• The Korean Journal of Nuclear Medicine
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• v.30 no.4
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• pp.548-559
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• 1996

A series of performance measurements of positron emission tomography (PET) were performed following the recommendations of the Computer and Instrumentation Council of the Society of Nuclear Medicine and the National Electrical Manufacturers Association. We investigated the performance of the General Electric $Advance^{TM}$ PET. The measurements include the basic intrinsic tests of spatial resolution, scatter fraction, sensitivity, and count rate losses and randoms. They also include the tests of the accuracy of corrections: count rate linearity correction, uniformity correction, scatter correction and attenuation correction. GE $Advance^{TM}$ PET has bismuth germanate oxide crystals (4.0mm transaxial ${\times}$ 8.1mm axial ${\times}$ 30.0mm radial) in 18 rings, which form 35 imaging planes spaced by 4.25mm. The system has retractable tungsten septa 1mm thick and 12cm long. Transaxial resolution was 4.92mm FWHM in 2D and 5.14mm FWHM in 3D at the center. Average axial resolution in 2D decreased from 3.91mm FWHM at the center to 6.49mm FWHM at R=20cm. Average scatter fraction of direct and cross slices was 9.57%. Dead-time losses of 50% corresponded to a radioactivity concentration of $4.86{\mu}Ci/cc$ and a true count rate of 519 kcps in 2D. The accuracy of count rate linearity correction was 1.84% at the activity of $4.50{\mu}Ci/cc$. Non-uniformity was 2.06% in 2D and 2.93% in 3D. Remnant errors after scatter correction were 0.55% in 2D and 4.12% in 3D. The errors of attenuation correction were 6.21% (air), 0.20% (water), -6.32% (teflon) in 2D and 5.00% (air), 6.94% (water), 3.01% (teflon) in 3D. The results indicate the performance of GE $Advance^{TM}$ PET scanner to be well suited for clinical and research applications.

• The Korean Journal of Nuclear Medicine
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• v.37 no.3
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• pp.178-189
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• 2003

Purpose: Cellular uptakes of $^{99m}Tc-sestamibi(MIBI)\;and\;\;^{99m}Tc-tetrofosmin$ into cancer cell lines expressing multidrug resistance(MDR) were investigated and compared. The effects of verapamil and cyclosporin A, well-known multidrug resistant reversing agents, on cellular uptakes of both tracers were also compared. Materials and Methods: Doxorubicin-resistant HCT15/CL02 human colorectal cell and doxorubicin-resistant K562(Adr) and vincristine-resistant K562(Vcr) human leukemic cells were studied. RT-PCR analysis was used for the detection of mdr1 mRNA expression. MDR-reversal effects with verapamil and cyclosporine A were evaluated at different drug concentrations after incubation with MIBI and tetrofosmin for 1, 15, 30, 45 and 60 min, using single-cell suspensions at $1{\times}10^6cells/ml$ incubated at $37^{\circ}C$. Radioactivity in supernatants and pellets were measured with gamma well counter. Results: The cellular uptakes of MIBI and tetrofosmin in K562(Adr) and K562(Vcr) were lower than those of parental K562 cell. In HCT15/CL02 cells and K562(Adr) cells, there were no significant difference in cellular uptakes of both tracers, but cellular uptake of MIBI was higher than that of tetrofosmin in K562(Vcr) cells. Coincubation with verapamil resulted in a increase In cellular uptakes of MIBI and tetrofosmin. Verapamil increased cellular uptakes of MIBI and tetrofosmin by HCT15/CL02 cell by 11.9- and 6.8-fold, by K562(Adr) cell by 14.3- and 8-fold and by K562(Vcr) cell by 7- and 5.7-fold in maximum, respectively. Cyciosporin A increased cellular uptakes of MIBI and tetrofosmin by HCT15/CL02 cell by 10- and 2.4-fold, by K562(Adr) cell by 44- and 13-fold and by K562(Vcr) cell by 18.8- and 11.8-fold in maximum, respectively Conclusion: Taking together, MIBI and tetrofosmin are considered as suitable radiopharmaceuticals for defecting multidrug resistance. However, MIBI seems to be a better tracer than tetrofosmin for evaluating MDR reversal effect of the modulators. Since cellular uptakes of both tracers might differ in different cell types, further experiments regarding differences in cellular uptakes between cell types should be explored.

• Nuclear Medicine and Molecular Imaging
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• v.43 no.5
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• pp.478-486
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• 2009

Purpose: 5-iododeoxyuridine analogues have been exclusively developed for the potential antiviral and antitumor therapeutic agents. In this study, we synthesized carbocyclic radioiododeoxyuridineanalogue (ddIVDU) and carbocyclic intermediate as efficient carbocyclic radiopharmaceuticals. Materials and Methods: The synthesis is LAH reduction, hetero Diels-Alder reaction as key reactions including Pd(0)-catalyzed coupling reaction together with organotin. MCA-RH7777 (MCA) and MCA-tk (HSV1-tk positive) cells were treated with various concentration of carbocyclic ddIVDU, and GCV. Cytotoxicity was measured by the MTS methods. For in vitro uptake study, MCA and MCA-tk cells were incubated with 1uCi of [$^{125}I$]carbocyclic ddIVDU. Accumulated radioactivity was measured after various incubation times. Results: The synthesis of ddIVDU and precursor for radioiodination were achieved from cyclopentadiene in good overall yield, respectively. The radioiododemetallation for radiolabeling gave more than 80% yield with > 95% radiochemical purity. GCV was more toxic than carbocyclic ddIVDU in MCA-tk cells. Accumulation of [$^{125}I$]carbocyclic ddIVDU was higher in MCA-tk cells than MCA cells. Conclusion: Biological data reveal that ddIVDU is stable in vitro, less toxic than ganciclovir (GCV), and selective in HSV1-tk expressed cells. Thus, this new carbocyclic nucleoside, referred to in this paper as carbocyclic 2',3'-didehydro-2',3'-dideoxy-5- iodovinyluridine (carbocyclic ddIVDU), is a potential imaging probe for HSV1-tk.

• The Journal of Engineering Geology
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• v.26 no.2
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• pp.261-276
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• 2016

The occurrence of natural radioactive materials such as uranium and radon-222 in groundwater was examined with hydrogeochemistry and geology at ○○ village in the Yongin area. Two rounds of 19 groundwater and 5 surface water sampling were collected for analysis. The range of pH value in groundwaters was 5.81 to 7.79 and the geochemical types of the groundwater were mostly Ca(Na)-HCO₃ and Ca(Na)-NO₃(Cl)-HCO₃. Uranium and radon-222 concentrations in the groundwater ranged from 0.06 to 411 μg/L and from 5.56 to 903 Bq/L, respectively. Two deep groundwaters used as common potable well-water sources exceeded the maximum contaminant levels of the uranium and radon-222 proposed by the United States Environmental Protection Agency (US EPA). Three groundwater samples from residential areas contained unsuitable levels of uranium, and 12 groundwater samples were unsuitable due to radon-222 concentrations. Radioactive materials in the unsuitable groundwater are naturally occurring in a Jurassic amphibole- and biotite-bearing granitic gneiss. High uranium and radon-222 groundwater concentrations were only observed in two common wells; the others showed no relationship between bedrock geology and groundwater geochemical constituents. With such high concentrations of naturally occurring radioactive materials in groundwater, the affected areas may extend tens of meters for uranium and even farther for radon-222. Therefore, we suggest the radon-222 and the uranium did not originate from the same source. Based on the distribution of radon-222 in the study area, zones of higher radon-222 concentrations may be the result of diffusion through cracks, joint, or faults. Surface radioactivity and uranium concentrations in the groundwater show a positive relationship, and the impact areas may extend for ~200m beyond the well in the case of wells containing high concentrations of uranium. The highest uranium and thorium concentrations in rock samples were detected in thorite and monazite.

• Proceedings of The Korean Society of Health Promotion Conference
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• 2004.10a
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• pp.1-16
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• 2004

This paper considers the possibilities of health promotion from the following perspectives; (1) IUHPE, (2) socio-cultural similarities, (3) action research, and (4) learning from our past. 1. The IUHPE values decentralized activities through regions, and countries such as Japan, Korea, Hong Kong, Taiwan and China belong to NPWP region. Since IUHPE World Conference was held in Japan in 1995, Japan used to occupy more than 60% of NPWP membership. After 2001, membership is increasing rapidly in Chinese speaking sub-region. The transnational collaboration is still in its beginning phase. 2. Confucianism is one of key points. Confucian tradition should not be seen only as obstacles but as advantages to seek a form of health promotion more acceptable in East Asia. 3. Within the new public health framework, people are expected to create and live their health. However, especially in Japan, the tendency of 'lacking of face-to-face explicit interactions' is still common at health-promotion settings as well as academic settings. Therefore, the author tried participatory approaches such as asking WlFY (interactive questions designed for subjects to review their daily life and environment) and as introducing round table interactions. So far, majority of participants welcome new trials. 4. The following social phenomena are comparatively discussed after Japanese invasion and occupation of Korea ended in 1945; ·status of oriental medicine, ·separation of dispensary services, and ·health promotion specialist as a national license. In contrast to Japanese' tendency of maintaining the status quo and postponing of substantial social change, trend toward rapid and dynamic social changes are more commonly observed in Korea. Although all of above possibilities are still in their beginning stages, they are going to offer interesting directions waiting for further challenges and accompanying researches.

• Tuberculosis and Respiratory Diseases
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• v.43 no.2
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• pp.173-181
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• 1996

Background : Several studies have suggested that impaired mucociliary clearance plays a role in the pathophysiology of bronchial asthma. Cough productive of mucoid sputum is common, and mucous plugs in the airways are frequently observed. These clinical features are in keeping with the histologic lesions of asthma, which involve primarily the epithelial and mucous-producing structures of the conducting airways. Some studies have shown that the mucociliary clearance is impaired in adult asthma, but it has not been studied in childhood asthma. The objectives of this study were to examine whether the mucociliary clearance is impaired in childhood asthma and to estimate the degree of impairment in comparison with that of immotile cilia syndrome. Method : Thirteen children with mild stable asthma and eight patients with immotile cilia syndrome completed this study. Ten healthy children were recruited as a normal control group. The whole-lung mucociliary clearance was measured by the radioaerosol technique. Aerosols, tin colloid particles tagged with the radionuclide technetium-99m($^{99m}Tc$), were generated by means of nebulizer, and inhaled via a mouthpiece. The retention of radioactivity was measured at 30, 60, 90 and 120 minutes by gamma camera, and mucociliary clearance was calculated as percent retention at each time. Results: 1) In each subject, the percent retention decreased variably with the lapse of time. 2) The percent retention of radionuclide decreased at each time in order of normal control, bronchial asthma and immotile cilia syndrome and the percent retention of immotile cilia syndrome was significantly higher than that of normal control at each time(p<0.05). 3) At two hours, the percent retention of bronchial asthma($65.0{\pm}1.8$(SE)%) was significantly higher than that of the normal control($54.4{\pm}3.5%$, p<0.05), and significantly lower than that of immotile cilia syndrome($73.3{\pm}1.4%$, p<0.01). 4) When the percent retention was analyzed according to $PC_{20}$ in the children with bronchial asthma, they had no relationship with each other. Conclusion: Mucociliary clearance in the children with bronchial asthma was significantly lower than normal control. This finding indicates that impaired mucociliary clearance operates in childhood asthma as well, and suggests that it may be one contributing factor in the pathogenesis of asthma. The degree of impairment, however, was not so severe as immotile cilia syndrome.

• Proceedings of the Ginseng society Conference
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• 1988.08a
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• pp.47-54
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• 1988

Cholesterol a component of all eucaryotic plasma membranes. is essential for the growth and viability of cells in higher organisms. However. too much cholesterol can be lethal because of atherosclerosis resulting from the deposition of cholesterol ester plaques. It was attempted in this study to understand the preventive effect of ginseng saponin. one of the major components of the roots of Panax ginseng C.A. Meyer. against hypercholesterolemia induced by high cholesterol diet. $^{125}I-LDL$ was injected intravenously to rabbits and rats. which were fed a high cholesterol diet with and/or without ginseng saponin for 12 days. The disappearance of the radioactivity occurred faster in the test group than the control. The effect of saponin fraction from Panax ginseng C.A. Meyer and the purified ginsenosilks. $Rb_1,\;Rb_2,\;Re\;and\;Rg_1,$ on LDL receptor biosynthesis in high cholesterol fed rat has been investigated. Analysis of LDL receptors from various organs such as liver. kidney. adrenal cortex and testis showed that the population of LDL receptors of test group significantly higher than that of the control. It was also found that liver homogenate containing ginsenosides $(10^{-3}-10^{-4}\%)$ stimulated the biosynthesis of bile acid form cholesterol. From the above results. it seemed that ginsenosides lower the cholesterol level by stimulating cholesterol metabolism. which result in the suppression of the inhibitory action of cholesterol on LDL receptor biosynthesis.

• The Korean Journal of Nuclear Medicine
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• v.38 no.6
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• pp.532-539
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• 2004

Purpose: There has been a renewal of interest in Macrophage migration inhibitory factor (MIF), especially correlation in pathogenesis of sepsis by many infectious diseases and in regulation of host inflammatory and immune response. We developed immunoradiometric assay (IRMA) to determine serum human MIF concentration. Materials and Methods: The IRMA system utilizes solid phase bound monoclonal anti-recombinant human MIF (rhMIF) antibody as a capture antibody, biotinylated polyclonal anti-rhMIF antibody as a detector antibody. We applied with rhMIF that concentration of standard solutions increased from 0 ng/ml to 100 ng/ml. We used $^{125}I$-streptavidin (SA) as radiotracer to determination of rhMIF concentration. Streptavidin was labeled with $^{125}I$ by Chloramine-T method and $^{125}I$-SA was purified by ultracentrifugation. $^{125}I$-SA stability was evaluated by ITLC analysis at $4^{\circ}C$ and room temperatures until 60days. To validate IRMA system for MIF, we experimented intra-assay and inter-assay coefficients of variation, recovery test and dilution test. Results: Radiolabeling yield of $^{125}I$-SA was 87% and purified $^{125}I$-SA retained above 99% radiochemical purity. $^{125}I$-SA showed above 93% stability in $4^{\circ}C$ until 60days that it is good for immunoradiometric assay as radiotracer. Plotted standard dose response curve showed that increased concentration of rhMIF linearly correlated (R2=0.99) with bound radioactivity of $^{125}I$-SA. The highest intra- and inter-assay coefficients of variation were 5.5% and 7.6%, respectively. The average of recovery of MIF in samples was 102%. In dilution test, linear response curves were obtained (R2=0.97). Conclusion: Radioimmunoassay using $^{125}I$-SA as radiotracer thought to be useful for the determination of serum MIF concentration, and further, its data will be used to evaluate the correlation between clinical significance and serum MIF concentration in patients with various inflammatory diseases.

• The Journal of Engineering Geology
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• v.25 no.4
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• pp.557-576
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• 2015

Groundwaters in granite, gneiss, and two-mica granite formations, including faults, in the Hoengseong area are examined to determine the relationship between their uranium and radon-222 contents and rock types. The chemical compositions of 38 groundwater samples and four surface water samples collected in the study area were analyzed. Sixteen of the samples showing high uranium and radon-222 contents were repeatedly analyzed. Surface radioactivities were measured at 30 points. The uranium and radon-222 concentrations in the groundwater samples were in the ranges of 0.02-49.3 μg/L and 20-906 Bq/L, respectively. Four samples for uranium and 35 samples for radon had concentrations exceeding the alternative maximum contaminant level of the US EPA. The chemical compositions of groundwaters indicated Ca(Na)-HCO₃ and Ca(Na)-NO₃(HCO₃+Cl) types. The pH values ranged from 5.71 to 8.66. High uranium and radon-222 contents in the groundwaters occurred mainly at the boundary between granite and gneiss, and in the granite area. The occurrence of uranium did not show any distinct relationship to that of radon-222. The radon-222, an inert gas, appeared to be dissolved in the groundwater of the aquifer after wide diffusion along rock fractures, having been derived from the decay of uranium in underground rocks. The results in this study indicate that groundwater of neutral or weakly alkaline pH, under oxidizing conditions and with a high bicarbonate content is favorable for the dissolution of uranium and uranium complexes such as uranyl or uranyl-carbonate.

• Journal of radiological science and technology
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• v.29 no.2
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• pp.75-81
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• 2006

In the past, most patient of breast cancer suffered side effects due to the useless removement of Axillary Lymph Node, but there is no need to remove it because of the result in this study. The purpose of this study is to save surgery time and side effects after surgical operation for patients with breast cancer by making decisions of operation range for metastasis in first Stenosis Lymph Node using the $^{99m}Tc-Tincolloid$ Scintigraphy and the Micro Probe for radioisotope. As a result of this study, 15 among 20 patients became objects of this study could reduced side effects for operation because there were no axillary lymph node operations. However there is no standard for method of this treatment. It should be standardize where inject point is, how much $^{99m}Tc-Tincolloid$ should be injected(radioactivity value), and the need of massage and Lymph Scintigraphy. Nevertheless I think that this result of study is useful to reduce suffering and side effects from breast cancer and also we should try to do that continuously. The objects for this study were 20 patients diagnosed as breast cancer by Ultrasonography, Mammography & Biopsy. The average of patient age was 45.4 years and its range was between 31 and 71 years. In case of clinical period there were 9 patients of Period I and II patients of Period III. The equipment for this study were $^{99m}Tc-Tincolloid$ describing the Stenosis Lymph Node as a tracer, Micro Probe : Neoprobe 2000(the rest is Gamma Probe) tracing the location, and MS-II Gamma Camera : SIEMENS(the rest is MS-II Gamma Camera) describing the images. There were 3 methods for this study, after selecting one of those methods all 20 patients were performed Stenosis Lymph Node diagnosis & Gamma Probe in operation room. The result was that I imaged all the 20 patients, and seek the Stenosis Lymph Node by using Gamma Probe. Metastasis in Stenosis Lymph Node was 5 and Metastasis in Axillary Lymph Node was 3 between Metastasis in Stenosis Lymph Node cases. Finally 15 patients were also proved that Axillary Lymph Node was Positive and that means there was no Metastasis in Axillary Lymph Node.