• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.1
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• pp.76-82
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• 2010

Experiments were conducted to investigate seed persistence of Chinese milk vetch(CMV) in naturally reseeded rice field in 2007~2009. The seed and pods with seeds were buried in rice field at 0, 5 and 10 cm depths and retrieved from the field at one to three month intervals from July to the following year March and determined change of seed dormancy and viability. In the second experiment, persistence of the CMV seeds in the naturally reseeded rice field at different tillage methods and soil depths were also investigated after rice harvest in autumn. Burial depths and durations affected recovery rate, dormancy and viability of CMV seed. The viability loss was faster and greater in the seed than the pod with seeds and on the soil surface than the 5 or 10 cm burial depths. The recovery rate of CMV seed was decreased starting from one month as seed burial and it was significantly decreased to 52~65% for the seed in September. However, unlike the seed burial, the nearly 100% CMV seeds were recovered for burial as pod with seeds even after four months burial in both 0 and 5 cm depths. However, the recovery rate was sharply declined to below 30% at October in 2007 in both seed and pods with seeds and in the 2008/2009 experiment. the 15~47% of CMV seeds still remained even after October. The CMV had high seed dormancy of 95%, showing only 4~5% germination at the beginning in June but the seed germination increased to 25 to 35% in seed and 55 to 61% in pod with seeds in September due to breakage of hard seed dormancy. The viability loss was faster in the seed than in the pod with seeds regardless of depths of placement in the soil base on decayed seeds. Also the seed placed on the soil surface lost viability faster than the 5~10 burial depths. On the other hand, field observation in the naturally reseeded CMV rice field showed that as many as 917~2,185 CMV seeds $m^2$ were from the 0~15 cm soil depth in the rotary tillage and 250~10,105 CMV seeds in minimum tillage treatmints. The recovered seed germinated 25~33%, 23~43% but still had high percentage of hard seed having 64~72% and 51~77% even after rice harvest in autumn. These results indicate that freshly harvested CMV seeds had high level of primary dormancy and the dormancy was gradually broken in soil with time during rice cultivation periods and appreciable number of CMV seeds remained even 4 month after burial in soil. CMV plant regenerated naturally from the remained seed bank at rice harvest time in autumn. The CMV seedling still emerged even after 2 years of continuous destructive killing of emerged CMV plant by rotary tillage in naturally reseeded CMV plant in rice field, indicating that CMV seeds do persistent as least two years in soil.

• Clinical and Experimental Pediatrics
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• v.50 no.6
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• pp.556-564
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• 2007

Purpose : We hypothesized that the persisting bronchial hyperresponsiveness (BHR) of adolescents with asthma remission may be controlled mainly by genetic factors, and the BHR of symptomatic asthma by airway inflammation. ${\beta}_2$-adrenoceptor gene is considered to be a candidate gene in the development of BHR. Thus, ${\beta}_2$-adrenoceptor gene polymorphism may be associated with the BHR of adolescents with asthma remission, but not with the BHR of symptomatic asthma. To evaluate this hypothesis, ${\beta}_2$-adrenoceptor gene polymorphism at 2 sites (Arg16-Gly, Gln27-Glu) were examined. Methods : Two hundred two adolescents with BHR ($PC_{20}<18\;mg/mL$) and long term remission (neither asthma-related symptoms nor medication during the previous 2 years) of their asthma (remission group), 182 adolescents with symptomatic asthma (symptomatic group), and 200 healthy adolescents (control group) were studied. Asthma phenotypes were determined using methacholine bronchial provocation test and skin prick test. Genotypes of ${\beta}_2$-adrenoceptor polymorphism were evaluated by PCR-based methods. Results : Gly/Gly allele and Gly16-Gln27 haplotype were more prevalent in the remission group than in the control group (P=0.01, P=0.02), although there was no difference between the symptomatic group and the control group. In the remission group, there was significant difference in geometric mean of $PC_{20}$ among the 3 groups subdivided by the number of Gly16-Gln27 haplotype, showing that the Gly16-Gln27 haplotype was positively associated with BHR. However, no association was found between Gly16-Gln27 haplotype and BHR in the symptomatic group. Conclusion : This study demonstrates that ${\beta}_2$-adrenoceptor polymorphism at amino acid 16 and 27 was associated with BHR persisting in adolescents with asthma remission.

• Clinical and Experimental Pediatrics
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• v.51 no.2
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• pp.170-180
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• 2008

Purpose : Some antibiotics were known to exert neuroprotective effects in the animal model of hypoxic-ischemic (H-I) brain injury, but the mechanism is still unclear. A recent study reported that geneticin (G418), an aminoglycoside antibiotic, increased survival of human breast cancer cells by suppressing apoptosis. We investigated the neuroprotective effects of systemically administrated geneticin via anti-apoptosis following the H-I brain injury Methods : Seven-day-old Sprague-Dawley rat pups were subjected to unilateral (left) common carotid artery occlusion followed by 2.5 hours of hypoxic exposure and the cortical cell culture of rat brain was done under a hypoxic incubator. Apoptosis was measured in the injured hemispheres 7 days after H-I insult and in the injured cells from hypoxic chamber using morphologic analysis by Terminal dUTP Nick-end Labeling(TUNEL) assay and immunohistochemistry for caspase-3, and cytologic analysis by western blot and real time PCR for bax, bcl-2, and caspase-3. Results : The gross appearance and hematoxylin and eosin stain revealed increased brain volume in the geneticin-treated animal model of perinatal H-I brain injury. The TUNEL assay revealed decreased apoptotic cells after administration of geneticin in the cell culture model of anoxia. Immunohistochemistry showed decreased caspase-3 expression in geneticin-treated cortical cell culture. Western blot and real-time PCR showed decreased caspase-3 expression and decreased ratio of Bax/Bcl-2 expression in geneticin-treated animal model. Conclusion : Geneticin appears to exert a neuroprotective effect against perinatal H-I brain injury at least via anti-apoptosis. However, more experiments are needed in order to demonstrate the usefulness of geneticin as a preventive and rescue treatment for H-I brain injuries of neonatal brain.

• Journal of Soil and Groundwater Environment
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• v.14 no.2
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• pp.10-16
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• 2009

Characteristics of natural radioactivity were investigated for soils collected from seven sites of different bed rocks distributed in the Keum River area of Korea by the use of a Gamma-ray spectrometry. Specific activity (SA) and SA ratio (SAR) of typical naturally occurring radioactive nuclide such as $^{226}$Ra, $^{228}$Ac and $^{40}$K were determined for the soil samples. The SA values of $^{226}$Ra, $^{228}$Ac and $^{40}$K in 41 soils of 7 sites are 26.7-485 (74.2 ${\pm}$ 72.2), 30.9-157 (90.7 ${\pm}$ 32.7) and 203-1558 (990 ${\pm}$ 203) Bq/kg, respectively. The SA of $^{226}$Ra has very different values by the soils and the sites. Especially the SA of $^{226}$Ra in a soil sample of Ogcheon site is 485 Bq/kg while most SA of 41 soil samples are < 100 Bq/kg. SA of $^{228}$Ac has a little different values with the soils and sites, however the SA of $^{40}$K has almost constant values in all soil samples. The SAR values of $^{26}$Ra/$^{228}$Ac, $^{226}$Ra/$^{40}$K and $^{228}$Ac/$^{40}$K in 41 soils of 7 sites are 0.343-6.11 (0.865 ${\pm}$ 0.883), 0.0258-0.759 (0.0814 ${\pm}$ 0.1l17) and 0.0373-0.178 (0.0945 ${\pm}$ 0.0373), respectively. The SARs of $^{226}$Ra/$^{228}$Ac and $^{226}$Ra/$^{40}$K have very different values by the soils and the sites, however the SAR of $^{228}$Ac/$^{40}$K has a little difference by the soil and sites.

• Journal of Animal Science and Technology
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• v.45 no.6
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• pp.917-922
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• 2003

This study was conducted to investigate effects of farm, type of sow Landrace${\times}$Yorkshire, LY; Yorkshire${\times}$ Landrace, YL; Yorkshire${\times}$Yorkshire, YY and multi-cross bred sow, MBS), parity, farrowing year, farrowing season and mating method on reproductive traits such as total number born per litter, number of born alive per litter, number of weaned per litter, number of mummified per litter, number of stillbirth. The Reproductive Records of 3,387 litters from January, 1999 to September, 2002 were obtained from four pig farms managed by Electronic Data Processing(EDP) system. Reproductive performances for two types of F1 Sows(YL and LY) were estimated as 11.34${\pm}$0.266 and 11.57${\pm}$0.263 heads for total number of born per litter, 10.56${\pm}$0.216 and 11.81${\pm}$0.251 heads for number of born alive per litter, and 10.05${\pm}$0.131 and 9.96${\pm}$0.153 heads for number of weaned per litter, respectively. These records are significantly higher(P〈0.05) than those of YY and MBS. However, number of mummified per litter, number of stillborn per litter, number of dead by diarrhea per litter, number of dead by other reasons during lactating period per litter and estrus interval did not show significant difference between types of sows. There were more total number of born per litter and number of weaned per litter in year 2001 than other year. As year passed, number of dead by crush per litter, number of dead by diarrhea per litter and number of dead by other reasons during lactating period per litter reduced from 0.18${\pm}$0.023 to 0.07${\pm}$0.022 head, 0.12${\pm}$0.21 to 0.02${\pm}$0.020 head and 0.43${\pm}$0.041 to 0.22${\pm}$0.040 head, respectively and weaning rate increased from 0.94${\pm}$0.005% to 0.97${\pm}$0.005%. The total number of born per litter and number of born alive per litter were higher(P〈0.05) in the case of mating twice than mating once. The number of weaned per litter, number of mummified per litter and number of stillborn per litter were not significant(P〈0.05) between mating methods. Estrus interval was shorter on the occasion of twice artificial insemination(5.24${\pm}$0.153days) than twice natural mating(6.51${\pm}$0.466days).

• Journal of Chest Surgery
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• v.43 no.6
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• pp.576-587
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• 2010

Background: Effective decellularization and fixation process is critical, in order to use xenogenic valves clinically. In the present study, we decellularized bovine pericardium using sodium dodecyl sulfate (SDS) and N-lauroyl sarcosinate, treated with $\alpha$-galactosidase, and then fixed in various manners, to find out the most effective tissue preservation & fixation procedure. Material and Method: Bovine pericardium was decellularized with SDS and N-lauroyl sarcosinate, and treated with $\alpha$-galactosidase. Both groups were fixed differently, by varying glutaraldehyde (GA) or EDC (1-ethyl-3-(3-dimethyl aminopropyl)-carbodiimide)/N-hydroxysuccinamide (NHS) treatment conditions. Thereafter, physical examination, tensile strength test, thermal stability test, cytotoxicity test, pronase test, pronase-ninhydrin test, purpald test, permeability test, compliance test, H&E staining, DNA quantification, and $\alpha$-galactose staining were carried out to each groups. Result: GA fixed groups showed better physical properties and thermal stability than EDC/NHS fixed groups, EDC/NHS-GA dual fixed groups showed better physical properties and thermal stability than EDC/NHS fixed groups, and showed better thermal stability than GA fixed groups. In pronase test and pronase-ninhydrin test, GA fixed groups and EDC/NHS-GA dual fixed groups showed stronger crosslinks than EDC/NHS groups. Permeability and compliance tended to increase in EDC/NHS-GA dual fixed groups, compared to GA fixed groups. But, EDC/NHS-GA dual fixed groups had stronger tensile strength and lower cytotoxicity than GA fixed groups. Conclusion: We have verified that EDC/NHS-GA dual fixation can make effective crosslinks and lower the toxicity of GA fixation. Henceforth, we will verify if EDC/NHS-GA dual fixation can lower calcifications & tissue failure in vivo experiment.

• Applied Chemistry for Engineering
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• v.31 no.1
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• pp.43-48
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• 2020

Fe₂O₃ nanoparticles with the mixed structure of cubic and nanorod were synthesized by precipitation, hydrothermal, sol-gel method, etching process and heat treatment. Fe₂O₃/TiO₂ core-shell (CS) of type Fe₂O₃@TiO₂ composite was fabricated on a 20 nm nanolayer of TiO₂ coated on the surface of Fe₂O₃ nanoparticles. Fe₂O₃/TiO₂ yolk-shell (YS) composite was prepared by chemical etching and heat treatment of Fe₂O₃/TiO₂ CS nanoparticles. Physical properties of Fe₂O₃, Fe₂O₃@TiO₂ CS and Fe₂O₃@TiO₂ YS nanoparticles were characterized by FE-SEM, HR-TEM and X-ray diffraction. The solar reflectance, commission internationale de l'Elcairage (CIE) color coordinate and heat shield temperatures of Fe₂O₃, CS and YS type Fe₂O₃@TiO₂ pigments filled with poly acrylate (PA) paints were investigated by UV-Vis-NIR spectrometer and homemade heat shield temperature measuring device. The Fe₂O₃@TiO₂ YS red pigment filled PA composite exhibited excellent near infrared light reflecting performance and also reduced the heat shield temperature of 13 ℃ than that of Fe₂O₃ filled counterparts.

• Journal of Food Hygiene and Safety
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• v.33 no.4
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• pp.296-305
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• 2018

Spiroxamine, one of fungicides, is used to control powdery mildew in various crops and black yellow sigatoka in bananas. The major strength of spiroxamine is to control powdery mildew in various crops and bananas yellow sigatoka in bananas. The compound has shown a high level of activity, good persistence and crop tolerance. Besides powdery mildew, good control of rust, net blotch and Rhynchosporium diseases been indicated in cereals, together with a complementary activity against Septoria diseases. In 2017, the maximum residue limit (MRL) of spiroxamine established in Korea. According to Ministry of ood and rug afety) regulations, spiroxamine residues defined only parent compound. Thus, a analytical method is needed to estimate the residue level of the parent compound. The objective of this study was to develop and validate analytical method for spiroxamine in representative agricultural commodities. Samples were extracted with acetonitrile and partitioned with dichloromethane to remove the interfering substances. The analyte were quantified and confirmed liquid chromatograph-tandem mass spectrometer (LC-MS/MS) in positive-ion mode using multiple reaction monitoring (MRM). Matrix matched calibration curves were linear over the calibration ranges ($0.0005{\sim}0.1{\mu}g/mL$) for the analyte in blank extract with coefficient of determination ($r^2$) > 0.99. For validation purposes, recovery studies will be carried out at three different concentration levels (LOQ, 10LOQ, and 50LOQ) performing five replicates at each level. The recoveries 70.6~104.6% with relative standard deviations (RSDs) less than 10%. All values were consistent with the criteria ranges in the Codex guidelines (CAC/GL40, 2003) and MFDS guidelines. proposed analytical method be used as an official analytical method in the Republic of Korea.

• Journal of Life Science
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• v.28 no.7
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• pp.819-826
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• 2018

Orostachys japonicus (OJ) is a medicinal herb with immunoregulatory, anti-aging, anti-oxidative, and many other therapeutic properties. The purpose of this study was to elucidate the anti-cancer property of cultivated OJ. SW480 cell viability was significantly reduced by cumulative exposure to OJ extract. We also observed inhibitory effects of OJ after 72 hr through the growth and migration of SW480 cells using scratch assay. SW480 cells in OJ-free medium began to move into the scratch site at 24 hr; however, cells in medium containing OJ did not migrate into the scratch site until 48 hr. Male C57BL/6 mice (4 weeks old) were orally administered OJ extract for 31 days before injection of SW480 cells. At 7, 14, and 28 days after subcutaneous injection of SW480 cells, tumor weight and volume were analyzed. The body weight of the OJ-treated group was continuously increased during administration of the OJ extract relative to the control group. Injection of SW480 cells caused a reduction in body weight in all groups; however, the OJ-treated group exhibited a significant increase in body weight after 14 days. Tumor weight and volume were lower in the OJ-treated group than in the control group after 28 days. Although these results suggest that OJ suppresses the proliferation and migration of human colon cancer cells, additional studies are required to provide preclinical evidence before launching clinical trials evaluating OJ as an anti-cancer biohealth product.

• Journal of Embryo Transfer
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• v.19 no.2
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• pp.155-163
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• 2004

The aims of this study are 1) to test oocytes and embryos collected from in-vitro to achieving the valuable protocol by culturing, vitrifying and thawing of oocytes/embryos, and 2) to transfer them to recipient, and finally have resulted in pregnancies from recipient females after surgical or nonsurgical transfer. In vitro maturation and fertilization were performed according to Funahashi et al (1994). Glucose-free NCSU 23 supplemented with 5 mM sodium pyruvate, 0.5 mM sodium lactate and 4 mg/ml bovine serum albumin for 2 days at $39^{\circ}C$, and 10% fetal bovine serum albumin was added to the culture medium thereafter. Embryos were treated with 7.5 ${\mu}g/ml$ cytochalasin-B for 30 min, centrifuged at 13,000 rpm for 13 min and then exposed sequentially to an ethylene glycol(EG) vitrification solution, aspirated into OPS, and plunged/thawed into/from liquid nitrogen. In vivo embryos were surgically collected from three dornors after AI for control group. Forty-nine embryos were washed 3 times in mPBS + 10% FBS, followed treatments : cultured, centrifuged, vitrified, recovered and transferred to recipients as in vitro prepared embryos. Three recipients were transferred individually with 100, 100 frozen embryos derived from abattoir and 34 fresh embryos by surgically, and another three recipients were transferred individually with 150, 150 frozen embryos and 100 fresh embryos by nonsurgically, respectively. all recipient sows exhibited delayed returns to estrus. To our knowledge, theses results suggest that required an improved techniques, more vigorous embryos preparation and substitute to gilt with cleaner uterous condition.