• The Korea Journal of Herbology
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• v.22 no.2
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• pp.13-16
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• 2007

Objectives : Palmul-tang(Bawu-tang) has been traditionally prescribed a medicine as a restorative. Methods : In this study, we investigated the acute toxicity about water-extracted PalMul-tang(Bawu-tang). Twenty-five mice completed 14 days of oral Palmul-tang(Bawu-tang) at the respective doses of 0(control group), 2560, 3200, 4000 and 5000mg/kg. Results : We observed survival rates, general toxicity, change of body weight, and autopsy. Conclusions : To be confirmed the data for the toxicity and safety problems of oriental medicine prescription. Compared with the control group, we could not find any toxic alteration in all treated groups (2560, 3200, 4000 and 5000mg/kg). In conclusion, LD50 of Palmul-tang(Bawu-tang) was over 5000mg/kg and it is very safe to ICR mice.

• The Korea Journal of Herbology
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• v.22 no.4
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• pp.59-64
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• 2007

Objectives : Palmultang(Bawu-tang) has been traditionally prescribed as a restorative, The present study was undertaken to determine the possible toxic effects of Palmultang on SD rats. Methods : In this study, we investigated the subacute toxicity of water-extracted Palmultang(Bawu-tang) on SD rats. Twenty rats were orally adiministered Palmultang for 28 days at a dose of 0 mg/kg(control group) or 1500 mg/kg(treated group), respectively. Results : All of subjects was survived. No significant difference in abnormal clinical signs, related to hematological values, serum biochemical values, water and feed intake, coagulation time, autopsy analysis, organ weight, tissue microscopically, funduscopy, urine intake and urinalysis, was detected. Conclusions : Compared with the control group, we could not find any subacute toxic alteration in treated group (1500 mg/kg) for 28 days. This result suggests that Palmultang, a herbal medicine prescription, is a safe prescription to body.

• BMB Reports
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• v.45 no.8
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• pp.452-457
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• 2012

Diketoreductase (DKR) from Acinetobacter baylyi contains two tryptophan residues at positions 149 and 222. Trp-149 and Trp-222 are located along the entry path of substrate into active site and at the dimer interface of DKR, respectively. Single and double substitutions of these positions were generated to probe the roles of tryptophan residues. After replacing Trp with Ala and Phe, biochemical and biophysical characteristics of the mutants were thoroughly investigated. Enzyme activity and substrate binding affinity of W149A and W149F were remarkably decreased, suggesting that Trp-149 regulates the position of substrate at the binding site. Meanwhile, enzyme activity of W222F was increased by 1.7-fold while W222A was completely inactive. In addition to lower thermostability of Trp-222 mutants, molecular modeling of the mutants revealed that Trp-222 is vital to protein folding and dimerization of the enzyme.

• BMB Reports
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• v.37 no.3
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• pp.356-361
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• 2004

To develop a simplified method that can rapidly prepare DNA microarray probes in a massive scale, a lambda phage genomic DNA-fragments library was constructed for the microarray-probes collection. Four methods of DNA band recovery from the first PCR products were tested and compared. The DNA microarray probes were collected by a novel method of nested PCR that was mediated by gel isolation of the first PCR products. This method was named GIN-PCR. The probes that were prepared by this GIN-PCR technique were used as subjects to fabricate a DNA microarray. The results showed that a wooden toothpick was superior to the other 3 methods, since this technique can steadily transfer the DNA bands as the template of the second PCR after the first PCR. A group of probes were successfully collected and DNA microarrays were constructed using these probes. Hybridization results demonstrated that this technique of DNA recovery and probe preparation was rapid, efficient, and effective. We developed a cost-effective and less labor-intensive method for DNA microarray probe preparation by nested PCR that is mediated by wooden toothpick transfer of the DNA bands in the gel after electrophoresis.

• Journal of Sasang Constitutional Medicine
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• v.22 no.3
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• pp.132-140
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• 2010

1. Objective: To compare the contents and transfer rate of hazardous substances in crude, washing solution, crude after washing, decoction and remnant after boiling. 2. Methods: The heavy metal contents of each step were measured by inductively coupled plasma mass spectrometer (ICP-MS) and mercury analyzer (MA-2). In order to analyze pesticides in each sample we used simultaneous multi-residue analysis of pesticides by GC/ECD, which was followed by GC/MSD analysis to confirm the identity of the detected pesticide in each sample. In addition, the contents of sulfur dioxide (SO2) were performed by Monier-Williams distillation method. 3. Results: 1) Contents (mg/kg) of heavy metals in decoction of all herbal medicine prescriptions were not detected. 2) Transfer rates (%) of heavy metals from crude to remnant were As (83.3%), Cd (100.0%), Pb (182.6%) and Hg (100.0%). 3) Contents (mg/kg) of residual pesticides were not detected. 4) Transfer rate (%) of sulfur dioxide (SO2) from crude to remnant was 44.2%. 4. Conclusion: Our results showed that boiled herbal medicine prescriptions which we take is safe from the hazardous substances.

• Herbal Formula Science
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• v.15 no.2
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• pp.119-126
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• 2007

Objectives: This study presents observation of microorganism such as total aerobic bacteria, total fungus, E. coli, Pseudonomas aerugjnosa, Staphylococcus aureus, and Salmonella typhimurium in herbal decoction manufactured by Korean medical clinic. Methods: We examined to observe microorganism using the requirements for the experimental methods recommended by FDA. For the identification, we observed microscopic methods and carried out polymerase chain reaction (PCR) and DNA purification. The purified DNA samples were analyzed by DNA sequencer. As compared with NCBI database. the results were identified by sequences similarity. Results and conclusion: 26 (55%) of 46 decoctions observed positive for microbial test. 12 (46 %) of 26 positive decoctions exceed requirement of microbial limit test. These microbial colony identified genus of Bacillus using microscopic and DNA sequencing methods.

• Journal of Microbiology and Biotechnology
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• v.24 no.8
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• pp.1059-1064
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• 2014

Staphylococcus aureus is a major human pathogen, implicated in both community and hospital acquired infections. The therapy for methicillin-resistant Staphylococcus aureus (MRSA) infections is becoming more difficult because of multidrug resistance and strong biofilm-forming properties. Schiff bases have attracted attention as promising antibacterial agents. In this study, we investigated the in vitro activity of taurine-5-bromosalicylaldehyde Schiff base (TBSSB) against MRSA. The minimum inhibitory concentrations (MIC) and minimum bactericidal concentration (MBC) were determined using a microtiter broth dilution method. TBSSB effectively inhibited planktonic MRSA, with an MIC of $32{\mu}g/ml$. The time-kill curve confirmed that TBSSB exhibited bactericidal activity against MRSA. TBSSB was also found to significantly inhibit MRSA biofilm formation at 24 h, especially at $1{\times}MIC$ and sub-MIC levels. Furthermore, scanning electron microscopy and transmission electron microscopy showed remarkable morphological and ultrastructural changes on the MRSA cell surface, due to exposure to TBSSB. This study indicated that TBSSB may be an effective bactericidal agent against MRSA.

• Geomechanics and Engineering
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• v.15 no.2
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• pp.775-781
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• 2018

Shake table tests were conducted on scaled tunnel model to investigate the mechanism and effect of seismic loadings on horseshoe scaled tunnel model in ground fissure site. Key technical details of the experimental test were set up, including similarity relations, boundary conditions, sensor layout, modelling methods were presented. Synthetic waves and El Centro waves were adopted as the input earthquake waves. Results measured from hanging wall and foot wall were compared and analyzed. It is found that the seismic loadings increased the subsidence of hanging wall and lead to the appearance and propagation of cracks. The values of acceleration, earth pressure and strain were greater in the hanging wall than those in the foot wall. The tunnel exhibited the greatest earth pressure on right and left arches, however, the earth pressure on the crown of arch is the second largest and the inverted arch has the least earth pressure in the same tunnel section. Therefore, the effect of the hanging wall on the seismic performance of metro tunnel in earth fissure ground should be considered in the seismic design.

• Journal of Power Electronics
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• v.14 no.6
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• pp.1147-1156
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• 2014

This study proposes a quasi-fixed-frequency hysteresis current tracking control strategy for modular multilevel converters (MMCs) on the basis of voltage partition principle. First, by monitoring the grid voltage and the deviation between the output and reference currents, the output voltage is determined, thus prompting the output current to quickly and efficiently track the given current. Second, the voltages of the upper/lower capacitor of the arm and the voltages between the upper and lower arms are balanced by combining these arms with virtual loop mapping and arm voltage balance control, respectively. In particular, the proposed method is designed for any level and number of sub-modules. The validity of the proposed method is verified by simulations and experimental results of a five-level MMC prototype.

• Journal of Sasang Constitutional Medicine
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• v.22 no.2
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• pp.101-107
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• 2010

1. Objectives: The aim of this study is to investigate the acute toxicity and safety of Taeeumjowi-tang. 2. Methods: We investigated the acute toxicity for water-extracted Taeeumjowi-tang. 25 male and 25 female mice were observed for 14 days after one day oral administration of Taeeumjowi-tang at the respective doses of 0(control group), 2560, 3200, 4000 and 5000 mg/kg. 3. Results: We observed survival rates, general toxicity, change of body weight and autopsy. 4. Conclusions: The data confirmed that Taeeumjowi-tang is free from the toxicity and safety problems in oral route respectively. Compared with the control group, we could not find any toxic alteration in all treated groups(2560, 3200, 4000 and 5000 mg/kg). In conclusion, LD50 of Taeeumjowi-tang was over 5000 mg/kg and it is very safe to mice.