• Clinical and Experimental Pediatrics
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• v.46 no.6
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• pp.541-547
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• 2003

Purpose : Gap junction intercellular communication(GJIC) is an important mechanism of the bystander effect in herpes simplex thymidine kinase/ganciclovir(HSVtk/GCV) gene therapy Therefore, we attempted to enhance the bystander effect in vitro by exogenous overexpressing connexin 37(Cx37) in cells to increase GJIC. Methods : NIH3T3 cells were transfected with the Cx37 and HSVtk gene or the HSVtk gene alone by the calcium phosphate method, and we detected their expression from these cells by RT-PCR. GCV-mediated cytotoxicity and the bystander effect of each transfectant was then assessed and compared. Results : Cells transfected with HSVtk became sensitive to low concentration of GCV. We found significantly increased cytotoxicity in HSVtk/GCV gene therapy after introduction of the HSVtk and Cx37 genes together compared with the cytotoxicity seen after introduction of the HSVtk gene in vitro. Co-expression of the HSVtk and Cx37 genes potentiates HSVtk/GCV gene therapy through the bystander effect. Conclusion : These results indicated that the increase of GJIC using Cx37 have potentiated the bystander effect of HSVtk/GCV therapy, and may be a new approach to improve response in suicidal cancer gene therapy.

• Clinical and Experimental Pediatrics
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• v.52 no.2
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• pp.213-219
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• 2009

Purpose:Iron is a critical nutritional element that is essential for a variety of important biological processes, including cell growth and differentiation, electron transfer reactions, and oxygen transport, activation, and detoxification. Iron is also required for neoplastic cell growth due to its catalytic effects on the formation of hydroxyl radicals, suppression of host defense cell activities, and promotion of cancer cell multiplication. Chronic transfusion-dependent patients receiving chemotherapy may have iron overload, which requires iron-chelating therapy. We performed this study to demonstrate whether the iron chelating agent deferoxamine induces apoptosis in Saos-2 osteosarcoma cells, and to investigate the underlying apoptotic mechanism. Methods:To analyze the apoptotic effects of an iron chelator, cultured Saos-2 cells were treated with deferoxamine. We analyzed cell survival by trypan blue and crystal violet analysis, apoptosis by nuclear condensation, DNA fragmentation, and cell cycle analysis, and the expression of apoptotic related proteins by Western immunoblot analysis. Results:Deferoxamine inhibited the growth of Saos-2 cell in a time- and dose-dependent manner. The major mechanism for growth inhibition with the deferoxamine treatment was by the induction of apoptosis, which was supported by nuclear staining, DNA fragmentation analysis, and flow cytometric analysis. Furthermore, bcl-2 expression decreased, while bax, caspase-3, caspase-9, and PARP expression increased in Saos-2 cells treated with deferoxamine. Conclusion:These results demonstrated that the iron chelating agent deferoxamine induced growth inhibition and mitochondrial-dependent apoptosis in osteosarcoma Saos-2 cells, suggesting that iron chelating agents used in controlling neoplastic cell fate can be potentially developed as an adjuvant agent enhancing the anti-tumor effect for the treatment of osteosarcoma.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.2
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• pp.82-94
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• 2014

This study aims to comprehend that Gwanghalluwon for aspects of landscape change in terms of construction garden(樓園). Transformation focused on the spatial structure is divided into four periods based on literature. And reflect of landscape elements in defunct or unattributable records from tale and novel. The results were as follows. First, The beginning of Gwanghanllu pavilion(廣寒樓) was the composition of the Gwangtongnu Pavilion(廣通樓). The pavilion is located amid beautiful scenery such as the close-range view of a small stream, and distant view Jiri Mountain. Analysis of literature shows that Gwanghallu pavilion was in succession to Gwangtongnu Pavilion's landscape. Secondly, Gwanghallu(廣寒樓) pavilion represents the characteristic of the garden since 1582. Built the Samsinsan(三神山), Construct Lake and bridge that represents the galaxy for realization of utopia reflect in Taoist ideology. Thirdly, Gwanghalluwon garden was recovered when from Jeong-yu-jae-ran(丁酉再亂) to the Japanese Ruling Era. It took Gwanghalluwon garden a long while to recover from original form. According to records, Gwanghalluwon garden is still being likened to the landscape of fairyland by inheriting landscape in the previous of Jeong-yu-jae-ran(丁酉再亂). Fourth, By the modern times, Gwanghalluwon Garden has personality of tourist attractions. Until now, the area of the Gwanghalluwon garden has been expended during the processes of three times. Fifth, Aspect of landscape change of Gwanghalluwon is wide-spreading mainly Gwanghallu pavilion. But elements of external expansion in garden by introduced into the facility irrelevant to the authenticity of the garden. Sixth, Comprehension the cultural landscape of the garden are limited by deficient records. But, the main elements in the Gwanghalluwon garden are commonly appeared on imaginary environment within a tale and a novel. In addition, culture of garden at the time was depicted in tale and novel. In this sense, cultural landscape in garden was able to estimate through imaginary environment within novel.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.12 no.1
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• pp.25-50
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• 2001

Using Fourier transformation and wavelet analysis, we compared the auditory event-related potentials of the patients with attention deficit-hyperactivity disorders(abbr. ADHD, 13 boys) and normal control children(8 boys). Amplitudes of the event-related potentials which were calculated via Fourier transformation were compared between the groups and between conditions(non-target versus target) in each group. To the non-target stimuli, the patients with ADHD showed significantly greater amplitudes across almost all of the electrode sites and frequencies. To the target stimuli, the incidents which ADHD patients showed much higher amplitudes than normal controls significantly decreased, while those of the reverse results increased significantly. These results were consistent with the comparison results about negative difference wave(abbr. Nd wave) using Fourier transformation. In summary, it was proved that non-target stimulus which should be ignored elicited more robust electrical response from the patients with ADHD than normal children, but the target stimulus which reguired active processing did much less electrical activity in the patients. For the patients, they showed much inhibited electrical response to the target stimuli in some electrodes and frequency ranges. Normal children were more strongly stimulated by the target stimuli in almost all electrodes and frequency ranges than the patients, but less in prefrontal leads and frontal leads. Wavelet analysis results proved that early responses(0-300msec) to the nontarget stimuli of the patients were significantly greater than the normal controls in prefrontal, anterior frontal, some parts of temporal, and occipital lobes and that late response(300-370msec) were significantly lesser than normal children in parietal and central electrodes. Target stimuli elicited significantly higher electrical activity in both group than non-target stimuli did. Prefrontal and frontal lobes showed stronger responses in the patients than normal children irrespective of stimulus condition, but parietal and temporal lobes did higher activities in normal children than the patients only to the target stimuli. In conclusion, the patients with ADHD showed much greater responses to the stimuli which should be ignored, but failed to activated the necessary processes to the target stimuli. Also, we found that the frequency-dimension analysis and wavelet analysis were useful for the signal processing such as event related potentials.

• Journal of the Society of Disaster Information
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• v.10 no.4
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• pp.518-527
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• 2014

Our society is changed and diversified rapidly and such tendency is accelerated day after day and has made a lot of problems in the many fields. The important thing we have to recognize is such tendency has a bad effect recently on the safety system in Korea. So it is time to enhance the national safety system and moreover recently Sewol-ho(passenger ship) went down in the sea, it made people remind the importance of national safety system. With this incident, Korean government decided to establish the national safety communication network against the disaster. At this time, I will propose several ideas about the national safety communication network. 1. It must to be established an unified network to contact people who is on a disaster site anytime and anywhere. This is most important element on all disaster sites. 2. PS-LTE technology must to be adopted to the network because it has many advantages including various multimedia services compared to the TETRA in the past. 3. 700MHz is the most efficient band for the network because it has wide cell sites coverage compared to 1.8GHz. 4. Satellite communication system is needed to the network for back-up. 5. It will be effective to adopt Social Media to the communication network system like a Twitter or Facebook for sharing many kinds of information and notifying people of warning message. 6. It can make the network more useful to introduce the latest technology like a sensor network. And Korean government has to improve the system related to the disaster including law and operating organization.

• Korean Journal of Ecology and Environment
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• v.38 no.4 s.114
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• pp.482-493
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• 2005

The objective of this research was to evaluate an sampling effect of fish species and individual number on sampling techniques of electrofishing and conventional capture methods of cast net and kick net in 38 stream sites sampled during June - September, 2005. For the study, sampling gears were categorized as three types of electrofishing method (EM), conventional sampling technique (CM), and the combined technique (CT) of the electrofishing and the conventional method to compare statistical differences. Major differences of species composition between the CM and EM method were found in some benthic species of Misgurnus mizolepis and Iksookimia koreensis along with lithophilic species of Pungtungia herzi. These species were predominated in the EM rather than the CM, indicating that conventional sampling can underestimate the abundance of benthic or lithophilic species. In contrast ,individual number of typical water column species such as Zacco platypus and Zacco temmincki were more sampled by the CM, so that these fish populations were community overestimated. Also, t-tests on the types of sampling gear from various watersheds of Chogang Stream, Yugu Stream, Daejeon Stream, and Gap Stream showed that total individual numbers and species number in each stream were significantly (t values = 2.806-6.896, p values<0.05, n = 5-14) greater in the CT than the CM. Similar statistical significance (p<1.001, n = (10-24) on sampling seasons were observed during the monsoon and postmonsoon. These results indicate that if the electrofishing is not added to the conventional gears, the abundance of fish population and community can be underestimated and some benthic or lithophilic species may be excluded from the analysis, resulting in overall errors including sampling, fish fauna, and final judgement of community abundance. Overall our results strongly suggest that new application of electrofishing method along with the conventional sampling gears reduce sampling bias on underestimation of the real fish populations and communities.

• Childhood Kidney Diseases
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• v.11 no.1
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• pp.74-82
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• 2007

Purpose : To analyze the clinical characteristics, spontaneous resolution rate and predictive factors of resolution in children with primary vesicoureteral reflux(VUR). Methods : Between October 1991 and July 2003, 149 children diagnosed with primary VUR at Chonbuk National University Hospital were reviewed retrospectively. All of the patients were maintained on low-dose antibiotic prophylaxis and underwent radionuclide cystograms at 1 year intervals over 3 years after the initial diagnosis of VUR by voiding cystourethrogram was made. Results : The median time to resolution of VUR was 24 months and the total 3 year-cumulative resolution rate of VUR was 61.7%. The following variables were associated with resolution of VUR according to univariate analysis-; age<1 year, male gender, mild grade of reflux, unilateral reflux, congenital hydronephrosis as clinical presentation at time of diagnosis of VUR, absence of focal defects in the renal scan at diagnosis, absence of recurrent UTI, renal scars and small kidney during follow-up. After adjustment by Cox regression model, five variables remained as independent predictors of VUR resolution; age<1 yew, relative risk 1.77(P<0.05), VUR grade I+II 2.98(P<0.05), absence of renal scars 2.23(P<0.05), and absence of small kidney 5.20(P<0.01) during follow-up. Conclusion : In this study, spontaneous resolution rate of VUR, even high grade reflux, is high in infants during medical management, and it was related to age, reflux grade at diagnosis, absence of renal scars and small kidney during follow-up. Therefore early surgical intervention should be avoided and reserved for the selected groups.

• Childhood Kidney Diseases
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• v.11 no.1
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• pp.65-73
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• 2007

Purpose : Voiding cystourethrography(VCUG) is a commonly performed diagnostic procedure in children with urinary tract infections. Recently, with the widespread use of prenatal ultrasonography, VCUG is performed as part of the postnatal radiological evaluation of asymptomatic infants with prenatally detected hydronephrosis. The procedure is relatively simple but it involves discomfort and some complications. We studied post procedural symptoms and complications in children who underwent VCUG. Methods : This study reviewed 259 patients who underwent VCUG in our hospital between October 2005 and September 2006. We did a chart review and a telephone interview with the patients' parents about symptoms and complications associated with VCUG. Results : Among 269 children, 217 patients(80.7%) were under 2 years of age and 5 patients (1.9%) were over 8 years of age. Their mean age was $13.1{\pm}22.9$ months. After VCUG, dysuria was found in 49 patients presented with dysuria, and irritability in 36 patients with irritability. Other complications were hematuria, fever, frequency, bladder rupture and urinary tract infection. Mean symptoms duration was $1.4{\pm}0.7$ days. There was no significant relationship between prophylactic antibiotics use and complication rate associated with VCUG. Conclusion : Our study demonstrated that 32.7% of patients showed complications including bladder rupture and urinary tract infection after VCUG. We also found that prophylactic antibiotics use did not prevent urinary tract infection nor decrease the rate of complications associated with VCUG. Therefore, we suggest that the procedure must be done carefully and aseptically, and we should closely observe the children who undergo VCUG for development of possible complications.

• Investigative Magnetic Resonance Imaging
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• v.14 no.1
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• pp.31-40
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• 2010

Purpose : To compare the relative values of various fast breath-hold imaging sequences for superparamagnetic iron-oxide (SPIO)-enhanced hepatic MRI for the assessment of solid focal lesions with a 3T MRI unit. Materials and Methods : 102 consecutive patients with one or more solid malignant hepatic lesions were evaluated by spoiled gradient echo (GRE) sequences with three different echo times (2.4 msec [GRE_2.4], 5.8 msec [GRE_5.8], and 10 msec [GRE_10]) for $T2^*$-weighted imaging in addition to T2-weighted turbo spin echo (TSE) sequence following intravenous SPIO injection. Image qualities of the hepatic contour, vascular landmarks and artifacts were rated by two independent readers using a four-point scale. For quantitative analysis, contrast-to-noise ratio (CNR) was measured in 170 solid focal lesions larger than 1 cm (107 hepatocellular carcinomas, nine cholangiocarcinomas and 54 metastases). Results : GRE_5.8 showed the highest mean points for hepatic contour, vascular anatomy and imaging artifact presence among all of the subjected sequences (p<0.001) and was comparable (p=0.414) with GRE_10 with regard to lesion conspicuity. The mean CNRs were significantly higher (p<0.001) in the following order: GRE_10 ($24.4{\pm}14.5$), GRE_5.8 ($14.8{\pm}9.4$), TSE ($9.7{\pm}6.3$), and GRE_2.4 ($7.9{\pm}6.4$). The mean CNRs of CCCs and metastases were higher than those of HCCs for all imaging sequences (p<0.05). Conclusion : Regarding overall performances, GRE using a moderate echo time of 5.8 msec can provide the most reliable data among the various fast breath-hold SPIO-enhanced hepatic MRI sequences at 3T unit despite the lower CNR of GRE_5.8 compared to that of GRE_10.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.3
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• pp.82-95
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• 2014

This study aims to draw up measures to planting tree and maintain a landscape in traditional space. Preceding comprehensive theoretical consideration of selected species of trees and tree maintenance. And analysis of present condition of planting in cases of Gwanghalluwon Garden, then draw a maintenance plans of planting through species of trees and landscape of planting recorded in literature. The results were as follows. First, Analysis of selected species of trees and tree maintenance that traditional space. A dispute about the selection species of trees in traditional space has been continued until today. Because unconditional reject of foreign trees are limited. In this context, should be sublated that hasty blind faith of records and dichotomous preparation plans such as removal of foreign trees and implicitly planting of native plants. Secondly, Planted trees in Gwanghalluwon garden was investigated and found to the species of trees used in traditional space such as Pine(Pinus densiflora S. et Z.), Sawleaf Zelkova(Zelkova serrata), Ginkgo(Ginkgo biloba), Crape Myrtle(Lagerstroemia indica L.). But, present planting irrelevant to traditional space, except Gwanghallu pavilion area from the spatiality. Thirdly, A look at the records or literature that maintenance of planting through historical research are limited. Because literature was recorded Salix spp., Crape Myrtle, Bambusoideae(Pseudosasa japonica), lotus only among planted trees in Gwanghalluwon garden. Fourth, Gwanghallu zone have nature of history and sense of place. And It was going to restore the appearance on historical. Consequently maintenance plan of planting of Gwanghallu zone should be maintain the current state. Wanwol pavillion zone can be recognized as the original form because they look similar to the Gwangallu zone's buildings. Therefore, it is necessary to secure the sense of place different from Gwanghallu zone by buffer planting for composition of transition space. Wolmaejip zone and lawn zone was marketplace in outside of castle and large forest. Accordingly, this area should be symbolic restoration of the Yulrim(栗林) and representation of the marketplace in outside of castle through aggregation of facilities and administrative facilities in Gwanghalluwon garden. East lawn of the Wanwol pavilion zone is should be maintained the current state that opened place in terms of using thought linked with the Wanwol pavilion zone. Boundary zone of the Gwanghalluwon garden is difficult to associate in terms of historical research and authenticity. Therefore, application of cultural landscape that appeared in literature is be worth.