• Journal of Korean Neurosurgical Society
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• v.64 no.1
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• pp.13-22
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• 2021

Objective : High precision and accuracy are expected in gamma knife radiosurgery treatment. Because of the requirement of clinically applying complex radiation and dose gradients together with a rapid radiation decline, a dedicated quality assurance program is required to maintain the radiation dosimetry and geometric accuracy and to reduce all associated risk factors. This study investigates the validity of Leksell Gamma plan (LGP)10.1.1 system of 5th generation Gamma Knife Perfexion as modified variable ellipsoid modeling technique (VEMT) method. Methods : To verify LGP10.1.1 system, we compare the treatment plan program system of the Gamma Knife Perfexion, that is, the LGP, with the calculated value of the proposed modified VEMT program. To verify a modified VEMT method, we compare the distributions of the dose of Gamma Knife Perfexion measured by Gafchromic EBT3 and EBT-XD films. For verification, the center of an 80 mm radius solid water phantom is placed in the center of all sectors positioned at 16 mm, 4 mm and 8 mm; that is, the dose distribution is similar to the method used in the x, y, and z directions by the VEMT. The dose distribution in the axial direction is compared and analyzed based on Full-Width-of-Half-Maximum (FWHM) evaluation. Results : The dose profile distribution was evaluated by FWHM, and it showed an average difference of 0.104 mm for the LGP value and 0.130 mm for the EBT-XD film. Conclusion : The modified VEMT yielded consistent results in the two processes. The use of the modified VEMT as a verification tool can enable the system to stably test and operate the Gamma Knife Perfexion treatment planning system.

• Tuberculosis and Respiratory Diseases
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• v.56 no.6
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• pp.611-618
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• 2004

Background : Idiopathic pulmonary fibrosis(IPF), a subtype of IIP(idiopathic interstitial pneumonia), is a fatal disease with a 3-5 year median survival. Many attempts at treating this condition have failed to demonstrate a survival benefit in IPF. Recently Ziesche et $al^{12}$ reported the efficacy of IFN-${\gamma}$ for treating IPF but there is still some controversy. The aim of this study was to determine the efficacy of IFN-${\gamma}$ in patients with advanced IPF who had not been responsive to steroid and cytotoxic agents. Method : Nine patients with advanced IPF(age: $55.4{\pm}15.3$ years, Male: Female=8:1) were enrolled. One year treatment regime with 2 million IU of IFN-${\gamma}$ administered subcutaneously three times a week, and low dose prednisolone(10-30 mg/d) was also used. In the case of a definite aggravation and serious side effects, the IFN-${\gamma}$ was discontinued. During the IFN-${\gamma}$ trial, a pulmonary function test and chest radiography were checked every three month throughout the study. Result : 1) Among 9 patients, only 4 patients were able to complete the 12 month treatment with IFN-${\gamma}$, and 5 patients died during the treatment period. 2) No improvement either in the respiratory symptoms or pulmonary functions were observed any of the patients, even in those who completed the 12 months trial of IFN-${\gamma}$, 3) At the time of IFN-${\gamma}$ trial, the survivors who finished the IFN-${\gamma}$ treatment for 12 months had a higher oxygen level($81.3{\pm}2.8$ vs. $67.4{\pm}8.4$, P=0.024) and a better pulmonary function(FVC: $61.3{\pm}5.1$ % predicted vs. $45.7{\pm}12.3%$, P=0.048, and $D_Lco$: $45.0{\pm}5.0%$ predicted vs. $30.8{\pm}11.2%$, P=0.048) than the non-survivors. Conclusion : Our data suggested that IFN-${\gamma}$ therapy was not effective in the patients with advanced IPF refractory compared with other therapeutic agents. Furthermore, these results suggest that severe impairment of the pulmonary function and hypoxemia during the IFN-${\gamma}$ therapy requires special attention.

• Journal of Life Science
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• v.28 no.7
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• pp.765-771
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• 2018

Peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$) is a key transcription factor that regulates adipogenesis, and epigenetic control of $PPAR{\gamma}$ is of great interest in obesity-inhibition research. Our previous study showed that CACUL1 (CDK2-associated cullin domain 1) acts as a corepressor that inhibits $PPAR{\gamma}$ transcriptional activity and adipocyte differentiation. Here, we investigated the roles of protein arginine methyltransferase 5 (PRMT5), a novel binding partner of CACUL1, in regulating $PPAR{\gamma}$. The interaction between PRMT5 and CACUL1 was shown by immunoprecipitation assay in vivo and GST pulldown assay in vitro. As shown by luciferase reporter assay, PRMT5 and CACUL1 cooperated to inhibit the transcriptional activity of $PPAR{\gamma}$. The suppressive role of PRMT5 in adipogenesis was examined by Oil Red O staining using 3T3-L1 cells, which stably overexpress or deplete PRMT5. Overexpression of PRMT5 suppresses $PPAR{\gamma}$-mediated adipogenesis, whereas PRMT5 knockdown increases lipid accumulation in 3T3-L1 cells. Consistently, PRMT5 attenuates the expression of Lpl and aP2, the target genes of $PPAR{\gamma}$, as demonstrated by RT-qPCR analysis. Overall, these results suggest that PRMT5 interacts with CACUL1 to impair the transcriptional activity of $PPAR{\gamma}$, leading to the inhibition of adipocyte differentiation. Therefore, the regulation of PRMT5 enzymatic activity may provide a clue to develop an anti-obesity drug.

• IMMUNE NETWORK
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• v.5 no.1
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• pp.23-29
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• 2005

Background: Interleukin-7 receptor (IL-7R) ${\alpha}$-deficient mice have small numbers of B cells and ${\alpha}{\beta}$T cells in periphery, they totally lack ${\gamma}{\delta}$T cells. In addition, the V-J recombination and transcription of TCR ${\gamma}$ genes is also severely impaired in IL-7R ${\alpha}$-deficient mice. Stat5, a signaling molecule of the IL-7R, induces germline transcription in the TCR ${\gamma}$ locus, and promotes V-J recombination and ${\gamma}{\delta}$T cell development. However, the roles for IL-7R signaling pathway in thymic or extrathymic ${\gamma}{\delta}$T cell development are largely unknown. Methods: To clarify the role of the IL-7 receptor in proliferation and survival of ${\gamma}{\delta}$T cells, we introduced the TCR ${\gamma}{\delta}$ transgene, $V_{{\gamma}2}/V{\delta}_5$, into IL-7R ${\alpha}$-deficient mice, and investigated the development of ${\gamma}{\delta}$T cells. Results: We found that $V_{{\gamma}2}/V{\delta}_5$ transgene restored ${\gamma}{\delta}$T cells in the epithelium of the small intestine (IEL) but not in the thymus and the spleen. Further addition of a bcl-2 transgene resulted in partial recovery of ${\gamma}{\delta}$T cells in the thymus and the spleen of these mice. Conclusion: Taken together, this study revealed that the IL-7R ${\alpha}$ is indispensable for proliferation and survival mainly in thymic ${\gamma}{\delta}$T cell development.

• Korean Journal of Food Science and Technology
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• v.43 no.5
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• pp.553-557
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• 2011

Garlic specific organic compounds were separated and purified using a recycling preparative high-performance liquid chromatography (HPLC) from blanched garlic cloves. Identification of the compounds involved comparing the previously reported HPLC retention times as well as other identification methods including $^1H$- and $^{13}C$-nuclear magnetic resonance and liquid chromatography-mass spectrometry. The yields of garlic specific organic compounds were 12.2, 42.5, 1.6, 1.2, and 4.8% on wet weight basis of garlic for alliin(S-allyl-L-cysteine sulfoxide), isoalliin(S-1-propenyl-L-cysteine sulfoxide), ${\gamma}$-glutamyl-S-allylcysteine, ${\gamma}$-glutamyl-S-1-propenylcysteine and ${\gamma}$-glutamyl-phenylalanine, respectively. All the compounds, except for ${\gamma}$-glutamylphenylalanine, contained sulfur.

• Journal of Periodontal and Implant Science
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• v.26 no.1
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• pp.216-229
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• 1996

Interferon(IFN) is a sort of glycoproteins that are produced by activated lymphocyte, monocyte and fibroblast. IFN has anti-viral effects, immuno-defensive mechanism and regulating properties to the several kinds of cells that includes affect on the bone formation and resorption. The effect of IFN on the osteoclast & other tissue cells has been studied in a number of researchers with the limited reports on the osteoblast. The purpose of this study was to evaluate the effects of IFN on the osteoblastic function. The MC3T3/El cell(Mouse osteoblast) was incubated in ${\alpha}-minimum$ essential medium containing 10% FBS. To detect the cytotoxic effect of $IFN-{\gamma}$ on osteoblast, the cells were cultured in 96-well plate to which $IFN-{\gamma}$ of various concentrations were added for 2 days. After staining with trypan blue, total cells and living cells were counted under microscope. To determine the activity of alkaline phosphataset(ALP), various concentrations of $IFN-{\gamma}$ were treated to culture medium, and biochemical assay was performed. $IFN-{\gamma}$ and $IFN-{\gamma}$ plus cycloheximide were added to culture medium separately and then ALP activity were determined. To detect the effect of the $IFN-{\gamma}$ on the bone formation of osteoblast, long-term culture was performed, and calcified nodule formation were observed using von Kossa's staining. After the addition of $IFN-{\gamma}$ with various concentrations to the medium, no cytotoxic effect of $IFN-{\gamma}$ was detected at any concentration. The significant increase in ALP activity of osteoblast were found the concentration of $IFN-{\gamma}$ 500-2500U/ml and the culture time of 24-48 hours respectively. The enhancement of ALP activity by $IFN-{\gamma}$ of osteoblast was decreased significantly by the treatment of cycloheximide. After long-term culture of osteoblast, the nodule formation was found to be increased in number and density by the addition of 500 U/ml $IFN-{\gamma}$. These results suggest that $IFN-{\gamma}$ was affected on the bone formation of osteoblast. Forthemore this kind of study or $IFN-{\gamma}$ to osteoblast will be held continuously.

• Korean Journal of Materials Research
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• v.11 no.6
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• pp.502-507
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• 2001

The effect of solidification rate on the microstructure of directionally solidified IN792+ Hf superalloy has been studied. Solidification sequence and precipitation behavior of the alloy have been analysed by microstructural observation. The script carbide transformed to faceted carbide with decreasing solidification rates. The incorporation of ${\gamma}$ phase into the faceted carbide was due to dendritic growth of carbides. Some elongated carbide bars formed along the grain boundaries at a solidification rate of 0.5$\mu\textrm{m}$/s. Two zones, ${\gamma}$' forming elements enriched zone and depleted zone, were found in the residual liquid area. Eutectic ${\gamma}$/${\gamma}$' nucleated in the f forming elements enriched zone. Formation of eutectic ${\gamma}$/${\gamma}$' increased the ratio of (Ti+Hf+Ta+W)/Al and induced η phase precipitation. The ratio of (Ti+Hf+Ta+W)/Al decreased at lower solidification rates due to sufficient back diffusion in the residual liquid area. Hence, the Precipitation of the η Phase efficiently suppressed at the lower solidification rate.

• Economic and Environmental Geology
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• v.9 no.3
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• pp.135-141
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• 1976

The gamma-gamma logging method appplying in geophysical research are presented in this paper_ The logging probe assembly was designed which permits changing the source-to-detector spacing while conditions of proceeding ${\gamma}-{\gamma}$ logging, which a collimated gamma ray source ($^{60}Co$, 0.5mCi and/or 2 mCi) is separated from the scintillation detector as shown in Fig. 2 and 3, size is 6.0 cm in diameter and 120.0 cm in long and the exposed parts are made of stainless steel pipe. The results is confirmed by the experiment performed mainly in granite rock where a slightly constant shape was obtained but sometimes was shown sharpness shape for the measured scattered gamma-ray intensity. Consequently, the experimental results are obtained an adequate intensity of scattered gamma-rays and favourable response to density change, and also very closely correspond to between core samples of the test boring and to used this method of ${\gamma}-{\gamma}$ logging in the test bore-hole of the strata.

• Preventive Nutrition and Food Science
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• v.12 no.3
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• pp.173-176
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• 2007

${\gamma}-Oryzanol$ is one of the chain breaking antioxidants. Both sterol (triterpene) and phenolic hydroxyl groups in the structure of ${\gamma}-oryzanol$ may be responsible for its antioxidative function. We hypothesize that ${\gamma}-oryzanol$ is more effective in preventing the autoxidation of polyunsaturated fatty acid (PUFA) than the synthetic phenolic compounds in an oil/water (O/W) emulsion system. The antioxidative effectiveness of different concentrations of ${\gamma}-oryzanol$ and synthetic antioxidants was evaluated at different incubation times (0, 4, 8, 16, and 32 h) by measuring both the formation of hydroperoxides and the decomposition product of hydroperoxides (hexanal) in each emulsion system. Overall, the order of effectiveness of various antioxidants for inhibiting the formation of hydroperoxide in the O/W emulsion was: ${\gamma}-oryzanol$> tert-butylhydroquinone (TBHQ)> butylated hydroxytoluene (BHT)> butylated hydroxyanisole (BHA). O/W emulsion with selective lower concentrations of ${\gamma}-oryzanol$ showed better effectiveness than that with higher concentration of synthetic antioxidants. However, the ability of both ${\gamma}-oryzanol$ and synthetic antioxidants to decompose hydroperoxide was similar. ${\gamma}-Oryzanol$ was more effective antioxidant than the synthetic phenolic compounds in preventing the formation of hydroperoxide in the O/W emulsion system.

• Biomedical Science Letters
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• v.10 no.2
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• pp.137-142
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• 2004

The peroxisome proliferator-activated receptor $\gamma$ (PPAR${\gamma}$) is the molecular target for a class of drugs, the antidiabetic thiazolidnediones (TZDs). The heterodimer of PPAR${\gamma}$ with retinoid X receptor (RXR) plays a central role in the regulation of adipogenesis and insulin sensitization. We synthesized two chemicals, DANA87 and DANA88, sharing structural characteristics with TZDs. Given this structural similarity, it was hypothesized that DANA87 and DANA88 may act as PPAR$\gamma$ ligands. In transient transfection assays, DANA87 and DANA88 caused slight increases in the endogenous expression of a luciferase reporter gene containing the PPAR responsive element in 3T3-L1 preadipocytes. However, DANA87 and DANA88 significantly inhibited troglitazone-induced reporter gene activation when cells were treated with a combination of DANA87 or DANA 88 and troglitazone, one of the TZDs that activate PPAR$\gamma$. These results suggest that DANA87 and DANA88 are not only weak agonists of PPAR${\gamma}$ transactivation, but also competitively antagonize troglitazone-induced PPAR$\gamma$ reporter activity.