• Korean Journal of Microbiology
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• v.41 no.3
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• pp.168-176
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• 2005

Vibrio vulnificus, one of the marine bacterial pathogens causing septicemia, was detected using molecular methods, namely, PCR and/or Southern hybridization, and real-time PCR. Extracted and purified total DNAs by using commercial kits were used as templates for PCR. Multiplex-PCR was conducted by employing three sets of primers for the genes, hemolysin (vvhA), phosphomannomutase (pmm), and metalloprotease (vvpE), for V vulnificus virulence. The presence of DMSO ($5\%$) and BSA ($0.1\%$) in PCR reaction mixture improved a detection efficiency by higher PCR band intensities. TaqMan real-time PCR was carried out by using gene segment of vvhA as a target. Detection limit of PCR/Southern hybridization without enrichments was to be around $10^2\;cells\;g^{-1}$ of sample. However, those three methods using the enrichment at $35^{\circ}C$ in APW showed high sensitivity ($2\~10\;cells\;g^{-1}$ of sediments). Highly sensitive detection of V vulnificus by real-time PCR was achieved within $5\~6$ hr, whereas the detection by PCR/Southern hybridization required about 36 hr. Thus, it was evident that real-time PCR is the most rapid and efficient method for detecting V vulnificus in tidal flat sediments.

• Korean Journal of Veterinary Research
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• v.39 no.3
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• pp.583-592
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• 1999

We have developed the in situ hybridization(ISH) technique for rapid diagnosis of canine distemper(CD) which is the major infectious disease in dogs. In our experiment, we rapidly detected distribution of the specific canine distemper viral genome without disrupting morphology of tissues or cells. Two oligonucleotide probes for ISH were synthesized chemically and labelled 5' end with nonisotopic biotin by DNA synthesizer. The whole procedures of ISH was completed within 1~2 hours using the Microcapillary action system. On histological study, typical cytoplasmic or intranuclear inclusion bodies were observed in the trachea, bronchiole, brain, and urinary bladder with the presence of prominent red positive signals on ISH, indicating specific CDV genome from the paraffin-embedded tissues of infected 13 cases. The results showed ISH can be used as a rapid and effective diagnostic method for diagnosis of CD.

• Clinical and Experimental Reproductive Medicine
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• v.24 no.3
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• pp.369-375
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• 1997

Studies were conducted to determine the efficiency of decondensation protocols. Sperm obtained from seven normal donors was immediately washed after liquefaction and then decondensed using the method of West et al. (1989) and my original protocol. My optimized protocol entailed mixing 1 ml aliquots of semen with 4 ml phosphate buffered saline (PBS). Following centrifugation, pellets were resuspended in 1 ml PBS containing 6 mM EDTA. After centrifugation, pellets were resuspended in 1 ml PBS containing 2 mM dithiothreitol at $37^{\circ}C$ for 45 min. Following mixing with 2 ml PBS and centrifugation, pellets were resuspended by vortexing. While vortexing, 5 ml of fixative were gently added. Slide preparation was accomplished using the smear method and it was stored at $4^{\circ}C$. When comparing these protocols, the degree of sperm decondensation and head swelling was monitored by measuring nuclear length, area, perimeter, and degree of roundness using FISH analysis software. Apparent copy number for chromosome 1 and, separately, for the sex chromosomes was determined by FISH using satellite DNA probes for loci DIZ1, DXZ1 and DYZ3. Sperm treated by my decondensation protocol showed significant increases (p<0.05) in length, area, perimeter, and degree of roundness. There was a significant decrease (p<0.05) in the frequency of nuclei displaying no signal but no change in the frequency of nuclei with two signals in samples decondensed by my protocol. My data suggested that decondensation using my original protocol may lower the frequency of cells with spurious "nullisomy" due to hybridization failure without inducing spurious "disomy" resulting from increased distances between split signals.

• Korean Journal of Veterinary Research
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• v.36 no.4
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• pp.859-871
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• 1996

This study was conducted to elucidate the distribution of Aujeszky's disease viral nucleic acids and antigens in the central nervous system (CNS) of piglets. The first Korean isolate of Aujeszky's disease virus(ADV) that isolated from naturally infected piglets in Yang San, was inoculated into 32 day old piglets with $10^{5.9}TCID_{50}/ml$ through intranasal or intramuscular route. These piglets were sacrificed at every 24hrs for 8 days. The immunohistochemistry (IHC) was conducted to detect the viral antigens in paraffin-embedded tissue sections using avidin-biotin-peroxidase complex (ABC) method. The viral nucleic acids were detected by in situ hybridization (ISH) using ADV specific DNA probe labeled with digoxigenin. The ADV antigens were detected in reticuloendothelial cells of spleen, lymph nodes and tonsil, alveolar walls, leptomeningeal vascular walls, inflammatory foci of each organ, and nerve cells. The viral nucleic acids were detected in the spinal trigeminal nucleus and its tracts of the pons and medulla oblongata by the ISH technique. The pathways of AD viruses in CNS were determined by IHC and ISH. In the intranasally inoculated group, the viruses in nasal mucosa moved to medulla oblongata and pons through the trigeminal nerve. In case of intramuscullarly inoculated group, viruses moved to brain via lymphoid organs or spinal nerves from sciatic nerves.

• Journal of fish pathology
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• v.6 no.2
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• pp.93-101
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• 1993

The RNAI mutation of Saccharomyces cerevisia is a recessive and temperature sensitive lethal mutation which interferes with the production of mRNA, rRNA, and tRNA. However, the precise role of RNAI gene have not been revealed until yet. We have cloned rna1-1 mutant gene from rna1-1 mutant yeast strain(R49 ; trpl, ura3-52, rna1-1). The 3.4kb BglII fragment of wild type RNAI clone(81-2-6) contains whole RNAI gene. The genomic southern blotting with BglII digested R49 genomic DNA as a probe shows the unique and identical band with wild type 3.4kb BglII fragment. Therefore, We prepared partial BglII genomic library(3~4kb BglII fragments) into BamH I site of pUC19. The rna 1-1 mutant clone was screened with Digoxigenin(DIG)-lableled probe by high density colony hybridization. The 5'-flanking region of rna1-1 gene was sequenced by dideoxy chain termination method. The 5'-flanking sequence of RNAI gene contains three TATA-like sequence ; TAATA, TATA and TTTTAA at position of -67, -45, and -36 from first ATG codon respectively. The 5'-flanking region of wild type RNA I gene from ATG codon to -103nt was deleted with Bal31 exonuclease digestion, generating $pUC{\Delta}$/RNA I. After constructing $pYEP{\Delta}RNA$ I (consists of -103nt deleting RNA I gene, URA3 gene, $2{\mu}m$ rep. origin), pYEPrna1-1(consists of Xba I fragment of pUCrna1-1. URA3 gene, $2{\mu}m$ rep. origin), and pYEPRNAI. each plasmid was transformed into host strain(trpl, ura3-52, rna1-1) by electroporation, respectively. Yeast transformant carrying $pYEP{\Delta}RNA$ I did not complement the thermal sensitivity of rna1-1 gene. It means that TATA-like sequences in 5'-flanking region is not TATA sequence for transcribing RNAI gene and there may be other essential sequence in upstream region for the transcription of RNAI gene.

• Journal of Life Science
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• v.17 no.3 s.83
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• pp.386-395
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• 2007

A total of 27 strains of Vibrio parahaemolyticus (18 strains isolated from Korea and 9 strains from Japan) were serotyped and examined for biochemical characteristics, antimicrobial susceptibility patterns, cytotoxicity assay, thermostable direct hemolysin (TDH) production and molecular epidemiology. Using polymerase chain reaction (PCR) method and DNA probe hybridization method, the strains were tested for toxR, tdh, trh and ORF 8 genes. The V. parahaemolyticus isolated from patients were belonged to 8 different serotypes : O3:K6, O1:K38, O3:K57, O4:K9, O4:Kl2, O4:K68, O5:Kl5 and O6:K46. Urease-positive strain possessed the trh gene, and conversely, urease-negative strains lacked the gene, indicating that urease production by V. parahemolyticus strains strongly correlates with the possession of the trh gene. Most strains showed multiple resistant to more than three antibiotics and the antibiogram could be classified into 6 group (I to VI). All of the O3:K6 strains isolated in South Korea and Japan producted TDH at high levels. The TDH titers ranged between 256 and 2.048, and the average titer was 1009. To distinguish the new and increasingly common V. parahaemolyticus strains from clinical isolates, ORF 8 is a useful genetic marker. After Southern hybridization, the HindIII restriction fragment patterns of the tdh gene were grouped one type, respectively. One type showed two bands one of which was 4.3kb and the other was 11.5kb in size. Variation between the O3:K6 serotype are minor when compared to the differences seen with the non O3:K6 strains. The migration patterns of Not I -digested of the total DNA of the O3:K6 strains were similar, and only slight variations were observed between the serotypes. By contrast, the O3:K6 strains and non O3:K6 had markedly different profiles. In conclusion, Random amplified polymorphic DNA (RAPD) profile using appropriate primers was an effective epidemiological marker.

• Microbiology and Biotechnology Letters
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• v.30 no.1
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• pp.15-20
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• 2002

Diacylglycerol kinase (DGK) phosphorylates the second messenger diacylglycerol (DAG) to phosphatidic acid and it may play a role in signal transduction in Escherichia coli as well as in eukaryotic cells. In addition, DGK is important for microorganisms to adapt to several physiological stimuli. In Bacillus subtilis, the effect of stress on dgk transcription was examined by northern hybridization. The high level of dgk transcription was induced against high osmolarity, low pH value and low temperature. Transcriptional analysis revealed that the dgk gene and dgk upstream locus (ORF2, ORF3 and ORF4) were transcribed as a polycistronic mRNA to form an approximately 2.5 kb transcript.

• Journal of the Optical Society of Korea
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• v.10 no.3
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• pp.130-142
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• 2006

Lab-on-a-chip technology is attracting great interest because the miniaturization of reaction systems offers practical advantages over classical bench-top chemical systems. Rapid mixing of the fluids flowing through a microchannel is very important for various applications of microfluidic systems. In addition, highly sensitive on-chip detection techniques are essential for the in situ monitoring of chemical reactions because the detection volume in a channel is extremely small. Recently, a confocal surface enhanced Raman spectroscopic (SERS) technique, for the highly sensitive biological analysis in a microfluidic sensor, has been developed in our research group. Here, a highly precise quantitative measurement can be obtained if continuous flow and homogeneous mixing condition between analytes and silver nano-colloids are maintained. Recently, we also reported a new analytical method of DNA hybridization involving a PDMS microfluidic sensor using fluorescence energy transfer (FRET). This method overcomes many of the drawbacks of microarray chips, such as long hybridization times and inconvenient immobilization procedures. In this paper, our recent applications of the confocal Raman/fluorescence microscopic technology to a highly sensitive lab-on-a-chip detection will be reviewed.

• Development and Reproduction
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• v.17 no.3
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• pp.215-220
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• 2013

Recently, the RNA/DNA-binding protein FUS, Fused in sarcoma, was shown to play a role in growth, differentiation, and morphogenesis in vertebrates. Because little is known about Fus, we investigated its expression pattern in murine tooth development. In situ hybridization of mouse mandibles at specific developmental stages was performed with a DIG-labeled RNA probe. During early tooth development, Fus was detected in the dental epithelium and dental mesenchyme at 11 days postcoitum (dpc) and 12 dpc. From 14 dpc, Fus was strongly expressed in the dental papilla and the cervical loop of the dental epithelium. At postnatal day 4 (PN4), Fus expression was observed in the odontoblasts, ameloblasts, the proliferation zone of the pulp, and the cervical loop. At PN14, the expression pattern of Fus was found to be maintained in the odontoblasts and the proliferation zone of the pulp. Furthermore, Fus expression was especially strong in the Hertwig's epithelial root sheath (HERS). Therefore, this study suggests that Fus may play a role in the HERS during root development.

• Journal of Life Science
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• v.14 no.6 s.67
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• pp.1018-1022
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• 2004

Optimized conditions for Agrobacterium-mediated lisianthus pollen transformation were adjusted using various factors such as temperature, pH and sucrose concentration. Pollen tube growth was successfully achieved in a medium (pollen germination medium; PGM) containing $7-15\%$ sucrose with pH in the range of 5.5-7.0 at temperature of $20-27^{\circ}C$. Lisianthus pollen was vacuum-infiltrated with Agrobacterium cell suspension for 20 min, and transformed pollen was confirmed by GUS histochemistry and Southern hybridization following RT-PCR. Transgenic pollen system may be utilized for establishing an area of plant transient expression systems based on the convenient pollen transformation procedure presented in here.