• Title/Summary/Keyword: beta radiation

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Molecular biomarkers in extrahepatic bile duct cancer patients undergoing chemoradiotherapy for gross residual disease after surgery

  • Koh, Hyeon Kang;Park, Hae Jin;Kim, Kyubo;Chie, Eui Kyu;Min, Hye Sook;Ha, Sung W.
    • Radiation Oncology Journal
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    • v.30 no.4
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    • pp.197-204
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    • 2012
  • Purpose: To analyze the outcomes of chemoradiotherapy for extrahepatic bile duct (EHBD) cancer patients who underwent R2 resection or bypass surgery and to identify prognostic factors affecting clinical outcomes, especially in terms of molecular biomarkers. Materials and Methods: Medical records of 21 patients with EHBD cancer who underwent R2 resection or bypass surgery followed by chemoradiotherapy from May 2001 to June 2010 were retrospectively reviewed. All surgical specimens were reevaluated by immunohistochemical staining using phosphorylated protein kinase B (pAKT), CD24, matrix metalloproteinase 9 (MMP9), survivin, and ${\beta}$-catenin antibodies. The relationship between clinical outcomes and immunohistochemical results was investigated. Results: At a median follow-up of 20 months, the actuarial 2-year locoregional progression-free, distant metastasis-free and overall survival were 37%, 56%, and 54%, respectively. On univariate analysis using clinicopathologic factors, there was no significant prognostic factor. In the immunohistochemical staining, cytoplasmic staining, and nuclear staining of pAKT was positive in 10 and 6 patients, respectively. There were positive CD24 in 7 patients, MMP9 in 16 patients, survivin in 8 patients, and ${\beta}$-catenin in 3 patients. On univariate analysis, there was no significant value of immunohistochemical results for clinical outcomes. Conclusion: There was no significant association between clinical outcomes of patients with EHBD cancer who received chemoradiotherapy after R2 resection or bypass surgery and pAKT, CD24, MMP9, survivin, and ${\beta}$-catenin. Future research is needed on a larger data set or with other molecular biomarkers.

Survey of Biogenic Amines Contents in Commercial Beers (시판 맥주 중의 biogenic amines 함량 조사)

  • Kim, Jae-Hyun;Ahn, Hyun-Joo;Hong, Jin-Hwan;Han, Sang-Bae;Byun, Myung-Woo
    • Korean Journal of Food Science and Technology
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    • v.34 no.6
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    • pp.1127-1129
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    • 2002
  • Fourteen commercial beers (eight domestic and six imported) were investigated for their biogenic amine contents. In all products, six biogenic amines, putrescine, cadaverine, tryptamine, ${\beta}-phenylethylamine$, spermine, and tyramine, were detected at different contents among the products, with the spermine content being the highest. Contents of cadaverine and ${\beta}-phenylethylamine$ in domestic beers, and ${\beta}-phenylethylamine$ and tyramine in imported ones were not significantly different. Results indicate that continuous monitoring of biogenic amine levels in commercial beers is needed to maintain chemical safety and qualities.

Feasibility Study of Beta Detector for Small Leak Detection inside the Reactor Containment

  • Jang, JaeYeong;Schaarschmidt, Thomas;Kim, Yong Kyun
    • Journal of Radiation Protection and Research
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    • v.43 no.4
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    • pp.154-159
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    • 2018
  • Background: To prevent small leakage accidents, a real-time and direct detection system for small leaks with a detection limit below that of existing systems, e.g. $0.5gpm{\cdot}hr^{-1}$, is required. In this study, a small-size beta detector, which can be installed inside the reactor containment (CT) building and detect small leaks directly, was suggested and its feasibility was evaluated using MCNPX simulation. Materials and Methods: A target nuclide was selected through analysis of radiation from radionuclides in the reactor coolant system (RCS) and the spectrum was obtained via a silicon detector simulated in MCNPX. A window was designed to reduce the background signal caused by other nuclides. The sensitivity of the detector was also estimated, and its shielding designed for installation inside the reactor CT. Results and Discussion: The beta and gamma spectrum of the silicon detector showed a negligible gamma signal but it also contained an undesired peak at 0.22 MeV due to other nuclides, not the $^{16}N$ target nuclide. Window to remove the peak was derived as 0.4 mm for beryllium. The sensitivity of silicon beta detector with a beryllium window of 1.7 mm thickness was derived as $5.172{\times}10^{-6}{\mu}Ci{\cdot}cc^{-1}$. In addition, the specification of the shielding was evaluated through simulations, and the results showed that the integrity of the silicon detector can be maintained with lead shielding of 3 cm (<15 kg). This is a very small amount compared to the specifications of the lead shielding (600 kg) required for installation of $^{16}N$ gamma detector in inside reactor CT, it was determined that beta detector would have a distinct advantage in terms of miniaturization. Conclusion: The feasibility of the beta detector was evaluated for installation inside the reactor CT to detect small leaks below $0.5gpm{\cdot}hr^{-1}$. In future, the design will be optimized on specific data.

Protective effect of Tranilast on radiation-induced heart fibrosis in C57BL/6 mouse

  • Moon, Seongkwon
    • International Journal of Contents
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    • v.8 no.4
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    • pp.64-69
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    • 2012
  • The heart is a major dose-limiting organ for radiotherapy of cancer in the thoracic region. The purpose of this study was to examine the protective effect of tranilast on the radiation-induced heart fibrosis model using the C57BL/6 murine strain. A significant reduction in the expression of TGF-${\beta}1$, collagen type I and collagen type III was observed in the radiation plus tranilast group. The authors also suggest the use of tranilast in a clinical trial for the prevention of radiation-induced heart fibrosis.

Quality Control of Radiation Counting Systems and Measurement of Minimum Delectable Activity (방사선 계측기의 품질관리 및 최소검출방사능 측정)

  • 송병철;한성심;김영복;지광용;손세철
    • Proceedings of the Korean Radioactive Waste Society Conference
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    • 2004.06a
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    • pp.419-424
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    • 2004
  • Various radiation counters have been using to determine radioactivity of radwastes for disposal. A radiation counting system was set up using a radiation detector chosen in this study and its stability was investigated through the periodic determination of background and counting efficiencies in accordance with a quality control program to increase the confidence level. The average background level for the $\gamma$-spectrometer was 1.59 cps and the average counting level for the standard sample was 45248 Ops within $2{\sigma}$ confidence levels. The average alpha background level for the low background ${\alpha}{\beta}$ counting system was 0.31 cpm and the efficiency for alpha counting was 34.38%. The average beta background level for the ${\alpha}{\beta}$ counting system was 1,30 cpm and the efficiency for beta counting was 46.5%, The background level in the region of 3H and 14C for the liquid scintillation counting system was 2.52 and 3.31 cpm and the efficiency for alpha counting was 58.5 and 95.6%, respectively. The minimum detectable activity for the$\gamma$-spectrometer was found to be 3.2 Bq/$m\ell$ and 3.8 Bq/$m\ell$ for the liquid scintillation counter, and 20.5 and 23.0 Bq/$m\ell$, respectively for the $\alpha$ and $\beta$ counting system.

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Preparation of Radiation Detector and Radiation Dosimetry - TSEE Charactristics of LiF ( Mg , Cu , Na , Si ) Phosphor - (방사선 검출기의 제작과 방사선 선량측정 - LIF ( Mg , Cu , Na , Si ) 형광체의 TSEE 특성 -)

  • 도시홍
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.27 no.4
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    • pp.328-331
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    • 1991
  • LiF(Mg,Cu,Na,Si) 형광체의 ${\gamma}$선과 $\beta$선에 대한 TSEE 특성을 조사하였다. 상(60)Co ${\gamma}$선에 대한 감도는 약 450 counts/mR이었고, 여러 가지 $\beta$선에 대한 TSEE 에너지 의존성은 $\beta$입자의 평균에너지 0.02MeV에서 0.8MeV 사이에서 $\pm$10%이었다. 그리고 제작된 형광체 앞면에 7mg.cm 상(-2)의 인체 등가물질을 두 면 입사 $\beta$입자의 에너지에 무관하게 피부 흡수 선량을 측정할 수 있었다.

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Characterization of H460R, a Radioresistant Human Lung Cancer Cell Line, and Involvement of Syntrophin Beta 2 (SNTB2) in Radioresistance

  • Im, Chang-Nim;Kim, Byeong Mo;Moon, Eun-Yi;Hong, Da-Won;Park, Joung Whan;Hong, Sung Hee
    • Genomics & Informatics
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    • v.11 no.4
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    • pp.245-253
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    • 2013
  • A radioresistant cell line was established by fractionated ionizing radiation (IR) and assessed by a clonogenic assay, flow cytometry, and Western blot analysis, as well as zymography and a wound healing assay. Microarray was performed to profile global expression and to search for differentially expressed genes (DEGs) in response to IR. H460R cells demonstrated increased cell scattering and acidic vesicular organelles compared with parental cells. Concomitantly, H460R cells showed characteristics of increased migration and matrix metalloproteinase activity. In addition, H460R cells were resistant to IR, exhibiting reduced expression levels of ionizing responsive proteins (p-p53 and ${\gamma}$-H2AX); apoptosis-related molecules, such as cleaved poly(ADP ribose) polymerase; and endoplasmic reticulum stress-related molecules, such as glucose-regulated protein (GRP78) and C/EBP-homologous protein compared with parental cells, whereas the expression of anti-apoptotic X-linked inhibitor of apoptosis protein was increased. Among DEGs, syntrophin beta 2 (SNTB2) significantly increased in H460R cells in response to IR. Knockdown of SNTB2 by siRNA was more sensitive than the control after IR exposure in H460, H460R, and H1299 cells. Our study suggests that H460R cells have differential properties, including cell morphology, potential for metastasis, and resistance to IR, compared with parental cells. In addition, SNTB2 may play an important role in radioresistance. H460R cells could be helpful in in vitro systems for elucidating the molecular mechanisms of and discovering drugs to overcome radioresistance in lung cancer therapy.

Simulation of Beta Rays from Tritium with Cathode Rays (음극선을 이용한 삼중수소 베타선 모사)

  • Kim, KwangSin;Lee, Sook-Kyung;Son, Soon-Hwan;Lim, Hoon;Lee, Dong-Hwan
    • Journal of Radiation Industry
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    • v.2 no.3
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    • pp.141-148
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    • 2008
  • Beta rays emitted from tritium in titanium tritide film were simulated with cathode rays of a scanning electron microscope to investigate the effect of beta rays from tritium on semiconductor devices. The cathode ray currents, which vary with the change of applied energy and beam spot size, were measured with Faraday cup. The current from the semiconductor device irradiated with cathode rays at various conditions was measured. The cathode ray current increased with the increase of spot size to a maximum then decreased when the spot sized increased further. The magnitude of current produced in the semiconductor device is proportional to the magnitude of cathode ray current. The magnitude of cathode ray current at each energy level was matched to the intensity of beta ray to simulate the tritium beta ray spectrum. Then the semiconductor characteristics were analyzed with I-V curves.

The Anti-melanogenic Effect of Whitening Agent Containing Arbutin and ${\beta}-Glucosidase$ (알부틴과 베타-글루코시다제를 함유하는 미백 화장품의 항멜라닌 효과)

  • Lew Bark-Lin;Ryou Ji-Ho;Lee Mu-Hyoung
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.30 no.3 s.47
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    • pp.415-418
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    • 2004
  • Arbutin is a glycosylated hydroquinone found at high concentration in certain plants capable of surviving extreme and sustained dehydration. It has been reported to have an inhibitory effect of melanogenesis and to be hydrolyzed easily to yield glucose and hydroquinone by ${\beta}-glucosidase.$ While hydroquinone also has an anti-melanogenic effect, however, is carefully used as a topical whitening agent because of side effects. The present study was undertaken to examine the inhibitory effect of an whitening agent containing arbutin and ${\beta}-glucosidase$ on UV radiation induced pigmentation in human skin. Experimental subjects were UVB-irradiated on the back. UVB-irradiated areas were assigned to three groups: arbutin and ${\beta}-glucosidase$ treated group, vehicle control, and no-application control. Arbutin and ${\beta}-glucosidase$ treatment inhibited pigmentation by 50.17 percent, compared with the controls (N : 10: P<0.05). These results suggest that the whitening agent containing arbutin and ${\beta}-glucosidase$may be used as an agent to inhibit melanin formation induced by UV radiation.