• Title/Summary/Keyword: Activity/Attenuation

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Quality Management of Radionuclide Activity Meter using Ge-68/Ga-68 Rod Sources (Ge-68/Ga-68 Rod Sources을 이용한 방사능측정기의 정도관리)

  • Jung, Seung Hwan;Jin, Gye Hwan
    • Journal of the Korean Society of Radiology
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    • v.12 no.5
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    • pp.575-582
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    • 2018
  • This article compared accuracy of 5 types of radionuclide activity meters that are being used in medical institutions and proposed the correction factor for each radionuclide activity meters type, using Ge-68/Ga-68 radiation sources for scanner setting, regular scanner correction, attenuation correction, and normalization. The calibration constant between baseline values and measured values by CRC-15R, CRC-15 PET, CRC-712M, CRC-15 Beta, and CRC-25PET was 0.99999(P<0.0001), which showed very high linearity. In the accuracy test, CRC-15R, CRC-15 PET, CRC-712M, CRC-15 Beta, and CRC-25PET model showed -3.232%, -1.342%, -2.815%, -2.913%, and -3.089% respectively.

A Study on the Mechanism of Immunomodulating Effects of Moxifloxacin in Oleic Acid-Induced Acute Lung Injury

  • Lee, Young-Man
    • Tuberculosis and Respiratory Diseases
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    • v.71 no.2
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    • pp.97-105
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    • 2011
  • Background: It was hypothesized that the immunomodulating effects of moxifloxacin contribute to ameliorate oleic acid (OA)-induced acute lung injury (ALI) by suppression of cytosolic phospholipase A2 (cPLA2). This was based on observations from experiments on rats associated with neutrophilic respiratory burst, cPLA2 activity, and expressions of cPLA2, $TNF{\alpha}$, and COX-II in the lung. Methods: ALI was induced by intravenous injection of OA in male Sprague-Dawley rats. Five hours after OA injection, protein content in bronchoalveolar lavage (BAL), lung myeloperoxidase (MPO) activity, and numbers of BAL neutrophils were measured. As an index of oxidative stress-induced lung injury, the content of malondialdehyde (MDA) in lung tissues was also determined. Lung histology, immunohistochemistry and determination of activity of cPLA2 in lung tissues were carried out. In addition, Western blotting of $TNF{\alpha}$ and COX-II in lung tissues was performed. Results: The accumulation of neutrophils in the lungs was observed after OA injection. BAL protein was increased along with neutrophilic infiltration and migration by OA. Moxifloxacin decreased all of these parameters of ALI and ameliorated ALI histologically. The increased malondialdehyde (MDA) in the lung by OA was also decreased by moxifloxacin. Moxifloxacin not only suppressed cPLA2 expression in the lungs and neutrophils but also decreased cPLA2 activity in lung tissues of rats given OA. The enhanced expressions of $TNF{\alpha}$ and COX-2 in the lung tissues of rats given OA were also suppressed by moxifloxacin. Conclusion: Moxifloxacin inhibited cPLA2 and down-regulated $TNF{\alpha}$ and COX-2 in the lungs of rats given OA, which resulted in the attenuation of inflammatory lung injury.

Suppression of β-Secretase (BACE1) Activity and β-Amyloid Protein-Induced Neurotoxicity by Solvent Fractions from Petasites japonicus Leaves

  • Hong, Seung-Young;Park, In-Shik;Jun, Mi-Ra
    • Preventive Nutrition and Food Science
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    • v.16 no.1
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    • pp.18-23
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    • 2011
  • Alzheimer's disease (AD) is a neurodegenerative disorder characterized by neuronal loss and extracellular senile plaques containing $\beta$-amyloid peptide (A$\beta$). The deposition of the A$\beta$ peptide following proteolytic processing of amyloid precursor protein (APP) by $\beta$-secretase (BACE1) and $\gamma$-secretase is a critical feature in the progression of AD. Among the plant extracts tested, the ethanol extract of Petasites japonicus leaves showed novel protective effect on B103 neuroblastoma cells against neurotoxicity induced by A$\beta$, as well as a strong suppressive effect on BACE1 activity. Ethanol extracts of P. japonicus leaves were sequentially extracted with methylene chloride, ethyl acetate and butanol and evaluated for potential to inhibit BACE1, as well as to suppress A$\beta$-induced neurotoxicity. Exposure to A$\beta$ significantly reduced cell viability and increased apoptotic cell death. However, pretreatment with ethyl acetate fraction of P. japonicus leaves prior to A$\beta$ (50 ${\mu}M$) significantly increased cell viability (p<0.01). In parallel, cell apoptosis triggered by A$\beta$ was also dramatically inhibited by ethyl acetate fraction of P. japonicus leaves. Moreover, the ethyl acetate fraction suppressed caspase-3 activity to the basal level at 30 ppm. Taken together, these results demonstrated that P. japonicus leaves appear to be a useful source for the inhibition and/or prevention of AD by suppression of BACE1 activity and attenuation of A$\beta$ induced neurocytotoxicity.

Anti-oxidative and anti-inflammatory effects of Odukhwan and Sasinhwan in RAW264.7 cells (오덕환(五德丸)과 사신환(四神丸)의 항산화 및 항염증 효과)

  • Kim, Tae-Hoon;Cho, Hyun-Jin;Park, Sun-Dong
    • Herbal Formula Science
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    • v.20 no.2
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    • pp.65-82
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    • 2012
  • Objectives : The aim of this study was verification of the anti-oxidative and anti-inflammatory effects of Odukhwan(ODH) and Sasinhwan(SSH) in mouse macrophage, RAW264.7 cells. Methods : To investigate the anti-oxidative effect and scavenging activities of DPPH radical, superoxide anions, nitric oxide and peroxynitrite were measured. Cytotoxic activity of extract of ODH and SSH on RAW264.7 cells was measured using MTS assay. To proof the reductive activity of intracellular oxidation, DCFH-DA assay was performed. The nitric oxide(NO) production was measured and pro-inflammatory cytokines and $PGE_2$ were measured by ELISA kit. The levels of inducible nitric oxide synthase(iNOS), cyclooxygenase-2(COX-2) and nuclear NF-${\kappa}B$ p65 expression were detected by western blot. Results : After those analyses, we bring to a conclusion as follows. Both herbal formulations scavenged DPPH radical and nitric oxide. But ODH had no scavenging activity of superoxide anions and SSH had low scavenging activity in peroxynitrite. And the results indicated that ODH and SSH inhibited the LPS-induced NO, $PGE_2$ production and iNOS, COX-2 expression accompanied by an attenuation of IL-$1{\beta}$ and IL-6 production in RAW264.7 cells. They also have suppression effects of LPS-induced NF-${\kappa}B$ activation. Conclusions : ODH and SSH have anti-oxidative and anti-inflammatory effects and they may be a part of database for development of new anti-oxidative and anti-inflammatory drugs.

Iodine Quantification on Spectral Detector-Based Dual-Energy CT Enterography: Correlation with Crohn's Disease Activity Index and External Validation

  • Kim, Yeon Soo;Kim, Se Hyung;Ryu, Hwa Sung;Han, Joon Koo
    • Korean Journal of Radiology
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    • v.19 no.6
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    • pp.1077-1088
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    • 2018
  • Objective: To correlate CT parameters on detector-based dual-energy CT enterography (DECTE) with Crohn's disease activity index (CDAI) and externally validate quantitative CT parameters. Materials and Methods: Thirty-nine patients with CD were retrospectively enrolled. Two radiologists reviewed DECTE images by consensus for qualitative and quantitative CT features. CT attenuation and iodine concentration for the diseased bowel were also measured. Univariate statistical tests were used to evaluate whether there was a significant difference in CTE features between remission and active groups, on the basis of the CDAI score. Pearson's correlation test and multiple linear regression analyses were used to assess the correlation between quantitative CT parameters and CDAI. For external validation, an additional 33 consecutive patients were recruited. The correlation and concordance rate were calculated between real and estimated CDAI. Results: There were significant differences between remission and active groups in the bowel enhancement pattern, subjective degree of enhancement, mesenteric fat infiltration, comb sign, and obstruction (p < 0.05). Significant correlations were found between CDAI and quantitative CT parameters, including number of lesions (correlation coefficient, r = 0.573), bowel wall thickness (r = 0.477), iodine concentration (r = 0.744), and relative degree of enhancement (r = 0.541; p < 0.05). Iodine concentration remained the sole independent variable associated with CDAI in multivariate analysis (p = 0.001). The linear regression equation for CDAI (y) and iodine concentration (x) was y = 53.549x + 55.111. For validation patients, a significant correlation (r = 0.925; p < 0.001) and high concordance rate (87.9%, 29/33) were observed between real and estimated CDAIs. Conclusion: Iodine concentration, measured on detector-based DECTE, represents a convenient and reproducible biomarker to monitor disease activity in CD.

TPH Removal of the Biodegradation Process Using 4 Indigenous Microorganisms for the Diesel Contaminated Soil in a Military Camp (디젤로 오염된 군부대 토양에 대하여 토착미생물 4종을 이용한 생분해법의 TPH 제거 효율 규명)

  • Park, Min-Ho;Lee, Min-Hee
    • Journal of Soil and Groundwater Environment
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    • v.17 no.3
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    • pp.49-58
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    • 2012
  • Batch experiments using indigenous and commercialized adventive microorganisms were performed to investigate the feasibility of the biodegradation process for the diesel contaminated soil, which was taken in US Military Camp 'Hialeah', Korea. TPH concentration of the soil was determined as 3,819 mg/kg. Four indigenous microorganisms having high TPH degradation activity were isolated from the soil and by 16S rRNA gene sequence analysis, they were identified as Arthrobacter sp., Burkholderia sp., Cupriavidus sp. and Bacillus sp.. Two kinds of commercialized solutions cultured with adventive microorganisms were also used for the experiments. Various biodegradation conditions such as the amount of microorganism, water content and the temperature were applied to decide the optimal bioavailability condition in the experiments. In the case of soils without additional microorganisms (on the natural attenuation condition), 35% of initial TPH was removed from the soil by inhabitant microorganisms in soil for 30 days. When the commercialized microorganism cultured solutions were added into the soil, their average TPH removal efficiencies were 64%, and 54%, respectively, which were higher than that without additional microorganisms. When indigenous microorganisms isolated from the contaminated soil were added into the soil, TPH removal efficiency increased up to 95% (for Bacillus sp.). According to the calculation of the average biodegradation rates for Bacillus sp., the remediation goal (87% of the removal efficiency: 500 mg/kg) for the soil would reach within 24 days. Results suggested that TPH removal efficiency of biodegradation by injecting indigenous microorganisms is better than those by injecting commercialized adventive microorganisms and only by using the natural attenuation.

Effect of silver nanoparticles on the performance of riverbank filtration: Column study (강변여과에서의 은나노입자의 영향 : 실험실규모 컬럼 실험)

  • Lee, Donghyun;No, Jin-Hyeong;Kim, Hyun-Chul;Choi, Jae-Won;Choi, Il-Hwan;Maeng, Sungkyu
    • Journal of Korean Society of Water and Wastewater
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    • v.29 no.1
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    • pp.77-88
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    • 2015
  • Soil column experiments were evaluated effects of silver nanoparticles (i.e., 0, 2.5, 5, and 10 mg/L) on the microbial viability which is strongly associated with the degradation of organic matter, pharmaceutically active compounds(PhACs) and biological oxidation of nitrogenous compounds during river bank filtration. The addition of silver nanoparticles resulted in almost no change in the aqueous matrix. However, the intact cell concentration decreased with addition of silver nanoparticles from 2.5 to 10 mg/L, which accounted for 76% to 82% reduction compared to that of control (silver nanoparticles free surface water). The decrease in adenosine triphosphate was more pronounced; thus, the number and active cells in aqueous phase were concurrently decreased with added silver nanoparticles. Based on the florescence excitation-emission matrix and liquid chromatograph - organic carbon detection analyses, it shows that the removal of protein-like substances was relatively higher than that of humic-like substances, and polysaccharide was substantially reduced. But the extent of those substances removed during soil passage was decreased with the increasing concentration of silver nanoparticles. The attenuation of ionic PhACs ranged from 55% to 80%, depending on the concentration of silver nanoparticles. The attenuation of neutral PhACs ranged between 72% and 77%, which was relatively lower than that observed for the ionic PhACs. The microbial viability was affected by silver nanoparticles, which also resulted in inhibition of nitrifiers.

Study on the Inhibitory Effect of Anti-Alzheimer in CT105-induced Neuro 2A Cell Lines by Gamiyaungshinhwan Water Extract (가미녕신환(加味寧神丸)이 CT105로 유도된 Neuro2A 세포주에서의 항치매 효과(效果))

  • Bang, Jae-Sun;Yoon, Hyun-Duk;Shin, Oh-Chul;Shin, Yoo-Jung;Park, Chi-Sang
    • The Journal of Internal Korean Medicine
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    • v.27 no.3
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    • pp.603-616
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    • 2006
  • The water extract of Gamiyaengshinhwan (GYH), has been used in vitro tests for its beneficial effects on neuronal survival and neuroprotective functions, particularly in connection with CT105-related dementias and Alzheimer's disease(AD). CT105 derived from proteolytic processing of the $\beta$-amyloid precursor protein (APP), including the amyloid-$\beta$ peptide ($A{\beta}$), plays a critical role in the pathogenesis of Alzheimer's dementia. We determined that transfected overexpressing APP695 and $A{\beta}$ CT105 have a profound attenuation in the Increase in CT105 expressing neuro2A cells from GYH. Experimental evidence indicates that GYH protects against neuronal damage from cells, but its cellular and molecular mechanisms remain unknown. Using a neuroblastoma cell line stably expressing CT105-associated neuronal degeneration, we demonstrated that GYH inhibits formation of amyloid-$\beta$ fragment ($A{\beta}$ CT105). which are the characteristic, and possibly causative, features of AD. The decreased CT105 $A{\beta}$ in the presence of GYH was observed in the conditioned medium of this CT105-secreting cell line under in vitro. In the cells, GYH significantly attenuated mitochondrion-initiated apoptosis and decreased the activity of Bax, a key enzyme in the apoptosis cell-signaling cascade. These results suggest that neuronal damage in AD might be due to two factors: a direct CT05 toxicity and the apoptosis initiated by the mitochondria. Multiple cellular and molecular neuroprotective mechanisms, including attenuation of apoptosis and direct inhibition of CT105 aggregation, underlie the neuroprotective effects of GYH.

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The protective effects of trace elements against side effects induced by ionizing radiation

  • Hosseinimehr, Seyed Jalal
    • Radiation Oncology Journal
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    • v.33 no.2
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    • pp.66-74
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    • 2015
  • Trace elements play crucial role in the maintenance of genome stability in the cells. Many endogenous defense enzymes are containing trace elements such as superoxide dismutase and metalloproteins. These enzymes are contributing in the detoxification of reactive oxidative species (ROS) induced by ionizing radiation in the cells. Zinc, copper, manganese, and selenium are main trace elements that have protective roles against radiation-induced DNA damages. Trace elements in the free salt forms have protective effect against cell toxicity induced by oxidative stress, metal-complex are more active in the attenuation of ROS particularly through superoxide dismutase mimetic activity. Manganese-complexes in protection of normal cell against radiation without any protective effect on cancer cells are more interesting compounds in this topic. The aim of this paper to review the role of trace elements in protection cells against genotoxicity and side effects induced by ionizing radiation.

Development of a Kinematic Wave Model to Route Overland Flow in Vegetated Area (II) -Runoff Plot Experiments and Model Application- (초지의 지표면 흐름을 추적하기 위한 Kinematic Wave Model의 개발(II) - 포장실험과 모형의 응용 -)

  • ;W.L.Magette
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.35 no.3
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    • pp.74-80
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    • 1993
  • Runoff simulation tests to investigate the flow mechanics of nonsuomerged overland flow in a natural grass intervening land system were condueted and a modified kinematic wave overland runoff model developed by Choi et al. (1993) was verified. Nonhomogeneity and heterogeneity of the soil, slope, local topography, infiltration, grass density, and the density and activity of the soil microhes and wild animals were the major factors affecting the flow. Streamlines were disturbed by grass stems and small concentrated flows due to the disturbed streamlines and local topography were observed a lot. Relatively larger concentrated flows were observed where bundles of grass were dominant than where individual grasses were growing. Predicted hydrographs were agreed verv well with measured hydrographs. Since the modified model considers grass density in computing flow depth and hydraulic radius, it can be better than existing kinematic wave model if it were used to route nonpoint source pollutant attenuation processes in many grass intervening land systems.

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