• Journal of radiological science and technology
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• v.32 no.1
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• pp.39-43
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• 2009

The medical diagnostic examination using ionizing radiation has improved the patients' life and brought revolution in medical examination along with the mechanical development. However, the development of medical imaging systems has also been the reason to increase the patients' exposure for ionizing radiation. ICRP recommends that each country adopts diagnostic reference levels depending on regional and national situations. The Korea Food & Drug Administration suggested the dosimetry measurement guideline for patients in 2007. Nonetheless, in reality, it is hard to know the skin dose of the patients when applying a x-ray since there is no radiation dosimeter in most of clinical situation. Therefore, this study sets a program based on the bit system to figure out easily the skin dose of a patients using MS Excel program in the PC setting. The results showed 10% better outcome.

• Polymer(Korea)
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• v.34 no.1
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• pp.63-68
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• 2010

In this study, we evaluated the effect of fibrin, a natural material, on the local inflammatory reaction of PLGA in vivo. PLGA degradation products can decrease the pH in the surrounding tissue, causing local inflammatory reaction. To solve this problem, fibrin/PLGA scaffolds were implanted in 5-week-old Wister rats. To evaluate the influence of fibrin content on inflammatory cytokine expression induced by PLGA, RT-PCR analysis was used. Fibrous wall thickness and macrophage infiltration were evaluated by H&E and ED-1 immunohistochemical staining, respectively. In this study, we showed that fibrin/PLGA scaffolds reduced inflammatory reaction as compared to PLGA scaffold. We concluded that fibrin could reduce inflammatory response of PLGA.

• KSBB Journal
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• v.21 no.6 s.101
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• pp.405-409
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• 2006

Bokbunja (Rubus coreanus Miquel) is a wild berry belonging to Rosaceae genus of which application areas have been expanded due to many health effects. Bokbunja berry contains carbohydrates, protein, fats and dietary fibers as major components and various flavonoids such as tannins, volatile components including organic acids, alcohols and hydrocarbons as minor ones. Those active compounds attribute to the following health effects: increase in immune function and antioxidant activity, rise in hormone secretion, suppression of the growth of type B hepatitis virus, and control of weight gain. To utilize the above activities, many products have been developed by using Bokbunja berry extracts in the area of foods, liquors, and cosmetics. Recently, pure compounds have been isolated from the extracts for the development of medicines. In this mini review, the state-of-the-art of Bokbunja researches and applications including papers and patents is summarized.

• KSBB Journal
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• v.28 no.5
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• pp.332-337
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• 2013

The gene encoding for xylose isomerase from the thermophilic bacterium Thermotoga maritima was cloned and recombinantly expressed in E. coli cells. Optimal activity was shown at $90^{\circ}C$ and pH 8.0. Treatment of saponin by recombinant xylose isomerase increased the growth inhibitory effect against human gastric cancer (AGS) cells and human colon cancer (HT-29) cells. On the other hand, treatment of fucoidan by the enzyme could not change the growth inhibitory effect against the same cancer cells. One ${\mu}g/ml$ of enzyme-treated saponin exhibited the same or higher growth inhibitory effect against both cancer cells compared with 100 ${\mu}g/ml$ of enzymeuntreated saponin. These results would be useful in the development of functional food or drug.

• Journal of Life Science
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• v.18 no.11
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• pp.1617-1624
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• 2008

Chitin and chitosan, which is deacetylated form of chitin, are one of the most abundant biomass on the earth. They showed various biological activities including antimicrobial activity, heavy metal chelating, immune system activation, and have very diverse applications in food, pharmaceutical, medicinal, and environmental industry. There have been reported many chitin/chitosan-hydrolyzing enzymes, their structures and genes from three domains, archaea, bacteria, and eukarya. Carbohydrate hydrolyzing enzymes are classified in CAZy (Carbohydrate Active Enzymes) database according to their amino acid sequence similarity. Interestingly, chitinases and chitosanases are classified in various glycosyl hydrolase(GH) families, GH2, GH5, GH7, GH8, GH18, GH19, GH20, GH46, GH48, GH73, GH75, GH80, GH84, and GH85. Here, we review characteristics and structures of chitin/chitosan hydrolyzing enzymes according to glycosyl hydrolase families in order to provide information about gene mining.

• Journal of Chest Surgery
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• v.39 no.6 s.263
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• pp.482-485
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• 2006

Video-assisted thoracoscopic surgery has gained a broad acceptance for various thoracic lesions because it is the minimally invasive surgery with little tissue trauma, less pain, improved cosmetic results and short recovery time. However, there are some limitations for this method, such as restricted visual sensory information to a two-dimensional image and limited maneuverability of the tips of the instruments. To overcome these limitations, advanced technology has been introduced and the da $Vinci^{TM}$ Surgical System (Intuitive Surgical Inc, Mountain View, CA, USA) became available in 2001. In Korea, the da $Vinci^{TM}$ Surgical System was introduced in Severance hospital (Yonsei University College of Medicine) in May 2005, and approved by KFDA in July 2005. Herein, we report the first experience of robot-assisted thoracic surgery with the da $Vinci^{TM}$ Surgical System in extirpation of a large teratoma in anterior mediastinum.

• KSBB Journal
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• v.14 no.3
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• pp.291-296
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• 1999

Chiral epoxides are key intermediates for the production of chiral pharmaceuticals, agrochemicals, and functional food additives. Chiral epoxides can be produced by either chemical or biological method. In biocatalytic production routes, chiral epoxides can be produced via epoxidations of prochiral alkenes by monooxygenase or peroxidase. Kinetic resolution of racemic epoxides using whole cells of bacteria or fungi might be commercially useful, since it is possible to obtain chiral epoxides with high optical purities from relatively cheap and readily avaiable racemic epoxides. Some bioprocesses already are commercially developed: the biocatalytic production of chiral epichlorohydrin via microbial stereospecific dehalogenation, and lipase-catalyzed enantioselective hydrolysis in a hollow fiber membrane bioreactor for the production of chiral methyl trans-3-(4-methoxyphenyl)glycidate. the intermediate for calcium antagonist diltiazem. The importance of biocatalytic production of chiral epoxides with several examples from literature are presented.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.534-537
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• 2002

An agarase gene from Bacillus cereus ASK202 was expressed in high levels by E. coli BL21(DE3)/pEBA1 using pET28a(+) vector system with the inducible T7 promoter in the presence of isopropyl- ${\beta}$ -thiogalactopyranoside. The open reading frame encodes 761 amino acid residues with a calculated molecular weight of 83,300 daltons and a potential signal peptide about 36 amino acid residues at the N-terminus. E. coli BL21(DE3)/pEBA1 produce 1280 unit/ ${\ell}$ of agarase. The optimum physical condition for the agarase activity was pH 5.6, and $40^{\circ}C$, respectively. The agarase activity was stable up pH $4.0{\sim}9.0$ and $4{\sim}40^{\circ}C$. The km and maximum rate of metabolism for agar were 0.068mg/$m{\ell}$ and 0.094mg/$m{\ell}{\cdot}min$, respectively.

• Korean Chemical Engineering Research
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• v.44 no.1
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• pp.81-86
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• 2006

This study was carried out to investigate the antimicrobial and antioxidant activities for applications of food additives and medicine using Rumex crispus which widely grown in domestic area. Antimicrobial activities of extract fractions were observed in all microbial species except for Pseudomonas areuginosa. Especially, Vibrio vulificus and Saccharomyces cerevisiae presented obvious antimicrobial activity. Antioxidant activities of the fractions of R. crispus extract were determined by DPPH radical scavenger activity. The fraction of ethyl acetate was presented similar antioxidant activities compared with that of BHA and ascorbic acid. Also, ethyl acetate fraction contained higher phenolic compounds than that of others. The antioxidant activity in the fractions of R. crispus extract was closely related with the content of phenolic compounds in that.

• Korean Journal of Medicinal Crop Science
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• v.11 no.2
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• pp.127-134
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• 2003

One hundred sixty species among Korean medicinal plants were tested on their antioxidative potentials. Antioxidants are useful materials which could be expected into development as food preservatives, health foods, cosmetics and drugs. Korean peninsula have many potential in antioxidant source which includes various medicinal herbs. It grounded on the fact that Korean medicinal plants have been used as folk therapy for long time and still do in oriental medicine. From the study, effective free radical scavengers compared with ${\alpha}-tocopherol\;of\;13.5{\mu}g/ml\;in\;RC_{50}$ were Geranium sibiricum, Geum japonicum, Geranium nepalense subsp. thunbergii and Paulownia coreana which showed $19.3{\mu}g/ml,\;22.5{\mu}g/ml,\;23.9{\mu}g/ml,\;and\;27.2{\mu}g/ml$, respectively, Acer mono and 38 plants showed strong potential in inhibition rate on linoleic acid oxidation (above 90%). In conclusion, we expect that the selected medicinal plants must be more studied as antioxidant and then developed as many industrial materials.