• Journal of Microbiology and Biotechnology
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• v.26 no.8
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• pp.1457-1463
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• 2016

Vibrio anguillarum, a devastating pathogen causing vibriosis among marine fish, is prevailing in worldwide fishery industries and accounts for grievous economic losses. Therefore, a rapid on-site detection and diagnostic technique for this pathogen is in urgent need. In this study, two mouse monoclonal antibodies (MAbs) against V. anguillarum, 6B3-C5 and 8G3-B5, were generated by using hybridoma technology and their isotypes were characterized. MAb 6B3-C5 was chosen as the detector antibody and conjugated with quantum dots. Based on MAb 6B3-C5 labeled with quantum dots, a modified dot blot assay was developed for the on-site determination of V. anguillarum. It was found that the method had no cross-reactivity with other than V. anguillarum bacteria. The detection limit (LOD) for V. anguillarum was 1 × 10³ CFU/ml in cultured bacterial suspension samples, which was a 100-fold higher sensitivity than the reported colloidal gold immunochromatographic test strip. When V. anguillarum was mixed with turbot tissue homogenates, the LOD was 1 × 10³ CFU/ml, suggesting that tissue homogenates did not influence the detection capabilities. Preenrichment with the tissue homogenates for 12 h could raise the LOD up to 1 × 10² CFU/ml, confirming the reliability of the method.

• Korean Journal of Microbiology
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• v.50 no.1
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• pp.1-7
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• 2014

Site-specific incorporation of unnatural amino acids (SSIUA) into protein can be achieved in vivo by coexpression of an orthogonal pair of suppressor tRNA and engineered aminoacyl-tRNA synthetase (ARS) that specifically ligates an unnatural amino acid to the suppressor tRNA. As a step to develop the SSIUA technique in Escherichia coli, here we established a new 2-step screening system that can be used for selecting an ARS variant(s) that ligates an unnatural amino acid to a suppressor tRNA. A positive selection system consists of chloramphenicol acetyl transferase gene containing an amber mutation at the $27^{th}$ residue, and efficiently concentrated amber suppressible ARS with a maximum enrichment factor of $9.0{\times}10^5$. On the other hand, a negative selection system was constructed by adding multiple amber codons in front of a lethal gene encoding the control of cell death B toxin (ccdB) which acts as an inhibitory protein of bacterial topoisomerase II. Amber suppression of ccdB by an orthogonal pair of Saccharomyces cerevisiae tyrosyl-tRNA synthetase (TyrRS) and an amber suppressor tRNA significantly inhibits bacterial growth. This selection system was also able to efficiently remove amber suppressible ARS which could ligate natural amino acids to the suppressor tRNA. Thus, sequential combination of these two selection systems might be able to function as a powerful tool for selecting an ARS variant that specifically ligates an unnatural amino acid to the suppressor tRNA from an ARS mutant pool.

• The Korean Journal of Pain
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• v.10 no.1
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• pp.64-68
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• 1997

Background : Patients mover more as their post operative pain decrease. With the increase in movement there will be a tendency for the epidural catheter to migrate out of its original position. We studied 2 methods of fixation of the epidural catheter and the changes in position as related to patient movement. Methods : Patients were divided into two groups. Patients in Group A had their epidural catheter formed with a circular loop at the (skin) exit site then directed over the right shoulder. Group B had the epidural catheter flxed with Fixomull on the exit site without forming a circular loop. At the end of the operation, 3 mg of epidural morphine was injected via indwelling epidural catheter for postoperative pain control. Epidural catheter depth was measured 24 hours later. Results : The overall rate of migration of epidural catheter was 61.9%. In Group A, number of patients whose catheter migrated over 0.5 cm was 23(69.9%) with 14 inward migration and 9 outward migration. Group B had 16(53%) patients catheters migrate over 0.5 cm, with 2 patients having inward migration and 14 outward migration. Conclusions : Although the rates of migration of epidural catheter were similar for both groups, the number of inner migration of catheter, which could result serious complications, was significantly lower in Group B than Group A. Based on our results we recommend the epidural catheter be fixed without a circular loop.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.23
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• pp.10299-10306
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• 2015

The esophageal squamous cell carcinoma (ESCC) is thought to develop through a multi-stage process. Epigenetic gene silencing constitutes an alternative or complementary mechanism to mutational events in tumorigenesis. Posttranscriptional regulation of human leukocyte antigen class I (HLA-I) and antigen processing machinery (APM) proteins expression may be associated with novel epigenetic modifications in cancer development. In the present study, we determined the expression levels of HLA-I antigen and APM components by immunohistochemistry. Then by a bisulfite-sequencing PCR (BSP) approach, we identified target CpG islands methylated at the gene promoter region of APM family genes in a ESCC cell line (ECa109), and further quantitative analysis of CpG site specific methylation of these genes in cases of Kazakh primary ESCCs with corresponding non-cancerous esophageal tissues using the Sequenom MassARRAY platform. Here we showed that the development of ESCCs was accompanied by partial or total loss of protein expression of HLA-B, TAP2, LMP7, tapasin and ERp57. The results demonstrated that although no statistical significance was found of global target CpG fragment methylation level sof HLA-B, TAP2, tapasin and ERp57 genes between ESCC and corresponding non-cancerous esophageal tissues, there was significant differences in the methylation level of several single sites between the two groups. Of thesse only the global methylation level of LMP7 gene target fragments was statistically higher ($0.0517{\pm}0.0357$) in Kazakh esophageal cancer than in neighboring normal tissues ($0.0380{\pm}0.0214$, p<0.05). Our results suggest that multiple CpG sites, but not methylation of every site leads to down regulation or deletion of gene expression. Only some of them result in genetic transcription, and silencing of HLA-B, ERp57, and LMP7 expression through hypermethylation of the promoters or other mechanisms may contribute to mechanisms of tumor escape from immune surveillance in Kazakh esophageal carcinogenesis.

• The KIPS Transactions:PartB
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• v.16B no.2
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• pp.157-161
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• 2009

Minimum Letter Flips(MLF) and Weighted Minimum Letter Flips(WMLF) can perform the haplotype reconstruction more accurately from SNP fragments when they have many errors and gaps by introducing the related genotype information. And it is known that WMLF is more accurate in haplotype reconstruction than those based on the MLF. In the paper, we analyze two models under the conditions that the different rates of homozygous site in the genotype information and the different confidence levels according to the sequencing quality. We compare the performance of the two models using neural network and genetic algorithm. If the rate of homozygous site is high and sequencing quality is good, the results of experiments indicate that WMLF/GI has higher accuracy of haplotype reconstruction than that of the MCIH especially when the error rate and gap rate of SNP fragments are high.

• Journal of Korea Foundry Society
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• v.34 no.5
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• pp.162-169
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• 2014

The effect of the mold preheat temperature on the solidification crack strength was investigated in AC2B aluminum alloy. A tension type apparatus as part of a solidification crack test which could measure the stress-strain relationship quantitatively was utilized. The evaluation of the solidification crack strength with varying mold preheat temperatures was performed by the test procedure established in this research. When the mold preheat temperatures were $250^{\circ}C$, $150^{\circ}C$ and $50^{\circ}C$, the solidification crack strengths were found to be $7.8Kgf/cm^2$, $12.9Kgf/cm^2$ and $28.6Kgf/cm^2$, respectively. In the same way, when the mold preheat temperatures were $250^{\circ}C$, $150^{\circ}C$ and $50^{\circ}C$, the corresponding temperatures of the failure sites were $610^{\circ}C$, $600^{\circ}C$ and $571^{\circ}C$, and the calculated solid fractions were 14.0%, 29.3% and 50.8% when the specimens failed, respectively. The solidification crack strength increased in proportion to the solid fraction of the failure site. The solidification crack strength obtained in this test is assumed to reflect the effects of metallurgical factors on the thermo-plastic characteristics of a solidifying alloy such as the grain size of the solid, the grain morphology, and the distribution of solid grain.

• Molecules and Cells
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• v.43 no.6
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• pp.572-580
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• 2020

Transient receptor potential ankyrin 1 from rattlesnakes (rsTRPA1) and boas (bTRPA1) was previously proposed to underlie thermo-sensitive infrared sensing based on transcript enrichment in infrared-sensing neurons and hyper-thermosensitivity expressed in Xenopus oocytes. It is unknown how these TRPA1s show thermosensitivities that overwhelm other thermoreceptors, and why rsTRPA1 is more thermosensitive than bTRPA1. Here, we show that snake TRPA1s differentially require Ca²⁺ for hyper-thermosensitivity and that predisposition to cytosolic Ca²⁺ potentiation correlates with superior thermosensitivity. Extracellularly applied Ca²⁺ upshifted the temperature coefficients (Q10s) of both TRPA1s, for which rsTRPA1, but not bTRPA1, requires cytosolic Ca²⁺. Intracellular Ca²⁺ chelation and substitutive mutations of the conserved cytosolic Ca²⁺-binding domain lowered rsTRPA1 thermosensitivity comparable to that of bTRPA1. Thapsigargin-evoked Ca²⁺ or calmodulin little affected rsTRPA1 activity or thermosensitivity, implying the importance of precise spatiotemporal action of Ca²⁺. Remarkably, a single rattlesnake-mimicking substitution in the conserved but presumably dormant cytosolic Ca²⁺-binding domain of bTRPA1 substantially enhanced thermosensitivity through cytosolic Ca²⁺ like rsTRPA1, indicating the capability of this single site in the determination of both cytosolic Ca²⁺ dependence and thermosensitivity. Collectively, these data suggest that Ca²⁺ is essential for the hyper-thermosensitivity of these TRPA1s, and cytosolic potentiation by permeating Ca²⁺ may contribute to the natural variation of infrared senses between rattlesnakes and boas.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.12
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• pp.1161-1168
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• 2009

This research was conducted on characteristic of offensive odors in Shihwa industrial complex. Result of blocks distribution of TVOC indicates that mechanic block, site D, was the highest concentration (74 ppb). Chemistry block, site A, was the second highest concentration (50 ppb). Also, mixed blocks, metal blocks and park etc. were measured almost similar concentration about 30 ppb, but mixed block, site F, was the place where concentrations were the smallest. Average of TVOC was shown about 35 ppb concentration. Aldehydes including acetaldehyde, butyraldehyde and hydrogen sulfide concentrations were prevalent among offensive odors in Shihwa industrial complex. Comparing the offensive odor intensity mostly about acetaldehyde, butyraldehyde and hydrogen sulfide which contain high offensive odor intensity showed results that sites A, B (chemistry block) and site D, I (mechanic block) site H (metal block) have showed the intensity over 1. In the case of acetaldehyde, relatively the high odor intensities over '2' were able to obtain in many cases. The correlation coefficient (r) for hydrogen sulfide was 0.91, so that high positive correlation exists between offensive odor intensity and the hydrogen sulfide element. Butyraldehyde also showed high positive correlation coefficient, as 0.82. Correlation coefficient of acetaldehyde that had the highest value as offensive odor substance was 0.62, had somewhat correlation with offensive odor intensity.

• Bulletin of the Korean Chemical Society
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• v.32 no.5
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• pp.1620-1624
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• 2011

Homologated analogues 3a and 3b of potent and selective A3 adenosine receptor ligands, IB-MECA and dimethyl-IB-MECA were synthesized from commercially available 1-O-acetyl-2,3,5-tri-O-benzoyl-${\beta}$-D-ribofuranose (4) via $Co_2(CO)_8$-catalyzed siloxymethylation as a key step. Unfortunately, homologated analogues 3a and 3b did not show significant binding affinities at three subtypes of adenosine receptors, indicating that free rotation, resulting from homologation, induced unfavorable interactions in the binding site of the receptor maybe due to the presence of many conformations.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1986.12a
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• pp.524.3-524
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• 1986

Carboxymethyl cellulase (CMCase) produced by cloned B. megaterium was found to contain 5.2% carbohydrate but no metal ion. The enzyme was isoelectric at pH 7.23 and was high is basic amino acids. The N-terminal of the enzyme was glutamic acid. The cellulolytic activity of this enzyme was extended to the small molecular substrates such as from cellotriose to cellopentaose. In additon, the enzyme showed transglycoslation activity. The pK values of the enzyme we estimated to be 4.4 and 6.7, andthat of the enzyme-substrate complex were 4.2 and 7.2, respectively. The enzyme was not affected by the treatment with iodoacetic acid, but the modification of enzyme with carbodiimide and diethyl pyrocarbonate resulted in a marked loss of the enzyme activity. These results suggest that the active site of enzyme essentially contains carboxylic and imidazole group of amino acid residues.