• Korean Journal of Materials Research
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• v.22 no.7
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• pp.379-383
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• 2012

$TiO_2$ thin films consisting of positively charged poly(diallyldimethylammonium chloride)(PDDA) and negatively charged titanium(IV) bis(ammonium lactato) dihydroxide(TALH) were successfully fabricated on glass beads by a layer-by-layer(LBL) self-assembly method. The glass beads used here showed a positive charge in an acid range and negative charge in an alkaline range. The glass beads coated with the coating sequence of(PDDA/TALH)n showed a change in the surface morphology as a function of the number of bilayers. When the number of bilayers(n) of the(PDDA/TALH) thin film was 20, Ti element was observed on the surface of the coated glass beads. The thin films coated onto the glass beads had a main peak of the (101) crystal face and were highly crystallized with XRD diffraction peaks of anatase-type $TiO_2$ according to an XRD analysis. In addition, the $TiO_2$ thin films showed photocatalytic properties such that they could decompose a methyl orange solution under illumination with UV light. As the number of bilayers of the(PDDA/TALH) thin film increased, the photocatalytic property of the $TiO_2$-coated glass beads increased with the increase in the thin film thickness. The surface morphologies and optical properties of glass beads coated with $TiO_2$ thin films with different coating numbers were measured by field emission scanning electron microscopy(FE-SEM), X-ray diffraction(XRD) and by UV-Vis spectrophotometry(UV-vis).

• Korean Journal of Microbiology
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• v.46 no.1
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• pp.63-67
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• 2010

Proteases catalyze hydrolytic cleavage of a peptide bond between amino acids and occupy pivotal positions in application in physiological and commercial fields. During the screening for novel bacteria producing extracellular protease, two bacterial strains, WD12 and WD32, were isolated from rotten trees and they made clear zone on LB plates supplemented with 1% skim milk. The similarities of 16S rRNA gene sequence of either WD12 or WD32 to GenBank database showed the highest to Pseuoxanthomonas mexicana as 97.8 and 99.8%, respectively. Phylogenetic analysis showed that both isolated was located within the cluster comprising P. mexicana and P. japonesis. WD12 and WD32 were catalase- and oxidase-positive, Gram-negative rod strains. In case of WD12, it could assimilate malate, but could not assimilate D-mannose, which were different characteristics from P. mexicana. Both Pseuoxanthomonas sp. WD12 and WD32 optimally produced extracellular protease at $35-37^{\circ}C$, and maximal activity showed as 656 unit/ml and 267 unit/ml, respectively.

• Microbiology and Biotechnology Letters
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• v.38 no.4
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• pp.379-384
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• 2010

We isolated microorganisms presenting high enzymatic activities for amylase, cellulase, protease, lipase or fibrinolysis from Korean traditional soybean sauce and paste. Then, the physiological properties and 16S rRNA sequences of isolated microorganisms were analyzed. All of the isolated 13 strains possessing high extra cellular enzyme activities have higher amylase and cellulase activities than Bacillus subtilis KACC 10114. All the selected strains have protease activities except for D2-14. Except D8-8 and K4-1, other strains have lipase activity. D2-7, D8-8 and K4-1 strains have higher fibrinolytic activities than others, while D8-2 strain has no activity. Most of the selected strains showed antibacterial activity even in gram positive and gram negative bacteria and yeast. Gene sequence analysis of 16S rRNA from isolated strains revealed that all the selected strains were member of Bacillus species.

• Korean Journal of Microbiology
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• v.51 no.4
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• pp.364-373
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• 2015

As an effort to utilize alginate, 103 bacterial isolates that were positive for the alginate lyase activity were isolated from various clams and seawater samples collected in Incheon coastal area. Among them, 3 strains (M1-2-1, M6-1, and C8-15) were finally selected for further analysis based on their activities at higher levels than others. These isolates were all Gram-negative and rod shaped halophilic bacteria with motility. According to their physiological and biochemical properties as well as DNA sequence of their 16S rRNA genes, M1-2-1 and M6-1 were identified as a member of genus Pseudoalteromonas and C8-15 belonged to genus Vibrio. They exhibited the alginate degrading activity at the maximal level when they were cultured in APY broth for 6-8 h at $25^{\circ}C$. Both their growth and the enzyme activity were greatly enhanced when NaCl was added to the growth medium. The crude alginate lyases from the supernatants of the bacterial cultures showed the highest activity at $45^{\circ}C$ and pH 7.0-8.0. M1-2-1 and M6-1 produced 2.723 and 1.976 g/L of reducing sugar from alginate, respectively, suggesting that they have potential for commercial application.

• Journal of Life Science
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• v.13 no.6
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• pp.871-878
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• 2003

A marine bacterium (strain BKl) that produces extracellular enzymes capable of decomposing complex polysac-charides, such as agar, chitin, carboxymethylcellulose, xylan and mannan, was isolated from the marine red alga Porphyra dentata. Strain BKl was gram-negative, aerobic, catalase- and oxidase-positive, polarly flagellated bacilli that produce gelatinase and urease, but not decarboxylases. The G+C content of the DNA was 51.6 mol%. The major isoprenoid quinone component was identified as an ubiquinone-8, and the major cellular fatty acids were C16:0, C16:1 w6c and C18:1 w7c. Comparative 16S rRNA sequence analysis placed strain BK1 with members of the genus Pseudomonas. On the basis of phenotypic and genotypic data, the strain BK1 was shown to be a member of the subgroup of Pseudomonas, and named as Pseudomonas sp. BK1.

• Microbiology and Biotechnology Letters
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• v.36 no.4
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• pp.276-284
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• 2008

A lactic acid bacterium having antifungal activity was isolated from kimchi. It was identified as Lactobacillus plantarum based on its morphological and biochemical properties, and 16S rRNA sequence, and designated as Lb. plantarum AF1. This isolate inhibited the growth of Aspergillus flavus ATCC 22546, A. fumigatus ATCC 96918, A. petrakii PF-1, A. ochraceus PF-2, A. nidulans PF-3, Epicoccum nigrum KF-1, and Cladosporium gossypiicola KF-2 under a dual culture overlay assay. Also, the antimicrobial activity was found to be active against various species of Gram-positive and Gram-negative bacteria. The antifungal activity was found to be stable after heat ($121^{\circ}C$, 15 min) and proteolytic enzyme treatment, but it was unstable over pH 5.0. The antifungal compound(s) was estimated to have a low molecular mass (below 3,000 Da).

• Journal of Life Science
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• v.22 no.5
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• pp.605-612
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• 2012

Spore-forming bacteria are being used as probiotic supplements for human and animal use, due to their low pH stability and ability to survive the gastric barrier. In this study, the BCNU 9028 strain was screened from meju, a Korean fermented soybean food starter. Biochemical and physiological characteristics, as well as 16S rDNA sequence analyses, indicate that this strain belongs to the genus $Bacillus$. $Bacillus$ sp. BCNU 9028 showed a 92% survivability at pH 2.5 and could also withstand 0.3% ox bile. Furthermore, it was postulated that $Bacillus$ sp. BCNU 9028 could prevent biofilm formation and adherence of food-borne pathogens such as $Listeria$ $monocytogenes$, $S.$ $aureus$ and $E.$ $coli$ on the basis of its autoaggregation and coaggregation capacity with food-borne pathogens. It was shown that BCNU 9028 has good abilities to adhere to the intestinal tract from its hydrophobic character (63.3%). The $Bacillus$ sp. BCNU 9028 strain especially elicited antibacterial activity against both Gram-positive and -negative pathogens. These findings suggested that the $Bacillus$ sp. BCNU 9028 strain could be used as a potential probiotic.

• Korean Journal of Medicinal Crop Science
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• v.3 no.1
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• pp.16-20
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• 1995

This study was carried out to know the effects of $N,\:P_2O_5,\:K_2O$ application and mulching materials on the yield and quality of Peusedanum japonicum. And conducted from 1990 to 1992 in the south region. The emergency rate by mulching materials was 80% on non-mulching, 74% on black P.E mulching, but 49% on the transparent P.E mulching. The yield of dried root on the transparent P.E mulching was increased 7% compared to non-mulching. The decreasing rate of yield was increased with the sequence of $N>P_2O_5>K_2O_5$. The significant negative correlation was obtained between the content of ash and nitrogen application, and the significant positive correation between the content of ash and potassium application. The contents of ash, acid insolubleash, and $C_2H_5\:OH$ OH extract were not affected by the treat-ment of mulching materials. When Peusedanum japonicum was cultivated in the south region for one year, optimum application of fertilizers was $N-P_2O_5-K_2O_5=21-13-10kg/10a.$

• Investigative Magnetic Resonance Imaging
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• v.20 no.2
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• pp.105-113
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• 2016

Purpose: Susceptibility vessel sign (SVS) on gradient echo image, which is caused by MR signal loss due to arterial thrombosis, has been reported in acute middle cerebral artery (MCA) infarction. However, the reported sensitivity and diagnostic accuracy of SVS have been variable. Susceptibility-weighted imaging (SWI) is a newly developed MR sequence. Recent studies have found that SWI may be useful in the field of cerebrovascular diseases, especially for detecting the presence of prominent veins, microbleeds and the SVS. The purpose of this study was to evaluate the diagnostic values of SWI for the detection of hyperacute MCA occlusion. Materials and Methods: Sixty-nine patients (37 males, 32 females; 46-89 years old [mean, 69.1]) with acute stroke involving the MCA territory underwent MR imaging within 6 hours after the symptom onset. MR examination included T2, FLAIR (fluid-attenuated inversion recovery), DWI, SWI, PWI (perfusion-weighted imaging), contrast-enhanced MR angiography (MRA) and contrast-enhanced T1. Of these patients, 28 patients also underwent digital subtraction angiography (DSA) within 2 hours after MR examination. Presence or absence of SVS on SWI was assessed without knowledge of clinical, DSA and other MR imaging findings. Results: On MRA or DSA, 34 patients (49.3%) showed MCA occlusion. Of these patients, SVS was detected in 30 (88.2%) on SWI. The sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of SWI were 88.2%, 97.1%, 96.8%, 89.5% and 92.8%, respectively. Conclusion: SWI was sensitive, specific and accurate for the detection of hyperacute MCA occlusion.

• Molecules and Cells
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• v.45 no.12
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• pp.886-895
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• 2022

Malignant rhabdoid tumor (MRT) is a highly aggressive pediatric malignancy with no effective therapy. Therefore, it is necessary to identify a target for the development of novel molecule-targeting therapeutic agents. In this study, we report the importance of the runt-related transcription factor 1 (RUNX1) and RUNX1-Baculoviral IAP (inhibitor of apoptosis) Repeat-Containing 5 (BIRC5/survivin) axis in the proliferation of MRT cells, as it can be used as an ideal target for anti-tumor strategies. The mechanism of this reaction can be explained by the interaction of RUNX1 with the RUNX1-binding DNA sequence located in the survivin promoter and its positive regulation. Specific knockdown of RUNX1 led to decreased expression of survivin, which subsequently suppressed the proliferation of MRT cells in vitro and in vivo. We also found that our novel RUNX inhibitor, Chb-M, which switches off RUNX1 using alkylating agent-conjugated pyrrole-imidazole polyamides designed to specifically bind to consensus RUNX-binding sequences (5'-TGTGGT-3'), inhibited survivin expression in vivo. Taken together, we identified a novel interaction between RUNX1 and survivin in MRT. Therefore the negative regulation of RUNX1 activity may be a novel strategy for MRT treatment.