• Development and Reproduction
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• v.15 no.4
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• pp.273-279
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• 2011

Epigenetic regulation is a phenomenon that changes the gene function without changing the underlying DNA sequences. Epigenetic status of chromosome is regulated by mechanisms such as histone modification, DNA modification, and RNAi silencing. In this review, we focused on histone methylation for epigenetic regulation in ES cells. Two antagonizing multiprotein complexes regulate methylation of histones to guide expression of genes in ES cells. The Polycomb repressive complex 2 (PRC2), including EED, EZH2, and SUZ12 as core factors, contributes to gene repression by increasing trimethylation of H3K27 (H3K27me3). In contrast, the Trithorax group (TrxG) complex including MLL is related to gene activation by making H3K4me3. PRC2 and TrxG accompany a variety of accessory proteins. Most prominent feature of epigenetic regulation in ES cells is a bivalent state in which H3K27me3 and H3K4me3 appear simultaneously. Concerted regulation of PRC2, TrxG complex, and H3K4- or H3K27-specific demethylases activate expression of pluripotency-related genes and suppress development-related genes in ES cells. Modified balance of the regulators also enables ES cells to efficiently differentiate to a variety of cells upon differentiating signals. More detailed insights on the epigenetic regulators and their action will lead us to better understanding and use of ES cells for future application.

• Journal of Life Science
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• v.24 no.2
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• pp.209-217
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• 2014

In a variety of eukaryotic cells, autophagy sequesters a portion of the cytoplasm and targets it to a lytic compartment for degradation in bulk. Autophagy is a dynamic process for degrading cytoplasmic cargoes with various degrees of selectivity, and its activity is tightly regulated in a nutrient- and development-dependent manner. Autophagy research has drawn much attention since autophagy not only is an interesting cell biological phenomenon but also has great potential for medical and agricultural applications. For example, autophagy is associated with cancers and neurodegenerative diseases in human and mammalian cells and is also suggested in remobilization of nutrients during the senescence of plant leaves. In this general review, we describe genetic components of the core autophagic machinery conserved among yeast, animals, and plants and briefly explain how these components are responsible for major steps in plant autophagy. We discuss four common features of autophagic processes: (i) autophagy as a degradation pathway, (ii) the concept of flux in autophagy research, (iii) dependency on developmental and nutritional cues, and (iv) diversity of autophagy, focusing on selective types of autophagy. We also summarize cell biological and physiological functions of plant autophagy. Our intention is to provide a quick guide to autophagy for those who are new to autophagy research.

• Pediatric Infection and Vaccine
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• v.19 no.3
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• pp.141-148
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• 2012

Purpose : Ventriculoperitoneal (VP) shunt insertion is an important treatment modality in children with hydrocephalus. VP shunt infection is a major complication and an important factor that determines the surgery outcome. This 15-year study was performed to evaluate the epidemiology of VP shunt infections in pediatric patients treated at our center. Methods : A retrospective review of medical records was performed in patients 18 years old or younger who underwent VP shunt insertion surgery from April 1995 to June 2010. Results : Three hundred twenty-seven VP shunt surgeries were performed in a total of 190 pediatric patients (83 females, 107 males). The median age of the patients was 2.4 years (range, 0.02-17.9 years). Having a malignant brain tumor was the most frequent cause for VP shunt insertion. The shunt infection rate was 6.7% (22/327) per 100 operations and 9.5% (18/190) per 100 patients, and the incidence rate was 0.45 infection cases per 100 shunt operations-year. The most common pathogen was coagulase-negative staphylococcus (n=7) followed by methicillin resistant Staphylococcus aureus (n=1). Ten cases were treated with vancomycin and beta-lactam antibiotic (cephalosporin or carbapenem) combination therapy and 7 cases were treated with vancomycin monotherapy. The median duration of antibiotic treatment was 26 days (range, 7 to 58 days). Surgical intervention was performed in 18 cases (18/22, 81.8%). Conclusion : Epidemiologic information regarding VP shunt infections in pediatric patients is valuable that will help guide proper antibiotic management. Additional studies on the risk factors for developing VP shunt infections are also warranted.

• Radiation Oncology Journal
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• v.37 no.4
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• pp.265-270
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• 2019

Purpose: Renal cell carcinoma (RCC) and melanoma have been considered 'radioresistant' due to the fact that they do not respond to conventionally fractionated radiation therapy. Stereotactic radiosurgery (SRS) provides high-dose radiation to a defined target volume and a limited number of studies have suggested the potential effectiveness of SRS in radioresistant histologies. We sought to determine the effectiveness of SRS for the treatment of patients with radioresistant brain metastases. Materials and Methods: We performed a retrospective review of our institutional database to identify patients with RCC or melanoma brain metastases treated with SRS. Treatment response were determined in accordance with the Response Evaluation Criteria in Solid Tumors. Results: We identified 53 radioresistant brain metastases (28% RCC and 72% melanoma) treated in 18 patients. The mean target volume and coverage was 6.2 ± 9.5 mL and 95.5% ± 2.9%, respectively. The mean prescription dose was 20 ± 4.9 Gy. Forty lesions (75%) demonstrated a complete/partial response and 13 lesions (24%) with progressive/stable disease. Smaller target volume (p < 0.001), larger SRS dose (p < 0.001), and coverage (p = 0.008) were found to be positive predictors of complete response to SRS. Conclusion: SRS is an effective management option with up to 75% response rate for radioresistant brain metastases. Tumor volume and radiation dose are predictors of response and can be used to guide the decision-making for patients with radioresistant brain metastases.

• Archives of Plastic Surgery
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• v.47 no.5
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• pp.428-434
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• 2020

Background Three-dimensional (3D) model printing improves visualization of anatomical structures in space compared to two-dimensional (2D) data and creates an exact model of the surgical site that can be used for reference during surgery. There is limited evidence on the effects of using 3D models in microsurgical reconstruction on improving clinical outcomes. Methods A retrospective review of patients undergoing reconstructive breast microsurgery procedures from 2017 to 2019 who received computed tomography angiography (CTA) scans only or with 3D models for preoperative surgical planning were performed. Preoperative decision-making to undergo a deep inferior epigastric perforator (DIEP) versus muscle-sparing transverse rectus abdominis myocutaneous (MS-TRAM) flap, as well as whether the decision changed during flap harvest and postoperative complications were tracked based on the preoperative imaging used. In addition, we describe three example cases showing direct application of 3D mold as an accurate model to guide intraoperative dissection in complex microsurgical reconstruction. Results Fifty-eight abdominal-based breast free-flaps performed using conventional CTA were compared with a matched cohort of 58 breast free-flaps performed with 3D model print. There was no flap loss in either group. There was a significant reduction in flap harvest time with use of 3D model (CTA vs. 3D, 117.7±14.2 minutes vs. 109.8±11.6 minutes; P=0.001). In addition, there was no change in preoperative decision on type of flap harvested in all cases in 3D print group (0%), compared with 24.1% change in conventional CTA group. Conclusions Use of 3D print model improves accuracy of preoperative planning and reduces flap harvest time with similar postoperative complications in complex microsurgical reconstruction.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.12
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• pp.5089-5095
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• 2014

Background: As a common and essential contrast medium at present, gadobenate dimeglumine has shown better performance than some other agents when applied to Breast Magnetic Resonance Imaging Screening (Breast MRI Screening). Nevertheless, reports on the diagnostic performance of these two mediums (gadobenate dimeglumine and gadopentetate dimeglumine) are not completely consistent. Objective: To assess the diagnostic value of gadobenate dimeglumine and gadopentetate dimeglumine for Breast MRI Screening in patients suffering from breast cancer and to provide more convinced evidence to guide clinical practice in terms of appropriate contrast agents. Data Sources and Review Methods: Original articles in English and Chinese published before January 2013 were selected from available databases (The Cochrane Library, PUBMED, EMBASE, Chinese Biomedical Literature Database, Chinese Scientific Journals Full-text Database, Chinese Journal Full-text). The criteria for inclusion and exclusion were based on the standard for diagnosis tests. Meta-Disc software (Version 1.4) was used for data analysis. Then, the area under curve (AUC) of SROC and the spearman rank correlation of sensitivity against (1-specificity) were calculated. Results: Total of 17 researches involving 1934 patients were included. The pooled sensitivity of gadobenate dimeglumine and gadopentetate dimeglumine were 0.99 (0.97, 1.00) and 0.93 (0.88, 1.00) respectively. The pooled specificity for these two contrast agents were 0.924 (0.902, 0.943) and 0.838 (0.817, 0.858) respectively, and the AUC of SROC curve were 0.9781 and 0.9215 respectively. Conclusions: Gadobenate dimeglumine can be regarded as a more effective and feasible contrast medium for Breast MRI Screening. At least 5% differences in diagnostic performance are usually considered as clinically relevant.

• Journal of Korean Neurosurgical Society
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• v.48 no.3
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• pp.240-243
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• 2010

Objective : Radiofrequency (RF) medial branch neurotomy is an effective management of lumbar facet syndrome. However, pain may recur after period of time. When pain recurs, it can be repeated, but the successful outcome and duration of relief from repeated procedures are not clearly known. The objective of this study was to determine the success rate and duration of pain relief from repeated radiofrequency medial branch neurotomy for lumbar facet syndrome. Methods : A retrospective review of medical records was done on 60 consecutive patients, from March of 2006 to February of 2009, who had an initial successful RF neurotomy but subsequently underwent repeated procedures due to recurrence of pain. All procedures were done in carefully selected patients after at least two responsive medial branch nerve blocks. C-arm fluoroscopic guide, impedance, sensory and motor threshold monitoring tools were used for the precise placement of electrodes. Responses of repeated procedures were compared with initial radiofrequency neurotomy for success rates and duration of pain relief. Results : There were 48 females and 12 males. Mean age was 52.4 years (range, 26-83). RF medial branch neurotomy was done on one side in 38 and both sides in 22 patients, each covering at least three segments. Average visual analog scale at last procedure was 6.8. Twelve patients had previous lumbar operations, including 4 patients with instrumentations. Fifty-five patients had two procedures and five patients had three procedures. Mean duration of successful pain relief (> 50% of previous pain for at least 3 months period) after initial radiofrequency neurotomy was 10.9 months (range, 3-28) in 51 (85%) patients. From repeated procedures, successful pain relief was seen in 50 (91%) patients with average duration of 10.2 months (range, 3-24). Five patients had third procedure, which was successful in 4 (80%) patients with mean duration of 9.8 months (range, 5-16). This was not statistically different from initial results. There were no permanent neurological complications from the procedures. Conclusion : Results of this study indicate that the frequency of success and durations of relief from repeated RF medial branch neurotomy for lumbar facet syndrome are similar to initial results that provided relatively prolonged period of pain relief without major side effects Each procedure seems to provide successful pain relief for about 10 months in more than 85% of carefully selected patients when properly done.

• Korean Journal of Construction Engineering and Management
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• v.14 no.1
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• pp.133-143
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• 2013

BIM can be utilized variously in construction management(CM) in the respect that it helps to manage comprehensively the construction information and make reliable decisions, but the adoption of BIM is insufficient in the CM area. The purpose of this study is to develop work process models and their guides in order to utilize BIM effectively in CM work at construction stage. This study defined BIM functions as 'BIM converting design', 'Model review', 'Data extraction', 'Automatic estimate', '4D simulation', 'Drawing creation', 'Engineering sector linkage analysis' through literature search, and generated CM works applicable to BIM by analyzing the CM work and process. This study developed BIM-based CM work process models by reconstructing the existing work process in connection with BIM function through an analysis on the relationship between BIM function and CM work, and reconstructing the role of each project participants. In order to improve the usefulness of the developed models, guides that described the BIM works of project participants were prepared through interviews and case studies. To validate the utilization of the models, a comparative analysis on the BIM process of precedent studies was also made and a survey was conducted on experts. This study can contribute to increasing the utilization of BIM in the CM area and can be helpful for CM companies to develop an in-house BIM guide. In the future, it will be necessary to make an assessment on the models from a business perspective through case applications and constantly update BIM-based CM work process model in consideration of the expansion of CM work due to the application of BIM.

• Journal of Korean Public Health Nursing
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• v.9 no.2
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• pp.33-42
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• 1995

The purpose of this study is to identify the smoking patterns and their relevant factors of the public officials who are placed to guide people's way of thinking as conservative middle-income group and thereupon, provide for basic data which can be used to reduce the diseases and death rate caused by smoking in terms of preventive medicine. For this purpose, 170 public officials working for the government agencies located in seoul were surveyed for Jan. 10-Jan. 20, 1995. The results of survey can be analyzed/summarized as follows; 1. In terms of daily smoking frequencies, 50 officials $(29.4\%)$ are driven by stress to smoke. Among these offcials, 250nes $(50.0\%)$ smoke 20-30 times a day. Meanwhile, 22 officials $(12.9\%)$ answered that they smoke for pleasure and comfort, and among them 6 officials $(21.4\%)$ smoke 20-30 times a day. 26 officials $(15.3\%)$ are found to be nicotine­addicted physically or psychologically, and to 10 of them $(35.7\%)$ smoke 20-30 times a day. On the other hand, 10 officials $(5.9\%)$ have habit of smoking and 4 of them $(40.0\%)$ smoke 20-30 times a day. 2. Out of 50 officials $(24.9\%)$ who began smoking on impulse, 44 actually stopped smoking, and the rest 6 officials did not even implement their plan. In view of successful cigarette-stopping, only 8 officials $(15.4\%)$ out of 44 impulse-driven smokers succeeded in stopping cigarettes, while the rest 36 failed all. Meanwhile, out of those 84 officials $(64.6\%)$. Who smoked for reduced stress, 28 ones succeeded, while the rest 56 ones failed. Out of 20 officials who were nicotine-addicted but attempted to stop smoking, only 2 smokers succeeded and the rest 18 were all failures. 3. Factors involving smoking and Their patterns 1) By age group (30's, 40's and 50's), the smoking patterns can be grouped into stress-removing, nocotine-addictive and habitual ones, respectively. 2) By acadeic background, our officials smoke on impulse or due to nocotine addition. 3) The length of career is co-related with nicotine addition. 4) The ownership of house is related with smoking for comfort or less stress. 5) The number of children is related with impulse-driven smoking or smoking for comfort.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.3
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• pp.617-623
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• 2003

The following conclusions are drawn from a review on the theory of correlation between the jang-bu organs in 'Ojangchunchaklon(五臟穿鑿論)' which is quoted in 'Uihakipmoon(醫學入門)' and 'Donguibogam(東醫寶鑑)'. The three yangs and three yins are trisections each of yang ki and y1n ki. They represent three aspects of change in powers of yin ki and yang ki. The theory of Kaehapchu(開闔樞 the opening, closing and pivot) is thought to be the concept which explains the three states of jang-bu organs and meridians in terms of three yangs and three yins. The three yangs and three yins are assigned to twelve months according to the generation, prosperity and vanishment of the water, the fire, the wood and the metal in the circulation of nature with the lapse of time. Most of all, the change of the water and the fire is the main guide to the assignment. Both the theory of exterior-interior relations in jang-bu organs and meridians and the theory of Kaehapchu are founded on the assignment of three yangs and three yins to twelve months. The correlation between jang-bu organs is based on the monthly assignment of three yangs and three yins described in 'Internal classic(內經)' and the theory of Kaehapchu. In the correlations between jang-bu organs and meridians, the exterior-interior relations are the correspondences of Hand to Hand and Foot to Foot. but the relations of Kaehapchu are those of Hand to Foot and Foot to Hand. Jeesan's diagram of pulse is grounded on the correlations between jang-bu organs. On the left of the diagram, jang organs are arranged in the order of hierarchic positions in body. On the right, bu organs are disposed according to the correlations with the jang organs. Jeesan's diagram includes the principles of triple harmony and diagonal groups in twelve earthly branches(十二支). Jeesan's diagram is the frame through which correlations of jung-ki-shin-hyul, five jang and six bu organs, twelve meridians and six intrinsic factors can be observed at once.