-Sun;Kim, Tae-Eun;Oh, Seon-Hwan;Lee, Jung-Suk;Kim, In-Seop
    • Korean Journal of Microbiology
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    • v.44 no.3
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    • pp.228-236
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    • 2008
  • Validation of viral safety is essential in ensuring the safety of mammalian cell culture-derived biopharmaceuticals, because numerous adventitious viruses have been contaminated during the manufacture of the products. Mammalian cells are highly susceptible to Reovirus type 3 (Reo-3), and there are several reports of Reo-3 contamination during the manufacture of biopharmaceuticals. In order to establish the validation system for the Reo-3 safety, a real-time RT-PCR method was developed for quantitative detection of Reo-3 in cell lines, raw materials, manufacturing processes, and final products as well as Reo-3 clearance validation. Specific primers for amplification of Reo-3 RNA was selected, and Reo-3 RNA was quantified by use of SYBR Green I. The sensitivity of the assay was calculated to be $3.2{\times}10^0\;TCID_{50}/ml$. The real-time RT-PCR method was proven to be reproducible and very specific to Reo-3. The established real-time RT-PCR assay was successfully applied to the validation of Chinese hamster ovary (CHO) cell artificially infected with Reo-3. Reo-3 RNA could be quantified in CHO cell as well as culture supernatant. When the real-time RT-PCR assay was applied to the validation of virus removal during a virus filtration process, the result was similar to that of virus infectivity assay. Therefore, it was concluded that this rapid, specific, sensitive, and robust assay could replace infectivity assay for detection and clearance validation of Reo-3.

Immuno-stimulatory Activities of a High Molecular Weight Fraction from Cynanchum wilfordii Radix Obtained by Ultrafiltration (한외거르기(Ultrafiltration)에 의하여 분리된 백수오 고분자 분획물의 면역증진 활성)

  • Jang, Mi;Lim, Tae-Gyu;Hong, Hee-Do;Rhee, Young Kyoung;Kim, Kyung-Tack;Lee, Eunjung;Lee, Jeong Hoon;Lee, Yun Ji;Kim, Yeon Bok;Cho, Chang-Won
    • Korean Journal of Food Science and Technology
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    • v.48 no.3
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    • pp.268-274
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    • 2016
  • The purpose of this study was to investigate the immuno-stimulatory activity of the high-molecular-weight fraction (HMWF) of Cynanchum wilfordii (CW) extracts obtained by ultrafiltration in murine macrophage RAW 264.7 cells and to assess its immuno-stimulatory effect in mice. Ultrafiltration was performed with polyethersulfone membranes (30 kDa cutoff) in a cross-flow filtration system to obtain the HMWF of CW. The results showed that the HMWF increased the production of various cytokines such as tumor necrosis factor-${\alpha}$, interleukin-6, and nitric oxide in dose-ependent manners. In addition, HMWF treatment increased the relative spleen weight as well as splenocyte proliferation induced by concanavalin A or bacterial lipopolysaccharide in mice. Natural killer (NK) cell activity in the HMWF-treated group was significantly increased compared to that in the control group. These results suggest that the HMWF of CW can support the immune system through secretion of macrophage cytokines, thereby enhancing NK cell activity and murine splenocyte proliferation.

Fouling Study with Binary Protein Mixtures in Microfilration (이성분계 단백질 혼합물의 미세막 분리공정에서 막오염에 관한 연구)

  • Ahn, Byung Hun;Moon, Dong Ju;Yoo, Kye Sang;Ho, Chia Chi
    • Korean Chemical Engineering Research
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    • v.43 no.2
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    • pp.236-242
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    • 2005
  • Membrane fouling by protein mixtures during microfiltration has been investigated for binary mixtures of bovine serum albumin (BSA), casein, lysozyme, pepsin, and ovalbumin. Filtration experiments were carried out using $0.2{\mu}m$ polycarbonate track-etched (PCTE) membrane in a stirred cell under constant transmembrane pressure (14 kPa) and concentration of hydrogen ion (pH=11) to study the effect of mixture composition on filtrate flux decline. Flux decline data were analyzed using a pore blockage-cake formation model developed recently. It was found that the model is in a good agreement with the experimental data. Fouling parameters such as the rate of pore blockage(${\alpha}$), the initial resistance of the protein deposit ($R_{po}$) and the increasing rate of the protein layer resistance(${\beta}$) were used to evaluate the rate of filtrate flow by membrane fouling in the binary mixture system. Generally, the trend of ${\alpha}$ is comparable with that of filtrate flux decline. It was also found that fast flux decreasing was observed over the binary mixture containing casein. The result is due to high value of the initial resistance of the protein deposit ($R_{po}$) over casein.

Does Additional Aortic Procedure Carry a Higher Risk in Patients Undergoing Aortic Valve Replacement?

  • Kim, Tae-Hun;Park, Kay-Hyun;Yoo, Jae Suk;Lee, Jae Hang;Lim, Cheong
    • Journal of Chest Surgery
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    • v.45 no.5
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    • pp.295-300
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    • 2012
  • Background: With growing attention to the aortopathy associated with aortic valve diseases, the number of candidates for accompanying ascending aorta and/or root replacement is increasing among the patients who require aortic valve replacement (AVR). However, such procedures have been considered more risky than AVR alone. This study aimed to compare the surgical outcome of isolated AVR and AVR combined with aortic procedures. Materials and Methods: A total of 86 patients who underwent elective AVR between 2004 and June 2010 were divided into two groups: complex AVR (n=50, AVR with ascending aorta replacement in 24 and the Bentall procedure in 26) and simple AVR (n=36). Preoperative characteristics, surgical data, intra- and postoperative allogenic blood transfusion requirement, the postoperative clinical course, and major complications were retrospectively reviewed and compared. Results: The preoperative mean logistic European System for Cardiac Operative Risk Evaluation (%) did not differ between the groups: $11.0{\pm}7.8%$ in the complex AVR group and $12.3{\pm}8.0%$ in the simple AVR group. Although complex AVR required longer cardiopulmonary bypass ($152.4{\pm}52.6$ minutes vs. $109.7{\pm}22.7$ minutes, p=0.001), the quantity of allogenic blood products did not differ ($13.4{\pm}14.7$ units vs. $13.9{\pm}11.2$ units). There was no mortality, mechanical circulatory support, stroke, or renal failure requiring hemodialysis/filtration. No difference was found in the incidence of bleeding (40% vs. 33.3%) which was defined as red blood cell transfusion ${\geq}5$ units, reoperation, or intentional delayed closure. The incidence of mediastinitis (2.0% vs. 0%), ventilator ${\geq}24$ hours (4.0% vs. 2.8%), atrial fibrillation (18.0% vs. 25.0%), mean intensive care unit stay (34.5 hours vs. 38.8 hours), and median hospital stay (8 days vs. 7 days) did not differ, either. Conclusion: AVR combined with additional aortic or root replacement showed an excellent outcome and recovery course equivalent to that after isolated AVR.

A Study on Location Selection for Rainwater Circulation System Elements at a City Level - Focusing on the Application of the Environmental and Ecological Plan of a Development - (도시차원의 빗물순환체계 요소별 입지선정에 관한 연구 - 개발예정지역의 환경생태계획 적용방안을 중심으로 -)

  • Kim, Hyo-Min;Kim, Kwi-Gon
    • Journal of the Korean Institute of Landscape Architecture
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    • v.40 no.3
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    • pp.1-11
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    • 2012
  • This study focused on establishing a natural rainwater circulation system using rainwater meant for relatively large urban development projects such as a new town development. In particular, when the location selection techniques for individual elements of a natural rainwater circulation system are developed for the integrated rainwater management, changes in hydrological environment will be minimized and the natural water circulation would be restored to realize the low impact development (LID). In that case, not only the excess will be reduced but water space and green areas in a city would also increase to improve the urban sustainability. First of all, there were five elements selected for the location selection of a rainwater circulation system intended for the integrated rainwater management: rainwater collection, infiltration, filtration, retention and movement spaces. After generating these items, the location selection items and criteria were defined for each of the five elements. For a technique to apply the generated evaluation items and criteria, a grid cell analysis was conducted based m the suitability index theory, and thematic maps were overlapped through suitability assessment of each element and graded based on the suitability index. The priority areas were identified for each element. The developed technique was applied to a site where Gim-cheon Innovation City development is planned to review its feasibility and limitations. The combined score of the overlapped map for each element was separated into five levels: very low, low, moderate, high and very high. Finally, it was concluded that creating a rainwater circulation system conceptual map m the current land use plan based on the outcome of the application would be useful in building a water circulation system at the de1ailed space planning stage after environmental and ecological planning. Furthermore, we use the results of this study as a means for environment-friendly urban planning for sustainable urban development.