• The Korean Journal of Nuclear Medicine
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• v.33 no.2
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• pp.172-177
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• 1999

Purpose: The purpose of this study was to ascertain whether radiation adaptive response could be induced by Tc-99m-methylene diphosphonate (Tc-99m-MDP) in peripheral lymphocytes of patients undergoing bone scintigraphy. Materials and Methods: Lymphocytes from 22 patients (6 males, 16 females, mean age $50{\pm}14$ years) were collected before and after bone scintigraphy using 740 MBq Tc-99m-MDP Lymphocytes from 10 controls (6 males, 4 females, mean age $43{\pm}7$ years) were also collected. They were exposed to challenge dose of 2 Gy gamma rays using a cell irradiator. Number of ring-form and dicentric chromosomes per 600 cells (chromosomal aberrations) was counted under the light microscope. Results: Chromosomal aberrations in patients before bone scintigraphy ($385.1{\pm}30.5$) was not different from that of controls ($367.8{\pm}36.6$). However, chromosomal aberrations in patients after bone scintigraphy was significantly decreased to $192.6{\pm}22.1$ (p=0.0001). Conclusion: Low dose gamma-irradiation by Tc-99m-MDP used for bone scintigraphy induces a cytogenetic adaptive response in peripheral lymphocytes.

• Toxicological Research
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• v.29 no.1
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• pp.21-25
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• 2013

The selective targeting of an integrin ${\alpha}_v{\beta}_3$ receptor using radioligands may enable the assessment of angiogenesis and integrin ${\alpha}_v{\beta}_3$ receptor status in tumors. The aim of this research was to label a peptidomimetic integrin ${\alpha}_v{\beta}_3$ antagonist (PIA) with $^{99m}Tc(CO)_3$ and to test its receptor targeting properties in nude mice bearing receptor-positive tumors. PIA was reacted with tris-succinimidyl aminotriacetate (TSAT) (20 mM) as a PIA per TSAT. The product, PIA-aminodiacetic acid (ADA), was radiolabeled with $[^{99m}Tc(CO)_3(H_2O)_3]^{+1}$, and purified sequentially on a Sep-Pak C-18 cartridge followed by a Sep-Pak QMA anion exchange cartridge. Using gradient C-18 reverse-phase HPLC, the radiochemical purity of $^{99m}Tc(CO)_3$-ADA-PIA (retention time, 10.5 min) was confirmed to be > 95%. Biodistribution analysis was performed in nude mice (n = 5 per time point) bearing receptor-positive M21 human melanoma xenografts. The mice were administered $^{99m}Tc(CO)_3$-ADA-PIA intravenously. The animals were euthanized at 0.33, 1, and 2 hr after injection for the biodistribution study. A separate group of mice were also co-injected with 200 ${\mu}g$ of PIA and euthanized at 1 hr to quantify tumor uptake. $^{99m}Tc(CO)_3$-ADA-PIA was stable in phosphate buffer for 21 hr, but at 3 and 6 hr, 7.9 and 11.5% of the radioactivity was lost as histidine, respectively. In tumor bearing mice, $^{99m}Tc(CO)_3$-ADA-PIA accumulated rapidly in a receptor-positive tumor with a peak uptake at 20 min, and rapid clearance from blood occurring primarily through the hepatobiliary system. At 20 min, the tumor-to-blood ratio was 1.8. At 1 hr, the tumor uptake was 0.47% injected dose (ID)/g, but decreased to 0.12% ID/g when co-injected with an excess amount of PIA, indicating that accumulation was receptor mediated. These results demonstrate successful $^{99m}TC$ labeling of a peptidomimetic integrin antagonist that accumulated in a tumor via receptor-specific binding. However, tumor uptake was very low because of low blood concentrations that likely resulted from rapid uptake of the agent into the hepatobiliary system. This study suggests that for $^{99m}Tc(CO)_3$-ADA-PIA to be useful as a tumor detection agent, it will be necessary to improve receptor binding affinity and increase the hydrophilicity of the product to minimize rapid hepatobiliary uptake.

• Journal of radiological science and technology
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• v.30 no.3
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• pp.259-263
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• 2007

For the preparation of $^{99m}Tc$-labeled RBC, $10{\sim}20\;{\mu}g/kg$ of Stannous(II) chloride and $10{\sim}40\;min$ of preparation was used. For finding out the effect of contrast agent, the blood samples were collected in three days, seven days, and 1 months after the diagnostic procedure. In the normal volunteer, the concentration of reducing agent and preparation time did not effect on the radiochemical yield. But in the patients, 10 mg of Stannous(II) chloride and 60 min incubation times was shown high radiochemical yield. Contrast agent has a significant effect on the radiochemical yield. Although the blood samples which were collected after seven days of diagnostic procedure did not effect on the radiochemical yield of $^{99m}Tc$-labeled RBC, but the radiochemical yield of $^{99m}Tc$-labeled RBC which was prepared with a sample of high concentration of contrast agent in blood led to low radiochemical yield. For these samples, the modified method showed high radiochemical yield than previous in vivo preparation method. The recommended method is followed. Blood collecting was performed at 30 minutes after injection of reducing agent, and it is centrifuged for removal of plasma. After addition of $^{99m}TcO^-_4$, sample reservoir was rotated. After addition of normal saline, and it is centrifuged for separation of saline. Then $^{99m}Tc$-labeled RBC was obtained after removal of saline.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.44 no.1
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• pp.89-94
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• 2018

In this study, water-dispersed biocellulose nanofibers (TC) were prepared via an oxidation reaction using 2,2,6,6-tetramethyl-1-piperidine-N-oxy radical (TEMPO) as a catalyst. The TC retained their unique structure in water as well as in emulsion. TC adhered to the skin surface while maintaining nanofibrous structures, providing inherent functions of biocellulose, such as high tensile strength and high water-holding capacity. When gelatin gels as model skin were coated with TC, the hardness representing the elasticity was increased by 20% compared to untreated gelatin gel because TC could tightly hold the gelatin structure. When porcine skin was treated with TC and TC-contained O/W emulsion, the initial water contact angles of TC were lower than other materials, and dramatically decreased over time as water penetrated the fibrous structure of the TC film. Characterization of TC on the skin surface offered insight into the function of nanofibers on the skin, which is important for their applications with respect to fiber-cosmetics.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.9
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• pp.4342-4348
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• 2013

The present study was intended to reveal the relationships between serum lipid levels and various factors of obesity and blood pressure. The study subjects were 1,838 adult women measured at a mass health screening during the period from January through December, 2011. TC, TG, HDL-C, LDL-C, SBP, DBP, degree of obesity, body fat rate were measured and the relation between these obesity and blood pressure measurements to serum lipid levels were studied. As a results, TC, TG, LDL-C, body fat rate and degree of obesity increased linearly with advancing age. TC, TG and LDL-C increased linearly with increasing blood pressure, and these values were higher in hypertension group than that of normal group. TC, TG and SBP increased linearly with increasing degree of obesity, and these values were higher in obesity group than that of normal group. HDL-C decreased linearly with increasing degree of obesity, and these values were lower in obesity group than that of normal group. TC, TG, HDL-C, degree of obesity, body fat rate was positive correlation with each others, but these values negatively correlated to HDL-C. Principal component analysis, showed that subjects could be divided into the group having the hypertensive group(1st principal component), the obesity group(2nd principal component), the hyperlipidemia group(3rd principal component), and HDL-C(4th principal component). In multiple regression analysis, age, TC, TG and body fat rate were affected to HDL-C. Above results suggest that higher the degree of obesity and blood pressure, the higher the serum lipid levels.

• Journal of the Korean Vacuum Society
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• v.16 no.6
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• pp.397-404
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• 2007

International Standardization for Vacuum pumps, vacuum instruments, and vacuum components has been established at ISO/TC 112 which is a technical committee of ISO (International Organization for Standardization) in the area of vacuum technology. This report shortly summarizes the structure of ISO/TC 112 and its activities on the standardization for vacuum technology. Also it introduces the brief contents of "specifications for hot cathode ionization gauges" and"Test procedure for vacuum valves" which are recently accepted as new proposals. These information on ISO/TC 112 would contribute to activate the development of vacuum technology as well as the participation for the international standardization in Korea.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.1
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• pp.59-68
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• 2016

For comparison of tetracycline-resistant ($Tc^R$) genes, we obtained 21 and 14 $Tc^R$ Staphylococcus spp. from marine environment and human patient, respectively. Although all isolates from human were identified as Staphylococcus aureus, higher proportion of $Tc^R$ isolates (12 out of 14) from human were utilizing tet(M) gene compared to that of $Tc^R$ isolates (6 out of 21) from marine environment. Additionally, collaborated utilization of tet(M) and erm(A) in $Tc^R-Em^R$ S. aureus in human patient, but not in $Tc^R$ Staphylococcus spp. isolates from marine environment was also characterized. Based on the nucleotide sequence of transposon related to $Tc^R$ gene, we confirmed the origin of tet(M) gene in $Tc^R$ Staphylococci isolated from marine environments and human are derived from Tn916/1545-like and Tn5801 transposon, respectively. It is the first report showing the presence of Tn5801 in all $Tc^R$ S. aureus carrying tet(M) in human patient. Alignment of the fully sequenced tet(M) from marine environmental isolates was also agreed with the determined transposons by showing the genomic mosaic structure composed with three genomic parts from Tn916/1545 and unknown transposons. Genetic characteristics of these tet(M) in environmental isolates were similar to each other but different from those in isolates from human showing only tet(M) from Tn916/5801 type. It may imply the presence of less dramatic communication of antibiotic resistant genes between Staphylococci isolated from marine environment and human.

• 한국초전도학회:학술대회논문집
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• v.10
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• pp.85-85
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• 2000

The normal state of high-Tc superconducting materials has been believed to contain important clues to finding the correct mechanism of the high-Tc superconductivity. One example is the existence of pseudogap in the normal state even above Tc, as observed in various measurements such as photoemission spectroscopy and tunneling conductance. In this pseudogap regime the existence of preformed pairs only with local phase coherence has been debated. Recently Choi, Bang, and Campbell[1] have proposed the occurrence of the zero-bias conductance enhancement due to Andreev quasiparticle reflection from the preformed pairs even with the local phase coherence. In this study we examine the zero-bias enhancement of the differential conductance near or slightly above Tc, using c-axis tunneling in mesa structure of Bi2Sr20a0u208+d single crystals. In slightly overdoped samples zero-bias conductance enhancement (ZBCE) has been observed over a range of 2 K above Tc. In contrast, in underdoped samples with Tc${\sim}$72K the ZBCE appears over a range of 5-6 K above Tc, a much wider temperature range than in overdoped samples. This result may pose as positive signs of the existence of prefurmed pairs in the normal state of high- Tc superconducting materials.

• Journal of Nutrition and Health
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• v.46 no.4
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• pp.324-331
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• 2013

We investigated dietary effects of green tea powder (GTP) on plasma lipids, platelet aggregation, hemolysis, plasma TBARS, and liver enzymes. Thirty one volunteer diving women living on Jeju island consumed 4 g green tea powder daily for a period of four weeks and data for the study subjects were analyzed on the basis of diagnostic criteria for blood pressure (BP)(${\geq}$ 140/90 mmHg), plasma total cholesterol (TC)(${\geq}$ 200 mg/dL), and triglyceride (TG)(${\geq}$ 150mg/dL). Subjects with high BP had significantly higher TC and TG than those with normal BP. Subjects with higher TC had higher TG, and those with higher TG had lower HDL cholesterol. Platelet aggregation in the initial slope was significantly higher in subjects with normal BP, normal TC, or normal TG than their counterparts in high BP, TC, and TG. HDL cholesterol after GTP intake increased only in subject groups with normal BP, normal TC, or normal TG, and plasma TG after GTP intake decreased only in groups with higher BP, higher TG, or higher TC. Plasma TC and TG in subjects with normal BP increased after GTP intake. GTP intake caused a decrease in the initial slope of platelet aggregation in all subject groups with little effect on maximum aggregation. Total bilirubin showed a significant increase and GOT increased in all subject groups after GTP intake. Beneficial effects of short term intake of green tea powder might differ depending on the subject conditions in terms of blood pressure, plasma lipids, and other cardiovascular conditions. However, with the hypolipidemic, antithrombotic, and antioxidant actions of its bioactive flavonoids, long term usage of GTP or brewed green tea may provide preventive effects against cardiovascular disease.

• The Korean Journal of Nuclear Medicine
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• v.29 no.1
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• pp.92-97
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• 1995

감염병소와 진단을 위해 여러 방사성성핵종 표지 사람비특이항체들이 임상이용되었으나, $^{123}I,\;^{99m}Tc,\;^{111}In$등 표지 핵종과 표지방법에 따른 체내동태의 차이에 대한 자료가 필요하며, 감염병소의 진단에 표준적으로 이용되어지던 $^{111}In$-oxine표지백혈구와 비교평가도 요구된다. 저자들은 $10^9$개의 포도상구균을 좌측 대퇴부에 주사하여 농양을 유발한 백서에서 $^{123}In$ 표지, iminothiolane을 이용한 $^{99m}Tc$ 표지, DTPA이용 $^{111}In$ 표지 사람비특이항체와 $^{111}In$-oxine 표지 백혈구의 체내동태 및 농양섭취율을 비교하였다. $^{123}In$-IgG는 갑상선 및 위의 방사능이 높아 체내 탈요드반응이 빠름이 시사되었으며, $^{99m}Tc$-iminothiolane IgG는 신장방사능이 높아 신장으로 IgG 또는 대사물이 배설됨을 알 수 있었다. $^{111}In$-oxine표지 백혈구는 간 및 비장의 방사능이 높았고, 혈액방사능 제거율이 가장 빨랐다. 주사 24시간 후의 농양섭취율은 $^{111}In$-DTPA IgG가 가장 높았고, 농양 대 혈액 방사능비는 $^{111}In$-oxine표지 백혈구가 가장 높았으며, $^{111}In$-DTPA IgG와 $^{99m}Tc$-iminothiolane IgG가 다음으로 비슷하였다. $^{111}In$-oxine표지 백혈구보다는 방사성핵종표지 IgG가 간편하게 이용될 수 있으며, $^{111}In$ 이 $^{99m}Tc$나 $^{123}In$보다 지연영상의 촬영에 유리함을 알 수 있었다.