• Journal of Biomedical Engineering Research
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• v.30 no.4
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• pp.333-340
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• 2009

MR compatible coaxial-slot antenna for microwave hyperthermia was developed while its structure and size of each part were determined by computer simulation using finite element method(FEM). Its local heating performance was evaluated using tissue-mimic phantom and swine muscles. 2% agarose gel mixed with 6mM/$\ell$ $MnCl_2$ as a biological tissue-mimic phantom was heated by the proposed antenna driven by a 2.45GHz microwave generator. The temperature changes of the phantom were monitored using multi-channel digital thermometer at the distance of 0mm, 5mm, 10mm and 20mm from the tip center of the antenna. Also muscle tissue of swine was heated for 2 and 5minutes with 50W and 30W of microwave generator powers, respectively, to evaluate the local heating performance of the antenna. MRI compatibility was also verified by acquiring MR images and MR temperature map. MR signals were acquired from the agarose gel phantom using $T2^*$ GRE sequence with 1.5T clinical MRI scanner(Signa Echospeed, GE, Milwaukee, WI, U.S.A.) at Pusan Paik Hospital and were transferred to PC in order to reconstruct MR images and temperature map using proton resonance frequency(PRF) method and laboratory-developed phase unwrapping algorithm. Authors found that it has no severe distortion due to the antenna inserted into the phantom. Finally, we can conclude that the suggested coaxial-slot antenna has an excellent local heating performance for both of tissue-mimic phantom and swine muscle, and it is compatible to 1.5T MRI scanner.

• KSBB Journal
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• v.14 no.6
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• pp.702-706
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• 1999

The genetic responses of aquaculturable seaweed Prophyra yezoensis tissue by acid shock have been compared using differential display technique. The tissue has been challenged in seawater containing 0.05% hydrogen chloride(pH 3.0) for 5 min, then rehabilitated in normal seawater for 10 min, 30 min, 60 min and 4 hrs, respectively. Total RNA was extracted by LiCl-guanidinium method. The cDNA was synthesized by reverse transcription with random hexamers and amplified by PCR with arbitrary primers. The genetic fragment disappeared by acid shock was selectively isolated from agarose gel and sequenced with a DNA auto sequencer. One of the acid-labile gene(605 bp) was identified as a dethiobiotin synthetase gene according to sequence alignment analysis by the NCBI BLAST search program.

• Korean journal of applied entomology
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• v.36 no.3
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• pp.264-269
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• 1997

Four strains of Bacillus thuringiensis were isolated froin the dead larvae of mulberry longicorn beetle (Apriong germari) and dung beetle (Aphodius apicalis). One nf four B. thuringiensis isolates turned out to be subspecies darinstadiensis but the remains were not identified using 33 B. thuringiensts flgellar ( H ) antibodies. Furthermore. bioassays of spore-parasporal inclusion protein mixture conducted against third instar larvae of A. gerrntrri or A. apicalis, second instar larvae of Bombyx mori, and third instar larvae of Cu1ex pipiens pullens showed that the isolates were non-toxic. To further confirm, four isolates were characterized and analysed by SDS-PAGE and agarose gel electrophoresis. The results revealed that parasporal protein and plasmid DNA patterns of four isolates are different from those of darmstadiensis and 20 known non-toxic B. thuringiensis strains, suggesting that the four isolates are novel non-toxic B. thuringiensis.

• Journal of Sericultural and Entomological Science
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• v.35 no.2
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• pp.120-128
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• 1993

The objective of this study is to identify plasmids of Bacillus thuringiensis var. kurstaki HD-1(B. t k HD-1) toxic to lepidopteran larvae. The results from agarose gel electrophoresis indicated that the bacterium contained 9 plasmids with approximate sizes of 1.4, 4.9, 5.4, 9.3, 10, 29, 44, 52, and 150 megadaltons(Md). By treating the wild type of B. t k HD-1 with either SDS or EtBr as curing agent, 26 cured mutants of the bacterium were obtained, 9 of them were crystallifereous(cry+) and the others acrystallifereous(cry-). Plasmids from B. t k HD-1 were transferred to B. cereus 569 strR cry- recipients(Bc569 M1). Among 13 isolates of Bc569 M1 transcipient, 11 of them were capable of producing the crystal toxic proteins. The plasmid patterns of Bc569 M1 transcipients and partially curved mutants of B. t k HD-1 on agarose gel electrophoresis suggested that the 29 and 44Md plasmids should be involved in the production of crystalline toxic proteins.

• Microbiology and Biotechnology Letters
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• v.16 no.4
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• pp.270-274
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• 1988

Samples used for the enrichment culture were collected from the sea water of suspected chronic petroleum contamination in the vicinity of Pusan, Chungmu and Ulsan ports, Korea. Alkaline Iysis and agarose gel electrophoresis techniques were employed to screen these isolates for the presence of plasmid DNA. There were n little differences in the percentage of isolates containing plasmids between sampling sites of unpolluted sen water (22％) and polluted son water (25％). Bacterial isolates taken from the Bunker-C oil enriched culture showed significantly more plasmid incidence (29％). About two thirds of strains grown on a variety of hydrocarbons were Gram negative strains of which 33％ contained one or more plasmids. Multiple plasmids were observed in 23％ of the plasmid-carrying strains. Forty one percent of the plasmids detected were estimated to have a mass of 20 kb or more.

• KSBB Journal
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• v.5 no.3
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• pp.247-253
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• 1990

These studies were carried out to obtain the transformant from carrot cells by using binary vector pGA472 with NPT II gene to confer kanamycin resistance in the plant cells. The binary vector pGA472 was mobilized from E. coli MC1000 into A. tumefaciens strains isolated in the Korea, C23-1. K29-1, and disarmed Ti-plasmid PC2760, and A28l using a tri-parental mating method with E. coli HB101/pRK2013. Transconjugants, C23-1/pGA472, K29-1/pGA472, PC2 760/pGA472 and A28l/pGA472 were obtaind on the minimum AB media containing tetracycline and kanamycin, were comfirmed to hold the Ti-plasmid and pGA472 binary vector on the 0.7% agarose gel. Transformed carrot calli were initiated on the MS media supplemented with l00$\mu\textrm{g}$/ml kanamycin and 250$\mu\textrm{g}$/ml carbenicillin after co-cultivation of carrot explant and transconjugant Agrobacteria. Selected callus was grown vigouousley for subculture on the medium containing 100$\mu\textrm{g}$/ml kanamycin, thus indication that the selected callus was transformed with NPT II gene.

• Microbiology and Biotechnology Letters
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• v.14 no.3
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• pp.219-223
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• 1986

In order to preparr the hybridoma cells which produce a monoclonal antibody to human fibroblast interferon(Hu IFN-$\beta$), spleen cells from BALB/cmice immunized with the purified Hu IFN-$\beta$ were fused with NS-O cells, a myeloma cell line. Forty hybrids with high titer among 1300 hybrids Isolated by an ELISA screening method were subcloned using the soft agarose cloning and limiting dilution methods, and 11 hybrids were selected. As a result of iso-typing the hybrids using the mouse monoclonal typing kit, two hybridomas were found to produce 1gG 2a type of monoclonal an-tibodies. The ascites fluid from nude mice inoculated intraperitoneally with the above hybridomas was removed and purified using a protein A-Sepharose CL-4B. Monoclonal antibody was proven to have only the heavy and light chains on SDS-polyacrylamide gel electrophoresis.

• Research in Plant Disease
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• v.12 no.1
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• pp.62-64
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• 2006

July in 2005, we collected infected maize plant that showing stripe dwarf disease on maize leaf in Jeonbuk provinces including Gochang-gun and conducted genomic dsRNA extraction and RT-PCR. Genomic dsRNA was extracted directly in infected maize plant and electrophoresis in agarose gel. We confirmed 10 segments of genomic dsRNA. We conducted RT-PCR by genomic dsRNA and specific primer of S7, S8 and S10. As a result, specific band of expected size was confirmed respectively. In the results of dsRNA and RT-PCR analysis, we confirmed Rice black-streaked dwarf fijivirus (RBSDV) from naturally infected maize plant. Occurrence of RBSDV of maize plant was dealt 22 ha's damage in maize field. The occurrence rate was 80% in a lot of places of disease.

• Journal of Life Science
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• v.21 no.3
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• pp.468-472
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• 2011

DNA marker is a powerful tool for plant genetics and breeding. In this study, 995 SSR markers were employed with chilling resistant cucumber, known as 'NC76', and chilling susceptible cucumber, known as 'GY14'. Using 2% agarose gel electrophoresis, 145 SSR markers were identified as length variation markers between 'NC76' and 'GY14'. The SSR markers that showed no length polymorphism were then screened using high resolution melting analysis technique and additional 30 polymorphic SSR markers were identified. As a preliminary evaluation for mapping, 20 markers among these 175 markers were employed to a $F_2$ population of 'NC76' x 'GY14' cross. Linkage analysis revealed 13 markers that joined into six linkage groups and seven markers that remained unlinked. This result indicates that these 175 markers could be used for construction of a genetic map using a cross between 'NC76' and 'GY14' for further investigation in developing markers related to resistance to chilling in cucumbers.

• Journal of the korean academy of Pediatric Dentistry
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• v.25 no.2
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• pp.292-303
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• 1998

The arbitrary primer polymerase chain reaction(AP-PCR) and Southern blot restriction fragment length polymorphism(RFLP) were used to genotype the cariogenic pathogen S. mutans in children. Following the morphologic chracteristics of colony on selective medium for S. mutans, total genomic DNA from 155 strains was extracted by conventional methods. Among 155 strains, 143 strains (92.3%) were confirmed S. mutans by PCR with dexA gene and 114 strains were used in this study. Three random sequence 10-base oligonucleotide primers were chosen for AP-PCR. The amplified DNA products were separated electrophoretically in a 2% agarose gel containing ethidium bromide and the banding patterns were compared among different strains. For RFLP analysis, DNA was digested with EcoRI and BamHI, separated on a 0.7 % agarose gel and transferred to a nylon membrane. The membrane was probed with a previously characterised 1.6 kilobases (kb) DNA fragment cloned from gtf B gene of S. mutans. The probe was labeled with isotope[$^{32}P-{\alpha}CTP$], and hybridized fragments were detected with intensifying screen. AP-PCR produced 4-8 DNA bands in the 0.25-10 kb regions and distinguished 9, 10 or 12 genotypes, depending on the specific primer used. Southern blot RFLP analysis revealed 2 hybridization patterns consisting of 1 DNA fragments 450, 500 bp. These results indicate that AP-PCR is more discriminative method for genotyping of S. mutans.