• BMB Reports
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• 제40권5호
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• pp.783-790
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• 2007

Receptor binding plays an important role in determining host specificity of the Bacillus thuringiensis Cry $\delta$-endotoxins. Mutations in domains II and III have suggested the participation of certain residues in receptor recognition and insect specificity. In the present study, we expressed the cloned domain II-III fragment of Cry4Ba and examined its binding characteristics to mosquito-larval midgut proteins. The 43-kDa Cry4Ba-domain II-III protein over-expressed in Escherichia coli as inclusion bodies was only soluble when carbonate buffer, pH 10.0 was supplemented with 4M urea. After renaturation via stepwise dialysis and subsequent purification, the refolded domain II-III protein, which specifically reacts with anti Cry4Ba-domain III monoclonal antibody, predominantly exists as a $\beta$-sheet structure determined by circular dichroism spectroscopy. In vitro binding analysis to both histological midgut tissue sections and brush border membrane proteins prepared from susceptible Aedes aegypti mosquito-larvae revealed that the isolated Cry4Ba-domain II-III protein showed binding functionality comparable to the 65-kDa full-length active toxin. Altogether, the data present the 43-kDa Cry4Ba fragment comprising domains II and III that was produced in isolation was able to retain its receptor-binding characteristics to the target larval midgut proteins.

• Asian-Australasian Journal of Animal Sciences
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• 제21권8호
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• pp.1080-1087
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• 2008

Lipopolysaccharide binding protein (LBP) and CD14 protein play important roles in the defense against infection of Gram-negative bacteria. In the present study, tissue distribution and polymorphism of porcine LBP and CD14 genes were analyzed. Real-time PCR results showed that the porcine LBP gene was especially highly expressed in liver, while CD14 gene was highly expressed in liver and spleen tissues. A 1,732 bp cDNA fragment of porcine LBP gene and a 1,682 bp genomic DNA fragment of CD14 gene were isolated. Polymorphisms were identified in these two fragments and showed that there were 14 potential SNPs in the porcine LBP gene and 3 potential SNPs in the porcine CD14 gene. Three SNPs, 292G/A (Gly/Ser), 1168G/A (Ala/Thr) of the LBP gene and -61G/A of the CD14 gene, were genotyped using restriction fragment length polymorphism (RFLP) method. Association analyses indicated that polymorphism of the 292G/A locus was significantly associated with porcine immune traits hematocrit (HCT), IgG and delayed-type hypersensitivity (DTH) (p<0.01), and the 1168G/A locus was significantly associated with HCT and mean corpuscular volume (MCV) traits (p<0.05). No significant association was found between the -61G/A locus and immune traits of the pig. Our data indicated that the LBP gene was significantly associated with immune traits of pig. Also, we identified some SNPs which may be useful markers for disease-resistant breeding of pigs.

• Journal of Microbiology and Biotechnology
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• 제18권8호
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• pp.1475-1481
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• 2008

B3 antibody specifically binds the $Lewis^Y$-related carbohydrate antigen of many carcinomas, and it is used as a model antibody in this study. In a previous study, the Fab fragment of the antibody was fused to a 38 kDa truncated form of Pseudomonas exotoxin A, PE38, to make Fab-PE38, where PE38 is fused to the Fd fragment of the Fab domain. This parent monomer molecule, Fab-PE38, had no cysteine in the hinge region, and it could not make a disulfide bond to form a disulfide bond bridged homodimer. In this study, we constructed three different kinds of divalent Fab-toxin fusion homodimers where the toxin is fused to the light chain of Fab, $(Fab-PE38fl)_2$. In addition to the PE38 toxin fused to the light chain, these three molecules have different hinge sequences hi, h2, and h3 making Fabh1-, Fabh2-, and Fabh3-PE38fl monomers, respectively. These hinges contain only one cysteine on different positions of the hinge sequence. The disulfide bond between the hinge region of two monomers forms homodimers $(Fabh1-PE38fl)_2$, $(Fabh2-PE38fl)_2$, and $(Fabh3-PE38fl)_2$. The refolding yields of these dimers were 5-16-fold higher than a previously constructed dimer where the PE38 was fused to the Fd fragment $(Fabh2-PE38)_2$ [8]. Our data suggest that the steric repulsion between the two PE38s in $(Fabh1-PE38)_2$ during disulfide bridge formation is relieved by fusing it at the end of the light chain. The best cytotoxicity value of these dimers showed about 2.5-fold higher on an MCF7 cell line than that of the monovalent reference molecule in ng/ml scale, which is 15-fold higher in pM scale.

• 한국통신학회논문지
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• 제33권4A호
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• pp.450-457
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• 2008

에너지 효율적 전송기술은 무선 PAN(WPAN: Wireless Personal Area Network) 장치들과 같이 에너지 소모에 있어서 제약을 많이 받는 무선장치의 동작 시간을 최대화하기 위해서 필수적으로 요구되는 핵심 기술이다. 더욱이, WPAN이 TDMA 동작 방식과 연동되어 수행될 때, 할당된 각 time 슬롯에서 실제 물리적 전송의 QoS 요구 사항에 대한 보장은 설계시 만족시켜야 하는 또 다른 중요 설계 고려사항이다. 따라서, 본 논문에서는 TDMA 기반의 비경합 매체 접근 프로토콜과 함께 동작하는 WPAN을 위한 에너지-효율적이며 동시에 QoS를 고려한 전송 방법을 제안한다. 제안한 알고리즘을 통해서 전송파워, 물리적 데이터 전송율(변조 수준/방식), 에너지 소모 최소화, 그리고 동시에 할당된 time 구간에서 요구되는 QoS 만족시키는 fragment 크기 등에 대한 최적 조합을 결정할 수 있다. 제안한 알고리즘과 기존의 알고리즘과의 차이점은 전송파워, 데이터 전송율 및 fragment 크기에 대한 모든 파라미터의 조합을 찾는 것이다. 시뮬레이션 결과는 제안한 알고리즘을 통하여 처리량과 에너지 소모 측면에서 성능이 향상되었음을 보인다.

• Restorative Dentistry and Endodontics
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• 제38권4호
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• pp.222-226
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• 2013

Objectives: The aim of this study was to assess the influence of operator experience level on the lifespan of the WaveOne Primary file (Dentsply Maillefer, Ballaigues, Switzerland) in extracted teeth. Materials and Methods: Moderately curved canals of extracted maxillary and mandibular molars were randomly distributed into 2 groups: experienced and inexperienced operators. Ten files were allocated to each group (n = 10). Each canal was prepared until the working length was reached, and the same file was used to prepare additional canals until it separated. The number of canals prepared before file separation was recorded. The fragment length of each file was measured, and the location of the fragment in the canal was determined. Data were statistically analysed using the independent 2-sample t-test. Results: The 2 operators prepared a total of 324 moderately curved canals of maxillary and mandibular molars. There was no significant intergroup difference in the mean number of canals prepared (p = 0.27). The average lifespan of the WaveOne Primary file was 17.1 and 15.3 canals, and the longest lifespan was 25 and 20 canals, when used by experienced and inexperienced operators, respectively. There were no statistically significant intergroup differences in separated fragment length and location. Conclusions: Within the limitations of this study, operator experience level appears to have no effect on the lifespan of the WaveOne Primary file in preparation of moderately curved canals. Single teeth with multiple canals can be prepared safely even by a novice operator by using a single file.

• 한국축산식품학회지
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• 제30권3호
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• pp.403-409
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• 2010

Accurate methods for the identification of closely related species or breeds in raw and processed meats must be developed in order to protect both consumers and producers from mislabeling and fraud. This paper describes the development of DNA markers for the discrimination and improvement of Korean native pig (KNP) meat. The KIT gene is related to pig coat color and is often used as a candidate marker. A 538 bp fragment comprising intron 19 of the pig KIT gene was amplified by PCR using specific primers, after which the PCR amplicons of a number of meat samples from KNP and three major improved breeds (Landrace, Duroc and Yorkshire) were sequenced in order to find a nucleotide region suitable for PCR-RFLP analysis. Sequence data showed the presence of two nucleotide substitutions, g.276G>A and g.295A>C, between KNP and the improved pig breeds. Digestion of KIT amplicons with AccII enzyme generated characteristic PCR-RFLP profiles that allowed discrimination between meats from KNP and improved pig. KNP showed three visible DNA bands of 264/249, 199, and 75 bp, whereas DNA bands of 249, 199, and 90 bp were detected in the three improved pig breeds. Therefore, the 75 bp DNA fragment was specific only to KNP, whereas the 90 bp DNA fragment was specific to the improved breeds. The breed-specific DNA markers reported here that target the KIT gene could be useful for the identification of KNP meat from improved pig meats, thus contributing to the prevention of falsified breed labeling.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2005년도 제24회 춘계학술대회논문집
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• pp.47-52
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• 2005

이 논문은 열폭발 실험에서의 열적, 화학적, 기계적 행동의 결과에 대한 3차원 모델 결과를 나타낸다. 폭발이 관찰되기 전까지 제한된 고 폭발물은 시간당 $1^{\circ}C$의 비율로 가열된다. 임의의 Lagrangian-Euler 코드를 사용하여 모델링된 가열, 점화 그리고, deflagration 단계는 구조적에서 동적인 hydro 시간단계까지 변하는 넓은 범위의 시간 영역에서 다루어 질수 있다. Johnson-Cook Failure Model (JCFM)에 실험적 고장분포를 더하여 폭발기기의 균열방향과 fragment의 크기를 예측할 수 있는 모델을 개발한다.

• Archives of Pharmacal Research
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• 제24권5호
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• pp.446-454
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• 2001

Peptide fragments, isolated from proteolytic cleavage of thyroglobulin at specific sites, were examined for the iodination of tyrosine residues. The 50 kDa polypeptide, which was prepared from digestion of bovine thyroglobulin and continuous preparative SDS-PAGE, was subjected to reduction with DTT and alkylation with iodoacetic acid to generate S-car-boxymethylated peptide derivative, which was further hydrohysed by endoproteinase-Asp-N. Peptide products were separated by RP-HPLC, and each fraction was analyzed by LC/ESI-MS and MALDI-MS analyses. Based on the specificity of endoproteinase-Asp-N andthe mass spectra data, a peptide fragment turned out to correspond to a peptide, DALCCVKCPEGSYFQ (1438-1452), characterized by the presence of a thioredoxin box (CVKC) and a tyrosine residue. In addition, another peptide fragment (1453-1465) containing a thioredoxin box (CIPC) and a tyrosine residue was also observed. However, any evidence of iodination of the tyrosine residue present in these peptides was not provided. Meanwhile, tyrosine residues in the peptides, DVEEALAGKYLAGRFA (1366-1381) and DYSGLLLAFQVFLL (1290-1303) were found to be iodinated; mono- or diiodinated tyrosine residues, characteristic of a hormogenic site, existed in both peptides. In addition, the tyrosine residue in the peptide (1218-1252), corresponding to a hormonogenic site was also iodinated. Thus, there was a sharp difference of the susceptibility to oxidative iodination between the tyrosine residue in a hormonogenic site and that in a thioredoxin region. From these results, it is suggested that polypeptide region adjacent to tyrosine residues may govern the susceptibility of tyrosine to oxidative iodination.

• 한국작물학회지
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• 제44권2호
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• pp.166-170
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• 1999

The identification of quantitative trait loci (QTL) has the potential to enhance the efficiency of im- proving food processing traits of soybean. In this study, 92 restriction fragment length polymorphism (RFLP) loci and two morphological markers (W$_1$ and T) were used to identify QTL associated with food processing traits of soybean for sprout in 83 F$_2$-derived lines from a cross of ＇Pureun＇ x ＇Jinpum 2＇. The genetic map consisted of 76 loci which covered about 760 cM and converged into 20 linkage groups. Eighteen markers remained unlinked. Phenotypic data were collected for hypocotyl length, abnormal seedling rate, and sprout yield seven days after seed germination at 2$0^{\circ}C$. Based on the single-factor analysis of variance, eight independent markers were associated with hypocotyl length. Four of seven markers associated with abnormal seedling rate were identified as independent. Seven loci were associated with sprout yield. For three different traits, much of genetic variation was explained by the identified QTL in this population. Several RFLP markers in linkage group (LG) Bl were detected as being associated with three traits, providing a genetic explanation for the biological correlation of sprout yield with hypocotyl length (r=OA07＊＊＊) and with abnormal seedling rate (r=-406＊＊＊).

• Mycobiology
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• 제34권2호
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• pp.45-55
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• 2006

Although Fursarium oxysporum causes diseases in economically important plant hosts, identification of F. oxysporum formae speciales has been difficult due to confusing phenotypic classification systems. To resolve these complexity, we evaluated genetic relationship of nine formae speciales of F. oxysporum with random amplified polymorphic DNA (RAPD), amplified fragment length polymorphism (AFLP), and translation elongation factor-l alpha ($EF-1{\alpha}$) gene. In addition, the correlation between mycotoxin content of fusaric acid and isolates based on molecular marker data was evaluated using the modified Mantel's test. According to these result, these fusaric acid-producing strains could not identify clearly, and independent of geographic locations and host specificities. However, in the identification of F. oxysporum formae speciales, especially, AFLP analysis showed a higher discriminatory power than that of a the RAPD and $EF-1{\alpha}$ analyses, all three techniques were able to detect genetic variability among F. oxysporum formae speciales in this study.