• Pediatric Infection and Vaccine
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• v.6 no.2
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• pp.234-238
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• 1999

Purpose : This study was performed to evaluate the seropositivities and levels of Hepatitis A Virus(Hav) antibody in term pregnant women and their neonates, and the transplacental transfer rate of maternal Hav-specific IgG(Hav IgG) from tenn pregnant women to their neonates. Methods : During Jan. 1st, 1998 to May. 31 tho 1998, we collected the 42 pairs of sera from pregnant women and umbilical cord of their neonates in Korea University Ansan Hospital. The serum levels of Hav IgG were measured by the RIA method. Results : 1) The seropositivities of Hav IgG were 78.6% in mothers and 81.0% in neonates. There was no statistical difference of mean antibody(Ab) levels between mothers and neonates. There was significant correlation of Ab levels between maternal sera and neonatal umbilical cord sera(correlation coefficient r=0.9285, P<0.001). 2) There were no significant correlations between neonatal Hav IgG level and other factors such as maternal age, gestational age and initial body weight of neonates. Conclusion : Seropositivities of Hav IgG tenn-pregnant women was comparable to those of their neonates. Pregnant women and their neonates can be protected from Hav infection.

• The Korean Journal of Physiology
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• v.23 no.1
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• pp.13-21
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• 1989

The present study was designed to investigate i) the action of various nucleotides on membrane permeability of rat red blood cell and hepatocyte for $Na^{+}$ and $Rb^{+}$ ii) the characteristics of purinoceptors on these cell membranes. Blood from Sprague-Dawley rats was obtained by carotid arterial cannulation. Red blood cells were then washed 3 times with saline at $4{\circ}C$. Hepatic parenchymal cells were isolated from rat livers by using a modification of the Berry and Friend (1969) method. For the $Na^{+}$ influx studies, isolated RBC and hepatocyte were incubated in incubation medium containing $^{22}Na^{+}0.2\;{\mu}Ci/ml$ at $37^{\circ}C$. After various time intervals samples were removed from the incubation flask and washed out 3 times with ice-cold washing solutions. Cells were destroyed by adding Triton X-100 and TCA solution. After centrifugation, the supernatants were assayed for $^{22}Na^{+}$ by gamma counter. $^{86}Rb^{+}$ was used to simulate $K^{+}$ in these $K^{+}efflux$ studies. Isolated hepatocytes were incubated for 60 min in the loading solution containing $^{86}Rb^{+}\;10\;{\mu}Ci/ml$ at $37^{\circ}C$. After loading, the cells washed out 3 times by centrifugation with washing solution. The cells were incubated in buffer solution at $37^{\circ}C$. At intervals thereafter, samples were removed and centrifuged. The supernatants were analyzed for $^{86}Rb^{+}$ by liquid scintillation counter. The main results of the experiments were: 1) ATP and ATPP increased in both $^{22}Na^{+}$ influx and $^{86}Rb^{+}$ efflux in the red blood cell. Although ADP showed a tendency to increase in RBC membrane permeability for $^{22}Na^{+}$ and $^{86}Rb^{+}$, the changes were not significantly different from the control. 2) The Significant changes in $^{22}Na^{+}$ and $^{86}Rb^{+}$ flux by ATP were also demonstrated in hepatocyte. ATPP and ADP showed a tendency to increase in hepatocyte membrane permeability for both ions. 3) Other nucleoside triphosphates-ITP, GTP and CTP-did not change in membrane permeability for $^{22}Na^{+}$ and $^{86}Rb^{+}$ in RBC and hepatocyte. In conclusion, not only ATP but also ATPP activate purinoceptors and change in membrane permeability for $Na^{+}$ and $K^{+}$. In order to activate purinoceptors on the cell membrane, the nucleotides have to possess intact adenine moiety and three phosphates or more in its molecule.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.3 no.4
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• pp.301-307
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• 2005

The morphology of the high burnup $UO_2$ spent fuel, which was oxidized and annealed in a PIA (Post Irradiation Annealing) apparatus, has been observed. The high burnup fuel irradiated in Ulchin Unit 2, average rod burnup 57,000 MWd/tU, was transported to the KAERI's PIEF. The test specimen was used with about 200 mg of the spent $UO_2$ fuel fragment of the local burnup 65,000 MWd/tU. This specimen was annealed at $1400^{\circ}C$ for 4hrs after the oxidation for 3hrs to grain boundary using the PIA apparatus in a hot-cell. In order to oxidize the grain boundary, the oxidation temperature increased up to $500^{\circ}C$ and held for 3hrs in the mixed gas (60 ml He and 100 ml STD-air) atmosphere. The amount of 85Kr during the whole test process was measured to know the fission gas release behavior using the online system of a beta counter and a gamma counter. The detailed micro-structure was observed by a SEM to confirm the change of the fuel morphology after this test. As the annealing temperature increased, the fission products were observed to move to the grain surface and grain boundary of the $UO_2$ matrix. This specimen was re-structured through the reduction process, and the grain sizes were distributed from 5 to $10\;{\mu}m$.

• Journal of Periodontal and Implant Science
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• v.27 no.1
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• pp.129-150
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• 1997

The purpose of this study was to evaluate the effects of tetracycline(TC}, flurbiprofen, and PDGF-BB loaded biodegradable membranes on the cell-attachment, the activity of loaded PDGF-BB, in vivo release kinetics, and guided bone regenerative potentials. To evaluate the cell attachment to membranes, the number of gingival fibroblasts attached to each membrane(10% TC, 10% flurbiprofen, $200ng/cm^2$ PDGF-BB loaded membranes, drug-unloaded membrane) was counted by coulter counter and the morphologic pattern of attached cells was examined under SEM. To determine whether the activity of loaded PDGF-BB is sustained, the cellular growth and survival rate of gingival fibroblasts was used for both standard PDGF-BB and loaded PDGF-BB. For evaluation of in vivo release kinetics, drug-loaded membranes were implanted on the dorsal skin of the rats. On 1, 3, 7, 10, 14, 21, and 28 days after implantation, the amount of remaining drugs were measured by HPLC assay for TC and flurbiprofen, and by ${\gamma}-scintillation$ counter for $PDGF-BB^{1125}$. For evaluation of guided regenerative potential, the amount of new bone in the calvarial defect(5mm in diameter) of the rat was measured by histomorphometry 1 and 2 weeks after implantation of membranes. The number of cells attached to the PDGF-BB loaded membrane was largest as compared with the other mernbranes.(p< 0.05) The activity of loaded PDGF-BB was not significantly different from the activity of standard PDGF-BB.(p<0.05) After initial burst release of drug during the first 24 hours, drugs were gradually released for 4 weeks. Especially the release rate of PDGF-BB was nearly constant during 4 weeks. PDGF-BB loaded membranes(200, $400ng/cm^2$) were effective in guided bone regeneration as compared with drug-unloaded membrane. These results implicate that drug-loaded biodegradable membranes might be a useful for guided bone regeneration.

• Journal of the Korean Chemical Society
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• v.17 no.1
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• pp.20-24
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• 1973

The average fission neutron cross sections were determined for the following reactions, $^{93}Nb(n,\alpha)^{90}Y$, $^{90}Zr(n,p)^{90}Y$,$^{93}Nb(n,\alpha)^{90m}Y$and$^{90}Zr(n,p)^{90m}Y$. The cation exchange column was used for the quantitative separation of the product nuclides using $\alpha-$hydroxyisobutyric acid as the eluent. The absolute activites of $^{90m}Y$ and $^{90}Y$were determined by the gamma ray spectrometry and a calibrated $2\pi$gas flow counter, respectively. The cross sections of $^{93}Nb(n,\alpha)^{90}Y$, $^{90}Zr(n,p)^{90}Y$,$^{93}Nb(n,\alpha)^{90m}Y$and $^{90}Zr(n,p)^{90m}Y$ reactions were found to be$0.14\pm0.01mb$, $0.83\pm0.02mb$, $0.018\pm0.02mb$ and $0.33\pm0.02mb$, respectively. The possible use of $^{90m}Y$ instead of $^{90}Y$ was discussed as a better means for the determination of niobium.

• Progress in Medical Physics
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• v.25 no.1
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• pp.8-14
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• 2014

The amounts of radioactive wastes to be disposed in the medical institute have been increased due to development of radiation diagnosis and therapy rapidly. They are produced mostly by the very short lived radioisotopes such as $^{18}F$ used in PET/CT, $^{99m}Tc$, $^{123}I$, $^{125}I$ and $^{201}Tl$, etc. IAEA proposed a criteria for the clearance level of waste which depends on the individual ($10{\mu}Sv/y$) and collective dose (1 man-Sv/y), and concentration of each nuclide (IAEA Safety Series No 111-P-1.1, 1992 and IAEA RS-G-1.7, 2004). Radioactive wastes of $^{18}F$, $^{99m}Tc$, $^{123}I$, $^{125}I$ and $^{201}TI$ in the several types of container like Marinelli beaker, vial and plastic, were collected to measure the concentration of the waste of each nuclide in accordance with IAEA criteria. The measurement method and procedure of determining specific activity of the wastes using gamma emitters like MCA, gamma counter and beta emitters were developed. For the efficiency calibration of the detectors, CRM (certified reference material) which has the same dimension and shape was provided by Korea Research Institute of Standards and Science (KRISS). Correction factor of the radioactivity decay was calculated based on the measurement results, and the consideration of mutual relation with theoretical equation. The result of this study will be proposed as ISO standard.

• The Korean Journal of Nuclear Medicine
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• v.32 no.1
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• pp.89-98
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• 1998

The search for tumor-avid agents for use in nuclear medicine imaging is an ongoing field of importance. The purpose of this study was to determine the affinity for radio labeled vitamin $B_{12}$ by a wide histologic variety of tumor types in mice. Seventeen different types of tumor were grown subcutaneously in female Balb/C or Balb nu/nu(nude) mice. When the tumors reached about 1 cm in diameter, mice were injected intraperitoneally with $^{57}Co$-vitamin $B_{12}$. Twenty-four hours later, the mice were sacrificed. Organs and tissues were removed, weighed, and activity per mg determined by gamma counter. Values represented cpm/mg tissue that was normalized to 20 grams body weight for each mouse. A wide variety of tumor types showed significant uptake and concentration of $^{57}Co$-vitamin $B_{12}$, as evidenced by tumor:tissue activity ratios. For many tissues of great importance in terms of background(bone, muscle, blood), the tumor:tissue activity ratios of uptake were high. These data strongly suggest that further efforts to evaluate the utility of radio labeled adducts of vitamin $B_{12}$ for clinical use in oncologic imaging are warranted.

• The Korean Journal of Nuclear Medicine Technology
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• v.20 no.2
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• pp.69-74
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• 2016

Purpose Using a regression formula of the trendline near the coefficient of determination (R2) "1" by substituting the dependent variable of the standard curve to calculate the values of the independent variable. To determine the suitability of a regression equation by comparing the difference between the independent variables of the standard curve and the predicted independent variables. Materials and Methods Perkin Elmer Gamma-Counter machine was used for Standard curve of regression methods. TSH. TG-Ag (Thyroglobulin Antigen), Insulin that used materials and method test to compare the result from the Excel trendline of the regression formula. Results Each of the value of coefficient of determination ($R^2$) and Trendline $R^2=1$, Polynomial Trendline for TSH, $R^2=1$, Polynomial Trendline for TG-Ag, $R^2=0.9994$, Polynomial Trendline for Insulin. Conclusion We confirmed that IRMA immune method is found to the nearest trends elected a standard curve using polynomial trendline. The independent variables to predict the trend by using a polynomial trendline formula containing the error was a limitation.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.4
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• pp.1007-1013
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• 2004

The study was conducted to investigate per oral (PO) effects of Raspberry wine on testosterone levels in Sprague-Dawley rats. Raspberry wine of 13% alcohol concentration, was prepared from ripen fruits of Rubus coreanus fermented with Saccharomyces cervisiae. PO administration of Raspberry wine for 15 week (group A) produced dramatic increases of serum testosterone levels. Increase in the testosterone level was observed, using gamma counter with 1251 testosterone, starting from 1 week post administration. Maximum increase in testosterone level was observed at 5 week post administration, 7.486±6.482ng/mL, which was 14.6 times higher than normal and at 15 weeks post administration it was recorded as 1.84±3.516ng/mL. However, PO administration of Saccharomyces cervisiae broth (Group B) and 13% brewed alcohol (group C) for 15 weeks resulted slight increase in testosterone levels, indicating Raspberry wine as an effective phyto-testosogenic beverage of the future.

• Journal of the Korean Society of Radiology
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• v.3 no.1
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• pp.23-28
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• 2009

Medical radiation therapy using radioactive isotope I-131 is an extremely critical part of nuclear medicine. It is important to evaluate patients' radiation exposure dose for the safe handling of radiation in the medical area. Cautions related to patients' exposure to radiation are as follows. First, the dose should not exceed the level required for medical purpose. Second, unnecessary exposure should be avoided. Third, it should be considered carefully first whether the same medical purpose is attainable without the use of radiation. For these purposes, we need to evaluate patients' radiation exposure dose. Thus, in order to promote the safety of patients in medical wards, this study sampled air using an air sampler and measured the radioactivity of the sample using a gamma counter. According to the results of measuring I-131 in medical wards, the highest level, the average and the lowest level were $404.11Bq/m^3$, $228.27Bq/m^3$ and $126.17Bq/m^3$, respectively.