• The Korean Journal of Pesticide Science
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• v.17 no.4
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• pp.428-434
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• 2013

An isolate of Bacillus amyloliquefaciens subsp. plantarum CC110 was selected as an effective antagonist for biological control of cucumber downy mildew caused by Pseudoperonospora cubensis. Temperature range for growth of CC110 isolate was $7.5{\sim}55.0^{\circ}C$, and its optimal temperature at $36.6^{\circ}C$. pH range for growth of CC110 isolate was 4.5~9.5, and its optimal pH at 7.0. In this study, the most effective sources of carbon and nitrogen for growth of CC110 isolate were fructose and yeast extract, respectively. The volatile of CC110 isolate was found to be effective to control downy mildew on cucumber showing no diseased area whereas that of control was 13.2% using the I plate bioassay. The culture broth and cells of isolate CC110 cultured in TSB media for 48 hours at $28^{\circ}C$ inhibited occurrence of cucumber downy mildew. The cells and culture broth were transformed into sporangia of P. cubensis by in observation under light microscope and scanning electron microscope.

• Journal of Life Science
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• v.14 no.3
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• pp.396-399
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• 2004

This study was investigated the changes of root length, tissue structure of root tip, and dry matter production of a Dongjinbyeo (DJ) cultivar subjected to 0.4 % agar medium with various concentration of NaCl (salt stress)- and polyethylene glycol 6000 (PEG, drought stress). Root length and dry weight of DJ plant were declined along the high concentration of PEG and NaCl in rice plants. To elucidate the changes of tissue structure in root tip to PEG- and NaCl-treatments, we examined the microscopic observation of root tip in NaCl- and PEG-treated rice plants using Toluidine blue O. By Toluidine blue O staining, methyl-lignin accumulation was found in the epidermis and outer cortex of the elongation zone at an early stage of PEG treatment, whereas was found only the outer cortex of the elongation zone of NaCl-treated root tip. The epidermis of NaCl-treated root tip became soften instead of methyl-lignin accumulation. TR ratio was increased along the high concentration in PEG- and NaCl-treated rice plant as a result of inhibited root elongation under PEG- and NaCl-treatment. From these morphological changes in root stimulated by drought and salt stress, we suggest that agar medium is useful to identify tolerant variety in germination stage under stressful environments.

• Journal of Life Science
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• v.15 no.5 s.72
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• pp.755-762
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• 2005

Biochemical amounts of RNA molecules can be synthesized in vitro, which is functionally equivalent or similar to those transcripts normally existing at extremely low levels in vivo. In this study we described a method for efficient preparation of pure T7 RNA polymerase from Escherichia coli strain BL21/pAR1219. The procedure, which used ammonium sulfate fractionation and preparative column chromatography on sephadex SP, was shown to be simple, rapid, and cost effective in comparison with other methods reported previously, Using the purified T7 RNA polymerase we were able to synthesize very long RNA transcript of 1.54 kb length, which is not feasible by conventional chemical synthesis. RNA molecule that was also synthesized by the purified T7 RNA polymerase, such as hammerhead ribozyme, retained its biochemical activity by cleaving the target RNA successfully in vitro. Thus, the procedure shown in this study can be useful to synthesize any length of RNA molecules in vitro in a simple and cost effective way for a variety of purposes.

• Korean Journal of Ecology and Environment
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• v.43 no.3
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• pp.409-417
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• 2010

Present study aimed to investigate morphological and physiological change in the tissues of Carassius auratus after exposure against Pb (lead) with various rearing condition. We measured the level of accumulated heavy metal and analyzed ultrastructure with transmission electron microscopy. The heavy metal, Pb, was accumulated in the gill, bone and integument increased drastically for exposure periods, the 40 days. The accumulation of Pb in the gill showed relatively higher than that in other tissues. And accumulated Pb amounts also were increased with exposure time dependent manner in the gill, bone and integument tissues. Also, specific activities of antioxidation enzymes in all tissue after exposure to Pb were increased in the course of exposure. And the activities of SOD from tissues exposed to Pb were increased 2 folds than those from the unexposed but GPX activities were maintained constant. The increased numbers of mucous cells in gill tissues exposed to Pb were determined and morphological changes, such as clubbing and fusion, were shown secondary lamella. Also, exposure of Pb for 40 days on gills tissues cause membrane damage in mitochondria and nucleus. In kidney tissues, the atrophied glomerulus was observed, and the empty space in Bowman's capsule was expanded. Based on the all results, it is suggested that the exposure to the high level of Pb for long period affect on the morphology of tissues, and change the enzymatic balance in C. auratus.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.11a
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• pp.143-143
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• 2003

최근 생활수준 및 생활환경의 향상에 힘입어 청결 및 쾌적을 추구하는 것이 사회적 현상으로 나타나고 있다. 요즘처럼 현대화된 시대에 '왜 항균제가 필요한 것일까' 라는 자연스러운 의문이 발생하게 되지만 현실은 항균제를 이용한 다양한 항균제품, 항균가전제품, 항균가공 내ㆍ건자재 및 항상 신선한 선도를 유지할 수 있는 제품 등이 호황을 누리고 있는 것이 현실이며 그 시장 규모는 3,000억원을 상회하고 있다. 이러한 항균 가공제품이 호평을 받는 사회적 배경은 우리를 둘러싼 주변 삶의 경제환경 신장에 따른 쾌적성 추구와 밀접한 관련이 있을 것이다. 이처럼 항균기능이 부여된 제품이 호평을 받고 있음에도 불구하고 국내에서는 항균제품의 주 기능 역할을 하는 항균제에 대한 개발은 초기단계로 국내 시장에서 많은 연구가 이루어지고 있는 실정이다. 국내의 경우, 유기 항균제의 사용이 전체 사용량의 80%를 차지하고 있고, 제올라이트나 인산염을 무기 담체로 항균성 금속 이온(Ag, Zn)을 물리적으로 결합시킨 무기 항균제가 개발된 것이 최근의 기술 수준이다. 이러한 유기 항균제는 미생물의 번식을 억제 또는 사멸시키기 위한 것이지만, 생체의 피부 세포에도 영향을 줄 수 있는 피부 자극원의 하나로 그 사용이 점차로 제한되고 있다. 무기 항균제는 안정성이나 항균력에서는 유기항균제 보다는 뛰어나지만 가격(경제성)이나 색(Color), 사용성 (Application)측면에서는 여러 가지 문제를 나타내고 있다. 귀금속이므로 가격이 고가이며, 금속고유의 색으로 회귀하려는 플라즈몬 효과에 의해 색(Color)의 조절이 불가능, 분말형태이므로 지류에 첨가시키는 방법 등이 큰 문제로 부각되고 있다. 이 러한 문제점을 해결할 수 있는 기술이 나노기술이다 나노기술(Nano-Technology)은 물질을 분자, 원자단위에서 규명하고 제어하는 기술로서 원자, 분자를 적절히 결합시킴으로서 기존 물질의 변형, 개조는 물론 신물질의 창출을 가능케 하는 기술이다. 나노기술은 여러분야로 세분화되지만 그중 산업화에 가장 접목이 용이한 기술이 나노입자(Nano-Particle)제어 기술이며, 나노입자는 통상적으로 입자크기가 수 nm에서 100nm이하 크기의 넓은 표면적을 가진 콜로이드 상의 불균일 분산입자를 말한다. 나노입자(Nano-Particle)는 기존의 입자($\mu\textrm{m}$)보다 물리적 및 광학적 성질이 우수하고 그 자체의 기능면에서도 탁월하기 때문에 국내외의 여러 산업에서도 기존제품의 품질 향상 및 기능성부여, 기존 공정의 개선 및 생산 원단위 절감 등 경제적, 생산적인 측면을 고려하여 적합한 나노입자를 채택, 적용하고자 하는데 많은 노력을 기울이고 있다. 이에 천연 항생제로 알려진 Ag, 즉 항균 및 탈취, 전기적 기능이 우수한 은(silver, Ag)을 나노(nm) 입자희 제조하고 이와 더불어 이산화티탄(TiO2) 복합 분체를 제조하여 제조된 나노 입자 및 복합 분체를 사용함으로써 환경 친화적이며 다양한 용도로 활용 가능한 소재 개발에 연구 내용을 두고 있다. 본 연구를 통한 기대 효과로서 환경성 측면에서는 환경 친화적인 나노 입자의 제조로 기능성 나노 입자에 친 환경성을 부여하여 유기계 항균제 대체 효과를 발현하고 이를 제품에 적용함으로써 다양한 기능을 가진 신소재 제조에 있다. 또한 경제적인 측면에서도 고부가 가치의 제품 개발에 따른 새로운 수요 창출과 수익률 향상, 기존의 기능성 안료를 나노(nano)화하여 나노 입자를 제조, 기존의 기능성 안료에 대한 비용 절감 효과등을 유도 할 수 있다. 역시 기술적인 측면에서도 특수소재 개발에 있어 최적의 나노 입자 제어기술 개발 및 나노입자를 기능성 소재로 사용하여 새로운 제품의 제조와 고압 기상 분사기술의 최적화에 의한 기능성 나노 입자 제조 기술을 확립하고 2차 오염 발생원인 유기계 항균제를 무기계 항균제로 대체할 수 있다. 이와 더불어 안료의 형상 균일화 기술을 확보하여 가격 경쟁력 및 부가가치 향상을 기대할 수 있다.

• The Journal of the Korean bone and joint tumor society
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• v.17 no.2
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• pp.65-72
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• 2011

Purpose: We evaluated the complications of allograft reconstruction after a bone tumor resection, and reviewed literatures to overcome such complications. Materials and Methods: We retrospectively reviewed clinical records and radiographs of fifteen patients in whom reconstruction with allograft after bone tumor resection. Results: Eight patients were men and seven were women with a mean age of 27.1 years (1-56 years) and a mean follow-up period of 89.5 months (33-165 months). All postoperative complications related to the allograft were recorded. Twenty patients (80.0%) obtained a radiologic bony union at a mean of 8.35 months (4-12 months). The mean Musculoskeletal Tumor Society score was 73.5% (46.6-93.0%). Nine patients (60.0%) experienced one event and 3 (20.0%) patients experienced multiple events during the follow-up period. Recorded events were infection (3), fracture (2), nonunion (2), limb length discrepancy (2) and varus deformity (2). The mean event free survival period was 60.8 months (6-144 months). The mean allograft survival period was 80.2 months and the 5 year survival rate of the allografts was 83.0%. Conclusion: In order to overcome complications, the combination of an allograft and vascularized fibular graft is highly recommended. In the near future, the tissue engineering technique, the application of the stem cell and PRP, could reduce the complication of allograft such as resorption and nonunion.

• Current Research on Agriculture and Life Sciences
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• v.10
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• pp.125-135
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• 1992

Nine strains of xyl mutants that could not utilize xylose as a carbon source were isolated from E. coli JM109 by the treatment of NTG in order to investigate the regulation of xylose operon and to use recipient cells for the cloning of xylR gene. For the characterization of all isolated mutants, colony colors of all mutants on MacConkey-xylose and MacConkey-xylulose agar plate were observed for the utilization of xylose and xylulose, and the growth level and the activity of xylose isomerase and xylulokinase were determined in need. The isolated xylR/T mutants formed the white colony on MacConkey-xy-lose and MacConkey-xylulose agar plate. They did not detect the activity of xylose isomerase, and the activity of xylose isomerase was not restored in transformants of xylR/T mutant with pEX13 which contained xylA gene. xylR and xylT mutants were classified from xylR/T mutants depending upon the growth level in minimal medium. xylT mutants; DH13, DH121 and DH125 could grow a little in that medium, but xylR mutants; DH10, DH53, and DH60 could not grow that medium.

• Journal of Plant Biotechnology
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• v.35 no.2
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• pp.133-140
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• 2008

The modification of DNA and histone plays an important role for gene expression in plant development. The objective of this research is to observe the effects of methylation on the gene expression during dedifferentiation from rice mature seeds to callus and differentiation from callus to shoots. The embryogenic callus with ability to shoot regeneration was not induced on the N6A medium supplemented with 5-azacytidine and abnormal callus with brown color was formed. When the normal rice callus was placed on the regeneration MSRA medium supplemented with 5-azacytidine, the shoot regeneration was inhibited. The results showed that 5-azacytidine, DNA demethylating agent, had negative effects on normal embryogenic callus formation and shoot regeneration. This suggested that DNA methylation of some genes was required for normal cell dedifferentiation and differentiation in tissue culture. The microarray and $GeneFishig^{TM}$ DEG screening were used to observe the gene transcript profile in callus induction and regeneration on N6A (N6 medium + 5-azaC) and MSRA (MS regeneration medium + 5-azaC). Subsets of genes were up-regulated or down-regulated in response to 5-azaC treatments. The genes related with epigenetic regulation, electron transport, nucleic acid metabolism and response to stress were up and down regulated. The different expression of some genes (germin like protein etc.) during callus induction and shoot regeneration was confirmed using RT-PCR and northern blot analysis.

• Korean Journal of Animal Reproduction
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• v.18 no.2
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• pp.141-150
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• 1994

Morphological features of the interaction between the hatching blastocyst and implantation in pig were studied by electron microscopy. The observations extended from late blastocyst stage to the completion of trophoblastic erosion of the epithelium and early decidual transformation of the epithelium and early decidual transformation of the stromal cells. Between day 7 and 17 of pregnancy, blastocysts from 0.3 to 12 mm in diameter were flushed from the uterine horns of Dutch Landrace pigs. On the 7th of development in the pig blastocyst, the blastocyst shedded of the zona pellucida established the tips of microvilli and with bleb-like cytoplasmic protrusions of the epithelial cells. From day 11 on in pig embryo, the bilayered trophoblast undergoes a dramatic phase of elongation so that the initially spherical expanded blastocyst becomes tubular. In pig, close apposition to the uterine wall beg-ins at about 12 $^1$/$_2$ days and then attachment occurred during the afternoon of the 16th or 18th day post coitum. At this stage, embryonic loss compared with corpus luteum number is up to 40% of ovulated oocytes. Therefore, the implantation failture of these embryos may be mainly caused by morphological abnormality and failture of zona shedding.

• Journal of Oral Medicine and Pain
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• v.37 no.1
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• pp.9-17
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• 2012

Lichen planus is a chronic inflammatory mucocutaneous disease that affects multiple sites of the body. Often it involves the oral mucosa, but also involve other sites such as skin, genitals, scalp and nails. There is no clear cause of oral lichen planus (OLP), current data suggest that OLP is a T-cell mediated autoimmune disorder which may have an altered self-peptide triggering apoptosis of oral epithelial cells. Usually OLP appears in middle-aged women which tends to be chronic with periods of exacerbation and remission. There are many theories those causes the OLP such as psychological and environmental factors, genetic tendency, drugs and more. 60-70% of lichen planus is accompanied by oral lesions, and more than half of its cases are not able to defined by their skin. In this study, among all the possibility(possible) theories, we tried to evaluate the influence of emotional stress in exacerbating OLP. There were thirty patients with a clinical or histological diagnosis of OLP and other thirty subjects who did not show any signs of systemic disorders include OLP. They were evaluated by using modified Holmes and Rahe's Social Readjustment Rating Scale (SRRS). As a result, a significantly higher level of stress was found in the OLP patients than the control group. Therefore it could be concluded that psychological stressors play an important role in the exacerbating OLP.