• Journal of Plant Biotechnology
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• v.32 no.3
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• pp.151-159
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• 2005

Injury caused by reactive oxygen species (ROS), known as oxidative stress, is one of the major damaging factors in plants exposed to environmental stress. Chloroplasts are specially sensitive to damage by ROS because electrons that escape from the photosynthetic electron transfer system are able to react with relatively high concentration of $O_2$ in chloroplasts. To cope with oxidative stress, plants have evolved an efficient ROS-scavenging enzymes such as superoxide dismutase (SOD) and ascorbate peroxidase (APX), and low molecular weight antioxidants including ascorbate, glutathione and phenolic compounds. To maintain the productivity of plants under the stress condition, it is possible to fortify the antioxidative mechanisms in the chloroplasts by manipulating the antioxidation genes. A powerful gene expression system with an appropriate promoter is key requisite for excellent stress-tolerant plants. We developed a strong oxidative stress-inducible peroxidase (SWPA2) promoter from cultured cells of sweetpotato (Ipomoea batatas) as an industrial platform technology to develop transgenic plants with enhanced tolerance to environmental stress. Recently, in order to develop transgenic sweetpotato (tv. Yulmi) and potato (Solanum tuberosum L. cv. Atlantic and Superior) plants with enhanced tolerance to multiple stress, the genes of both CuZnSOD and APX were expressed in chloroplasts under the control of an SWPA2 promoter (referred to SSA plants). As expected, SSA sweetpotato and potato plants showed enhanced tolerance to methyl viologen-mediated oxidative stress. In addition, SSA plants showed enhanced tolerance to multiple stresses such as temperature stress, drought and sulphur dioxide. Our results strongly suggested that the rational manipulation of antioxidative mechanism in chloroplasts will be applicable to the development of all plant species with enhanced tolerance to multiple environmental stresses to contribute in solving the global food and environmental problems in the 21st century.

• Journal of Life Science
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• v.25 no.1
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• pp.44-52
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• 2015

In the present study, the substance that show anti-proliferation of cancer cells as well as anti-oxidant and anti-inflammatory effect was searched. As a results, the methanol extract of Pogostemon cablin (P. cablin), is a well-known herb for traditional medicine in Korea and China for treating the digestive disorders, less of appetite, vomiting and diarrhea, inhibited the growth of various cancer cells such as A549, HepG2, MCF7 and HT29 cells. Cytotoxic effect of methanol extraction of P. cablin was excellent in A549 cells. P. cablin extract induced cell cycle arrest at G1 phase of A549 in a dose dependent manner. And it induced phosphorylation of p38 and Cdc25A and reduced expression of Cdc25A, Cdks, Cyclins and phospho-Retinoblastoma (Rb) proteins. Therefore, P. cablin extract seems to act through the p38 - Cdc25A - Cdk - Cyclin - Rb pathway in A549 cells. In addition, P. cablin extract showed anti-oxidant effect by DPPH free radical scavenging assay and anti-inflammation effect by inhibition of lipopolysaccharide (LPS)-induced nitric oxide (NO) in RAW 264.7 cells in a dose-dependent manner. Taken together, these results suggest that P. cablin may be used as not only candidate materials for anti-cancer, anti-inflammatory and anti-oxidant, moreover, it would be possible utilized in various health functional food materials.

• Molecules and Cells
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• v.28 no.4
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• pp.383-388
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• 2009

The dehydration responsive element binding protein 2C (DREB2C) is a dehydration responsive element/C-repeat (DRE/CRT)-motif binding transcription factor that induced by mild heat stress. Previous experiments established that overexpression of DREB2C cDNA driven by the cauliflower mosaic virus 35S promoter (35S:DREB2C) resulted in increased heat tolerance in Arabidopsis. We first analyzed the proteomic profiles in wild-type and 35S:DREB2C plants at a normal temperature ($22^{\circ}C$), but could not detect any differences between the proteomes of wild-type and 35S: DREB2C plants. The transcript level of DREB2C in 35S: DREB2C plants after treatment with mild heat stress was increased more than two times compared with expression in 35S:DREB2C plants under unstressed condition. A proteomic approach was used to decipher the molecular mechanisms underlying thermotolerance in 35S:DREB2C Arabidopsis plants. Eleven protein spots were identified as being differentially regulated in 35S:DREB2C plants. Moreover, in silico motif analysis showed that peptidyl-prolyl isomerase ROC4, glutathione transferase 8, pyridoxal biosynthesis protein PDX1, and elongation factor Tu contained one or more DRE/CRT motifs. To our knowledge, this study is the first to identify possible targets of DREB2C transcription factors at the protein level. The proteomic results were in agreement with transcriptional data.

• The Korean Society of Law and Medicine
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• v.12 no.1
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• pp.177-225
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• 2011

Verdicts related to major medical litigation given by the Seoul Central District Court, the Seoul High Court and the Supreme Court in 2010 were analyzed. It's shown that in cases of the medical negligence regarding the occurrence of neonatal cerebral palsy, the plaintiff claims were dismissed using criteria proposed by associations of Obstetrics and Gynecology and Pediatrics in US, and thereof the burden of plaintiffs to prove the medical negligence has increased. In addition, in case of that the expected survival period of infants gets longer, payments for treatment and nursing after survival period determined by judges are made and it was judged to compensate it as a periodical indemnity. In case for the explanation obligation the most frequently mentioned in the medical litigation, in addition to cases of invoking the existing theory of explanation obligation, verdicts to mention the instructions of theory regarding instruction explanation obligation and the possibility of compensation for damages on property are given. Particularly, in cases for a liability of reparation by exaggerating the effects and not disclosing the risks related to treatment with stem cells, even if the treatment not approved by Food and Drug Administration is in violation of the Pharmaceutical Affairs Law, it's not illegal as violation in Pharmaceutical Affairs Law itself. But there is a certain verdict to present the possibility of an extension of the theory of explanation obligation by acknowledging the liability of reparation caused by illegal acts with no explanations of effects and risks of treatment with stem cell by doctors and pharmaceutical companies. In an incident in which a mental patient fell and died through the opened door of the roof at the hospital, a liability of reparation was acknowledged due to defects in structure installation management and this verdict drew an attention since the overall management responsibility about patients including structures was acknowledged to the hospital besides the obligations on medical practice. In case of the verdict without giving the opportunity to state the opinion with respect to the main legal issues, the responsibility of the court was emphasized since the court did not fulfill the explanation obligations. There were some cases in which payments for nursing and caring to a patient in vegetative state during the plastic surgery was admitted. However, in dental-related incidents, the proportion of cases in which plaintiff won was low since the difficulty of proving may be reflected. In the area of administrative litigation, unlike the existing position regarding arbitrary medical charge cover collected from patients in hospital, the verdict to admit the legitimacy of collection of medical treatment was given and attracted the attention of people. Verdict in which the expression related to medical advertisement was not exaggerated disposed the original verdict and pointed out the problem of excessive regulations on medical advertisement. The effort to analyze the trend of verdicts of court through reviewing the decisions and to organize should be continued, but the full decision should be disclosed as a base, and people and systems to enable the all time monitoring should be prepared.

• Journal of The Korean Society of Grassland and Forage Science
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• v.27 no.2
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• pp.109-116
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• 2007

Environmental stress is the major limiting factor in plant productivity. As an effort to solve the global food and environmental problems using the plant biotechnology, we have developed transgenic tall fescue (Festuca arundinacea Schreb.) plants via Agrobacterium-mediated gene transfer method. To develop transgenic tall fescue plants with enhanced tolerance to the environmental stresses, both CuZn superoxide dismutase (CuZnSOD) and ascorbate peroxidase (APX) genes were incorporated in a pIG121 binary vector and the both of the genes were controlled separately by an oxidative stress-inducible sweet potato peroxidase 2 (SWPA2) premoter expressed in chloroplasts. Leaf discs of transgenic plants showed 10-30% less damage compared to the wild-type when they exposed to a wide range of environmental stresses including methyl viologen (MV), $H_2O_2$ and heavy metals. In addition, when $200{\mu}M$ MV was sprayed onto the whole plants, transgenic plants showed a significant reduction of visible damage compared to wild-type plants that were almost damaged. These results suggest that over expression of CuZnSOD and APX genes in transgenic plants might be a useful strategy to protect the crops against a wide range of environmental stresses.

• Journal of Life Science
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• v.21 no.3
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• pp.451-458
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• 2011

Cordycepin (3'-deoxyadenosine), a nucleoside derivative isolated from Cordyceps militaris, is reported to have antitumor effects. However, neither its molecular mechanism nor its molecular targets are well understood. In the present study, molecular mechanisms for the anti-tumor effects of cordycepin were investigated in human prostate cancer PC-3 cells. The MTT assay was used to detect cell viability. Annexin V/FITC assay, reactive oxygen species (ROS) production, mitochondrial membrane potential (MMP), and $Ca^{2+}$ flux were used to assess for the presence of apoptosis. Western blot analysis was used to detect protein expression. Treatment of cordycepin resulted in significantly decreased cell viability of PC-3 cells in a dose- and time-dependent manner. A dose-dependent apoptotic cell death was also measured by flow cytometery analysis. Molecular mechanistic studies of apoptosis unraveled cordycepin treatment resulted in significant mitochondrial dysfunction, ROS production, and elevation of $Ca^{2+}$ concentrations. These phenomena were followed activation of caspase-3, subsequently leading to PARP cleavage and cell apoptosis. Taken together, cordycepin induces apoptosis in PC-3 cells through regulation of a mitochondrial mediated pathway.

• Journal of Life Science
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• v.20 no.6
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• pp.934-939
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• 2010

We have previously reported recombinant productions of bacteriocins using yeast expression plasmid pAUR123, which contains the alcohol dehydrogenase (ADH) promoter, in Saccharomyces cerevisiae cells and their antibacterial activities. In order to improve the antibacterial activities of bacteriocidal yeast cells, a strong glyceraldehyde phosphate dehydrogenase (GPD) promoter gene of S. cerevisiae was amplified and inserted upstream into bacteriocin genes such as the OR-7, Subpeptin JM4-A or JM4-B gene in the corresponding recombinant yeast plasmid. Yeast cells transformed by the recombinant plasmid containing the GPD promoter represented higher antibacterial activities against both Gram positive B. subtilis and Gram negative E. coli cells compared to those transformed by the corresponding recombinant plasmid containing the ADH promoter. Thus, yeast cells harboring the recombinant plasmid containing the GPD promoter constructed in this study could be applied in the food preservative or animal feed industries.

• Journal of Life Science
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• v.24 no.7
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• pp.750-756
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• 2014

Citrus, yield of which is the highest among fruits produced in Korea, is extensively consumed for processed food items. The amount of by-products of citrus produced from the processing within a short period after the harvest is tremendous. These by-products are mostly dumped into land or neglected because of cost involved in processing them. The aim of the present study was to explore the usefulness of the by-products as a new material by examining the anti-inflammatory activity of fermented extracts of citrus peels. The peels of 'unshu' (Citrus unshiu) was fermented with Aspergillus niger and their extracts before or after fermentation were analyzed using HPLC. The analysis showed that neohesperidin level considerably increased and the two new compounds were synthesized after fermentation. The anti-inflammatory activity of the fermented extracts was examined on RAW 264.7 murine macrophage cells stimulated with lipopolysaccharide. Fermented unshu extracts significantly enhanced the decrease of nitric oxide (NO) production, iNOS and COX-2 expression, comparing with those of unfermented extracts. Also TNF-${\alpha}$ and IL-6 production, both of which are pro-inflammatory cytokine, were more inhibited in fermented extracts. These results showed that the fermentation and promotion of the function of the by-products of citrus peels will help find a new application.

• Journal of Life Science
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• v.27 no.10
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• pp.1130-1136
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• 2017

Traditionally, the larvae of Allomyrina dichotoma (AD), a species of the rhinoceros beetle, have been widely used for their antidiabetic, antihepatofibrotic, antineoplastic, and antiobesity effects. The United Nations' Food and Agriculture Organization has reported on the possibility of using edible insects in human dietary supplements in the future. However, despite the growing interest in insect-based bio-active products, the biological activities of these products have rarely been studied. Previously, we reported that AD larvae inhibit the in vitro differentiation of adipocytes via transcription factor downregulation. In this study, our objective was to evaluate the effects of a hot-water extract of AD larvae on allergy and inflammation. To investigate the inhibitory effect of the extract on allergic reactions, we measured the levels of ${\beta}-hexosaminidase$, tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$), interleukin-4 (IL-4), and cyclooxygenase-2 (COX-2) after activation of RBL-2H3 cells using Compound 48/80. In addition, the inhibitory effect of the extract on inflammation was determined using Raw 264.7 cells after lipopolysaccharide (LPS) stimulation. The extract significantly inhibited the ${\beta}-hexosaminidase$, $TNF-{\alpha}$, IL-4, and COX-2 levels in RBL-2H3 cells. Furthermore, it effectively inhibited the inflammatory cytokine IL-6, nitric oxide, and inducible nitric oxide synthase expression in LPS-stimulated Raw 264.7 cells. These results suggest that AD larval extract can be potentially developed as an antiallergic and anti-inflammatory therapeutic agent.

• Journal of Life Science
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• v.27 no.11
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• pp.1357-1368
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• 2017

The purpose of this study was to investigate the anti-obesity and anti-inflammation effect of the cheonggukjang (a soybean paste fermented for only a few days) in diet induced obesity mice. Weight gain was significantly decreased in the mice fed cheonggukjang compared High Fat Diets (HFD). The HFD plus cheonggukjang (CGJ) were also effective in improving the lipid metabolism. The levels of plasma triglyceride, cholesterol, ALT, AST, leptin, glucose, and insulin were significantly lower in CGJ than HFD group (p<0.05). The adiponectin level of CGJ group was significantly increased compared to the HFD group (p<0.05). In the CGJ group, the mRNA expression of adipogenic genes in the liver and adipose tissues, which are transcription factors crucial for adipogenesis, were significantly suppressed (p<0.05). The number of $CD11b^+F4/80^+$ T cells, $Gr-1^{int}CD11b^{high}$ cells, and $Gr-1^{int}CD11b^{high}$ cells were significantly higher in HFD group than CGJ group (p<0.05). The size of adipocyte was significantly reduced in CGJ group compared to HFD group. In addition, the contents of liver lipid droplets were significantly downregulated in the CGJ mice than HFD mice (p<0.05). Collectively, these data suggest the novel function of cheonggukjang in modulating adipogenesis through an immune function-alteration involving downregulation of adipogenic transcription factors and macrophage activation.