• BMB Reports
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• v.28 no.4
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• pp.331-335
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• 1995

Simian virus 40 (SV40) small-t antigen (small-t) has been known to regulate the activity of a cellular enzyme, protein phosphatase 2A (PP2A), composed of A. B, and C subunits, via binding to the A subunit In the study presented here, the stoichiometry of the binding of small-t to PP2A was determined to be 1: 1. It was also shown that small-t binds to the AC form of PP2A with a higher apparent affinity than it binds to the free A subunit. We also characterized the interaction of PP2A with wild-type and various mutant small-ts. A single-point mutant (Val134Met) and a double-point mutant (Trp147Gly;Leu152 Pro) of small-t exhibited 3-fold and 5-fold lower potencies in inhibiting PP2A activity. respectively. This suggests that the region around amino acids between 134 and 152 of small-t might be important in regulating the enzyme activity of PP2A.

• Molecular & Cellular Toxicology
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• v.5 no.1
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• pp.32-43
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• 2009

Acetaminophen (APAP) overdose is known to cause severe hepatotoxicity mainly through the depletion of glutathione. In this study, we compared the cytotoxic effects of APAP on both a normal murine hepatic cell line, BNL CL.2, and its SV40-transformed cell line, BNL SV A.8. Gene expression profiles for APAP-treated cells were also obtained using microarray and analyzed to identify differences in genes or profiles that may explain the differences of susceptibility to APAP in these cell lines. These two cell lines exhibited different susceptibilities to APAP (0-$5,000{\mu}M$); BNL SV A.8 cells were more susceptible to APAP treatment compared to BNL CL.2 cells. A dose of $625{\mu}M$ APAP, which produced significant differences in cytotoxicity in these cell lines, was tested. Microarray analysis was performed to identify significant differentially expressed genes (DEGs) irrespective of APAP treatment. Genes up-regulated in BNL SV A.8 cells were associated with immune response, defense response, and apoptosis, while down-regulated genes were associated with catalytic activity, cell adhesion and the cytochrome P450 family. Consistent with the cytotoxicity data, no significant DEGs were found in BNL CL.2 cells after treatment with $625{\mu}M$ APAP, while cell cycle arrest and apoptosis-related genes were up-regulated in BNL SV A.8 cells. Based on the significant fold-changes in their expression, a genes were selected and their expressions were confirmed by quantitative real-time RT-PCR; there was a high correlation between them. These results suggest that gene expression profiles may provide a useful method for evaluating drug sensitivity of cell lines and eliciting the underlying molecular mechanism. We further compared the genes identified from our current in vitro studies to the genes previously identified in our lab as regulated by APAP in both C57BL/6 and ICR mice in vivo. We found that a few genes are regulated in a similar pattern both in vivo and in vitro. These genes might be useful to develop as in vitro biomarkers for predicting in vivo hepatotoxicity. Based on our results, we suggest that gene expression profiles may provide useful information for elucidating the underlying molecular mechanisms of drug susceptibility and for evaluating drug sensitivity in vitro for extrapolation to in vivo.

• Journal of the Korean Magnetics Society
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• v.20 no.2
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• pp.35-40
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• 2010

The GMR-SV (giant magnetoresistance-spin valve) device depending on the micro patterned features according to two easy directions of longitudinal and transversal axes has been studied. The GMR-SV multilayer structure was Ta(5 nm)/NiFe(8 nm)/Cu(2.3 nm)/NiFe(4 nm)/IrMn(8 nm)/Ta(2.5 nm). The applied anisotropy direction of the GMR-SV thin film was performed under the magnitude of 300 Oe using by permanent magnet during the deposition. The size of micro patterned device was a $1\;{\times}\;18\;{\mu}m^2$ after the photo lithography process. In the aspects of the shape magnetic anisotropy effect, there are two conditions of fabrication for GMR-SV device. Firstly, the direction of sensing current was perpendicular to the magnetic easy axis of the pinned NiFe/IrMn bilayer with the transversal direction of device. Secondly, the direction of shape magnetic anisotropy was same to the magnetic easy axis of the free NiFe layer with the longitudinal direction of device.

• Korean Journal of Food Science and Technology
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• v.40 no.6
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• pp.633-642
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• 2008

Several domestic new varieties of grapes were utilized for the fermentation of wines, including Cabernet Sauvignon, NY 21576, Canner, SV 18315, Agawan, and Black Bagal red wines, and Naples, Aligote, and Alicante white wines. The oBx values of the grapes ranged between 17 and $20^{\circ}Bx$. Soluble solid content was adjusted to $21^{\circ}Bx$ by adding sugar for all grapes and fermented at $20^{\circ}C$ for 2 weeks. Black Bagal and Cabernet Sauvignon were relatively slower than other grapes with regard to alcohol production rate. The L value of wine made from Agawan and NY 21576 were lower and darker than those of wines prepared from other grapes. Wine made from NY 21576 grapes had a polyphenol concentration of 1.40 mg/mL, which was higher than that of any other wine, whereas wines made from MBA and all white wines evidenced value of only 0.55 mg/mL and 0.15 mg/mL, respectively, after 2 weeks of fermentation. The sensory evaluations demonstrated that the quality of red wines made from NY 21576, Cabernet Sauvignon, Black Bagal, and that of white wines made from Naples grapes were favorable among the different grape variants.

• Structural Monitoring and Maintenance
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• v.9 no.1
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• pp.43-57
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• 2022

One of the instances which demand structural engineer's greatest attention and upgradation is the changing live load requirement in bridge design code. The challenge increases in developing countries as the pace of infrastructural growth is being catered by the respective country codes with bigger and heavier vehicles to be considered in the design. This paper presents the case study of India where Indian Roads Congress (IRC) codes in its revised version from 2014 to 2017 introduced massive Special vehicle (SV) around 40 m long and weighing 3850 kN to be considered in the design of road bridges. The code does not specify the minimum distance between successive special vehicles unlike other loading classes and hence the consequences of it form the motivation for this study. The effect of SV in comparison with Class 70R, Class AA, Class A, and Class B loading is studied based on the maximum bending moment with moving load applied in Autodesk Robot Structural Analysis. The spans considered in the analysis varied from 10 m to 1991 m corresponding to the span of Akashi Kaikyo Bridge (longest bridge span in the world). A total of 182 analyses for 7 types of vehicles (class B, class A, class 70R tracked, class 70R wheeled, class AA tracked, AA wheeled, and Special vehicle) on 26 different span lengths is carried out. The span corresponding to other vehicles which would equal the bending moment of a single SV is presented along with a comparison relative to Standard Uniformly Distributed Load. Further, the results are presented by introducing a new parameter named Intensity Factor which is proven to relate the effect of axle spacing of vehicle on the normalized bending moment developed.

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2003.10a
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• pp.122-122
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• 2003

• The Science & Technology
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• v.30 no.4 s.335
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• pp.49-50
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• 1997

동물복제ㆍ인간복제로 떠들썩한 요즈음 우리나라에서 유전공학 바람을 일으키는 주축으로 활약하고 있는 서울대 자연대 미생물학과 강현삼교수. 강교수는 원숭이에서 암을 유발시키는 SV40 바이러스가 가진 암유발유전자와 형질 변형시킨 사람의 각질세포를 이용한 조직배양 실험을 통해 인슐린 등 생존요소를 투입할 경우 아폽토시스 과정을 촉진시켜 암을 억제할 수 있다는 논문을 발표해 관심을 끌고 있다.

• Korean Journal of Digital Imaging in Medicine
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• v.14 no.2
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• pp.23-31
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• 2012

There are AEC mode and fix mode to exposure when the whole spine antero-posterior radiography is done by using DR equipment. This study compared the utility of fix mode to AEC mode, by evaluating organ dose and effective dose and by examining the quality of radiographic image. GE DEFINIUM 8000 and ART-200X Rando Phantom manufactured by Flukebiometical were used for this study. The Rando phantom was set in front of wall detector of X-rays equipment. AEC mode was set at 80kVp and Fix mode was set at 80kVp, 25mAs, 32mAs, 40mAs, and 50mAs. Whole spine AP image were aquired by combining C, T-L and L-S spine images obtained through 3 exposures. When obtaining C, T-L and L-S spine images, were checked for Air kerma (mGy) value calculated by UNFORS Xi meter attached at the phantom surface of center of radiation field. The effective and organ doses were compared by PCXMC program (PC-Based Monte Carlo Program). The quality of obtained radiographic image was evaluated visually by 3 radiologists using resolution chart. When the effective doses was calculated based on tissue weighting factor of ICRP-103, 1.278mSv was measured by AEC mode, and Fix mode measured 0.405mSv at 25mAs, 0.518mSv at 32mAs, 0.649mSv at 40mAs, and 0.810mSv at 50mAS. In addition, the organ dose measured with esposure at 25mAs by Fix mode was almost equivalent to the organ dose by AEC mode, at the esophagus, thyroid, oral mucosa, salivaly glands located at the cervical spine part, while the organ dose by Fix mode was in general lower than the organ dose by AEC mode at the other organs. When Fix mode at 32mAs, 40mAs, and 50mAs was compared to AEC mode for organ dose in 26 organs, AEC mode had higher measurement in 21 organs but not for than brain, trachea, thyroid, oral mucosa, and salivaly glands which are located at the cervical spine part. The image quality evaluated by resolution test chart was much higher with AEC mode than the quality with Fix mode at all exposure conditions. However, while the image quality of cervical spine exposured at 50mAs by Fix mode was lower than the quality of AEC mode, thoraco-lumbar spine and lumbo-sacral spine were calculated and the quality was similar to AEC mode. Scoliosis occurs mainly at thoraco-lumbar and lumbo-sacral spine, not at cervical spine. Compared to AEC mode, Using the appropriate protocol (80kVp, 50mAs) of fix mode for whole spine AP radiography was thought to be useful because the image quality of the thoraco-lumar and lumbo-sacral spine was similar on AEC mode, Also organ and effective doses can be decreased with Fix mode. Therefore, It is considered that fix mode can be used properly with AEC mode for whole spine AP radiography when considering patient's body posture.

• Journal of radiological science and technology
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• v.23 no.1
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• pp.13-19
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• 2000

We have presented with the "A study on overexposure rate according to over-density in chest X-ray radiography(I)" last year. In this report, We could calculate the entrance skin dose from chest X-ray film density the formula $I_0=Ix/e^{-{\mu}x}{\times}mG$, (mG is Bucky factor) was used to deliver the skin dose. At that time, There was two problems that the Bucky factor from maker was not equal to field experience and the field size influenced on the Attenuation Rate. The experiment of Bucky factor was done from film method and retried the Attenuation Rate of Acryle phantom according to Good & Poor geometry. As the results, The Bucky factor from maker higher than in this experiments $30{\sim}40%$. The Attenuation Rate in good geometric condition brings about a little alteration compare with poor geometric condition. In the field experiment, we could get the chest image with very low entrance skin radiation dose $29.3{\mu}Sv$, especially with air gap methode, the entrance skin dose was detected $10{\mu}Sv$.

• Journal of Radiation Protection and Research
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• v.47 no.4
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• pp.204-213
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• 2022

Background: The accident at the Fukushima Daiichi nuclear power plant increased the level of anxiety related to the radioactive contamination of various foods sourced in Japan. Particularly, after the accident, the detection of artificial radionuclides in locally produced foods raised food safety concerns. In this study, the radioactivity concentrations and annual ingestions of ⁴⁰K and ¹³⁷Cs in food products commonly and frequently consumed by the general public were investigated, and the annual effective dose of each was evaluated. Materials and Methods: The 2016-2018 data from the Radiation Safety Management Report released by the Korea Nuclear Safety Technology Center was referenced for the evaluation of the amounts of ⁴⁰K and ¹³⁷Cs contained in food. Using the food-ingestion survey mentioned above as a reference, we selected 62 foods to include in our radioactivity concentration and dose assessment. We also developed a questionnaire and evaluated the responses from the subjects who answered the questionnaire. Results and Discussion: The radioactivity concentration of ¹³⁷Cs was found to be close to or below the level of minimum detectable activity. Additionally, the annual ingestion of 62 foods was 294.77 kg/yr, the effective doses from ⁴⁰K and ¹³⁷Cs were 136.4 and 0.163 μSv/yr, respectively. Conclusion: Thus, the findings confirmed that the effective dose from ⁴⁰K and ¹³⁷Cs in food tends to be lower than the effective dose limit of 1 mSv/yr suggested by the International Commission on Radiological Protection (ICRP) Publication 60. The questionnaire developed in this study is expected to be useful for estimating the annual effective dose status of Korean adults who consume foods containing ⁴⁰K and ¹³⁷Cs.