• Journal of Adhesion and Interface
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• v.13 no.3
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• pp.101-108
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• 2012

Narrowly dispersed poly(BMA-co-MMA) and PBMA latices (PSD : 1.002~1.008) were synthesized successfully by surfactant-free emulsion polymerization with 2,2' azobis(2-methyl-propionamidine) dihydrochloride (AIBA) and $K_2S_2O_8$ (KPS). The number average particle diameter and the number average molecule weight were found to be 160~494 nm and (1.25~7.55) ${\times}10^4$, respectively. The influences of BMA/MMA ratio, monomer and initiator concentrations, addition of DVB/EGDMA crosslink agent, and polymerization temperature on the polymerization rates and on the particle size and molecular weight were studied. The rate of polymerization increased with increasing MMA concentration in BMA/MMA weight ratio. The particle diameter as well as the polymer molecular weight could be controlled easily by controlling the BMA/MMA weight ratio, monomer concentration, AIBA and KPS concentration, and polymerization temperature.

• Mycobiology
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• v.45 no.1
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• pp.44-47
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• 2017

Ginseng damping-off, caused by the fungal pathogens Rhizoctonia solani and Pythium sp., is a critical disease in ginseng seedling. In a continuing effort to find microorganisms with the potential of acting as a biocontrol agent against Rhizoctonia damping-off, we found that a Streptomyces sp. A501 showed significant antifungal activity against Rhizoctonia solani. In field experiment to test the efficacy of Streptomyces sp. A501 in controlling ginseng damping-off, the incidence of damping-off disease was meaningfully reduced when ginseng seeds were soaked in the culture broth of Streptomyces sp. A501 before sowing. To perform characterization of the antifungal compound, we isolated it from the culture broth of strain A501 through Diaion HP-20 and silica gel column chromatographies and preparative high-performance liquid chromatography. The structure of the antifungal compound was assigned as fungichromin by spectroscopic methods, mainly nuclear magnetic resonance and electrospray ionization-mass analysis.

• Journal of the korean academy of Pediatric Dentistry
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• v.45 no.3
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• pp.393-399
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• 2018

The aim of this review is to introduce about the issue of benzocaine and methemoglobinemia. Through blocking the pain during dental treatment, fear and anxiety of patients will be reduced. Thus, anesthetic agent containing benzocaine is commonly used while controlling the pain of patients during treatment. However, on May 28, 2018, the Ministry of Food and Drug Safety reported a medication safety report about restricting the use of benzocaine-containing agents in infants under 24 months and children. Also, they recommended a cautious use to adolescents and adults to prevent methemoglobinemia (MHb). This report was published due to an advice from Food and Drug Administration (FDA) on May 23, 2018. When using agents containing benzocaine, dentists must consider the probability of MHb and prepare for early diagnosis and appropriate action. Since 1930s, methylene blue is known to cure MHb patients. Therefore, the proper use of methylene blue for emergencies and diagnosis methods for early diagnosis of MHb should be familiar to dentists planning for the use of topical anesthetic agents. Dentists should be trained for emergency situation of MHb caused by the use of benzocaine.

• BMB Reports
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• v.44 no.8
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• pp.506-511
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• 2011

Mammalian Target of Rapamycin (mTOR) is a serine/threonine kinase and that forms two multiprotein complexes known as the mTOR complex 1 (mTORC1) and mTOR complex 2 (mTORC2). mTOR regulates cell growth, proliferation and survival. mTORC1 is composed of the mTOR catalytic subunit and three associated proteins: raptor, mLST8/$G{\beta}L$ and PRAS40. mTORC2 contains mTOR, rictor, mLST8/$G{\beta}L$, mSin1, and protor. Here, we discuss mTOR as a promising anti-ischemic agent. It is believed that mTORC2 lies down-stream of Akt and acts as a direct activator of Akt. The different functions of mTOR can be explained by the existence of two distinct mTOR complexes containing unique interacting proteins. The loss of TSC2, which is upstream of mTOR, activates S6K1, promotes cell growth and survival, activates mTOR kinase activities, inhibits mTORC1 and mTORC2 via mTOR inhibitors, and suppresses S6K1 and Akt. Although mTOR signaling pathways are often activated in human diseases, such as cancer, mTOR signaling pathways are deactivated in ischemic diseases. From Drosophila to humans, mTOR is necessary for Ser473 phosphorylation of Akt, and the regulation of Akt-mTOR signaling pathways may have a potential role in ischemic disease. This review evaluates the potential functions of mTOR in ischemic diseases. A novel mTOR-interacting protein deregulates over-expression in ischemic disease, representing a new mechanism for controlling mTOR signaling pathways and potential therapeutic strategies for ischemic diseases.

• Research in Plant Disease
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• v.16 no.3
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• pp.331-335
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• 2010

The purpose of this study was to develop a method to effectively control mosses that are generated in container. To meet the goals, 6 kinds of chemical agents at different concentrations were applied to the container containing seedlings of Pinus densiflora with growing liverwort (Marchantia polymorpha) and Chamaecyparis obtusa with growing haircap moss (Polytrichum commune). It was found that quinoclamine was the most effective chemical agent to control mosses. Quinoclamine was effective in controlling liverwort (100% controlled) and haircap moss (95.5% controlled) at its concentration of 0.9 g/l. Next to quinoclamine, it was found that haircap moss and liverwort was effectively controlled by pyroligneous liquid which was followed by flumioxazin and oxyfluorfen. Seedling damages were observed in both two species treated with higher concentration of flumioxazin and oxyfluorfen.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.11
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• pp.416-424
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• 2019

In Korea, press concrete in basements is mainly applied using plain concrete. This system has undesirable defects such as cracks caused by plastic shrinkage and irregular temperature distribution. To solve this problem, metal lath and fibers have been used in the past. However, they have not been effective in controlling cracks. This study analyzed the reduction of plastic shrinkage cracking for press concrete using various admixtures in a basement has been. In the air contents test, the specimens with various admixtures showed air contents similar to plain concrete (4.5±1.5%). The specimens using silica fume, super plasticizer agent, and SBR showed higher compressive strength by about 10-15% than plain concrete. Cracking decreased when the MC, super plasticizer, and SBR were added. When MC was used in the concrete, the plastic shrinkage did not occur.

• Herbal Formula Science
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• v.25 no.3
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• pp.363-374
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• 2017

Dried fruits of Schizandra chinensis Baillon, Fructus Schisandrae, have been widely used for many years to prevent and treat various diseases in Asian countries including Korea and Russia. It has recently been reported that extracts of Fructus Schisandrae are effective for controlling muscle and skeletal diseases. In this study, we investigated the efficacy of ethanol extract of Fructus Schisandrae (EEFS) on apoptosis and inflammatory response in gastrocnemius muscle of dexamethasone-induced catabolic muscle atrophy mice as part of natural substance discovery and functional analysis for improving muscle function. According to the results of this study, EEFS supplementation attenuated body weight gains and suppressed calf thickness loss in dexamethasone-induced muscle atrophic mice. Gastrocnemius muscle immunohistochemistry showed that expression of caspase-3 and poly(ADP-ribose) polymerase, which are representative apoptotic markers, was markedly increased in dexamethasone control mice; however, their expression was effectively reduced in the EEFS-fed mice. EEFS supplementation also prevented dexamethasone-induced increases in immunoreactivity of muscle fibers for myostatin, an important negative regulator of skeletal muscle mass. In addition, EEFS significantly normalized the increased numbers of nitrotyrosine, 4-hydroxynonenal and inducible nitric oxide synthase-positive muscle fibers compared to that found in dexamethasone control mice. These results suggest that EEFS protects dexamethasone-induced muscular atrophy by decreasing apoptosis and inflammatory responses, and EEFS is more likely to be developed as a muscle strengthening agent.

• Journal of Physiology & Pathology in Korean Medicine
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• v.28 no.3
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• pp.317-321
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• 2014

Amyloid-${\beta}$ protein ($A{\beta}$) is a pathological component of Alzheimer's disease (AD) by participating in the senile plaque formation in the patient's brain. Although the exact mechanism of $A{\beta}$ toxicity is not fully elucidated, it is considered to be closely related to its fibrillation process. For prevention of AD, recent studies have suggested various small molecules which inhibit $A{\beta}$ fibrillation. In this report, ${\beta}$-asarone found in acorus plant has been investigated as an anti-amyloid molecule. ${\beta}$-Asarone was demonstrated to prevent in vitro fibrillation of $A{\beta}$ by inducing the oligomer formation that obviously decreased cytotoxicity. Therefore, ${\beta}$-asarone could be suggested as an inhibitory agent of $A{\beta}$ fibrillation and toxicity, which would help us not only to understand underlying principle of amyloidogenesis mechanism but also to develop a controlling strategy toward AD.

• The Plant Pathology Journal
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• v.24 no.2
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• pp.131-142
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• 2008

Magnaporthe oryzae, the causal agent of the rice blast disease, poses a worldwide threat to stable rice production. The large-scale functional characterization of genes controlling the pathogenicity of M. oryzae is currently under way, but little is known about heat shock protein 40 (Hsp40) function in the rice blast fungus or any other filamentous plant pathogen. We identified 25 genes encoding putative Hsp40s in the genome of M. oryzae using a bioinformatic approach, which we designated M. oryzae heat shock protein forty (MHF 1-25). To elucidate the roles of these genes, we characterized the functions of MHF16 and MHF21, which encode type ill and type n Hsp40 proteins, respectively. MHF16 and MHF21 expression was not significantly induced by heat shock, but it was down-regulated by cold shock. Knockout mutants of these genes $({\Delta}$mhf16 and ${\Delta}$mhf21) were viable, but conidiation was severely reduced. Moreover, sectoring was observed in the ${\Delta}mhf16$ mutant when it was grown on oatmeal agar medium. Conidial germination, appressorium formation, and pathogenicity in rice were not significantly affected in the mutants. The defects in conidiation and colony morphology were fully complemented by reintroduction of wild type MHF16 and MHF21 alleles, respectively. These data indicate that MHF16 and MHF21 play important roles in conidiation in the rice blast fungus.

• Journal of Microbiology and Biotechnology
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• v.15 no.6
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• pp.1337-1345
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• 2005

Vibrio vulnificus is the causative agent of foodborne diseases such as gastroenteritis and life-threatening septicemia. Microbial pathogenicity is a complex phenomenon in which expression of numerous virulence factors is frequently controlled by a common regulatory system. In the present study, a mutant exhibiting decreased cytotoxic activity toward intestinal epithelial cells was screened from a library of V. vulnificus mutants constructed by a random transposon mutagenesis. By a transposon-tagging method, an open reading frame, fexA, a homologue of Escherichia coli areA, was identified and cloned. The nucleotide and deduced amino acid sequences of the fexA were analyzed, and the amino acid sequence of FexA from V. vulnificus was $84\%\;to\;97\%$ similar to those of AreA, an aerobic respiration control global regulator, from other Enterobacteriaceae. Functions of the FexA were assessed by the construction of an isogenic mutant, whose fexA gene was inactivated by allelic exchanges, and by evaluating its phenotype changes in vitro and in mice. The disruption of fexA resulted in a significant alteration in growth rate under aerobic as well as anaerobic conditions. When compared to the wild-type, the fexA mutant exhibited a substantial decrease in motility and cytotoxicity toward intestinal epithelial cell lines in vitro. Furthermore, the intraperitoneal $LD_{50}$ of the fexA mutant was approximately $10^{1}-10^{2}$ times higher than that of parental wild-type. Therefore, it appears that FexA is a novel global regulator controlling numerous genes and contributing to the pathogenesis as well as growth of V. vulnificus.