• Archives of Pharmacal Research
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• v.19 no.6
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• pp.554-558
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• 1996

High-performance liquid chromatographic method was developed for the determination or LB 20304 (compound 1) in the plasma of rats and dogs. The analyte was deproteinized with 1 volume of methanol and 1/2 volume of 10% zinc sulfate, and the supernatant was injected onto a reversed-phase HPLC column. The mobile phase was a mixture of 24 parts of acetonitrile and 76 parts of 0.1% trifluoroacetic acid. The flow rate was 1 ml/min, and the effluent was monitored by fluorescence detector at an excitation wavelength of 337 nm and an emission wavelength of 460 nm. The retention time of compound 1 was 6.3 min. The assay of compound 1 was linear over the concentration range of 0.2-100.mu.g/ml in the plasma of rats and dogs. The lower limit of quantification was 0.2.mu.g/ml using 100.mu.l of plasma with a 97-99% accuracy and a 12-14% precision. In the 0.5, 5, and 50.mu.g/ml quality control samples, the intra- and inter-day accuracy were 88-95% and 88-97%, whereas intra- and interday precision were 0.5-6.6% and 0.2-9.3%, respectively, in the plasma of rats and dogs. The recoveries were 68-71% independent of concentration and species in the plasma. No interferences from endogenous substances were observed. Taken together, the above HPLC assay method by deproteinization and fluorescence detection was suitable for the determination of compound 1 in the preclinical pharmacokinetics.

• Proceedings of the KSRS Conference
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• 2009.03a
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• pp.354-359
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• 2009

Land cover types of Hustai National Park (HNP) in Mongolia, a hotspot area with rare species, were classified and their temporal changes were evaluated using Landsat MSS TM/ETM data between 1994 and 2000. Maximum likelihood classification analysis showed an overall accuracy of 88.0% and 85.0% for the 1994 and 2000 images, respectively. Kappa coefficients associated with the classification were resulted to 0.85 for 1994 and 0.82 for 2000 image. Land cover types revealed significant temporal changes in the classification maps between 1994 and 2000. The area has increased considerably by $166.5km^2$ for mountain steppe. By contrast, agricultural areas and degraded areas affected by human being activity were decreased by $46.1km^2$ and $194.8km^2$ over the six year span, respectively. These areas were replaced by mountain steppe area. Specifically, forest area was noticeably fragmented, accompanied by the decrease of $\sim400$ ha. The forest area revealed a pattern with systematic gain and loss associated with the specific phenomenon called as forest free-south slope. We discussed the potential environmental conditions responsible for the systematic pattern and addressed other biological impacts by outbreaks of forest pests and ungulates.

• Journal of Microbiology and Biotechnology
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• v.13 no.2
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• pp.282-286
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• 2003

The purpose of this study was to isolate a specific DNA probe for the strain ATTC 25611 of the species Prevotella intermedia by using a new rapid screening mothod. The whole-genomic DNA of P. intermedia ATCC 25611 was isolated and purified. The HindIII-digested genomic DNAs from the strain were cloned by the random cloning method. To screen the strain-specific DNA probe, inverted dot blot hybridization tests were performed. In this assay, 20 ng of recombinant plasmids containing the HindIII-digested genomic DNA fragment were boiled and blotted onto a nylon membrane, and hybridized with digoxigenin-dUTP labeled genomic DNAs in a concentration of 100 ng/ml. Southern blot analysis was performed in order to confirm the results of the inverted dot blot hybridization tests. The data showed that a Pi34 probe (2.1 kbp; 1 out of 32 probes) was specific for P. intermedia strain ATCC 25611 and could be useful for the detection and identification of the strain, particularly in epidemiological studies of periodontal disease.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.11
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• pp.1135-1140
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• 2006

Concentration and speciation of trihalomethanes(THMs) and haloacetic acids(HAAs) that can be created during chlorine disinfection as disinfection by-products(DBPs) in Korean water treatment plants(WTPs) were investigated. 4 WTPs that adopted conventional water treatment processes were chosen for investigation and each represented a typical WTP on the Han, Keum, Sumjin and Nakdong Rivers. The average concentration of THMs was 26.9 ppb, and the maximum and minimum concentrations were 47.6 ppb and 11.0 ppb respectively, while the average concentration of HAAs was 25.4 ppb, and the maximum and minimum concentrations were 57.1 ppb and 9.7 ppb respectively. DBPs concentration was lower in the winter than the summer. The major species of THMs was chloroform and its average percentage was 77%, and the second highest was bromodichloromethane(20%), while the concentration of bromoform was below detection limits. The sum of dichloroacetic acid(DCAA) and trichloroacetic acid(TCAA) was 97% of $HAA_5 $ on average base. But its percentage was 90% in the Han River WTP, especially it was the lowest during the winter. On the other hand, the concentration of DCAA was higher than TCAA except during the summer.

• The Plant Pathology Journal
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• v.26 no.4
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• pp.328-339
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• 2010

A tobamovirus, Ribgrass mosaic virus (RMV), was identified newly from chinese cabbage (Brassica campestris L. pekinensis) in Korea. Virus disease incidence of RMV on chinese cabbage was 37.9% in alpine area on August in 1993. RMV induced the symptoms of necrotic ring spots, necrotic streak on midrib and malformation. RMV, Ca1 and Ca3 isolate, could infect 35 species out of 45 plants including Chenopodium amaranticolor. Physical properties of RMV Ca1 isolate were very stable as 10.8 over for dilution end point, $95^{\circ}C$ for temperature inactivation point and 18 weeks for longevity in vitro. RMV had the soil transmission rate of 75.0% for the chinese cabbages, 'Chunhawang' and 'Seoul' cultivars. The purified virions of RMV had the typical ultraviolet absorption spectrum of maximum at 260 nm and minimum at 247 nm. RMV of Ca1 isolate was related serologically with antisera of Tobacco mosaic virus (TMV)-Cym, TMV-O and Pepper mottle virus, but not related with antiserum of Odontoglossum ring spot virus. coat protein gene of RMV-Ca1, sized 473 nucleotides, encoded 158 amino acid residues. Nucleotide identity of RMV-Ca1 CP gene was 96.4% with RMV-Shanghai (GenBank accession No. of AF185272) from China and 96.0% with RMV-Impatiens (GenBank accession No. of AM040974) from Germany. Identity of amino acids between RMV-Ca1 and the two RMV isolates was 96.8%. Specific three primers were selected for rapid and easy genetic detection of RMV using Virion Captured (VC)/RT-PCR method.

• Journal of Plant Biotechnology
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• v.5 no.2
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• pp.87-93
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• 2003

Brachiaria (Poaceae) is the most important forage genus for cattle production in Brazil. The genetic breeding of this genus is limited by the incompatibility among species, differences in ploidy level and the natural cloning of plants by apomixis (Valle and Miles 1992). However, plant regeneration via tissue culture methods and genetic engineering provide an opportunity to introduce new characteristics in plants of this genus. We have developed methods for the 'genetic modification of Brachiaria brizantha cv. Marandu via biolistic transformation. A higher number of shoots was obtained with 4 mg/L 2.4-diclorophenoxyacetic acid and 0.2 mg/L benzylaminopurine in calli induction medium and 0.1 mg/L naphtaleneacetic acid and 4.0 mg/L kinetin in shoot regeneration medium. A selection curve for mannose was determined to use phospho mannose isomerase (PMI) gene of Escherichia coli as a selection marker. Calli formation was inhibited from 5 g/L mannose, even in the presence of sucrose while calli that were formed in the presence of mannose failed to develop embryos showing that PMI gene can be used for selection of transformants of this grass. Different promoters were tested to evaluate the efficiency based on the detection of the GUS gene expression (Jefferson et al. 1987). The monocot promoters, act1-D and ubi-1, resulted in higher expression levels than dicot promoters, ubi-3 and act-2, or the CaMV35S and CVMV promoters.

• Parasites, Hosts and Diseases
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• v.57 no.5
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• pp.525-529
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• 2019

Blastocystis is one of the most commonly detected genera of protozoan parasites in the human intestines as well as the intestines of many other species such as pigs in several geographical regions worldwide. However, no studies have examined Blastocystis in pigs in Korea. In this study, PCR and nucleotide sequencing were performed to evaluate the genetic diversity and zoonotic potential of Blastocystis using pig fecal samples. We obtained 646 stool samples from groups of piglets, weaners, growers, finishers, and sows in Korea. A total of 390 Blastocystis-positive samples were identified, and the infection rate was 60.4%. The infection rates were significantly related to age and region. The 4 subtypes (STs) of Blastocystis confirmed by phylogenetic analysis were ST1, ST2, ST3, and ST5, indicating the high genetic diversity of Blastocystis in Korean pigs. ST5 was highly distributed in Korean pigs among detected STs in this study. Some sequences were closely related to those of Blastocystis isolated from humans. This is the first study of Blastocystis in pigs in Korea. Based on the results, Blastocystis is prevalent in Korean pigs. Although a small number of samples were obtained in some areas, the clinical development of Blastocystis infection in pigs and potential for human transmission should be further examined.

• Journal of the Semiconductor & Display Technology
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• v.18 no.4
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• pp.30-34
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• 2019

We analyzed how the features in plasma information based virtual metrology (PI-VM) for SiO₂ etching depth with variation of 5% contribute to the prediction accuracy, which is previously developed by Jang. As a single feature, the explanatory power to the process results is in the order of plasma information about electron energy distribution function (PI_EEDF), equipment, and optical emission spectroscopy (OES) features. In the procedure of stepwise variable selection (SVS), OES features are selected after PI_EEDF. Informative vector for developed PI-VM also shows relatively high correlation between OES features and etching depth. This is because the reaction rate of each chemical species that governs the etching depth can be sensitively monitored when OES features are used with PI_EEDF. Securing PI_EEDF is important for the development of virtual metrology (VM) for prediction of process results. The role of PI_EEDF as an independent feature and the ability to monitor variation of plasma thermal state can make other features in the procedure of SVS more sensitive to the process results. It is expected that fault detection and classification (FDC) can be effectively developed by using the PI-VM.

• Archives of Pharmacal Research
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• v.22 no.3
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• pp.288-293
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• 1999

Postabsorptive serum iron level was determined after oral administration of the compounds to human. In serum and whole blood, $Fe^{3+}$ was measured by ion chromatography (IC) using a pyridine-2,6-dicarboxylic acid (PDCA) as an eluent. The serum sample solutions were pretreated with I N HCI and 50% TCA. The whole blood sample solutions were treated with 3 N HCI for 30 min at $125^{\circ}C$. The limit of detection (LOD) of the IC technique is $0.2 {\mu}M$ for$Fe^{2+}$and 0.1 $\mu$M for $Fe^{3+}$. The area under concentration (AUC) can be obtained by the above analytical condition. In addition, to compare the stability of $Fe^{2+}$ to that of $Fe^{3+}$ in pharamaceutical preparations, accelerated stability test was carried out. After storing the samples under $40^{\circ}C$, 75%RH in light-resistant container for various time intervals, the contents of iron of different valencies were determined separately by the IC technique and the change and/or the interchange of among those iron species in preparations was investigated. Iron raw materials are stable, but $Fe^{2+}$ in$Fe^{3+}$ source materials was slightly converted to $Fe^{3+}$ by oxidation. $Fe^{2+}$ in$Fe^{3+}$ source raw materials and $Fe^{3+}$ in $Fe^{2+}$ raw materials are determined as impurities. Therefore, IC technique is found to be an appropriate method for comparative evaluation of dissimilar bioavailability of $Fe^{2+}$ and $Fe^{3+}$, stability of $Fe^{2+}$ and $Fe^{3+}$ raw materials and preparations.

• Animal Bioscience
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• v.34 no.11
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• pp.1766-1775
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• 2021

Objective: The oxidative stress status and changes of chicken ovary tissue after shading were studied, to determine the mechanism of the effect of shading on follicular development. Methods: Twenty healthy laying hens (40 weeks old) with uniform body weight and the same laying rate were randomly divided into two groups (the shading group and normal light group). In the shading group, the cage was covered to reduce the light intensity inside the cage to 0 without affecting ventilation or food intake. The normal lighting group received no additional treatment. After 7 days of shading, oxidative stress related indicators and gene expression were detected. Results: Analysis of paraffin and ultrathin sections showed that apoptosis of ovarian granulosa cells (GCs) increased significantly after light shading. Enzyme linked immunosorbent assay results revealed that the levels of total antioxidant capacity, malondialdehyde, superoxide dismutase (SOD), glutathione, catalase (CAT), and other substances in the sera, livers, ovaries, and follicular GCs of laying hens increased significantly after shading for 7 days; and reactive oxygen species (ROS) levels in the livers of laying hens also increased significantly. ROS in the serum, ovarian and GCs also increased. After shading for 7 days, the levels of 8-hydroxy-2 deoxyguanosine in the sera and ovarian tissues of laying hens increased significantly. Cell counting kit-8 detection showed that the proliferation activity of GCs in layer follicles decreased after shading for 7 days; the expression level of the anti-apoptotic gene B-cell lymphoma-2 in ovarian tissue and follicular GCs was significantly reduced, and the expression levels of pro-apoptotic caspase 3 (casp3), and SOD, glutathione peroxidase 2 (GPX2), and CAT were all significantly increased. Conclusion: Oxidative stress induced by shading light has a serious inhibitory effect on follicular development during reproduction in laying hens.