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Spatio-temporal Variations in the Dynamics and Export of Large Wood in Korean Mountain Streams (우리나라 산지계류에 있어서 유목 동태의 시.공간적 다양성과 그에 따른 유출 특성)

  • Seo, Jung Il;Chun, Kun Woo;Kim, Suk Woo;Im, Sangjun
    • Journal of Korean Society of Forest Science
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    • v.101 no.3
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    • pp.333-343
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    • 2012
  • In-stream large wood (LW) has a critical impact on the geomorphic characteristics relevant to ecosystem management and disaster prevention, yet relatively little is known about variations in its dynamics and subsequent export on the watershed-scale perspective in Korea. Here we review variations in the dynamics and subsequent export of LW as a function of stream size, which is appropriate for Korean mountain streams. In upstream channels with narrow bankfull widths and low stream discharges, a massive amount of LW, resulting from forest dynamics and hillslope processes, may persist for several decades on valley floor. These pieces, however, are eventually transported during infrequent debris flows from small tributaries, as well as peak hydrology in main-stem channels. During the transport, these pieces suffer fragmentation caused by frictions with boulders, and stream bank and bed. Although infrequent, these events can be dominant processes in the export of significant amounts of LW from upstream channel networks. In downstream channels with wide bankfull widths and high stream discharges, LW is dominantly recruited by forest dynamics and bank erosion only at locations where the channel is adjacent to mature riparian forests. With the LW pieces that are supplied from the upstream, these pieces are continuously transported downstream during rainfall events. This leads to further fragmentation of the LW pieces, which increases their transportability. With decreasing stream-bed slope, these floated LW pieces, however, can be stored and form logjams at various depositional sites, which were developed by interaction between channel forms and floodplains. These pieces may decay for decades and be subsequently transported as particulate or dissolved organic materials, resulting in the limitation of LW fluvial export from the systems. However, in Korea, such depositional sites were developed in the extremely limited streams with a large dimension and no flood history for decades, and thus it does not be expected that the reduction of LW export amount, which can be caused by the long-term storage. Our review presents a generalized view of LW processing and is relevant to ecosystem management and disaster prevention for Korean mountain streams.

Identification of Interleukin 1-Responsive Genes in Human Chondrosarcoma SW1354 cells by cDNA Microarray Technology

  • Jeon, Jun-Ha;Jung, Yong-Wook;Yun, Dae-Young;Kim, Hyun-Do;Kwon, Chang-Mo;Hong, Young-Hoon;Kim, Jae-Ryong;Lee, Choong-Ki
    • Journal of Yeungnam Medical Science
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    • v.24 no.1
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    • pp.24-40
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    • 2007
  • Background : Accumulating evidence shows that interleukin(IL)-1 plays a critical role in inflammation and connective tissue destruction observed in both osteoarthritis and rheumatoid arthritis. IL-1 induces gene expression related to cytokines, chemokines and matrix metalloproteinases by activation of many different transcription factors. Materials and Methods : The chondrosarcoma cell line, SW1353, is known to be a valuable in vitro system for investigating catabolic gene regulation by IL-$1{\beta}$ in chondrocytic cells. To explore and analyze the changes in gene expression by IL-1 responsible for arthritis, SW1353 was treated with IL-1 for 1, 6 and 24 h and then total RNAs were purified for each time. The changes in gene expression were analyzed with 17k human cDNA microarrays and validated by semi-quantitative RT-PCR. Results : Greater than a two-fold change was observed in 1,200 genes including metallothioneins, matrix metalloproteinases, extracellular matrix proteins, antioxidant proteins, cytoskeleton proteins, cell cycle regulatory proteins, proteins for cell growth and apoptosis, signaling proteins and transcription factors. These changes appeared to be correlate with the pathophysiological changes observed in early osteoarthritis. Conclusion : cDNA microarray analysis revealed a marked variability in gene expression, and provided insight into the overall molecular changes. The result of this study provide initial information for further studies to identify therapeutic targets in osteoarthritis pathogenesis.

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Microarray Analysis of Long Non-coding RNA Expression Profile Associated with 5-Fluorouracil-Based Chemoradiation Resistance in Colorectal Cancer Cells

  • Xiong, Wei;Jiang, Yong-Xin;Ai, Yi-Qin;Liu, Shan;Wu, Xing-Rao;Cui, Jian-Guo;Qin, Ji-Yong;Liu, Yan;Xia, Yao-Xiong;Ju, Yun-He;He, Wen-Jie;Wang, Yong;Li, Yun-Fen;Hou, Yu;Wang, Li;Li, Wen-Hui
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.8
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    • pp.3395-3402
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    • 2015
  • Background: Preoperative 5-fluorouracil (5-FU)-based chemoradiotherapy is a standard treatment for locally advanced colorectal cancer (CRC). However, CRC cells often develop chemoradiation resistance (CRR). Recent studies have shown that long non-coding RNA (lncRNA) plays critical roles in a myriad of biological processes and human diseases, as well as chemotherapy resistance. Since the roles of lncRNAs in 5-FU-based CRR in human CRC cells remain unknown, they were investigated in this study. Materials and Methods: A 5-FU-based concurrent CRR cell model was established using human CRC cell line HCT116. Microarray expression profiling of lncRNAs and mRNAs was undertaken in parental HCT116 and 5-FU-based CRR cell lines. Results: In total, 2,662 differentially expressed lncRNAs and 2,398 mRNAs were identified in 5-FU-based CRR HCT116 cells when compared with those in parental HCT116. Moreover, 6 lncRNAs and 6 mRNAs found to be differentially expressed were validated by quantitative real time PCR (qRT-PCR). Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis for the differentially expressed mRNAs indicated involvement of many, such as Jak-STAT, PI3K-Akt and NF-kappa B signaling pathways. To better understand the molecular basis of 5-FU-based CRR in CRC cells, correlated expression networks were constructed based on 8 intergenic lncRNAs and their nearby coding genes. Conclusions: Changes in lncRNA expression are involved in 5-FU-based CRR in CRC cells. These findings may provide novel insight for the prognosis and prediction of response to therapy in CRC patients.

Gametogenesis and Reproductive Cycle of the Cockle, Fulvia mutica (Reeve) (새조개, Fulvia mutica (Reeve)의 생식세포형성과정 및 생식주기)

  • CHANG Young Jin;LEE Taek Yuil
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.15 no.3
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    • pp.241-250
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    • 1982
  • The structure of gonads, gametogenesis and reproductive cycle of the cockle, Fulvia mutice, were studied mainly by histological observation. The materials were monthly sampled in the southern area of Yeosu from October 1980 to September 1981. F. mutica was monoecious. The gonads were situated between the liver tissues and the outer fibronuscular layers compacted by the connective tissue fibers and muscle fibers beneath the outermost layer of simple cuboidal epithelium. The gonad was composed of a number of the ovarian sacs and the testicular tubules which form the tubular structure. Testicular tubules in the mature stage sometimes contained 'testis-ova' The undifferentiated mesenchymal tissues and the eosinophilic cells were abundantly distributed on the germinal epithelium in the early development stage. With the further development of the ovary and testis, these tissues and cells gradually disapprared. The undifferentiated mesenchymal tissues and the eosinophilic cells are related to the growing of the oocytes and spermatocytes . Early multiplicating oogonium was about $10{\mu}m$ in diameter. As the oocytes grow to $27-34\times50-58{\mu}m$ by increasing cytoplasm, the oocytes connected to the basement membrane by their egg-stalks. The ripe eggs were about $60{\mu}m$ in diameter and they were surrounded by gelatinous membrane. Most male germ cells in mature stage were transformed into the spermatozoa and they formed the sperm bundles. After spawning, undischarged ripe eggs and spermatozoa remained in the ovarian sac and the testicular tubule respectively for some time, then they finally degenerated. Especially the early spent ovarian sacs in May did not contract significantly and then they took part in the secondary maturation within two or three months during the summer season. The monthly changes of the fatness well agreed with the reproductive cycle. The reproductive cycle of F. mutica could be classified into six successive stages : multiplicative, growing, mature, spent, degenerative and recovery stage. It seems that the spawning season is closely rotated to the water temperature, and the spawning occurs from May to October at about $20^{\circ}C$ in water temperature. The peak spawning seasons appeared twice a year between June and July and in September. Acknowledgement The authors wish to express their gratitude to Dr. Kim, In Bae, Dr. Chun, Seh Kyu and Dr. Yoo, Sung Kyoo of National Fisheries University of Busan and Mr. Min, Byoung Seo of National fisheries Research and Development Agency for their critical reading of the manu script.

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Radiation Oncology Digital Image Chart 8nd Digital Radiotherapv Record System at Samsung Medical Center (디지털 화상 병력 시스템과 디지털 방사선치료 기록 시스템의 개발과 사용 경험)

  • Huh Seung Jae;Ahn Yong Chan;Lim Do Hoon;Cho Chung Keun;Kim Dae Yong;Yeo Inhwan;Kim Moon Kyung;Chang Seung Hee;Park Suk Won
    • Radiation Oncology Journal
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    • v.18 no.1
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    • pp.67-72
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    • 2000
  • Background :The authors have developed a Digital image chart(DIC) and digital Radiotherapy Record System (DRRS). We have evaluated the DIC and DRRS for reliability, usefulness, ease of use, and efficiency. Materials and Methods :The basic design of the DIC and DRRS was to build an digital image database of radiation therapy Patient records for a more efficient and timely flow of critical image information throughout the department. This system is a submit of comprehensive radiation oncology management system (C-ROMS) and composed of a picture archiving and communication system (PACS), a radiotherapy information database, and a radiotherapy imaging database. The DIC and DRRS were programmed using Delphi under a Windows 95 environment and is capable of displaying the digital images of patients identification photos, simulation films, radiotherapy setup, diagnostic radiology images, gross lesion Photos, and radiotherapy Planning isodose charts with beam arrangements. Twenty-three clients in the department are connected by Ethernet (10 Mbps) to the central image server (Sun Ultra-sparc 1 workstation). Results :From the introduction of this system in February 1998 through December 1999, we have accumulated a total of 15,732 individual images for 2,556 patients. We can organize radiation therapy in a 'paperless' environment in 120 patients with breast cancer. Using this system, we have succeeded in the prompt, accurate, and simultaneous access to patient care information from multiple locations throughout the department. This coordination has resulted in improved operational efficiency within the department. Conclusion :The authors believe that the DIC and DRRS has contributed to the improvement of radiation oncology department efficacy as well as to time and resource savings by providing necessary visual information throughout the department conveniently and simultaneously. As a result, we can also achieve the 'paperless' and 'filmless' practice of radiation oncology with this system.

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Analysis of Prognostic Factors in Patients with Carcinoma of Uterine Cervix (자궁경부암의 방사선치료시 예후인자의 재분석)

  • Kim Jae Young;Cho Chul Koo;Shim Jae Won;Yoo Seong Yul;Kim Mi Sook;Yun Hyong Geun
    • Radiation Oncology Journal
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    • v.14 no.4
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    • pp.307-315
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    • 1996
  • Purpose : The authors conducted a retrospective analysis of patients with the carcinoma of uterine cervix treated with curative radiation therapy to evaluate the prognostic factors that would affect the results of the therapy and to get the critical ideas in determining more aggressive treatment schedule. Methods and Materials : From January 1987 to December 1988. Four hundreds and sixty patients with uterine cervical carcinomas treated with radiotherapy at KCCH were registered to this retrospective study. One hundred and three patients were treated with external radiation therapy alone, and 357 patients were treated with external radiation followed by low dose rate intracavitary radiation therapy. The follow-up rate was 88% and median follow-up duration was 48 months. Results : The overall 5 year survival rate of the patients was 67.7%, and when classified by FIGO stages, 5 year survival rates were 81.2%, 76.3%, 73.1%, 50%. 52.3%, 11.5% for stages Ib, IIa, IIb, IIIa, IVa respectively. Tumor size(p=0.0002), endocervical growth pattern(p=0.003), lymph node invasion(p=0.0001), mean hemoglobin level(p=0.0001), and pathologic cell type(p=0.0001) were significant prognostic factors and decrease in survival for young age patient group was marginally important (p=0.03). Conclusion : Significant prognostic factors in the radiation therapy of the uterine cervical carcinoma were tumor size, growth pattern of tumor, lymph node invasion, pathologic cell type, hemoglobin level of patients during treatment and lower survival rate in young age group was obvious, too. Patients with large size tumor(${\geq)$4cm), especially combined with endocervical growth patterns or advanced stages(III or more) need more aggressive treatment to improve the outcome of treatment. And positive feature of lymph node invasion affected the result of therapy, so improvement in the diagnostic and therapeutic trial is essential.

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Study on the Photoneutrons Produced in 15 MV Medical Linear Accelerators : Comparison of Three-Dimensional Conformal Radiotherapy and Intensity-Modulated Radiotherapy (15 MV 의료용 선형가속기에서 발생되는 광중성자의 선량 평가 - 3차원입체조형방사선치료와 세기조절방사선치료의 비교 -)

  • Yang, Oh-Nam;Lim, Cheong-Hwan
    • Journal of radiological science and technology
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    • v.35 no.4
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    • pp.335-343
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    • 2012
  • Intensity-modulated radiotherapy(IMRT) have the ability to provide better dose conformity and sparing of critical normal tissues than three-dimensional radiotherapy(3DCRT). Especially, with the benefit of health insurance in 2011, its use now increasingly in many modern radiotherapy departments. Also the use of linear accelerator with high-energy photon beams over 10 MV is increasing. As is well known, these linacs have the capacity to produce photonueutrons due to photonuclear reactions in materials with a large atomic number such as the target, flattening filters, collimators, and multi-leaf collimators(MLC). MLC-based IMRT treatments increase the monitor units and the probability of production of photoneutrons from photon-induced nuclear reactions. The purpose of this study is to quantitatively evaluate the dose of photoneutrons produced from 3DCRT and IMRT technique for Rando phantom in cervical cancer. We performed the treatment plans with 3DCRT and IMRT technique using Rando phantom for treatment of cervical cancer. An Rando phantom placed on the couch in the supine position was irradiated using 15 MV photon beams. Optically stimulated luminescence dosimeters(OSLD) were attached to 4 different locations (abdomen, chest, head and neck, eyes) and from center of field size and measured 5 times each of locations. Measured neutron dose from IMRT technique increased by 9.0, 8.6, 8.8, and 14 times than 3DCRT technique for abdomen, chest, head and neck, and eyes, respectively. When using IMRT with 15 MV photonbeams, the photoneutrons contributed a significant portion on out-of-field. It is difficult to prevent high energy photon beams to produce the phtoneutrons due to physical properties, if necessary, It is difficult to prevent high energy photon beams to produce the phtoneutrons due to physical properties, if necessary, it is need to provide the additional safe shielding on a linear accelerator and should therefore reduce the out-of-field dose.

Monitoring Bacillus cereus and Aerobic Bacteria in Raw Infant Formula and Microbial Quality Control during Manufacturing (영.유아용 식품원료의 Bacillus cereus와 일반세균 모니터링 및 제조공정 중 미생물 품질제어)

  • Jung, Woo-Young;Eom, Joon-Ho;Kim, Byeong-Jo;Ju, In-Sun;Kim, Chang-Soo;Kim, Mi-Ra;Byun, Jung-A;Park, You-Gyoung;Son, Sang-Hyuck;Lee, Eun-Mi;Jung, Rae-Seok;Na, Mi-Ae;Yuk, Dong-Yeon;Gang, Ji-Yeon;Heo, Ok-Sun;Yoon, Min-Ho
    • Korean Journal of Food Science and Technology
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    • v.42 no.4
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    • pp.494-501
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    • 2010
  • The purpose of this study was to examine the presence of Bacillus cereus, aerobic bacteria and coliforms in the raw material of infant formulas and investigate the manufacturing process in terms of microbial safety. Among ten kinds of raw infant formula material samples (n=20), Bacillus cereus appeared in two (n=4). Aerobic bacteria were not detected in raw infant formula material or maximum 4.15 log CFU/g. Eleven species of aerobic bacteria were isolated and 76% of them were Sphingomonas paucimobilis, Pseudomonas fluorescens, Rhizobium radiobactor, or Stenotrophomonas maltophilia. A Pearson's correlation analysis revealed that the most influential factors for detecting Bacillus cereus were aerobic bacteria and coliforms. In other words, when the measured values of aerobic bacteria and coliforms were higher, the possibility that Bacillus cereus would appear increased. In a regression model to predict Bacillus cereus, the rate of appearance was correlated with aerobic bacteria and coliforms, and its contribution rate for effectiveness was 86%. Improving microbial quality control by pasteurization, spray dry, popping and extrusion resulted in a decrease in the numbers of Bacillus cereus, aerobic bacteria and coliforms in the raw materials. The results suggest that a hazard analysis and critical control point system might be effective for reducing microbiological contamination.

Clinical Application of 3-D Conformal Radiotherapy for Carcinoma of the Ethmoid Sinus : I. Comparative Analysis Between Conventional 2-D and 3-D Conformal Plans (사골동 종양의 3-차원 입체조형치료 : I. 2차원 치료계획과 3차원 치료계획의 비교분석)

  • Lee Sangwook;Kim Gwi Eon;Keum Ki Chang;Park Hee Chul;Cho Jae Ho;Han Soung Uk;Lee Kang Kyu;Suh Chang Ok;Hong Won Pyo;Park In Yong
    • Radiation Oncology Journal
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    • v.15 no.4
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    • pp.287-296
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    • 1997
  • Purpose : This is study of whether 3-D conformal radiotherapy for carcino-mas of the ethmoid sinus were better than those treated with conventional 2-D plan, Materials and Methods : The 3-D conformal treatment Plans were compared with conventional 2-D plans in 4 patients with malignancy of the ethmoid sinus. Isodose distribution, dose statistics, and dose volume histogram of the planning target volume were used to evaluate differences between 2-D and 3-D plans. In addition. the risk of radiation exposure of surrounding normal critical organs are evaluated by means of point dose calculation and dose volume histogram. Results : 3-D conformal treatment plans for each patient that the better tumor coverages by the planning target volume with improved dose homo-geneity, compared to 2-D conventional treatment Plans in the same Patient. On the other hand, the radiation dose distributions to the surrounding nor-mal tissue organs, such as the orbit and optic nerves are not significantly reduced with our technique, but a substantial sparing in the brain stem and optic chiasm for each patient. Conclusion : Our findings represented the potential advantage of 3-D treatment planning for dose homogeniety as well as sparing of the normal tissue surrounding the tumor. However, further investigational studies are required to define the clinical benefit.

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Development of Immobilization Devices for Patients with Pelvic Malignancies and a Feasibility Evaluation during Radiotherapy (골반부 암 환자를 위한 고정기구 개발 및 방사선치료 시 효용성 평가)

  • Park, Jong-Min;Park, Yang-Kyun;Cho, Woong;Park, Charn-Il;Ha, Sung-Whan
    • Radiation Oncology Journal
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    • v.25 no.2
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    • pp.134-144
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    • 2007
  • [ $\underline{Purpose}$ ]: Immobilization devices that improve the setup reproducibility of pelvic cancer patients and that provide comfort to patients during radiotherapy were designed and the feasibility of the devices was evaluated. $\underline{Materials\;and\;Methods}$: A customized device was designed to immobilize a knee, thigh, and foot of a patient. Sixty-one patients with prostate cancer were selected and were divided into two groups-with or without devices. The setup errors were measured with respect to bony landmarks. The difference between digitally reconstructed radiographs (DRR) and simulation films, and the differences between DRR and portal films were measured. $\underline{Results}$: The left-right (LR), anterior-posterior (AP) and craniocaudal (CC) errors between the DRR and simulation films were $1.5{\pm}0.9\;mm$, $3.0{\pm}3.6\;mm$, and $1.6{\pm}0.9\;mm$, respectively without devices. The errors were reduced to $1.3{\pm}1.9\;mm$, $1.8{\pm}1.5\;mm$ and $1.1{\pm}1.1\;mm$, respectively with the devices. The errors between DRR and portal films were $1.6{\pm}1.2\;mm$, $4.0{\pm}4.1\;mm$, and $4.2{\pm}5.5\;mm$, respectively without the devices and were reduced to $1.0{\pm}1.8\;mm$, $1.2{\pm}0.9\;mm$, and $1.2{\pm}0.8\;mm$, respectively, with the devices. The standard deviations among the portal films were 1.1 mm, 2.1 mm, and 1.0 mm at each axis without the devices and 0.9 mm, 1.6 mm and 0.8 mm with the devices. The percentage of setup errors larger than 3 mm and 5 mm were significantly reduced by use of the immobilization devices. $\underline{Conclusion}$: The designed devices improved the setup reproducibility for all three directions and significantly reduced critical setup errors.