• Title/Summary/Keyword: Radiation dose effect

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Inhibition of Production of Reactive Oxygen Species and Gene Expression Profiles by Cirsii Japonici Herba Extract Treatment in HepG2 Cells

  • Rho, Sam-Woong;Chung, Hwan-Suck;Kang, Moon-Kyu;Na, Young-In;Cho, Chong-Woon;Kim, Hyung-Min;Jung, Hyuk-Sang;Park, Hi-Joon;Kim, Hong-Yeoul;Hong, Moo-Chang;Shin, Min-Kyu;Kim, Sung-Soo;Bae, Hyun-Su
    • Molecular & Cellular Toxicology
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    • v.1 no.4
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    • pp.224-229
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    • 2005
  • Cirsii Japonici Herba (CJH) extract has been used for hundreds of years in Asian countries as a treatment for pollutant, radiation, and alcohol-induced liver damage. The reducing effect of CJH on hydrogen peroxide-induced reactive oxygen species (ROS) production, the main cause of cell damage or death, was evaluated using the HepG2 cell line. Cell survival was determined using MTS assay. The viability of cells treated with CJH was not significantly different from oxidative-stressed HepG2 cells. A dose-dependent inhibitory effect by CJH on ROS production was shown in oxidative-stressed cells using the $H_{2}DCFDA$ assay. To identify candidate genes responsible for the anti-oxidative effects of CJH on HepG2 cells, an oligonucleotide microarray analysis was performed. The expressions of five genes were decreased, whereas nineteen genes were up-regulated in CJH plus hydrogen peroxide treated cells, compared to only hydrogen peroxide treated cells. Among them, the expression of 5 genes was decreased in hydrogen peroxide treatment when compared to control. These genes are known to regulate cell survival and progression. On the other hand, it was shown that its main compounds were not a sylimarin or its analogs. The list of differentially expressed genes may provide further insight on the action and mechanism behind the anti-oxidative effects of Cirsii Japonici Herba.

Cellular Protective Effect and Liposome Formulation for Enhanced Transdermal Delivery of Persicaria hydropiper L. Extract (여뀌 추출물의 세포 보호 작용과 피부 흡수 증진을 위한 리포좀 제형 연구)

  • Kim, Jung-Eun;Lee, Hye-Jin;Lim, Myoung-Sun;Park, Min-A;Park, Soo-Nam
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.38 no.1
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    • pp.15-31
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    • 2012
  • In our previous studies, the antioxidant, anti-aging, and antibacterial activities of Persicaria hydropipier L. extract, and the moisturizing effect of cream containing P. hydropipier extract were investigated. In this study, the cellular protective effects of P. hydropipier extract and isoquercitrin, main component from P. hydropipier in $^1O_2$-induced photohemolysis of human erythrocytes and ultraviolet B (UVB)-exposed HaCaT cells were investigated. Liposomes such as ethosome and elastic liposome for enhanced transdermal delivery were prepared. Size, loading efficiency, stability, and cumulative permeated amounts of ethosomes and elastic liposomes were evaluated. P. hydropipier extract and isoquercitrin showed more prominent cellular protective effect than (+)-${\alpha}$-tocopherol, known as lipid antioxidant at $5{\mu}g/mL$. P. hydropipier extract didn't show any characteristics of cytotoxicity at $50{\mu}g/mL$. When HaCaT cells were exposed to a single large dose ($400mJ/cm^2$) of UVB, the extract protected the cells against UVB radiation in a concentration dependent manner ($12.5{\sim}50{\mu}g/mL$). Cell viability of HaCaT cells exposed to UVB $400mJ/cm^2$ was increased by treatment with P. hydropipier extract or isoquercitrin from 36 % (cell viability of positve control groups) to 90 % (cell viability of P. hydropipier extract or isoquercitrin- treated groups). The size of 0.04 % P. hydropiper extract loaded ethosomes was 173.0 nm and the loading efficiency was 55.58 %. 0.04 % P. hydropiper extract loaded ethosomes were stable with as monodisperse particles for 1 week. The ethosome exhibited more skin permeability than general liposome and ethanol solution. The optimal ratio of lipid to surfactant ($Tego^{(R)}$ care 450) of 0.1 % P. hydropiper extract loaded elastic liposomes was observed to be 95 : 5. Vesicle size of 0.1 % P. hydropiper extract loaded elastic liposome was 176.5 nm. The deformability index of the elastic liposome was 16.4. The loading efficiency was 68.8 %. The elastic liposome containing P. hydropiper extract showed more skin permeability than liposome without surfactant ($Tego^{(R)}$ care 450).

Induction Chemotherapy and Radiotherapy in Locally Advanced Non-Small Cell Lung Cancer (NSCLC) (국소 진행된 비소세포성 폐암에서 유도 화학요법 및 방사선치료)

  • Yun, Sang-Mo;Kim, Jae-Cheol;Park, In-Kyu
    • Radiation Oncology Journal
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    • v.17 no.3
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    • pp.195-202
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    • 1999
  • Purpose : We peformed this study to evaluate the prognostic factors and the effect of induction chemotherapy in locally advanced non-small cell lung cancer (NSCLC). Materials and Methods : A retrospective analysis was done for 130 patients with locally advanced NSCLC treated with curative radiotherapy alone or induction chemo-radiotherapy from January 1986 to October 1996. Eighty-five patients were treated with radiotherapy alone, forty-five with induction chemotherapy and radiotherapy. Age, sex, performance status, histopathologic type, and stage were evenly distributed in both groups. The patients were treated with 6 MV or 10 MV X-ray. Conventional fractionation with daily fraction size 1$.8\~2.0$ Gy was done. Of the patients, 129 patients received total dose above 59.6 Gy ($56\~66$ Gy, median 60 Gy). Induction chemotherapy regimen were CAP (Cyclo-phosphamide, Adriamycin, Cisplatin) in 6 patients, MVP (Mitomycin, Vinblastine, Cisplatin) in 9 patients, MIC (Mitomycin, Ifosfamide Cisplatin) in 13 patients, and EP (Etoposide, Cisplatin) in 17 patients. Chemotherapy was done in $2\~5$ cycles (median 2). Results : Overall 1-, 2-, and 3-year survival rate (YSR) for all patients were $41.5\%,{\;}13.7\%,{\;}and{\;}7\%$, respectively (median survival time 11 months). According to treatment modality, median survival time, overall 1-, 2-, and 3-YSR were 9 months, $32.9\%,{\;}10.\5%,{\;}6\%$ for radiotherapy alone group, and 14 months, $57.8\%,{\;}20\%,{\;}7.6\%$ for induction chemotherapy group, respectively (f=0.0005). Complete response (CR) to overall treatments was $25\%$ (21/84) in radiotherapy alone and $40.5\%$ (17/42) in induction chemotherapy group (p=0.09). The Prognostic factors affecting overall survival were hemoglobin level (p=0.04), NSE (neuron-specific enolase) level (p=0.004), and respense to overall treatment(p=0.004). According to treatment modalities, NSE (neuron-specific enolase) (p=0.006) and response to overall treatment (p=0.003) were associated with overall survival in radiotherapy alone group, and response to overall treatment (p=0.007) in induction chemotherapy group. The failure Pattern analysis revealed no significant difference between treatment modalities. But, in patients with CR to overall treatment, distant metastasis were found in 11/19 patients with radiotherapy alone, and 3/13 patients with induction chemotherapy and radiotherapy (p=0.07). Locoregional failure patterns were not different between two groups (10/19 vs 6/13). Conclusion : Induction chemotherapy and radiotherapy achieved increased 2YSR compared to radiotherapy alone, At least in CR patients, there was decreased tendency in distant metastasis with induction chemotherapy. But, locoregional failures and long-term survival were not improved. Thus, there is need of more effort to increasing local control and further decreasing distant metastasis.

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Effects of Contrast Improvement on High Voltage Rectification Type of X-ray Diagnostic Apparatus (X선 진단장치의 고압정류방식이 대조도 향상에 미치는 영향)

  • Lee, Hoo-Min;Yoon, Joon;Kim, Hyun-Ju
    • Journal of radiological science and technology
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    • v.37 no.3
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    • pp.187-193
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    • 2014
  • The purpose of this study was to analyze the effect on the selectivity on of high-voltage rectification device that measured the performance of the grid, and the contrast improvement ability (K factor) by measuring the scattered radiation content of the transmitted X-rays. The scattered radiation generated when the X-ray flux comes from the diagnostic X-ray generator that passes through an object. Targeting four different rectifications of X-ray generators, the mean value of the tube voltage and the tube current was measured in order to maximize the accuracy of the generating power dose within the same exposure condition. Using fluorescence meter, the content of the scattered rays that are transmitted through the acrylic was measured depending on the grid usage. When grid is not used, the content of the scattered rays was the lowest (34.158%) with the single-phase rectifier, was increased with the inverter rectifier (37.043%) and the three-phase 24-peak rectification method (37.447%). The difference of the scattered radiation content of each device was significant from the lowest 0.404% to the highest 3.289% while using 8:1 grid, the content of the scattered ray was the lowest with the single content of the scattered ray was the lowest with the single-phase rectifier (18.258%), was increased with the rectifier (25.502%) and the 24-peaks rectification (24.217%). Furthermore, there was difference up to content 7.244% to the lowest content 1.285% within three-phase 24-peaks rectification, inverter rectifications, and single-phase rectifier depending on the selectivity of the grid. Drawn from the statistical analysis, there was a similar relationship between the contrast improvement factor and the K factor. As a result, the grid selectivity and the contrast were increased within the single-phase rectifier rather than the constant voltage rectifier.

Evaluation of Radiation Shielding Rate of Lead Aprons in Nuclear Medicine (핵의학과에서 사용하는 납 앞치마의 방사선 차폐율 평가)

  • Han, Sang-Hyun;Han, Beom-Heui;Lee, Sang-Ho;Hong, Dong-Heui;Kim, Gi-Jin
    • Journal of radiological science and technology
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    • v.40 no.1
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    • pp.41-47
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    • 2017
  • Considering that the X-ray apron used in the department of radiology is also used in the department of nuclear medicine, the study aimed to analyze the shielding rate of the apron according to types of radioisotopes, thus ${\gamma}$ ray energy, to investigate the protective effects. The radioisotopes used in the experiment were the top 5 nuclides in usage statistics $^{99m}Tc$, $^{18}F$, $^{131}I$, $^{123}I$, and $^{201}Tl$, and the aprons were lead equivalent 0.35 mmPb aprons currently under use in the department of nuclear medicine. As a result of experiments, average shielding rates of aprons were $^{99m}Tc$ 31.59%, $^{201}Tl$ 68.42%, and $^{123}I$ 76.63%. When using an apron, the shielding rate of $^{131}I$ actually resulted in average dose rate increase of 33.72%, and $^{18}F$ showed an average shielding rate of -0.315%, showing there was almost no shielding effect. As a result, the radioisotopes with higher shielding rate of apron was in the descending order of $^{123}I$, $^{201}Tl$, $^{99m}Tc$, $^{18}F$, $^{131}I$. Currently, aprons used in the nuclear medicine laboratory are general X-ray aprons, and it is thought that it is not appropriate for nuclear medicine environment that utilizes ${\gamma}$ rays. Therefore, development of nuclear medicine exclusive aprons suitable for the characteristics of radioisotopes is required in consideration of effective radiation protection and work efficiency of radiation workers.

Antioxidant and Neuroprotective Effects of Green Tea Seed Shell Ethanol Extracts (녹차씨껍질 에탄올 추출물의 항산화 활성 및 신경세포 보호 효과)

  • Sung, Nak-Yun;Song, Hayeon;Ahn, Dong-Hyun;Yoo, Yung-Choon;Byun, Eui-Baek;Jang, Beom-Su;Park, Chulhwan;Park, Won-Jong;Byun, Eui-Hong
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.7
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    • pp.958-965
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    • 2016
  • The objective of this study was to evaluate the antioxidant activity of green tea seed shell as an industrial byproduct. Green tea seed shell extract (GTSSE) was obtained by ethanol extraction, and the yield was $1.4{\pm}0.22%$. The radical scavenging activities [1,1-diphenyl-picrylhydrazyl and 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid)], xanthine oxidase inhibition activity, and reducing power of GTSSE dose-dependently increased. To estimate the neuroprotective effect of GTSSE, viability was tested in HT22 mouse hippocampal cells. GTSSE treatment induced cytotoxicity at a concentration higher than $100{\mu}g/mL$ but not at a concentration lower than $50{\mu}g/mL$. Using this optimal concentration range, GTSSE treatment significantly increased cell viability in $H_2O_2$-treated HT22 cells. Further, GTSSE treatment increased superoxide dismutase activity and decreased the malonaldehyde level, a product of lipid peroxidation, in HT22 cells. Therefore, these results indicate that green tea seed shell extract may be useful for the development of antioxidant materials and have potential activity to prevent and treat neuro-degenerative diseases such as Alzheimer's disease.

Comparison Evaluation of Image Quality with Different Thickness of Aluminum added Filter using GATE Simulation in Digital Radiography (GATE 시뮬레이션을 사용한 알루미늄 부가필터 두께에 따른 Digital Radiography의 영상 화질 비교 평가)

  • Oh, Minju;Hong, Joo-Wan;Lee, Youngjin
    • Journal of the Korean Society of Radiology
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    • v.13 no.1
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    • pp.81-86
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    • 2019
  • In X-ray image, the role of filtration through the filter is to reduce the exposure of the patient by using photon which is useful in formation of the image, and at the same time, enhance the contrast of the image. During interaction between photon and object, low energy X-rays are absorbed from the site of a few cm of the first patient's tissue, and high energy X-rays are the one which form the image. Therefore, the radiation filter absorbs low energy X-ray in order to lower the exposure of the patient and improve the quality of the image. The purpose of this study is to compare the effect on the image quality by differences of added filter through simulation image and actual radiation image. For that purpose, we used Geant4 Application for Tomographic Emission (GATE) as a tool for Monte Carlo simulation. We set actual size, shape and material of Polymethylmethacrylate (PMMA) Phantom on GATE and differentiated the parameter of added filter. Also, we took image of PMMA phantom with same parameter of added filter by digital radiography (DR). Than we performed contrast-to-noise ratio (CNR) evaluation on both simulation image and actual DR image by Image J. Finally, we observed the effect on image quality due to different thickness of added filter, and compared two images' CNR evaluation's transitions of change. The result of this experiment showed decreasing in the progress of CNR on both DR and simulation image. It is ultimately caused by decreasing in contrast on image. In theory, contrast decrease with kVp increased. Given that condition, this study found out that filter makes not only decreasing total dose by absorbing low energy of X-ray, but also increasing average energy of X-ray.

Effect of Radiation Dosage Changes on the Cell Viability and the Apoptosis Induction on Normal and Tumorigenic Cells (방사선의 선량변화가 수종의 정상세포와 종양세포주의 세포활성도와 apoptosis 유발에 미치는 영향)

  • Park In-Woo;Lee Sam-Sun;Heo Min-Suk;Choi Soon-Chul
    • Journal of Korean Academy of Oral and Maxillofacial Radiology
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    • v.29 no.2
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    • pp.435-449
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    • 1999
  • Purpose : The study was aimed to detect the differences in the cell viability and the apoptosis induction after irradiation on normal and tumorigenic cells. Materials and Methods : The study. that was generated for two human normal cells(RHEK, HGF-l) and two human tumor cells(KB. HT-1080). was tested using MTT assay at 1 day and 3 day after irradiation and TUNEL assay under confocal laser scanning microscope at 1 day after irradiation. Single irradiation of 0.5. 1, 2. 4. and 8Gy were applied to the cells. The two fractions of 1. 2. 4. and 8Gy were separated with a 4-hour time interval. The irradiation was done with 5.38Gy/min dose rate using Cs-137 irradiator at room temperature. Results and Conclusions : 1. In 3-day group. the cell viability of HGF-1 cell was significantly decreased at 2. 4 and 8Gy irradiation, the cell viability of KB cell was significantly decreased at 8Gy irradiation and the cell viability of HT-I080 cell was significantly decreased at 4 and 8Gy irradiation. 2. There was significant difference between RHEK and KB cell line in the cell viability of 3-day group at 8Gy irradiation. There was significant difference between RHEK and HGF-1 cell line in the cell viability of 3-day group at 4 and 8Gy irradiation. 3. There was a significantly decreased cell viability in 3-day group than those in 1-day group at 2. 4 and 8Gy on HGF-1 cell. at 4 and 8Gy on HT-I080 cell. at 8Gy on KB cell. 4. We could detect DNA fragmented cells only on KB cell. Number of apoptotic cells of KB cell was significantly increased at 4 and 8Gy irradiation. However, there was no correlation between cell viability and apoptosis. 5. On all 4 cell lines, there were no differences between single and split irradiation method in cell viability and apoptosis.

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Cytotoxic Effects of Decursin from Angelica gigas Nakai in Human Cancer Cells (당귀로부터 정제한 Decursin의 인체암세포주에 대한 세포독성)

  • Park, Kyung-Wuk;Choi, Sa-Ra;Shon, Mi-Yae;Jeong, Il-Yun;Kang, Kap-Suk;Lee, Sung-Tae;Shim, Ki-Hwan;Seo, Kwon-Il
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.36 no.11
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    • pp.1385-1390
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    • 2007
  • Anticarcinogenic-active compound was isolated and purified from Angelica gigas Nakai. The compound was identified as decursin ($C_{19}H_{20}O_5$; molecular weight 328) by mass, IR spectrophotometry $^1H-NMR$ and $^{13}C-NMR$. The proliferation decreased in a dose dependant fashion in the MCF-7 cells treated with decursin for 24 hours over the concentration of $20{\mu}g/mL$. The $IC_{50}$ value of the decursin treatment for 24 hours were 31.04, 33.60, 27,24, $20.45{\mu}g/mL$ in the SW480, 293, HepG2 and MCF-7 cells, respectively, The growth inhibitory effect was stronger in the MCF-7 cells compared to other cells including 293 of human normal cells. The chromatin condensation, apoptotic body formation and DNA fragmentation were examined in the cells treated with decursin. These results suggest that decursin from Angelica gigas Nakai inhibited the growth through apoptosis in MCF-7 cells.

Inactivation of Xanthomonas citri subsp. citri and Effect on Infection of Citrus Canker by Gamma Irradiation (감마선에 의한 감귤 궤양병균의 불활성화와 감귤 궤양병 감염에 미치는 영향)

  • Kim, Kyung Nam;Song, Min A;Han, Sang Heon;Song, Seong Joon;Jeun, Yong Chull
    • Research in Plant Disease
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    • v.20 no.4
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    • pp.283-288
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    • 2014
  • Citrus canker caused by Xanthomonas citri subsp. citri (Xcc) has been quarantined by many countries in the world. Recently, the usage of methyl bromide should be limited, application by gamma irradiation on the agricultural production is raised as an alternative method. In this study, the level of gamma irradiation which could decrease of population of Xcc in the suspension or on the surface of citrus fruit was investigated. The $D_{10}$ value of Xcc, which is radiation dose required to reduce the number of the microorganism, was 55 and 28 Gy in the suspension and on the surface of citrus fruit, respectively. Furthermore, disease severity was suppressed on the citrus leaves inoculated with Xcc suspension pre-treated with gamma irradiation. Based on this study, it is suggested that Xcc on the citrus fruit could be eradicated by gamma irradiation and the results of this study may be valuable for application of gamma ray in quarantine activity.