• Title/Summary/Keyword: ${gamma}K$

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A Study of Gamma-ray Weapon (Gamma-ray 무기 연구)

  • Han, Dong Yoon
    • Journal of the Korea Institute of Military Science and Technology
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    • v.20 no.1
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    • pp.72-80
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    • 2017
  • Gamma-ray has some advantages as a weapon: it has the ability to transmutate matter, high penetrability through materials, and it is very harmful to living things. So it is worth to study the features of gamma-ray weapon in order to utilize it. Such abilities were simulated on the basis of Monte Carlo simulation program GEANT4. For the simulation conceptual design of gamma-ray weapon was conducted. High energy electrons, which were necessary for the high energy gamma-rays, were produced by linear electron accelerator, of which the parameters were derived from the Pohang Light Source(PLS-II). Gamma-rays were get by bremsstrahlung mechanism. The spectra of gamma-rays, that were measured at distances of 500 m, 1000 m, 1500 m and 2000 m, were gained by GEANT4.

Chemically synthesized polyester for use as biodegradable polymers (생분해성 고분자 폴리에스테르의 합성)

  • Lee, Chan Woo
    • Textile Coloration and Finishing
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    • v.8 no.4
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    • pp.19-24
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    • 1996
  • Poly(3-hydroxybutylate) 및 그들 유도체의 화학적 합성을 위해 ${\gamma}$-butyrolactone(${\gamma}$BL)과 ${\gamma}$-valerolactone(${\gamma}$VL)을 사용 ${\gamma}$-butyrolactone($\beta$BL) 과의 개환중합을 시도했다. 공중합체는 5원황 락톤 단위를 포함한 코폴리에스테르를 $BF_{3}$. $OR_{t2}$ 촉매하에서 고상(bluk state)중합에 의해 얻었고, 이러한 방법으로 합성한 코폴리머의 구조를$^{1}H NMR$$^{13}C NMR$분석법으로 결정했다. 그결과 $\beta$BL, ${\gamma}$BL과 ${\gamma}$VL의 첨가비가 증가함에 따라 수율은 저하되었고, 또한 ${\gamma}$VL의 경우 4HV의 증가가 34~35%가 한계로써, ${\gamma}$VL의 첨가비가 0.5 (${\gamma}$VL/$\beta$VL=50/50)보다 증가 할지라도 안정상태를 유지하였다.

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Effects of poly-$\gamma$-glutamic acid on serum and brain concentrations of glutamate and GABA in diet-induced obese rats

  • Lee, Hye-Sung;Chang, Moon-Jeong;Kim, Sun-Hee
    • Nutrition Research and Practice
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    • v.4 no.1
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    • pp.23-29
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    • 2010
  • Poly-gamma-glutamic acid ($\gamma$-PGA) is a mucilaginous and biodegradable compound produced by Bacillus subtilis from fermented soybeans, and is found in the traditional Korean soy product, cheongkukjang. This study was carried out to evaluate the effects of $\gamma$-PGA from a food source on the concentration of the neurotransmitter GABA and its metabolic precursor glutamate in diet-induced obese rats. Eight-week old male Sprague-Dawley rats (n=60) were used. The rats were divided into two groups and obesity was induced by providing either a 10% control fat or 45% high fat diet for 5 weeks. The rats were then blocked into 6 groups and supplemented with a 0.1% $\gamma$-PGA diet for 4 weeks. After sacrifice, brain and serum GABA and glutamate concentrations were analyzed by high performance liquid chromatography with fluorometric detection. The rats fed the high fat diet had significantly increased body weights. $\gamma$-PGA supplementation significantly increased serum concentrations of glutamate and GABA in the control fat diet groups while this effect was not found in the high fat groups. In the brain, glutamate concentrations were significantly higher in the $\gamma$-PGA supplemented groups both in rats fed the normal and high fat diets than in the no $\gamma$-PGA controls. GABA concentrations showed the same tendency. The results indicated that $\gamma$-PGA intake increased GABA concentrations in the serum and brain. However, the effects were not shown in obese rats.

Effect of γ-oryzanol on Proliferation and Apoptosis of AGS Human Gastric Carcinoma Cell (감마 오리자놀의 위암세포증식억제 및 세포사멸 유도 효능)

  • Shin, Eun Ju;Chung, Sangwon;Hwang, Jin-Taek
    • KSBB Journal
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    • v.32 no.2
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    • pp.83-89
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    • 2017
  • Gamma (${\gamma}$)-oryzanol is a substance abundant in rice, which is widely cultivated in Asian countries. In this study, we evaluated the effect of ${\gamma}$-oryzanol treatment on proliferation and apoptosis of AGS human gastric carcinoma cells. AGS cells were treated with ${\gamma}$-oryzanol for 72 h in a dose dependent manner. Treatment of ${\gamma}$-oryzanol (50, 100, and $200{\mu}g/mL$) resulted in decreased AGS cell proliferation and increased number of cells in the sub-G1 population. Additionally, apoptotic cells were investigated by annexin V staining and mitochondrial membrane potential assays. Our results indicated that ${\gamma}$-oryzanol treatment increased the number of annexin V-positive cells and depolarized cells. This demonstrated that ${\gamma}$-oryzanol is effective for the induction of apoptosis in AGS cells. We next examined the expression of promising anticancer drug target molecules, including PTEN and HSP90. We found that treatment of ${\gamma}$-oryzanol induced the expression of PTEN in AGS cells. Under the same treatment conditions, ${\gamma}$-oryzanol reduced the expression of HSP90 in AGS cells. These results suggest that ${\gamma}$-oryzanol-induced apoptosis was accompanied by changes in regulation of PTEN and HSP90 in AGS cells. Taken together, ${\gamma}$-oryzanol could be used as a functional substance for the prevention of gastric cancer.

Development of Neutron Induced Prompt γ-ray Spectroscopy System Using 252Cf (252Cf 선원을 이용한 즉발감마선 계측시스템 구성)

  • Park, Yong-Joon;Song, Byung-Chul;Jee, Kwang-Yong
    • Analytical Science and Technology
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    • v.16 no.1
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    • pp.12-24
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    • 2003
  • For the design and set-up of neutron induced prompt ${\gamma}$-ray spectroscopy system using $^{252}Cf$ neutron source, the effects of shielding and moderator materials have been examined. The $^{252}Cf$ source being used for TLD badge calibration in Korea Atomic Energy Research Institute was utilized for this preliminary experiment. The ${\gamma}$-ray background and prompt ${\gamma}$-ray spectrum of the sample containing Cl were measured using HPGe (GMX 60% relative efficiency) located at the inside of the system connected to notebook PC at the outside of the system (about 20 meter distance). The background activities of neutron and ${\gamma}$-rays were measured with neutron survey meter as well as ${\gamma}$-ray survey meters, respectively and the system was designed to minimize the activities. Prompt ${\gamma}$-ray spectrum was measured using ${\gamma}$-${\gamma}$ coincident system for reduce the background and the continuum spectrum. The optimum system was designed and set up using the experimental data obtained.

The Usefulness of Pleural IFN-$\gamma$ Level in Differential Diagnosis of Tuberculous Pleural Effusion and Malignant Pleural Effusion (결핵성 흉막염과 악성 흉수의 감별진단에 있어서 흉수 IFN-$\gamma$ 측정의 유용성)

  • Kim, Myung-Sun;Yang, Sung-Eun;Chi, Hyun-Sook;Kim, Woo-Sung;Kim, Won-Dong
    • Tuberculosis and Respiratory Diseases
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    • v.45 no.2
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    • pp.280-289
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    • 1998
  • Background: It is sometimes difficult to differentiate tuberculous pleural effusion from malignant pleural effusion by clinical symptoms, signs, by routine tests of pleural fluid, and by pathologic studies. And recently, it was discovered that cytokines such as IL-2, IFN-$\gamma$, TNF-$\alpha$ are elevated in tuberculous pleural fluid, and there have been several attempts to diagnose tuberculous pleural effusion by using these immunological mediators. There are several studies regarding the diagnostic value of IFN-$\gamma$, and there are two studies in Korea. But the diagnostic values of IFN-$\gamma$ in these studies were slightly lower than those in other countries. To compare the diagnostic value of IFN-$\gamma$ with those of CEA and ADA, and to determine the sensitivity and specificity of IFN-$\gamma$ in Korean, we mesured IFN-$\gamma$, CEA level and ADA activity in pleural effusions. Methods: ADA activity, IFN-$\gamma$ level and CEA level as well as cell count, differential count, and biochemical assays such as protein content and lactate dehydrogenase were measured in 40 cases of tuberculous pleuritis and 42 cases of malignant pleural effusion. Results: Tuberculous pleural fluid showed higher levels of IFN-$\gamma$ and ADA ($832.6{\pm}357.2$ pg/ml and $82.5{\pm}25.9$ U/L, respectively) than those of malignant pleural effusion ($2.6{\pm}8.0$ pg/ml and $19.2{\pm}10.9$ U/L, respectively) (p<0.01). Malignant pleural effusions showed higher median value (102.2 ng/ml) than tubercalous pleural effusions (1.8 ng/ml) (p<0.01). The sensitivities of IFN-$\gamma$, ADA, CEA were 0.97, 0.87, 0.67 and the specificities of IFN-$\gamma$, ADA, CEA were 1.0, 0.97, 1.0, respectively. There was no significant correlation between ADA activity and IFN-$\gamma$ level. Conclusion: This study showed that IFN-$\gamma$ test would be a very useful clinical test for differential diagnosis of tuberculous pleuritis and malignant pleural effusion because it is very sensitive and specific, although it is an expensive test.

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PPAR-Gamma Pro12Ala Polymorphism and Gastric Cancer Risk in a Turkish Population

  • Canbay, Emel;Kurnaz, Ozlem;Canbay, Bahar;Bugra, Dursun;Cakmakoglu, Bedia;Bulut, Turker;Yamaner, Sumer;Sokucu, Necmettin;Buyukuncu, Yilmaz;Yilmaz-Aydogan, Hulya
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.11
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    • pp.5875-5878
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    • 2012
  • Background: Peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$) is a ligand dependent transcription factor involved in various processes, including carcinogenesis. We aimed to investigate any possible association of the $PPAR{\gamma}$ Pro12Ala (rs1801282) polymorphism with risk of developing gastric cancer (GC). Patients and Methods: A hospital based case control study was designed covering 50 patients with GC and 120 healthy controls. The frequencies of $PPAR{\gamma}$ Pro12Ala (rs1801282) were determined using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. Results: The Ala12 allele of the $PPAR{\gamma}$ Pro12Ala G gene was associated with a 1.95 fold increased risk of GC development (p: 0.022; 95% CI: 1.58-2.40). Subgroup analyses showed that the same allele was also associated with metastasis (p: 0.000; OR:4.09; 95%CI:2.273-7.368) and differentiation (p: 0.004; OR:1.95; 95%CI:1.335-2.875) in patients with GC. Conclusion: This study suggests that the $PPAR{\gamma}$ Pro12Ala G (Ala12) allele might be associated with development, differentiation and metastatic process of GC in the Turkish population. Further studies conducted in larger study groups and in different ethnic populations will be needed to clarify the exact role of the $PPAR{\gamma}$ Pro12Ala polymorphism in GC.

Interleukin-$32{\gamma}$ Transgenic Mice Resist LPS-Mediated Septic Shock

  • Kim, Sun Jong;Lee, Siyoung;Kwak, Areum;Kim, Eunsom;Jo, Seunghyun;Bae, Suyoung;Lee, Youngmin;Ryoo, Soyoon;Choi, Jida;Kim, Soohyun
    • Journal of Microbiology and Biotechnology
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    • v.24 no.8
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    • pp.1133-1142
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    • 2014
  • Interleukin-32 (IL-32) is a cytokine and inducer of various proinflammatory cytokines such as $TNF{\alpha}$, IL-$1{\beta}$, and IL-6 as well as chemokines. There are five splicing variants (${\alpha}$, ${\beta}$, ${\gamma}$, ${\delta}$, and ${\varepsilon}$) and IL-$32{\gamma}$ is the most active isoform. We generated human IL-$32{\gamma}$ transgenic (IL-$32{\gamma}$ TG) mice to express high level of IL-$32{\gamma}$ in various tissues, including immune cells. The pathology of sepsis is based on the systemic inflammatory response that is characterized by upregulating inflammatory cytokines in whole body, particularly in response to gram-negative bacteria. We investigated the role of IL-$32{\gamma}$ in a mouse model of experimental sepsis by using lipopolysaccharides (LPS). We found that IL-$32{\gamma}TG$ mice resisted LPS-induced lethal endotoxemia. IL-$32{\gamma}$ reduced systemic cytokines release after LPS administration but not the local immune response. IL-$32{\gamma}TG$ increased neutrophil influx into the initial foci of the primary injected site, and prolonged local cytokines and chemokines production. These results suggest that neutrophil recruitment in IL-$32{\gamma}TG$ occurred as a result of the local induction of chemokines but not the systemic inflammatory cytokine circulation. Together, our results suggest that IL-$32{\gamma}$ enhances an innate immune response against local infection but inhibits the spread of immune responses, leading to systemic immune disorder.

Antioxidative Properties of Ethanolic Extracts from Flowering Cherry (Prunus serrulata L. var. spontanea Max. wils.) Fruit with Various Doses of Gamma Radiation (감마선 조사선량에 따른 버찌(Fruit of Prunus serrulata L. var. spontanea Max. wils.) 에탄올 추출물의 항산화활성)

  • Kim, Kyung-Hee;Jo, Ji-Eun;Lee, Seong-A;Yook, Hong-Sun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.40 no.10
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    • pp.1378-1383
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    • 2011
  • This study investigated the antioxidant activity of ethanolic extracts of 1~20 kGy-gamma irradiated flowering cherry fruit (Prunus serrulata L. var. spontanea Max. wils.). The total phenolic compound content was highest (30.35 mg/g) in the 10 kGy sample, but there was no consistent trend matching the increase or decrease of gamma irradiation. Radical scavenging activity using DPPH (2,2-diphenyl-1-picrylhydrazyl) showed that gamma-irradiated samples were better than non-irradiated samples and that the 10 kGy-gamma irradiated sample was the best ($IC_{50}$ 327.52 ppm). In reducing power, gamma-irradiated samples induced higher activities than non-irradiated samples at concentrations below 2.5 mg/mL, and the sample with the highest activity was the 20 kGy-gamma irradiated sample. In nitrite-scavenging ability, both gamma-irradiated and non-irradiated samples showed high activity (73~94%) at pH 1.2, 3.0, and 4.2. Also, the nitrite-scavenging ability of gamma-irradiated samples was significantly different from that of the control at pH 1.2. The FRAP value of the 3 kGy-irradiated sample also showed the highest value of 0.38 mM. Our results indicate that gamma irradiating the ethanolic extracts of flowering cherry fruit increases the antioxidant activity at some of the radiation doses. Therefore, it suggests that gamma irradiation could increase biological activity and be used effectively in food manufacturing and related industries.