• 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.

• Korean Journal of Ecology and Environment
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• v.35 no.4 s.100
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• pp.326-330
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• 2002

A wetland soil was sterilised by two methods and changes in microbial enzyme activities were assessed. The short-term effects were determined by toluene addition, while the longer-term effects of elimination was monitored by ${\gamma}$-radiation. The changes in ${\beta}$- glucosidase, ${\beta}$-xylosidase, cellobiohydrolase, phosphatase, arylsulphatase, and N-acetylglucosaminidase activities were determined by using methylumbelliferyl model substrates and comparing with the activities of control samples. Toluene addition induced different responses of enzymes. For example, phosphatase activity increased by the treatment while ${\beta}$-glucosidase and arylsulphatase activities decreased. In contrast, ${\gamma}$-radiation decreased all enzyme activities compared to control by 40-80%. The overall results of the toluene and ${\gamma}$-radiation experiments indicate that the large amounts of enzymes are stabilised outside of living cells, at least in the short term, but that the persistence of enzymes is maintained by de-novo synthesis of microbes.

• The Korean Journal of Physiology and Pharmacology
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• v.17 no.4
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• pp.267-274
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• 2013

A beneficial radioprotective agent has been used to treat the radiation-induced lung injury. This study was performed to investigate whether curcumin, which is known to have anti-inflammatory and antioxidant properties, could ameliorate radiation-induced pulmonary inflammation and fibrosis in irradiated lungs. Rats were given daily doses of intragastric curcumin (200 mg/kg) prior to a single irradiation and for 8 weeks after radiation. Histopathologic findings demonstrated that macrophage accumulation, interstitial edema, alveolar septal thickness, perivascular fibrosis, and collapse in radiation-treated lungs were inhibited by curcumin administration. Radiation-induced transforming growth factor-${\beta}1$ (TGF-${\beta}1$), connective tissue growth factor (CTGF) expression, and collagen accumulation were also inhibited by curcumin. Moreover, western blot analysis revealed that curcumin lowered radiation-induced increases of tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), TNF receptor 1 (TNFR1), and cyclooxygenase-2 (COX-2). Curcumin also inhibited the nuclear translocation of nuclear factor-${\kappa}B$ (NF-${\kappa}B$) p65 in radiation-treated lungs. These results indicate that long-term curcumin administration may reduce lung inflammation and fibrosis caused by radiation treatment.

• Journal of Radiation Protection and Research
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• v.46 no.4
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• pp.194-203
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• 2021

Background: Surface soil radiation monitoring around nuclear facilities is important to classify and characterize the contaminated areas. A scanning and direct measurement technique can survey the sites rapidly before starting sampling analysis. Materials and Methods: Regarding this, we test and suggest a measurement technique for gross alpha/beta and ⁹⁰Sr activities in surface soil based on a mobile ZnS(Ag)/PVT (polyvinyltoluene) array and a handheld PVT rod, respectively. To detect ⁹⁰Sr selectively in soil mixed with naturally occurring radioactive materials, chosen energy channel counts from the multichannel analyzers were used instead of whole channel counts. Soil samples contaminated with exempt liquid ⁹⁰Sr with 1 Bq·g^-1, 3 Bq·g^-1, and 10 Bq·g^-1 were prepared and hardened by flocculation. Results and Discussion: The mobile ZnS(Ag)/PVT array could discriminate gross alpha, gross beta, and gamma radiation by the different pulse-shaped signal features of each sensor material. If the array is deployed on a vehicle, the scan minimum detectable concentration (MDC) range will be about 0.11-0.17 Bq·g^-1 at 18 km·h^-1 speed, highly sensitive to actual sites. The handheld PVT rod with 12 mm (Φ) × 20 mm (H) size can directly measure ⁹⁰Sr selectively if channels on which energies are from 1,470 and 2,279 keV are gated, minimizing crossdetection of other radionuclides. These methods were verified by measuring soil samples fabricated with homogeneous ⁹⁰Sr concentrations, showing static MDC of 2.16 Bq·g^-1 at a measurement time of 300 seconds. Conclusion: Based on the results, comprehensive procedures using these detectors are suggested to optimize soil sites survey.

• Radiation Oncology Journal
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• v.29 no.4
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• pp.219-227
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• 2011

Purpose: This study evaluated the treatment effectiveness and proper radiation dose of helical tomotherapy (HT) in spine oligometastases from gastrointestinal cancers. Materials and Methods: From 2006 to 2010, 20 gastrointestinal cancer patients were treated with HT for spine oligometastases (31 spine lesions). The gross tumor volume (GTV) was the tumor evident from magnetic resonance imaging images fused with simulation computed tomography images. Clinical target volume (CTV) encompassed involved vertebral bodies or dorsal elements. We assumed that the planning target volume was equal to the CTV. We assessed local control rate after HT for 31 spine metastases. Pain response was scored by using a numeric pain intensity scale (NPIS, from 0 to 10). Results: Spine metastatic lesions were treated with median dose of 40 Gy (range, 24 to 51 Gy) and median 5 Gy per fraction (range, 2.5 to 8 Gy) to GTV with median 8 fractions (range, 3 to 20 fraction). Median biologically equivalent dose (BED, ${\alpha}/{\beta}$ = 10 Gy) was 52 $Gy_{10}$ (range, 37.5 to 76.8 $Gy_{10}$) to GTV. Six month local control rate for spine metastasis was 90.3%. Overall infield failure rate was 15% and outfield failure rate was 75%. Most patients showed pain relief after HT (93.8%). Median local recurrence free survival was 3 months. BED over 57 $Gy_{10}$ and oligometastases were identified as prognostic factors associated with improved local progression free survival (p = 0.012, P = 0.041). Conclusion: HT was capable of delivering higher BED to metastatic lesions in close proximity of the spinal cord. Spine metastases from gastrointestinal tumors were sensitive to high dose radiation, and BED (${\alpha}/{\beta}$ = 10 Gy) higher than 57 $Gy_{10}$ could improve local control.

• Analytical Science and Technology
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• v.24 no.6
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• pp.414-420
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• 2011

In this study, radiation measurement system has been investigated to set up for the radioisotopes analysis in the radioactive waste samples after selecting the radiation counters of alpha beta and gamma nuclides. The counting efficiencies for alpha, beta and gamma measurement systems were calibrated. To obtain stability of the radiation detectors, quality control program has been established. Also, minimum detectable activities (MDAs) depending on the type of samples were calculated for increasing the confidence level for analytical result.

• 대한핵의학회:학술대회논문집
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• 1999.05a
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• pp.209-221
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• 1999

Coronary restenosis is still regarded as Achilles' Hill of interventional cardiology despite relentless efforts of many investigators. Recent experimental and clinical studies have suggested that both gamma and beta radiation can reduce restenosis after angioplasty. Currently, intracoronary brachytherapy for the prevention of restenosis has become a new evolving treatment modality in interventional cardiology. This report discusses a physical aspect of gamma and beta radiation, initial clinical results and delivery systems used in intracoronary brachytherapy. We shall take a brief overview of methods and their advantages in intra-coronary brachytherapy. Future work should provide further insight for the best way of treating restenosis.

• Carbon letters
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• v.15 no.4
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• pp.262-267
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• 2014

Pyrolized fuel oil (PFO) was reformed by novel electron beam (E-beam) radiation, and the elemental composition, chemical bonds, average molecular weight, solubility, softening point, yields, and density of the modified patches were characterized. These properties of modified pitch were dependent on the reforming method (heat or E-beam radiation treatment) and absorbed dose. Aromaticity ($F_a$), average molecular weight, solubility, softening point, and density increased in proportion to the absorbed dose of E-beam radiation, with the exception of the highest absorbed dose, due to modification by free radical polymerization and the powerful energy intensity of E-beam treatment. The H/C ratio and yield exhibited the opposite trend for the same reason. These results indicate that novel E-beam radiation reforming is suitable for the preparation of aromatic pitch with a high ${\beta}$-resin content.

• Nuclear Engineering and Technology
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• v.5 no.2
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• pp.83-86
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• 1973

The protective effects of acetylbenzoylaconine, 2-aminoethylisothiouronium bromide hydrobromide, $\beta$-mercaptoethylamine HCI, and L-thiazolidine-4-carboxylic acid were studied on the white male mice, aged 5-6 weeks. The toxicity test of acetylbenzoylaconine revealed that the LD$_{50}$ was 2.5 mg/kg of body weight. After the administration of test substances, mice were irradiated with whole body dose of 800 rad by the Co-60 source. Observing the number of surviving mice for 30 days, the survival coefficients for the test groups were calculated and with these the protective coefficients against radiation injury, PCR, were also calculated. The PCR values are 2.24, 2.95, 2.78, and 1.23 for acetylbenzoylaconine, 2-aminoethylisothiouronium bromide hydrobromiide, $\beta$-mercaptoethylamine HCI, and L-thiazolidine-4-carboxylic acid respectively. These values reveal that the acetylbenzoylaconine has protective potency against radiation injury on white male mice.

• Journal of Radiation Protection and Research
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• v.19 no.3
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• pp.179-188
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• 1994

Mice were whole body irradiated with dose of 2.88Gy and 7.2Gy(Co-60) in order to observe the morphological and functional changes in radio sensitive mouse ovary. Microtechnical sectionates of $7{\mu}m$ thickness from ovary were made for light microscopy and concentrations of progesterone, testosterone and estradiol in ovarian homogenates were analyzed by radioimmunoassay. Gamma radiation resulted in the increase of atretic ratio of preantral and antral follicles, the increase of progesterone concentration in ovarian homogenates, and the low level of testosterone and estradiol. It is suggested that radiation protect the activity of $3{\beta}-HSD$(hydroxysteroid dehydrogenase) and isomerase in the follicular theca cell followed by low level of testosterone and estradiol and thereafter follicular atresia proceed.