• Journal of the Korean Society of Radiology
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• v.8 no.7
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• pp.389-395
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• 2014

The research was carried out to develop a animal model of malignant brain tumor for the researches in glioblastoma multiform (GBM) diagnosis and therapy. C6 cells were transplanted into the right striatum of SD rat using stereotactic instrument for the development. The developed animal model was verified by MRI and H&E stain assay of anatomicohistological examination. The MRI observations showed that the tumor developed at the injection site at the 7 days after glioblastoma inoculation. At 14 days post inoculation, the tumor grew to a large volume occupying almost a half of the right cerebral hemisphere. It was confirmed that the expression of excessive mitosis and pleomorphism in anatomicohistological examination. The developed animal model must be necessary and useful tool for the in vivo level research in the development of the new modality for the diagnosis and therapy of brain cancer.

• Archives of Reconstructive Microsurgery
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• v.9 no.1
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• pp.62-67
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• 2000

Recently, the incidence of pressure sore has been increased, due to increased number of patients with central nervous system injuries after traffic and industrial accidents or with long term loss of consciousness due to drug intoxication. The management of sacral pressure sore has been improved through the development of myocutaneous flap. However, sacrifice of the deep muscle cause some problems such as intraoperative bleeding, functional disabilities of donor site and further limitation of reconstruction for recurrent pressure sores in paraplegic patients. The development of perforator-based island skin flap introduce a new treatment modality for sacral pressure sores. We used perforator-based island skin flap in 15 cases with reasonable result from January 1998 to February 2000. This flap has a many advantages such as no significant sacrifice of the gluteus maximus muscle, wide rotation arc, reliable blood flow of the perforator, short elevation time for the flap, and no post-operative hindrance to walking in patients who are not paraplegic. There was no significant complication without significant sequelae and donor sites could be repaired primarily.

• Archives of Plastic Surgery
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• v.38 no.3
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• pp.245-250
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• 2011

Purpose: Composite tissue allotransplantation has emerged as a new therapeutic modality to reconstruct major tissue defects of the head, neck and extremities. A questionnaire-based instrument, the Louisville Instrument for Transplantation (LIFT), has been developed to objectively assess the risk-versus-benefit ratio for composite tissue allotransplantation procedures. The objective of this study is to assess if the LIFT is a useful, reliable and valid tool to apply to the Korean population. Methods: Seventy-three medical students and 60 lay public completed the LIFT questionnaire (translated to Korean) over the period from February 2010 to April 2010. Internal consistency was assessed using Cronbach's alpha. Test-retest reliability was analyzed using Pearson's correlation coefficient. Construct validity was assessed by comparing Pearson's correlation coefficients between perceived improvements in quality of life and responses to risk tolerance questions concerning organ transplants. Results: Measurements of the test-retest reliability showed that Pearson's correlation coefficients ranged from 0.241 to 0.902, and Cronbach's alphas ranged from 0.52 to 0.80 for medical students and from 0.63 to 0.83 for the lay public. Pearson's correlation coefficients showed significant correlations between perceived improvements in quality of life and responses to risk tolerance questions concerning organ transplants. Hand transplant showed a significant correlation in medical students. Foot, hand, two hands, larynx, partial face transplants showed significant correlations for the lay public. Conclusion: The applicability of the LIFT to the Korean population was found to be reliable and valid. The LIFT may serve as a useful tool for clinical application in the Korean population.

• Radiation Oncology Journal
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• v.34 no.3
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• pp.230-238
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• 2016

Purpose: Hypoxia can impair the therapeutic efficacy of radiotherapy (RT). Therefore, a new strategy is necessary for enhancing the response to RT. In this study, we investigated whether the combination of nanoparticles and RT is effective in eliminating the radioresistance of hypoxic tumors. Materials and Methods: Gold nanoparticles (GNPs) consisting of a silica core with a gold shell were used. CT26 colon cancer mouse model was developed to study whether the combination of RT and GNPs reduced hypoxia-induced radioresistance. Hypoxia inducible $factor-1{\alpha}$ ($HIF-1{\alpha}$) was used as a hypoxia marker. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining were conducted to evaluate cell death. Results: Hypoxic tumor cells had an impaired response to RT. GNPs combined with RT enhanced anti-tumor effect in hypoxic tumor compared with RT alone. The combination of GNPs and RT decreased tumor cell viability compare to RT alone in vitro. Under hypoxia, tumors treated with GNPs + RT showed a higher response than that shown by tumors treated with RT alone. When a reactive oxygen species (ROS) scavenger was added, the enhanced antitumor effect of GNPs + RT was diminished. Conclusion: In the present study, hypoxic tumors treated with GNPs + RT showed favorable responses, which might be attributable to the ROS production induced by GNPs + RT. Taken together, GNPs combined with RT seems to be potential modality for enhancing the response to RT in hypoxic tumors.

• Journal of Chest Surgery
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• v.26 no.2
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• pp.89-95
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• 1993

30 patients with spontaneous pneumothorax underwent videothoracoscopic treatment between March and July 1992. The patients ranged in age from 16 years to 62 years (mean age, 30.4 years) and the incidence according to age group was highest as 50 % in the adolescence between 21 and 30 years old. The indications of the therapeutic videothoracoscopy for spontaneous pneumothorax were recurrence (30.8％), persistent air leak (30.8％), visible blebs on the chest X-ray (20.4％), tension pneumothorax (15.4％), and bilaterality (2.6％). Intraoperative scopic findings were as follows; blebs (87.1％), pleural adhesion (45.2％), and pleural effusion (22.6％). The operation was performed under general anesthesia with one lung intubation guided by flexible fiberoptic bronchoscopy. Procedures included bleb and/or wedge resection, tetracycline pleurodesis with mechanical abrasion, and parietal pleurectomy. Successful treatment was obtained in 66.7％ (20/30) and the mean postoperative hospital stay of the successful cases was 5 days. Videothoracoscopy also provided the benefits of lesser postoperative pain, rapid recovery, short hospitalization, and smaller scar of wound by reduced trauma on access. The total 13 postoperative complications were occured in 10 patients, which showed somewhat higher rate than that of other reports because of lack of experiences in the earlier period, however, it had decreased progressively as experiences were accumulated and instruments were improved in the later period. The operative mortality was absent. Conclusively, videothoracoscopy is a new interesting modality of surgical treatment of spontaneous pneumothorax and also can be extensively applicable in the diagnosis and treatment of other thoracic surgery.

• Journal of Chest Surgery
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• v.28 no.2
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• pp.156-161
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• 1995

Although there are many kinds of method in treatment of tracheal stenosis, tracheal resection and primary anastomosis can be performed for management of various kinds of tracheal stenosis because it is considered the most anatomical ideal therapeutic modality. During a 10-year period we performed 18 tracheal resection on 18 patients with no operative mortality and some morbidity. 13 patients had tracheal stenosis caused by endotracheal intubation [eight patients or tracheostomy [five patients ; and five patients caused by a variety of neoplastic lesions [four primary and one secondary . The length of tracheal stenosis were various from 1.5cm to 5.5cm and site of tracheal stenosis were cervical[17patients and thoracic [one patient . Operative techniques were tracheal resection and primary anastomosis[18 patients and additional procedures were cricoid cartilage reconstruction with costal cartilage [one patient , primary repair of esophagus[one patient and suprahyoid laryngeal release technique[eight patients without any complications. We have eight complications; tracheal restenosis were developed in five patients[growth of grannulation tissue at anastomotic site in three patients, delayed restenosis in two patients , anastomotic disruption in one patient, hoarseness and pneumonia in each of two patients. We managed tracheal complications with T-tube insertion in two patients, permanent tracheostomy in three patients and insertion of Gianturco tracheal stent in one patient, but tracheal stent did not reveal good result because it caused persistent production of sputum. We concluded that it is necessary to access full length of normal trachea including suprahyoid laryngeal release technique to avoid anastomotic tension in tracheal surgery and develope new ideal techniques to manage postoperative tracheal complications, because we suppose tracheal complications are developed due to anastomotic tension.

• Journal of Science and Technology Studies
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• v.13 no.1
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• pp.181-216
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• 2013

This paper tries to analyze technologies of search engine generally, and reveal the additional modes of Korean search engine at the same time. Recently it said that search engine becomes a self-moving and is getting more strong power than the former one existed. There are many difference interpretative views from technological determination to instrumentalism surrounding this system. Search engine invents the technological mode that draws user's attention to make its own expertise reinforce. It is stemmed from the rationality of its own. Especially Korean search engine exposed unique mutation as self-proliferation of it during past a decade, as for example "related keyword" or "real-time popular keyword" service. Its automatic decision aroused democracy matter, now it is not only web guide. How we do make it to serve in democracy, accepting the independent expertise of it simultaneously? We might find new prospect when focusing on interactional modality between engine and human actor, instead counting both as a separate one.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.5
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• pp.3351-3355
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• 2013

Photodynamic therapy (PDT) is a promising cancer treatment modality that uses dye-sensitized photooxidation of biologic matter in target tissue. This study explored effects of the photosensitizer BCPD-17 during PDT for osteosarcoma. LM-8 osteosarcoma cells were treated with BCPD-17 and cell viability after laser irradiation was assessed in vitro with the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay. The effects of BCPD-17 during PDT recurrence were then examined on tumor-bearing mice in vivo. BCPD-17 had dosedependent cytotoxic effects on LM-8 osteosarcoma cells after laser irradiation which also had energy-dependent effects on the cells. The rate of local recurrence was reduced when marginal resection of mice tumors was followed by BCPD-17-mediated PDT. Our results indicated BCPD-17-mediated PDT in combination with marginal resection of tumors is a potentially new effective treatment for osteosarcoma.

• The Journal of the Korea Contents Association
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• v.16 no.3
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• pp.488-497
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• 2016

Given the potential of mobile applications to create new learning opportunities beyond the prevalent use of digital textbooks and Internet lectures, this study aims to derive types and themes of mobile application content that can be effectively integrated with the school curricula. Twenty primary school teachers participated in this study that examines teachers' perceptions about the advantages and disadvantages of printed and digital textbooks' modality, the advantages and disadvantages of mobile learning, and the themes relevant to develop mobile applications. Findings indicate that it is necessary to develop activity-centered applications for vertical use rather than theme-centered applications for horizontal use. In addition, while most ideas derived from teachers center on multimedia access, there was lack of ideas that leverage the affordances of mobile devices for collaborative interaction and location-awareness. Lastly, to promote the diffusion of mobile learning in school environments, this study suggests the need to overcome teachers' epistemology that perceives mobilization against inquiry activities.

• Journal of Biomedical Engineering Research
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• v.26 no.4
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• pp.223-230
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• 2005

This paper presents a new approach to investigate spatial correlation between independent components of brain alpha activity in functional magnetic resonance imaging (fMRI) and electroencephalography (EEG). To avoid potential problems of simultaneous fMRI and EEG acquisitions in imaging pure alpha activity, data from each modality were acquired separately under a 'three conditions' setup where one of the conditions involved closing eyes and relaxing, thus making it conducive to generation of alpha activity. The other two conditions -- eyes open in a lighted room or engaged in a mental arithmetic task, were designed to attenuate alpha activity. Using a Mixture Density Independent Component Analysis (MD-ICA) that incorporates flexible non-linearity functions into the conventional ICA framework, we could identify the spatiotemporal components of fMRI activations and EEG activities associated with the alpha rhythm. Then, the sources of the individual EEG alpha activity component were localized by a Maximum Entropy (ME) method that is specially designed to find the most probable dipole distribution minimizing the localization error in sense of LMSE. The resulting active dipoles were spatially transformed to 3D MRls of the subject and compared to fMRI alpha activity maps. A good spatial correlation was found in the spatial distribution of alpha sources derived independently from fMRI and EEG, suggesting the proposed method can localize the cortical areas responsible for generating alpha activity successfully in either fMRI or EEG. Finally a functional connectivity analysis was applied to show that alpha activity sources of both modalities were also functionally connected to each other, implying that they are involved in performing a common function: 'the generation of alpha rhythms'.