• 대한수의학회지
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• 제55권1호
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• pp.57-60
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• 2015

To investigate kinetics of free $^{177}Lu$ and $^{177}Lu$-labeled thermally cross-linked superparamagnetic iron oxide nanoparticles (TCL-SPION), suspensions were intravenously injected into the tail vein of mice at a dose of $5{\mu}Ci$/mouse or 15 mg/kg body weight, respectively. Free $^{177}Lu$ radioactivity levels were highest in kidney followed by liver and lung 1 day post-injection. $^{177}Lu$-labeled TCL-SPION radioactivity in liver and spleen was significantly higher compared to that of other organs throughout the experimental period (p < 0.05). Radioactivity in blood, brain, and epididymis rapidly declined until 28 days. Based on these results, TCL-SPION could be a safe carrier of therapeutics.

• Journal of Ginseng Research
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• 제9권2호
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• pp.213-220
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• 1985

It was attempted to observe the effects of ginseng saponin, one of the major components of the roots of Panax ginseng, on androgen biosynthesis from cholesterol in vitro as well as in vivo in rat testis. Ginseng saponin was administered by stomach tubing prior to intraperitoneal injection of cholesterol containing (4-14C)-cholesteroll into adult male rats and the liver, testis and blood serum were analyzed. The first high radioactivity of the liver and blood serum of test animal was observed at 6 hours after radioactive cholesterol injection, while that of control appeared at 12 hours after the injection. In the case of testis, the first high radioactivity of test group appeared between 4 and 6 hours after the radioactive cholesterol injection, while that of control appeared at 10-14 hours. Analysis of radioactivity distribution of cholesterol, androstenedione and testosterone in the testis of rats fed with/without ginseng saponin piror to (4-14C)-cholesterol injection showed that the saponin stmulated the synthesis of androgens from cholesterol. This was confirmed again by in vitro experiment using testis homogenate as an enzyme source. From the above experimental results, it was suggested that the ginseng saponin stimulates both cholesterol transport and the biosynthesis of androgens from cholesterol in rat testis.

• Journal of Ginseng Research
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• 제15권2호
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• pp.112-116
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• 1991

The metabolic fate of ginsenosides including gastrointestinat absorption, organ distribution, excretion and metabolism in liver was investigated by tracer studies using the radio-labeled ginsenosides. 3H-ginsenosides were shown to be absorbed from the mouse digestive tract and then to be excreted rapidly into urine and/or bile. Bile juice was concluded to play a significant role in absorption of ginsenosides. The total concentration of radioactivity persisted in tissues 24 hrs after oral administration was less than 1.3% of the administered dose and Rbl showed the highest value. The concentrations of radioactivity were relatively high in the liver and kidney. After administration of Rbl radioactivity was detected in the brain. After oral administration of 8H-ginsenosides, major component excreted into urine was found to be the intact ginsenosides and decomposed and/or metabolized products were found in GIT in the case of Rbl. 3H-ginsenoside Rbl was shown to be metabolized in the liver and the metabolite was suggested to be an acylated compound of Rbl by a certain organic acid.

• 수산경영론집
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• 제52권4호
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• pp.29-43
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• 2021

This study investigated whether there is a correlation between the occurrence of hazardous substances such as vibrio, norovirus, radioactivity, shellfish posion, hepatitis A, etc. and media reports, and whether the occurrence of hazardous substances and media reports affect the production, distribution and consumption of aquatic products. The main research results are as follows. First, it can be seen that there is a difference in the relationship between the occurrence of hazardous substances and media reports according to hazardous substances. Second, it suggests seen that the occurrence of hazardous substances and media reports can have a negative effect on the production and the prices of aquatic products. Third, it was found that the occurrence and reporting of hazardous substances had different effects on the distribution margin of aquatic products due to the complexity and rigidity of the distribution structure. Fourth, consumers feel a threat to aquatic products safety and significantly reduce consumption when hazardous substances occur. There is a possibility that concerns about one item may lead to a decrease in consumption of domestic and imported aquatic products that are not related at all to the occurrence of hazardous substances. In conclusion, aquatic products are exposed to various hazardous substances such as vibrio, norovirus, radioactivity, shellfish posion, and hepatitis A. It was found that the occurrence of hazardous substances and its media reports could cause damage to the fishery sector.

• Journal of Radiation Protection and Research
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• 제43권3호
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• pp.85-96
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• 2018

Background: A variety of inorganic scintillators have been developed and improved for use in radiation detection and measurement, and in situ gamma-ray spectrometry in the environment remains an important area in nuclear safety. In order to verify the feasibility of promising scintillators in an actual environment, a performance test is necessary to identify gamma-ray peaks and calculate the radioactivity from their net count rates in peaks. Materials and Methods: Among commercially available scintillators, $LaBr_3(Ce)$ scintillators have so far shown the highest energy resolution when detecting and identifying gamma-rays. However, the intrinsic background of this scintillator type affects efficient application to the environment with a relatively low count rate. An algorithm to subtract the intrinsic background was consequently developed, and the in situ calibration factor at 1 m above ground level was calculated from Monte Carlo simulation in order to determine the radioactivity from the measured net count rate. Results and Discussion: The radioactivity of six natural radionuclides in the environment was evaluated from in situ gamma-ray spectrometry using an $LaBr_3(Ce)$ detector. The results were then compared with those of a portable high purity Ge (HPGe) detector with in situ object counting system (ISOCS) software at the same sites. In addition, the radioactive cesium in the ground of Jeju Island, South Korea, was determined with the same assumption of the source distribution between measurements using two detectors. Conclusion: Good agreement between both detectors was achieved in the in situ gamma-ray spectrometry of natural as well as artificial radionuclides in the ground. This means that an $LaBr_3(Ce)$ detector can produce reliable and stable results of radioactivity in the ground from the measured energy spectrum of incident gamma-rays at 1 m above the ground.

• 대한핵의학회지
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• 제12권2호
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• pp.1-5
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• 1978

For clinical application of radioreceptor assay, we studied preliminarily the distribution of estrogen receptor in various organs of rabbit by a dextran-charcoal method using $6,7-^3H-estradiol$. The results were expressed as binding index, which is the ratio of specific estradiol receptor binding radioactivity to total radioactivity. The materials consist of 5 female rabbits and 3 male rabbits. The results were as follows: 1) Female rabbits The binding index was highest in the uterine tissue. This binding index of the uterine tissue was 9.4 times that of the liver, 21.9 times that of the kidney, 24.6 times that of the brain, 28.1 times that of the lung and 65.7 times that of the muscle. 2) Male rabbits The binding index was highest in the liver and decreased in the order of the kidney, the testis, the lung, the brain and the muscle. It is suggested that the estrogen receptor is not confined to any specific target organ but is widely distributed in the various organs, to a different degree.

• Nuclear Engineering and Technology
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• 제55권9호
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• pp.3206-3212
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• 2023

We developed a miniaturized multi-dimensional radiation sensor system consisting of an inorganic scintillator array and plastic optical fibers. This system can be applied to remotely obtain the radioactivity distribution and identify the radionuclides in radioactive waste by utilizing a scanning method. Variation in scintillation light was measured in two-dimensional regions of interest and then converted into radioactivity distribution images. Outliers present in the images were removed by using a digital filter to make the hot spot location more accurate and cubic interpolation was applied to make the images smoother and clearer. Next, gamma-ray spectroscopy was performed to identify the radionuclides, and three-dimensional volume scanning was also performed to effectively find the hot spot using the proposed array sensor.

• 한국수산과학회지
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• 제1권1호
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• pp.51-53
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• 1968

1. 부산, 공수, 일광, 월내의 4개 지점의 해수의 방사능을 G.M. counter에 의해서 측정하고, 그때의 수질의 다른 요인도 아울러 규정하여 이와 함께 그 변화를 비교하였다. 2. Radioactivity는 Salinity에 비례하여 증감하였다. 그것은 염분속의 K와 밀접한 관계가 있다고 생각된다.

• Journal of Radiation Protection and Research
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• 제30권4호
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• pp.167-174
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• 2005

The concentrations of natural and artificial radionuclides in soil and gamma ray dose rate in air at 233 locations in Korea have been determined. The national mean concentrations of $^{232}Th,\;^{226}Ra,\;^{40}K,\;^{137}Cs\;and\;^{90}Sr$ in soil were $60{\pm}31,\;33{\pm}14,\;673{\pm}238,\;35{\pm}9.3\;and\;5.0{\pm}3.4\;Bq\;kg^{-1}$, respectively. The mean gamma-ray dose rate at 1 m above the ground was $7918\;nGy\;h^{-1}$. $^{137}Cs$ concentration had highly significant correlation with organic matter content and cation exchange capacity. $^{90}Sr$ concentration had slightly coherent with pH. The results have been compared with other global radioactivity and radiation measurements.

• 대한방사선기술학회지:방사선기술과학
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• 제4권1호
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• pp.55-62
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• 1981

This study was conducted, during the period of 20-30th, July in 1981, to survey measurement methods in thyroid uptake rate test in Seoul city. The results were summarized as follows: 1. For the great part of nuclear medcine department, a mount of radioiodine($^{131}I$) administrated to the patients was $50-100{\mu}Ci$ in thyroid uptake rate test. 2. Distribution of scintillation, counter with crystal size of $1\frac{1}{2}inch$ was 43%, 3inch(22%), 2.5inch(14%) and $2\frac{1}{2}inch$ was 7% in RAI uptake rate test. 3. When RAI uptake rate test was performed, distribution of collimator in use was flat field type collimator(78%) in general and cylindrical type collimator was 22%. 4. High voltage applied to the P-M tube was $900{\sim}1000V$(50%) and most units provided $3{\sim}15%$ of the window range for the $^{131}I$ peak $\gamma-ray$ energy. 5. Distribution on the use of neck phantom for measurements standard solution was 57% and distribution of b filter in use for room background counts and extrathyroidal tissue was 43% and 50%. 6. The distance between the counter and the source was 25cm(58%) in measuring radioactivity of standard solution, thyroid tissue and background radioactivity count. 7. The early uptake measurements(2, 4, 6 hours) are done after administration of the radioiodine dose and also 24-hour and 48-hour uptake measurements are done in routine test.