• Journal of Life Science
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• v.19 no.1
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• pp.21-33
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• 2009

In this study, we investigated the effect of Rhei Rhizoma (RR; 大黃) water extract on gene expression in a hypoxia model of cultured rat hippocampal neurons. RR water extract $(2.5{\mu}g/ml)$ was added to the culture media on day 10 in vitro (DIV10), and a hypoxic shock (2% $O_2$/5% $CO_2$, $37^{\circ}C$, 3 h) was given on DIV13. After maintaining the cultures in normoxia for 24 hr, total RNA was isolated and used for microarray analysis. The MA-plot indicated that most genes were up- or downregulated within 2-fold. There were more downregulated genes (725 ea) than upregulated ones (472 ea) when larger than Global M value 0.2 (i.e., >15% increase) or smaller than Global M value -0.2 (i.e., >15% decrease) were considered. Antiapoptosis genes such as Tegt (2.4-fold), Nfkb1 (2.4-fold) Veg (1.8-fold), Ngfr (1.6-fold) were upregulated, while pro-apoptosis genes such as Bad (-64%), Cstb (-66%) were downregulated. Genes for combating environmental stress (stress response genes) such as Defb3 (2.7-fold), Cygb (2.2-fold), Ahsg (2.18-fold), Alox5 (2-fold) were upregulated. Genes for cell proliferation (cell cycle-related genes) such as Erbb2 (1.84-fold), Mapk12 gene (1.8-fold) was upregulated. Therefore, RR water extracts upregulate many pro-survival genes while downregulating many pro-death genes. It is interpreted that these genes, in combination with other regulated genes, can promote neuronal survival in a stress such as hypoxia.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.19 no.1
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• pp.66-75
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• 2014

This study aims to understand environmental factors that determine spatial distribution of macrozoobenthic community in the southern area (ca 100-500 m depth) of East Sea, Korea, known as a candidate site for carbon storage under the seabed. From sixteen locations sampled in the summer of 2012, a total of 158 species were identified, showing density of $843indiv/m^2$ and biomass of $26.2g\;WW/m^2$, with increasing faunal density towards biologically higher diverse locations. Principal component analysis showed that a total of 33 environmental parameters were reduced to three principal components (PC), indicating sediment, bottom water, and depth, respectively. As sand content was increasing, number of species increased but biomass decreased. Six dominant species including two bivalve species favored high concentrations of ${\Omega}$ aragonite and ${\Omega}$ calcite, indicating that the corresponding species can be severely damaged by ocean acidification or $CO_2$ effluent. Cluaster analysis based on more than 1% density dominant species classified the entire study area into four faunal assemblage (location groups), which were delineated by characteristic species, including (A) Ampelisca miharaensis, (B) Edwardsioides japonica, (C) Maldane cristata, (D) Spiophanes kroeyeri, and clearly separated in terms of geography, bottom water and sediment environment. Overall, a discriminant function model was developed to predict four faunal assemblages from five simply-measured environmental variables (depth, sand content in sediment, temperature, salinity and pH in bottom water) with 100% accuracy, implying that benthic faunal assemablages are closed linked to certain combinations of abiotic factors.

• Journal of the Korean Chemical Society
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• v.66 no.2
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• pp.78-85
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• 2022

Natural white clay was treated with 6 M of H₂SO₄ and heated at 80℃ for 6 h under mechanical stirring and the resulting acid active clay was used as an adsorbent for the removal of Cs⁺ in water. The physicochemical changes of natural white clay and acid active clay were observed by X-ray Fluorescence Spectrometry (XRF), BET Surface Area Analyser and Energy Dispersive X-line Spectrometer (EDX). While activating natural white clay with acid, the part of Al₂O₃, CaO, MgO, SO₃ and Fe₂O₃ was dissolved firstly from the crystal lattice, which bring about the increase in the specific surface area and the pore volume as well as active sites. The specific surface area and the pore volume of acid active clay were roughly twice as high compared with natural white clay. The adsorption of Cs⁺ on acid active clay was increased rapidly within 1 min and reached equilibrium at 60 min. At 25 mg L^- of Cs⁺ concentration, 96.88% of adsorption capacity was accomplished by acid active clay. The adsorption data of Cs⁺ were fitted to the adsorption isotherm and kinetic models. It was found that Langmuir isotherm was described well to the adsorption behavior of Cs⁺ on acid active clay rather than Freundlich isotherm. For adsorption Cs⁺ on acid active clay, the Langmuir isotherm coefficients, Q, was found to be 10.52 mg g^-1. In acid active clay/water system, the pseudo-second-order kinetic model was more suitable for adsorption of Cs⁺ than the pseudo-first-order kinetic model owing to the higher correlation coefficient R² and the more proximity value of the experimental value q_e,exp and the calculated value q_e,cal. The overall results of study showed that acid active clay could be used as an efficient adsorbent for the removal of Cs⁺ from water.

• Progress in Medical Physics
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• v.19 no.2
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• pp.95-101
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• 2008

In this study, we observed the alteration of choline signal intensity in hippocampus region of the depressive rat model induced by forced swimming test (FST). The purpose of this study was to evaluate the antidepressant efficacy in the depressive animal model using MR spectroscopy. Fourteen experimentally naive male Sprague-Dawley rats weighting $160{\sim}180\;g$ were used as subjects. Drug injection group was exposed to the FST except for control group. The drugs were administered subcutaneously (SC) in a volume equivalent to 2ml/kg. And three injections were administered 23, 5, and 1h before beginning the given test. 1H MR spectra were obtained with use of a point resolved spectroscopy (PRESS) localization sequence performed according to the following parameters: repetition time, 2500 ms; echo time, 144 ms; 512 average; 2048 complex data points; voxel dimensions, $1.5{\times}2.5{\times}2.5\;mm^3$ ; acquisition time, 25min. There were no differences in NAA/Cr and Cho/Cr ratio between the right and the left hippocampus both normal control rats and antidepressant-injected rats. Also, no differences were observed in NAA/Cr and Cho/Cr ratio between the normal control rats and the antidepressant-injected rats both the right and the left hippocampus. In this study, we found the recovery of choline signals in the depressive animal model similar to normal control groups as injecting desipramine-HCl which was antidepressant causing anti-immobility effects. Thus, we demonstrated that MR spectroscopy was able to aid in evaluating the antidepressant effect of desipramine-HCl.

• Korean Journal of Weed Science
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• v.13 no.2
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• pp.104-113
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• 1993

The experiment was conducted in 1992 to find out the approach to the development of prediction model of weed population in paddy fields. The weed seeds of 88% over were separated from the soil by using $K_2CO_3$ 50% solution with specific gravity 1.34. The weed seeds which were floated on the solution due to the difference of specific gravity between soil particles and the seeds were effectively withdrawn by using a vaccum pump attached with an aspirator. The seeds withdrawn together with solution were taken by filtering with a nylon net of $0.31{\times}0.16mm$ mesh. The pressing method was more efficient and practical for the viability test of weed seeds separated from the soil compared with the germination test and the TTC test. For the prediction of weed population by the number of weed seedlings emerged at the sampled soil, the sampling method of 0-10cm deep at 5-6 sites per field was applicable. At the prediction method by the number of seedlings emerged, the smaller the seed sizes, the lower the prediction coefficients of weed species. It was considered that the prediction method by the number of seedlings emerged was more practical than the prediction method by the number of seeds separated from sampled soil, in relation to similarities to weed population, time and expenses required for examining, technical difficulties and applicability of weed species.

• Radiation Oncology Journal
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• v.26 no.4
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• pp.257-262
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• 2008

Purpose: Oral mucositis induced by radiotherapy to the head and neck area, is a common acute complication and is considered as the most severe symptom for cancer patients in the early stages of treatment. This study was proposed to establish the oral mucositis mouse model induced by a single dose of radiation for the facility of testing therapeutic candidates which can be used for the oral mucositis treatments. Materials and Methods: Fifty-five BALB/c mice were divided into four groups: control, 16 Gy, 18 Gy, and 20 Gy. Oral mucositis was induced by a single dose of radiation to the head and neck using 6 MV x-Ray from linear accelerator. After irradiation, body weight and physical abnormalities were checked daily. Tongue tissues from all groups were taken on days 1, 2, 3, 5, 7, 9, and 14, respectively and H&E staining was conducted to examine morphological changes. Results: Body weight dramatically decreased after day 5 in all irradiated mice. In the 16 Gy treatment group, body weight was recovered on day 14. The histology data showed that the thickness of the epithelial cell layer was decreased by the accumulated time after radiation treatment, up to day 9. Severe ulceration was revealed on day 9. Conclusion: A single dose of 16 Gy is sufficient dose to induce oral mucositis in Balb/C mice. Significant changes were observed in the Balb/C mice on days 7 and 9 after radiation. It is suggested that this mouse model might be a useful standard tool for studying oral mucositis induced by radiation.

• The korean journal of orthodontics
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• v.37 no.6
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• pp.400-406
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• 2007

The purpose of this experimental study was to evaluate the effect of immediate orthodontic loading on the stability at the bone-implant interface of titanium miniscrews in a rabbit model. Methods: Forty titanium miniscrews (1.6 mm diameter, 8 mm length) were inserted in the tibiae of 10 rabbits. Twenty test group miniscrews were subjected to continuous orthodontic forces of 200g immediately after implantation for a period of 6 weeks. The remaining 20 control group miniscrews were left unloaded for the same follow-up interval. Removal torque values were recorded using a digital torque gauge. An independent t-test was performed. Results: All the miniscrews were stable, and exhibited no mobility or displacement throughout the experimental period. Histologically, miniscrews were well-integrated into bone. No statistically significant differences in removal torque data were found between the loaded test and the unloaded control groups. Conclusions: These findings suggest that titanium miniscrews can be used as anchoring units for orthodontic tooth movement immediately after insertion.

• Korean Journal of Environmental Agriculture
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• v.32 no.3
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• pp.231-239
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• 2013

BACKGROUND: The disease resistant (OsCK1) rice was generated by inserting choline kinase (CK1) and phosphinothricin acetyltransferase (PAT) genes isolated from Oriza sativa and Streptomyces hygroscopicus into the genome of rice (Nakdongbyeo). With the potential problems of safety, the non-target organism evaluation is required as an essential element for the environmental risk assessment of genetically modified (GM) crops. In present study, we studied the effects on survival of Misgurnus anguillicaudatus and Cyprinus carpio, commonly used as a model organism in ecotoxicological studies. METHODS AND RESULTS: The M. anguillicaudatus and C. carpio were fed on disease resistant (OsCK1) rice and non-genetically modified (non-GM) rice (Nakdongbyeo) to 0, 10, 100, 1,000 and 5,000 mg/L, as treatment concentration respectively. The OsCK1 rice used for the test was confirmed to have the OsCK1/PAT gene expression by the PCR and ELISA analysis. Feeding test showed that no significant differences in cumulative immobility and abnormal response of M. anguillicaudatus and C. carpio fed on between OsCK1 rice and non-GM rice. The 96hr-$LC_{50}$ values showed no difference between OsCK1 rice (>5,000 mg/L) and non-GM rice (>5,000 mg/L). CONCLUSION(S): The results of this study suggested that there was no significant difference in toxicity for M. anguillicaudatus and C. carpio between OsCK1 rice and non-GM counterparts.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.2
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• pp.528-533
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• 2004

The immune system acts to protect the host from infectious agents that exist in the environment and from other noxious insults. The immune system has two functional divisions: the innate and the acquired. Both components involve various factors such as cytokines. A number of methodologies exist to assess aspects of immune function. There are large inter-individual variations in many immune functions even among the healthy. Genetics, age, gender, smoking habits, habitual levels of exercise, alcohol consumption, diet, stage in the female menstrual cycle, stress, history of infections and vaccinations, and early life experiences are likely to be important contributors to the observed variation. While it is clear that individuals with immune responses significantly below 'normal' are more susceptible to infectious agents and exhibit increased infectious morbidity and mortality, it is not clear how the variation in immune function among healthy individuals relates to variation in susceptibility to infection. Oriental medicine is an important factor contributing to immune competence. The author investigated the immune enhancement effects of Bojungikkitanggami-bang (BITB). The forced swimming test (FST) has been used as a screening model for new immune enhancement agents. In the present study, the author investigated the effects of BITB on FST and blood biochemical parameters related to fatigue, glucose (Glc); blood urea nitrogen (BUN); lactate dehydrogenase (LDH); creatinine; and total protein (TP). The author found that BITB (1 g/kg) significantly reduced the immobility time in the FST compared to the control. In addition, the contents of Glc, LDH, BUN, TP in the blood serum were increased in BITB (1g/kg)-fed group. Also, the author investigated the effects of BITB on the production of cytokines in human T-cell line, MOLT-4 cells. BITB (1 mg/ml) significantly increased the interferon (IFN)-vproduction compared with media control (about 2.2-fold for IFN-γ) at 24 h. However, BITB has not affect the production of IL-2 and IL-4. In addition, BITB increased the protein expression level of IFN-γ in MOLT-4 cells. Thus, BITB may have therapeutic value in generating or enhancing immune function in a clinical setting.

• Journal of Microbiology and Biotechnology
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• v.16 no.7
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• pp.1097-1103
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• 2006

The divalent antibody-toxins are expected to have increased binding avidities to target cells because of the two cell-binding domains. However, previous studies showed that the refolding yield of divalent antibody-toxin is very low, and it is assumed that homodimer formation of antibody-toxin is strongly interfered by the repulsion between the two large toxin domains that come close to each other during dimer formation. In this study, B3 antibody was used as a model antibody, and its Fab domain was used to construct three different kinds of Fab divalent molecules, $[B3(Fab)-toxin]_{2}$. The monomer Fab-toxin molecules were made by fusing the Fab domain of monoclonal antibody B3 to PE38, a truncated mutant form of Pseudomonas exotoxin (PE), and a connecting sequence that contained spacer amino acid sequence (G4S)n (n=l, 2, 3) was inserted between Fab and PE38. The prepared divalent molecules were $[Fab-S\;1,\;2,\;3-PE38]_{2}\;(=[Fab-SKPCIST-KAS(G_{4}S)nGGPE-PE38]_{2}\;(n=1,\;2,\;3))$, and they are derivatives of previously studied $[Fab-H2cys-PE38]_{2}\;(=[Fab-SKPCIST-KASGGPE-PE38]_{2})$. In $[Fab-Sl,\;2,\;3-PE38]_{2}$, two Fab-S1, 2, 3-PE38 monomers were covalently linked by the disulfide bond bridge made from cysteine in the -SKPCIST- sequence. The insertion of spacer amino acids after the disulfide bridge resulted in a 12-18 fold higher yield of dimer formation than previously constructed $[Fab-Hlcys-PZ38]_{2}[7]$, 3-4-fold higher than $[Fab-ext-PZ38]_{2}[25]$. These two molecules have less amino acid spacer sequence between the disulfide bridge and PE38 domain. The design of $[Fab-PE38]_{2}$ in this study gave molecules with a higher refolding yield. The results of cytotoxicity assay showed a higher cytotoxic effect of these divalent molecules than that of the monovalent scFv-PE38 molecule.