• Restorative Dentistry and Endodontics
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• v.33 no.4
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• pp.332-340
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• 2008

The purpose of this study was to evaluate the viability of periodontal ligament cell in rat teeth using slow cryopreservation method with magnetic field through MTT assay and TUNEL test. For each group, 12 teeth of 4 weeks old white female Sprague-Dawley rat were used for MTT assay, and 6 teeth in TUNEL test. The Maxillary left and right, first and second molars were extracted as atraumatically as possible under tiletamine anesthesia. The experimental groups were group1 (immediately extraction), group 2 (cold preservation at 4$^{\circ}C$ for 1 week), group 3 (rapid cryopreservation in liquid nitrogen), group 4 (slow cryopreservation with magnetic field of 1 G), and group 5 (slow cryopreservation). F medium was used as preservation medium and 10% DMSO as cryoprotectant. After preservation and thawing, the MTT assay and TUNEL test were processed. One way ANOVA and Scheffe method were performed at the 95% level of confidence. The value of optical density obtained after MTT analysis was divided by the value of eosin staining for tissue volume standardization. In both MTT assay and TUNEL test, it had showed no significant difference among group 3, 4, and 5. And group 3 had showed higher viability of periodontal ligament cell than group 2. From this study, slow cryopreservation method with magnetic field can be used as one of cryopreservation methods.

• Journal of the Korean Institute of Landscape Architecture
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• v.45 no.2
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• pp.51-59
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• 2017

This study evaluated the drought tolerance of Liriope platyphylla F.T.Wang & T.Tang, Dendranthema zawadskii var. lucidum (Nakai) J.H.Park, Hosta longipes (Franch. & Sav.) Matsum., Sedum sarmentosum Bunge and Zoysia japonica Steud. for an extensive green roof. In order to assess drought tolerance of green roof plants, several criteria were measured such as volumetric water content, leaf and soil moisture potential, chlorophyll a and b, chlorophyll fluorescence, photosynthesis, stomatal conductance, transpiration rate and antioxidants. The results of the drought tolerance measurement of green roof plants focused on the gradually withering of plants from lack of volumetric water content. D. zawadskii was the first to show an initial wilting point, followed by Z. japonica, H. longipes and L. platyphylla in order while S. sarmentosum showed no withering. It was concluded that H. longipes, L. platyphylla and S. sarmentosum were highly drought tolerant plants able to survive over three weeks. Furthermore, chlorophyll a and b were divided into two types: Type I, which kept regular content from the beginning to the middle of the period and suddenly declined, like H. longipes and Z. japonica; and Type II, which showed low content at the beginning, sharply increased at the middle stage and decreased, like D. zawadskii, L. platyphylla and S. sarmentosum. Volumetric water content and the amount of evapotranspiration consistently declined in all plant species. The analysis of chlorophyll fluorescence results that S. sarmentosum, which had relatively high drought tolerance, was the last to decline, while Z. japonica and S. sarmentosum withered after rapid reduction. At first, photosynthesis, stomatal conductance and transpiration rate showed high activity, but they lowered as the plant body closed stomata owing to the decrease in volumetric water content. Measuring antioxidants showed that when drought stress increased, the amount of antioxidants grew as well. However, when high moisture stress was maintained, this compound was continuously consumed. Therefore, the variation of antioxidants was considered possible for use as one of the indicators of drought tolerance evaluation.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.2
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• pp.127-138
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• 2000

To enable rapid and convenient soil test, new soil analytical methods, which require only one instrument, UV/Vis spectrophotometer, were developed and named "Soiltek KA-P spectrophotometric methods". The Soiltek$^{(R)}$ KA-P spectrophotometric method was compared with standard method of RDA in analytical capability for soil chemical properties. Using the 78 soils collected from upland, paddy, orchard, and vinyl house soils, soil organic matter, exchangeable K, Ca, and Mg. CEC, available $SiO_2$, and nitrate were analyzed by the two methods. The color stability(ratio of the absorbance at elapsed time t to the absorbance at time t=0) of organic matter. Ca, Mg, and available $SiO_2$ decreased to about 2% within one hour. However, that of exchangeable K, CEC, and nitrate remained constant. The results obtained with Soiltek$^{(R)}$ KA-P spectrophotometric method showed highly significant correlation with those measured by the standard method of RDA($R^2$ >0.9501), in which the slopes were near unity of $1.0{\pm}0.05$. The standard deviation values of organic matter, exchangeable K, Ca, and Mg, CEC, available $SiO_2$, and nitrate were apparently lower than ${\pm}1.8gkg^{-1}$, ${\pm}0.05cmol^+kg^{-1}$, ${\pm}0.18cmol^+kg^{-1}$, and ${\pm}0.13cmol^+kg^{-1}$, ${\pm}1.0cmol^+kg^{-1}$, ${\pm}5.0mgkg^{-1}$, and ${\pm}10.0mgkg^{-1}$, respectively. All the measurements showed coefficients of variation of less than 7~17% and were within the confidence level of 95%, which means both the methods are precise. Considering the relative simplicity, low cost, precision and accuracy, the proposed Soiltek$^{(R)}$ KA-P spectrophotometric methods could be recommended as an alternative to standard method.

• Pediatric Infection and Vaccine
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• v.18 no.2
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• pp.193-200
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• 2011

Purpose : The effect of corticosteroid on severe pneumonia caused by 2009 pandemic influenza (H1N1) A virus is controversial. This study was aimed to present the effects of early, short-term corticosteroid treatment for severe pneumonia with this virus infection. Methods : A retrospective analysis was performed on severe pneumonia patients (37 patients) who had severe respiratory distress at presentation requiring oxygen therapy and received intravenous methylprednisolone (MP, 8-10 mg/kg, divided in 4 doses/day for 2-3 days) with oseltamivir. The clinical and laboratory characteristics of the patients were evaluated through the medical records and chest radiographic findings. Results : The mean age and male-to-female ratio of the patients were 6.5${\pm}$2.9 years of age, and 3.4:1 (male 29 patients), respectively. The 5-9 aged group was predominant among the age groups (25 patients, 67.6%). Duration of fever prior to admission was 1.4${\pm}$0.6 days and dyspnea developed within 24 h after beginning of respiratory symptoms in all patients. All patients were previously healthy and received oseltamivir within 48 h. Thirteen patients (35.1%) developed dyspnea during oseltamivir treatment. Following MP infusion, all 37 patients including 13 progressive pneumonia patients during oseltamivir treatment showed an immediate halt in the progression of pneumonic infiltration with rapid clinical improvement. There were no side-effects following steroid use. Conclusion : For severe pneumonia patients, early corticosteroid treatment halted clinical exacerbation, and possibly prevented progression to acute respiratory distress syndrome. Further controlled clinical studies are needed for the role of corticosteroids and antivirals on severely affected patients with influenza virus infections.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.18 no.4
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• pp.214-226
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• 2013

To understand the changing patterns in phytoplankton communities, we conducted 12 surveys along the Nakdong River, its estuary, and adjacent coastal areas between January 2011 and October 2012 (during the period of barrage construction and sediment dredging). Monthly precipitation ranged from 0 to 502 mm during the survey period, and salinity ranged between 0.1 psu and 0.3 psu in the Nakdong River, regardless of the depth, indicating no seawater influence, while salinity showed large seasonal fluctuations in the estuarine and coastal station, ranging from 0.1 psu to 34.8 psu. A total of 402 phytoplankton species were identified, 178 species from the river and 331 species from the estuary and coastal areas. Phytoplankton standing crop increased in 2012 compared to that in 2011, and was found to be highest in the river, followed by the estuary and coastal areas. Among the top 20 species in frequency of occurrence and dominance, Stephanodiscus spp., Aulacoseira granulata, and Aulacoseira granulata var. angustissima and Pseudo-nitzschia spp. were important species along the river-estuary-coastal areas. Diatoms were the major taxonomic group inhabiting the Nakdong river-estuary-coastal areas. A comparison of seasonal dominant phytoplankton species revealed a slight decrease over the years, from 13 species in 2011 to 10 species in 2012. However, no significant difference was found in the diversity of phytoplankton species between the two survey years, although lightly greater diversity was observed in the coastal areas than in the river and estuary. Cluster analysis with community composition data revealed that the community structure varied significantly in 2011 depending on the time of survey, while in 2012, it hardly showed any variation and was simpler. An increase in the phytoplankton standing crop, fewer dominant species, and simpler community structure in 2012 compared to those in 2011 are probably due to the rapid environmental changes along the Nakdong River. To investigate these ecological relationships, it is necessary to conduct further studies focusing on integrated analyses of biocenosis, including phytoplankton with respect to the changes in nutrient distribution, variation of freshwater discharge, and effect area of freshwater in the Nakdong estuary and adjacent coastal areas.

• Korean Journal of Environmental Biology
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• v.35 no.4
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• pp.694-705
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• 2017

The aim of this study was to isolate and identify marine bacterium with anti-methicillin-resistant Staphylococcus aureus (MRSA) activity, and to purify the anti-MRSA compound, as well as to determine its activity and synergistic effects. Among the marine bacteria isolated in this study, the YJ-1 isolate had the strongest anti-MRSA activity. The YJ-1 isolate was identified on the basis of its biochemical characteristics and an analysis of 16S rRNA gene sequences. The YJ-1 isolate showed over 99.2% homology with Pseudomonas stutzeri, and was designated as a Pseudomonas sp. YJ-1. The optimal culture conditions were $25^{\circ}C$ and initial pH 7.0. For the purification of the anti-MRSA compounds, the YJ-1 was cultured in Pa PES-II medium, and the culture filtrates were extracted by ethyl acetate, hexane, and 80% MeOH. The 80% MeOH fraction was separated by a $C_{18}$ ODS column, silica gel chromatography and a reverse phase HPLC, to yield three anti-MRSA agents, the MR1, MR2, and MR3 compounds. When the MR1 compound of $250{\mu}g\;mL^{-1}$ concentration was applied to the MRSA cells, over 95% of bacterial cells was killed within 48 hr. Compared with vancomycin and ampicillin, the MR1 compound showed significant anti-MRSA activity. In addition, the anti-MRSA activity was increased by dose and time dependent manners. Furthermore, the combination of an MR1 compound with vancomycin produced a more rapid decrease in the MRSA cells than did the MR1 compound alone. Taken together, our results suggest that the Pseudomonas sp. YJ-1 and its anti-MRSA compounds could be employed as a natural antibacterial agent in MRSA infections.

• Journal of agriculture & life science
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• v.46 no.1
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• pp.91-103
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• 2012

The aim of this study was to develop a rapid and cheap bioassay of four lignans (schisandrin, schisandrin C, the gomisin A and gomisin N) isolated from Schizandra chinensis Baill on seed germination and seedling growth of the radish. Its structure was determined by analysis of MS and NMR spectroscopic data. Radish seeds immersed for 1 hr in the solutions of $10^{-5}M$, $10^{-6}M$ and $10^{-7}M$ of schisandrin, schisandrin C, gomisin A, and gomisin N, seed germination was observed with in 60 hr after all of the treatments. Also, the seeds were germinated faster compared to untreated controls. At early germination stage, 48 hr after the treatment of the lignans, the suppression of germination was observed from all treatments; the suppression due to schisandrin and gomisin A was the highest at the concentration of $10^{-6}M$. The level of suppression increased as the concentration increased in the treatment of schisandrin C and gomisin N. Percent germination of seed after 184 hr was increased 90% at all treatments. For the effects of lignan treatment on seedling growth in radish, the growth of hypocotyl was promoted by gomisin A and gomisin N at all concentrations. Root elongation was significantly promoted by schisandrin and gomisin N at $10^{-5}M$ and $10^{-6}M$, respectively. Fresh and dry weights of the seedlings were high at a low concentration of $10^{-7}M$, but significantly reduced by schisandrin C at a high concentration of $10^{-5}M$. The results of the germination activity and seedling growth of the lignans from S. chinensis suggest their potential use as natural growth regulators.

• Food Science and Preservation
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• v.25 no.1
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• pp.44-51
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• 2018

The purpose of this study is to present the results as basic data for establishing proper storage conditions and distribution conditions of actual farms at point of increasing concern about hygiene and palatabiltiy of consumers to food. In this study, three farmhouses of dried persimmons prepared using different storage conditions were selected in Sangju (Korea). The dried persimmons were stored for 90 days. Changes in temperature and humidity were measured with a temperature and humidity recorder under each storage condition, and physicochemical analysis and sensory evaluation were performed. The average temperatures of farmhouse A, B and C were approximately $-22--23^{\circ}C$, $-19--18^{\circ}C$ and $-25^{\circ}C$ respectively. The humidities of A, B and C were 62-63%, 59-60%, and 66-67%, respectively, and the moisture contents of all farmhouses increased during the storage period, with farmhouse B showing the most rapid increase. Free sugars increased, except for those from farmhouse C. Persimmons from farmhouse B showed the greatest changes in chewiness and hardness. The values of $a^*$ and $b^*$ were significantly decreased in persimmons from farmhouse B, and the color difference value of farmhouse B was dramatically increased. Sensory evaluation showed that the color preference tended to decrease compared with the initial value. Only farmhouse B showed decreased overall acceptability. Moreover, farmhouse B had the highest storage temperature and lowest humidity. Therefore, our results showed that storage at a low temperature and high humidity was important for manufacturing high-quality dried persimmons.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.6
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• pp.968-974
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• 2010

We assessed the feasibility of discrete wavelet transform (DWT) applied for the spectral processing to enhance the estimation performance quality of soil organic matters using visible-near infrared spectra and mapped their distribution via block Kriging model. Continuum-removal and $1^{st}$ derivative transform as well as Haar and Daubechies DWT were used to enhance spectral variation in terms of soil organic matter contents and those spectra were put into the PLSR (Partial Least Squares Regression) model. Estimation results using raw reflectance and transformed spectra showed similar quality with $R^2$ > 0.6 and RPD> 1.5. These values mean the approximation prediction on soil organic matter contents. The poor performance of estimation using DWT spectra might be caused by coarser approximation of DWT which not enough to express spectral variation based on soil organic matter contents. The distribution maps of soil organic matter were drawn via a spatial information model, Kriging. Organic contents of soil samples made Gaussian distribution centered at around 20 g $kg^{-1}$ and the values in the map were distributed with similar patterns. The estimated organic matter contents had similar distribution to the measured values even though some parts of estimated value map showed slightly higher. If the estimation quality is improved more, estimation model and mapping using spectroscopy may be applied in global soil mapping, soil classification, and remote sensing data analysis as a rapid and cost-effective method.

• The Korean Journal of Blood Transfusion
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• v.29 no.3
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• pp.262-272
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• 2018

Background: Massive hemorrhage due to trauma is one of the major causes of death in trauma patients, and the quick supply of appropriate blood products is critical in order to reduce the mortality rate. We introduced a massive transfusion protocol (MTP) for safe and rapid transfusion of trauma patients. Using records collected since its adoption, we compared the characteristics of MTP applied group (MTP group) and MTP not applied group (non-MTP group) to determine whether there is an indicator for predicting patients to be treated with MTP. Methods: We retrospectively reviewed the electronic medical records and laboratory findings of patients who received massive transfusions in the trauma emergency room of a single tertiary hospital from February to August 2018. We analyzed various laboratory test results, the amount and ratio of the transfused blood products, and the time required for blood products to be released for the MTP group and the non-MTP group. Results: Of the 54 trauma patients who received massive transfusions, 31 were in the MTP group and 22 in the non-MTP group. There was no significant difference in initial vital signs (except blood pressure) and laboratory test results. Also there was no difference in the amount and ratio of blood products, but the time required for blood product release was shorter in the MTP group. Conclusion: There was no significant difference in clinical findings such as initial vital signs and laboratory test results between the MTP and non-MTP groups, but required blood products were prepared and released more quickly for the MTP group.