• Bulletin of the Korean Chemical Society
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• v.33 no.8
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• pp.2731-2736
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• 2012

The use of pyrimethamine as antibacterial drug is limited by the poor solubility. To enhance its solubility, we prepared complexes of pyrimethamine with low-molecular-weight succinoglycan isolated from Sinorhizobium meliloti. Low-molecular-weight succinoglycans are monomers, dimers, and trimers of the succinoglycan repeating unit. The monomers and dimers were separated into their three species (M1, M2, and M3) and four fractions (D1 to D4) using chromatographic techniques, which were shown to be nontoxic. The solubility of pyrimethamine was markedly increased up to 42 fold by succinoglycan D3, where the level of its solubility enhancement was even 8-20 fold higher comparing with cyclodextrin or its derivatives. The complex formation of succinoglycan D3 with pyrimethamine was confirmed by $^1H$ nuclear magnetic resonance spectroscopy, Fourier-transform infrared spectroscopy, differential scanning calorimetry, scanning electron microscopy, and molecular modeling studies. Herein, we suggest that the low-molecular-weight succinoglycans may be utilized as highly effective solubilizers of pyrimethamine for pharmaceutical purposes.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.28-28
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• 2009

Fabrications of antireflection structures on solar cell were investigated to trap the light and to improve quantum efficiency. Introductions of patterned substrate or textured layer for Si solar cell were performed to prevent reflectance and to increase the path length of incoming light. However, it is difficult to deposit conformally flat electrode on perpendicular plane. ZnO is II-VI compound semiconductor and well-known wide band-gap material. It has similar electrical and optical properties as ITO, but it is nontoxic and stable. In this study, Al-doped ZnO thin films are deposited as transparent electrode by atomic layer deposition method to coat on Si substrate with micro-scale structures. The deposited AZO layer is flatted on horizontal plane as well as perpendicular one with conformal 200 nm thickness. The carrier concentration, mobility and resistivity of deposited AZO thin film on glass substrate were measured $1.4\times10^{20}cm^{-3}$, $93.3cm^2/Vs$, $4.732\times10^{-4}{\Omega}cm$ with high transmittance over 80%. The AZO films were coated with polyimide and performed selective polyimide stripping on head of column by reactive ion etching to measure resistance along columns surface. Current between the micro-columns flows onto the perpendicular plane of deposited AZO film with low resistance.

• Research in Plant Disease
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• v.9 no.2
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• pp.57-63
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• 2003

Clubroot disease of curcifer crops caused by Plasmodiophora brassicae had been first reported in 1928 in Korea, and maintained mild occurrence until 1980s. Since 1990s the disease has become severe in alpine areas of Kyonggi and Kangwon, gradually spread to plain fields throughout the country, and remains as the great-est limiting factor for its production. Researches on the disease has begun in late 1990s after experiencing severe epidemics. Survey of occurrence and etiological studies have been carried out, particularly, on the pathogen physiology, race identification, quantification of soil pathogen population, and host spectrum of the pathogen. Ecology of gall formation and its decay, yield loss assessment associated with time of infection, and relationships between crop rotation and the disease incidence was also studied during late 1990s. In studies of its control, more than 200 crucifer cultivars were evaluated for their resistance to the disease. Lime applica-tion to field soil was also attempted to reduce the disease incidence. Resistant radish and welsh onion were recommended as rotation crops with crucifers after 3-year field experiments. However, so for, most studies on clubroot disease in Korea have been focused on chemical control. Two fungicides, fluazinam and flusulfamide, were selected and extensively studied on their application technologies and combination effects with lime application or other soil treatment. To develop environmentally-friendly control methods, solar-disinfection of soil, phosphoric acid as a nontoxic compound, and root-parasiting endophytes as biocontrol agents were examined for their effects on the disease in fields. In the future, more researches are needed to be done on development of resistant varieties effective to several races of the pathogen, establishment of economically-sound crop rotation system, and improvement of soil-disinfection technique applicable to Korean field condi-tion, and development of methodology of pretreatment of fungicides onto seeds and seedbeds.

• Economic and Environmental Geology
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• v.37 no.4
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• pp.383-389
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• 2004

Understanding flow pattern of water and solute in subsurface is essential for the reduction and prevention of contamination of soil and groundwater and for the investigation and remediation of contaminated site. The objective of this study is to examine the infiltration pattern in a soil developed from the Jurassic granite using (Brilliant Blue FCF $C_{37}H_{34}N_{2}Na_{2}O_{9}S_{3}$), the nonfluorescent and nontoxic food dye. All image processing was conducted using geographic image processing software, ER Mapper, Version 6.2. The dye coverage was determined by counting the stained pixels in the photographs (80${\times}$80cm, 80TEX>${\times}$5cm) for the vertical and horizontal view. A homogeneous matrix flow occurred in the A horizon with weak, medium granular structure and fingering at the interface of finer-textured A horizon and coarser-textured C horizon. Pegmatitic vein originated from the granite and plant root in C horizon induced preferential flow.

• Korean Journal of Organic Agriculture
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• v.26 no.3
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• pp.501-514
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• 2018

Taraxacum hallaisanense (pr), a species of the family Compositae is a perennial herb plants that inhabit to Jeju Island. In the study, we performed to determine the anti-inflammatory effects in LPS-induced RAW 264.7 cells and antioxidant activity of ethanol extracts from T. hallaisanense whole plants. The antioxidant activity of extracts was measured by contents of polyphenol and flavonoid, DPPH radical scavenging, and reducing power activity. The anti-inflammatory effect of T. hallaisanense extracts was measured by NO and $IL-1{\beta}$ production inhibitory activity and the expression of pro-inflammatory in lipopolysaccharide (LPS)-induced Raw 264.7 cells. Also, the expression of pro-inflammatory genes such as iNOS, COX-2 and NF-kB protein were reduced. In the cytotoxicity measurement by cytotoxicity kit, the extract was exhibited Raw 264.7 cell viabilities as nontoxic result in concentration of $25{\sim}400{\mu}g/ml$. These results indicated that ethanol extracts of T. hallaisanense whole plants expected development possibility as nutrial additives through high anti-inflammatory effects and antioxidant activity.

• Journal of environmental and Sanitary engineering
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• v.15 no.3
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• pp.88-93
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• 2000

The objective of this study was to depict the kinetic behavior of the platinum catalyst for the deep oxidation of VOCs and their mixture. The oxidation characteristics of VOCs, which were benzene, toluene, and styrene, was studies on a 0.5% $Pt/{\gamma}-Al_2O_3$ catalyst. The reactivity increases in order benzene>toluene>styrene. In mixtures, remarkable effects on reaction rate and selectivity have been evident ; the strongest inhibiting effect was shown by styrene and increases in a reverse order with respect to that of reactivity. The reaction model reveals that there is a competition between the two reactants for the oxidized catalyst. Thus, the nontoxic catalytic oxidation process was suggested as the new VOCs control technology.

• The Korean Journal of Nuclear Medicine
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• v.4 no.1
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• pp.43-49
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• 1970

In recent years with development of immuno-electrophoresis, more acurate analysis of the serum protein became possible. However, there is few reports in the literature which investigated the changes of the immunoglobulin compared with electrophoretically fractioned serum thyroglobulin in the patients with various thyroid diseases. The purpose of this report is to investigate the changes of thyroglobulin in various thyroid diseases by the method of immuno-electrophoresis and to compare the results with.serum protein fractionated by the method of agar-gel micro-electrophoresis. Materials and Methods: Sera from 9 patients with diffuse toxic goiter, 2 nodular nontoxic goiter, 2 thyroiditis, 3 hypothy, roidism, 1 thyroid cancer, 7 cystic degeneration of the thyroid gland, and 10 normal subject were taken. All cases were confirmed by various laboratory thyroid function tests and thyroid needle biopsy. Immuno-electrophoretic analysis of the serum were performed by Scheidegger's modified micro-immuno-electrophoretic method. The antiserum was obtained from the Travenol Laboratories International, Hyland Products Division and was rabbit anti-human thyroglobulin. Microscope slide agar-gel electrophoresis for serum protein fractionation was performed at $4^{\circ}C$ using veronal buffer, pH 8.6 and ionic strength 0.05, with 54 volts and 2.8 mA for 60 minutes. The fractionated slide was stained with 0.1% thiazine red. The results were as follows: 1) Increase of immune-globulin macroglobulin (IgM), alphaglobulin, and immune-globulin A (IgA) by 95.8%, 100%, 29.2% respectively was found in the serum from various thyroid diseases. 2) Thyroglobulin fraction was found to be increased in 50%, no change in 41.7%, and no line in 8.3% with all of the various goiter patients. On the other hand, 10 normal control group showed only 2 cases of increase, 5 cases of no change and 3 cases of no line.

• Toxicological Research
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• v.22 no.2
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• pp.95-102
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• 2006

Exposure to soluble nickel compound produces toxic effects on immune system, but the mechanism of action remains to be elucidated. Differential gene expression was studied to understand the potential molecular mechanism responsible for acute toxicity induced by nickel acetate in spleen cells. We exposed mouse spleen cells to nickel acetate with a nontoxic dose ($40{\mu}M$) and then extracted total RNA at 6 h and 12 h after exposure. The RNA was hybridized onto 10K mouse oligonucleotide microarrays, and data were analyzed using GeneSpring 7.1. Nickel had a modest effects on expression of many genes, in the range of 1.3-3 fold. The expression profile showed time-dependent changes in expression levels of differentially expressed genes, including some important genes related to cell cycle, apoptosis and DNA repair. In hierarchical cluster analysis of duplicate experiments, 111 genes were screened out. Out of these, 44 genes showing time- dependent up-regulation (>1.5 fold) and 38 genes showing down-regulation (>1.5 fold) at all time points were chosen for further analysis. The change in the expression of three genes (GPX1, GADD45B and FAIM) after nickel treatment was validated using RT-PCR. As a rule, a number of genes appear to be coordinately regulated between cell survival and cell death from nickel toxicity. In conclusion, changes in the gene profile in the spleen after nickel treatment are complex and genes with diverse functions are modulated. These findings will be contributed to the understanding of the complicated biological effects of nickel.

• Applied Microscopy
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• v.31 no.4
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• pp.385-392
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• 2001

The purpose of this study was to evaluate the histological toxicity of chitosanoligosaccharide on the rat. A healthy male of Wistar rat that weighted $250{\pm}350g$ was used for experiment The experimental group was divided into five groups. Group 1 was control group which treated with general food Group 2 was $F_1$ generation which was born by mating of 0.1% (1 mg/ml) chitosanoligosaccharide was supplied by feeding ad libitum for 30 days. Group 3 was $F_2$ generation which was born by mating $F_1$ generation. Group 4 was treated with 90 days of 0.1% (1 mg/ml) chitosan oligosaccharide. Group 5 was treated with 365 days of 0.1% (1 mg/ml) chitosanoligo saccharide. All experimental groups were used to 10 rat. The results were as follow: The RER dilation was observed Group 4. However, there were no significantly changes of ultrastructures in the other groups compared to the control. It was concluded that chitosanoligosaccharide can be used for nontoxic natural material.

• Fisheries and Aquatic Sciences
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• v.6 no.2
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• pp.66-73
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• 2003

To understand the physiology of a suspension-feeding bivalve and its potential impacts on the dynamics of red tides on tidal flats, rates of clearance and ingestion of Glauconome chinensis were measured as a function of algal concentration, when the bivalve was fed on a nontoxic strain of red tide dinoflagellate Prorocentrum minimum, Cochlodinium polykrikoides or Scrippsiella trochoidea. With increasing algal concentration, weight-specific clearance rate increased rapidly at lower concentrations and after reaching the maximum at ca. 0.2 to 1.0 mgC/L, it decreased at higher concentrations. Maximum clearance rate was nearly equal for different algal species and ranged between 2.1 and 2.6 L/g/hr. Weight-specific ingestion rate also increased at lower algal concentrations but saturated at higher concentrations. Maximum ingestion rate was 2 to 10 fold different with different algal species: S. trochoidea (10.1 mgC/g/hr), P. minimum (3.9 mgC/g/hr), and C. polykrikoides (0.99 mgC/g/hr). Nitrogen and protein content showed that S. trochoidea is the best among the tested three red tide dinoflagellates. The maximum filtration capacity, calculated by combining the data on ingestion rate from laboratory experiments and those from the field for the density of the bivalve and the red tide dinoflagellates was 4.7, 1.4, and 25.3 tons/m2/day for P. minimum, C. polykrikoides, and S. trochoidea, respectively. It is hypothesized that the abundant suspension-feeding bivalves in tidal flats can effectively mitigate the outbreak of red tides.