• Investigative Magnetic Resonance Imaging
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• v.8 no.2
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• pp.94-99
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• 2004

Purpose : To investigate the signal enhancement ratio by NOE effect on in vivo $^{31}P$ MRS in human heart muscle and liver. we also evaluated the enhancement ratios of different phosphorus metabolites, which are important in 31P MRS for each organ. Materials and Methods : Ten normal subjects (M:F = 8:2, age range = 24-32 yrs) were included for in vivo $^{31}P$ MRS measurements on a 1.5 T whole-body MRI/MRS system using $^1H-^{31}P$ dual tuned surface coil. Two-dimensional Chemical Shift Imaging (2D CSI) pulse sequence for $^{31}P$ MRS was employed in all $^{31}P$ MRS measurements. First, $^{31}P$ MRS performed without NOE effect and then the same 2D CSI data acquisitions were repeated with NOE effect. After postprocessing the MRS raw data in the time domain, the signal enhancements in percent were estimated from the major metabolites. Results : The calculated NOE enhancement for liver $^{31}P$ MRS were $\alpha-ATP\;(7\%),\;\beta-ATP\;(9\%),\;\gamma-ATP\;(17\%),\;Pi\;(1\%),\;PDE\;(19\%)$ and $PME\;(31\%)$. Because there is no creatine kinase activity in liver, PCr signal is absent. For cardiac $^{31}P$ MRS, whole body coil gave better scout images and thus better localization than surface coil. In $^{31}P$cardiac multi-voxel spectra, DPG signal increased from left to right according to the amount of blood included. The calculated enhancement for cardiac $^{31}P$ MRS were : $\alpha-ATP\;(12\%),\;\beta-ATP\;(19\%),\;\gamma-ATP\;(30\%),\;PCr\;(34\%),\;Pi\;(20\%),\;(PDE)\;(51\%),\;and\;DPG\;(72\%)$. Conclusion : Our results revealed that the NOE effect was more pronounced in heart muscle than in liver with different coupling to 1H spin system and thus different heteronuclear cross-relaxation.

• Clinical and Experimental Pediatrics
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• v.45 no.3
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• pp.354-361
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• 2002

Purpose : Selective introduction of genes conferring chemosensitivity into proliferating tumor cells may be used to treat cancer. We first investigated the bystander effect of retrovirus-mediated gene transfer of herpes simplex virus thymidine kinase(HSV-TK) gene to murine neuroblstoma cell line(neuro-2a) in vitro and in vivo. Second, we examined the mechanism and its enhancement of the bystander effect in murine neuroblastoma. Methods : To investigate the bystander effect, we studied tumor growth and survival time after HSV-TK/ganciclovir(GCV) treatment in a syngenic A/J mouse neuroblastoma model by mixing various ratios of HSV-TK-expressing neuro-2a cells with wild type neuro-2a cells followed by GCV treatment. To investigate the mechanism of the bystander effect in murine neuroblastoma, immunohistochemistry using connexin 43, CD4 and CD8-specific monoclonal antibodies was analyzed. We studied whether IL-2-secreting neuro-2a cells(neuro-2a/IL-2) would potentiate the bystander effect. Results : A strong bystander effect was observed in vitro and in vivo. The bystander effect in murine neuroblastoma was dependent on the immune response rather than connexin-mediated gap junction. Neuro-2a/IL-2 treatment enhanced the bystander effect in the HSV-TK/GCV system in murine neuroblastoma model. Conclusion : We conclude that the bystander effect in murine neuroblastoma depends on immune response and is enhanced by neuro-2a/IL-2.

• Progress in Medical Physics
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• v.18 no.1
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• pp.42-47
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• 2007

Purpose: To evaluate the tracing of optic nerve tract using manganese enhanced magnetic resonance Imaging. Materials and Methods: After injecting $30{\mu}l$ of $MnCl_2(1mol)$ (1 mol) Into the retina of female New Zealand white rabbit, the contrast enhancements at major anatomical structures of optic nerve tract were evaluated by high resolution T1-weighted Images 12 hours, 24 hours, and 48 hours after $MnCl_2(1mol)$ Injection using 3D FSPGR (Fast Speiled Gradient Recalled echo) pulse sequence at 1.5T clinical MR scanner with high performance gradient system. Also, for quantitative evaluation, the signal-to-noise ratios of circular ROI on anatomical locations were measured. Results: The major structures on the optic nerve tract were enhanced after injecting $MnCl_2(1mol)$. The structures, which showed enhancement, were right optic nerve, optic chiasm, left optic tract, left lateral geniculate nucleus, left superior colliculus. The structures on the contralateral optic pathway to the right retina were enhanced whereas the structures on the ipsilateral pathway did not show enhancement. Conclusion: The Mn transport through axonal pathway of optic nerve sys)em was non- invasively observed after injecting injecting $MnCl_2$ at the retina, which is the end terminal of optic nerve system. This Mn transport seems to occur by voltage gated calcium $(Ca^{2+})$ channel and In case of direct Injection Into the retina, the fast transpori pathway of voltage gated calcium channel seems to be responsible for Mn transport.

• Korean Journal of Radiology
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• v.22 no.7
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• pp.1185-1193
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• 2021

Objective: Clear cell sarcoma of the kidney (CCSK) is the second-most common but extremely rare primary renal malignancy in children after Wilms' tumor. The aims of this study were to evaluate the imaging features that could distinguish between CCSK and Wilms' tumor and to assess the features with diagnostic value for identifying CCSK. Materials and Methods: We reviewed the initial contrast-enhanced abdominal-pelvic CT scans of children with CCSK and Wilms' tumor between 2010 to 2019. Fifty-eight children (32 males and 26 females; age, 0.3-10 years), 7 with CCSK, and 51 with Wilms' tumor, were included. The maximum tumor diameter, presence of engorged perinephric vessels, maximum density of the tumor (Tmax) of the enhancing solid portion, paraspinal muscle, contralateral renal vein density, and density ratios (Tmax/muscle and Tmax/vein) were analyzed on the renal parenchymal phase of contrast-enhanced CT. Fisher's exact tests and Mann-Whitney U tests were conducted to analyze the categorical and continuous variables, respectively. Logistic regression and receiver operating characteristic curve analyses were also performed. Results: The age, sex, and tumor diameter did not differ between the two groups. Engorged perinephric vessels were more common in patients in the CCSK group (71% [5/7] vs. 16% [8/51], p = 0.005). Tmax (median, 148.0 vs. 111.0 Hounsfield unit, p = 0.004), Tmax/muscle (median, 2.64 vs. 1.67, p = 0.002), and Tmax/vein (median, 0.94 vs. 0.59, p = 0.002) were higher in the CCSK compared to the Wilms' group. Multiple logistic regression revealed that engorged vessels (odds ratio 13.615; 95% confidence interval [CI], 1.770-104.730) and Tmax/muscle (odds ratio 5.881; 95% CI, 1.337-25.871) were significant predictors of CCSK. The cutoff values of Tmax/muscle (86% sensitivity, 77% specificity) and Tmax/vein (71% sensitivity, 86% specificity) for the diagnosis of CCSK were 1.97 and 0.76, respectively. Conclusion: Perinephric vessel engorgement and greater tumor enhancement (Tmax/muscle > 1.97 or Tmax/vein > 0.76) are helpful for differentiating between CCSK and Wilms' tumor in children aged below 10 years.

• Journal of the Korean GEO-environmental Society
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• v.16 no.11
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• pp.13-19
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• 2015

Construction materials using soil which is the most common material around us have many advantages, but their long-term durability and sensation of walking as pavements have problems. Therefore, they are used after compaction or mixed with various hardening agents such as lime and cement for strength enhancement. However, studies on the behavior of pavement materials mixed with environment-friendly hardening agents or admixtures to improve walking property are still insufficient. In this study, therefore, in order to evaluate the appropriate mixing ratio and field application characteristics of pavement materials using mixed soils with environment-friendly hardening agents and natural materials such as wood chips, mechanical tests were performed to evaluate the rational mixing ratios and the ball test was performed as an elasticity test to evaluate the field applicability. The results suggest that the content of wood chips should be selected at 1.5% or lower according to the purpose of the structure, and the hardening agent at 10~15%. The evaluation results for GB/SB coefficient ratio which indicates the walking property show that the appropriate mixing ratio of the hardening agent in terms of the sensation of walking is 15% of lower, but different mixing ratios should be chosen according to the proportion of wood chips.

• THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
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• v.3 no.1
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• pp.29-48
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• 1997

Astragalus membranaceus Bunge (黃?), Atractylodes macrocephala Loidz (白朮), Angelica sinensis(Oliv) Kiels (當歸), Lycium chinense Mill (枸杞子), Ligustrum lucidum Ail (女貞子) are Herbs that are frequently used in a lot of prescriptions to reduce the side effects of anti-cancer therapies, especially like chemotherapy and radiotherapy. The radioprotective and hemopoietic effects of these Herbs on BALB/c splenocytes and bone marrow cells are measured. In order to evaluate the Hemopoietic effects, Thymidine uptakes and secretion of colony stimulating factors(CSFs) of splenocytes and myelocytes treated with herbs were measured. Radioprotective effects were accessed by the method of immunocompetence of murine lymphocytes cultured with herbs before irradiation and with LPS, ConA after irradiation. The results are as follows. 1. The orders of Proliferative effects of herbs on splenocytes were Atractylodes macrocephala Loidz (白朮), the higest of all, Astragalus membranaceus Bunge (黃?), Angelica sinensis(Oliv) Kiels (當歸). Lycium chinense Mill (枸杞子) and Ligustrum lucidum Ait (女貞子), the lowest of all. At Optimal concentration, the proliferation ratios of herb-treated splenocytes compared to non-treated ones were like these. Atractylodes macrocephala Loidz (白朮) 44.3, Astragalus membranaceus Bunge (黃?) 17.7, Angelica sinensis(Oliv) Kiels (當歸) 10, Lycium chinense Mill (枸杞子) 6.4, Ligustrum lucidum Ait (女貞子) 2.0.(p<0.05) 2. When splenocytes were cultured during different periods, Atractylodes. macrocephala Loidz (白朮) and Astragalus membranaceus Bunge (黃?) showed the higest proliferation on 3th day, Angelica sinensis(Oliv) Kiels (當歸), Lycium chinense Mill (枸杞子) on 4th day,(p<0.05) and Ligustrum lucidum Ait (女貞子) until 5th day but with no significant increase. 3. The orders of Proliferative effects of herbs on Bone Marrow(BM) cells were Atractylodes macrocephala Loidz (白朮), the higest of all, Astragalus memhranaceus Bunge (黃?), Angelica sinensis(Oliv) Kiels (當歸), Lycium chinense Mill (枸杞子) and Ligustrum lucidum Ait (女貞子), the lowest of all too. At Optimal concentration, the proliferation ratios of herb-treated BM cells compared to non-treated ones were like these. Atractylodes macrocephala Loidz (白朮) 21.7, Astragalus membranaceus Bunge (黃?) 9.9, Angelica sinensis(Oliv) Kiels (當歸) 4.9, Lycium chinense Mill (枸杞子) 2.3, Ligustrum lucidum Ait (女貞子) 1.4(p<0.05). 4. The secretion ratio of colony stimulating factors(CSFs) of each herb-treated group, compared to control, was Atractylodes macrocephala Loidz (白朮) 9.4, Astragalus membranaceus Bunge (黃?) 9.0, Angelica sinensis(Oliv) Kiels (當歸) 4.4, Lycium chinense Mill (枸杞子) 3.8 (p<0.05) but no significant increase in Ligustrum lucidum Ait (女貞子). 5. The mitogen(ConA, LPS) stimulated-lymphocytes cultured with each herb before irradiation of 1-3 Gy showed more enhanced proliferation than control(p<0.05). When compared to each non-irradiated group of all groups, the orders of percentage increase of irradiated group were Atractylodes macrocephala Loidz (白朮), the higest of all, Astragalus membranaceus Bunge (黃?), Angelica sinensis(Oliv) Kiels (當歸), Ligustrum lucidum Ait (女貞子), Lycium chinense Mill (枸杞子). Each percentage showed significant enhancement compared to control group(p<0.05). According to the results, Atractylcdes macrocephala Loidz (白朮), Astragalus membranaceus Bunge (黃?) are suggested to be the most effective hemopoietic and radioprotective herbs, and Angelica sinensis(Oliv) Kiels (當歸), Lycium chinense Mill (枸杞子) the next, but Ligustrum lucidum Ait (女貞子) showed lower effects than expected.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.11
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• pp.157-165
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• 2018

Companies conduct R&D for continuous development and enhancement of corporate value, and obtain patents as an intangible asset resulting from this process. This study screened 103 medical device firms whose R&D information, patent information, and management performance information were all published to determine how R&D activities and patents affect corporate operational performance. The number of patents, R&D costs, company type and Inno-Biz of the company were set as independent variables, and the companies' sales, intangible assets, operating profit ratios, net profit margins, corporate ratings and profit-related financial ratios were used as dependent variables. The results confirmed that R&D expenditure had negative (-) effects on most indicators, including sales volume, operating profit ratio, and net profit ratio, while it had positive (+) [ED highlight - these are unnecessary if negative and positive are also written out.] effects only on intangible assets. Additionally, domestic patents were found to have negative (-) effects on sales, cash flow ratings, and dropped capital return, and positive (+) effects on net profit growth. Moreover, the business performance variables affected by the company characteristics were sales volume and cash flow ratings. The medical device industry is dominated by small and medium-sized businesses Although research and development activities and patents have been shown to have a negative impact on corporate management in the short term, they are expected to have a positive long-term impact when reflecting the characteristics of the medical device industry that must undergo clinical trials and authorization procedures after R&D.

• Radiation Oncology Journal
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• v.21 no.3
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• pp.216-221
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• 2003

Purpose: To investigate the modulation of radiosensitivity by celecoxib, a selective cyclooxygenase-2 (COX-2) inhibitor, on cancer cells over- and under-expressing COX-2. Materials and Methods: A clonogenic radiation survival analysis was performed on A549 human lung and MCF-7 human breast cancer cell lines incubated in both 1 and $10\%$ fetal bovine serum (FBS) containing media. The apoptosis in both cell lines was measured after treatment with radiation and/or celecoxib. Results: Celecoxib enhanced the radiation sensitivity of the A549 cells in the medium containing the $10\%$ FBS, with radiation enhancement ratios of 1.58 and 1.81 respectively, at surviving fractions of 0.1, with $30\muM\;and\;50\muM$ celecoxib. This enhanced radiosensitivity disappeared in the medium containing the $1\%$ FBS. Celecoxib did not change the radiation sensitivity of the MCF-7 cells in either media. The induction of apoptosis by celecoxib and radiation was not synergistic in either cell line. Conclwsion: Celecoxib, a selective COX-2 inhibitor, preferentially enhanced the effect of radiation on COX-2 over-expressing cancer cells compared to the cells with a low expression, and this effect disappeared on incubation of the cells during drug treatment in the medium with suboptimal serum concentration. Apoptosis did not appear to be the underlying mechanism of this radiation enhancement effect due to celecoxib on the A549 cells. These findings suggest radiosensitization by a selective COX-2 inhibitor is COX-2 dependent.

• The Plant Pathology Journal
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• v.33 no.1
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• pp.1-8
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• 2017

Seed dehiscence of ginseng (Panax ginseng C. A. Mayer) is affected by moisture, temperature, storage conditions and microbes. Several microbes were isolated from completely dehisced seed coat of ginseng cultivars, Chunpoong and Younpoong at Gumsan, Korea. We investigated the potential of five Talaromyces flavus isolates from the dehiscence of ginseng seed in four traditional stratification facilities. The isolates showed antagonistic activities against fungal plant pathogens, such as Cylindrocarpon destructans, Fusarium oxysporum, Rhizoctonia solani, Sclerotinia nivalis, Botrytis cinerea, and Phytophthora capsici. The dehiscence ratios of ginseng seed increased more than 33% by treatment of T. flavus GG01, GG02, GG04, GG12, and GG23 in comparison to control (28%). Among the treatments, the reformulating treatment of T. flavus isolates GG01 and GG04 showed the highest of stratification ratio of ginseng seed. After 16 weeks, the reformulating treatment of T. flavus isolates GG01 and GG04 significantly enhanced dehiscence of ginseng seed by about 81% compared to the untreated control. The candidate's treatment of T. flavus GG01 and GG04 showed the highest decreasing rate of 93% in seed coat hardness for 112 days in dehiscence period. The results suggested that the pre-inoculation of T. flavus GG01 and GG04 found to be very effective applications in improving dehiscence and germination of ginseng seed.

• Journal of the Korea Concrete Institute
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• v.27 no.4
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• pp.343-351
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• 2015

Currently, lots of researches have been performed for reducing cement usages due to increasing social/engineering problems caused by $CO_2$ emission. Supplementary cement materials like fly ash, slag, and silca fume are usually employed for cement replacement, and nowadays rice husk ash (RHA) is widely studied for enhancement of concrete performance as mineral admixture. In this paper, concrete samples with RHA and SF which is known for its engineering advantages are prepared and a resistance to chloride attack is evaluated in early-aged concrete. For the work, replacement ratios of 10~30% for RHA concrete and 2~8% for SF concrete are considered, and various durability tests such as density, void, sorptivity, current measurement, and chloride diffusion coefficient are performed including mechanical test like compressive and tensile strength. Replacement of RHA 10~15% shows better improvement of corrosion resistance and strength than that of SF 2~4% and normal concrete, which shows a strong applicability for utilization as construction materials.