• Biomedical Science Letters
• /
• v.7 no.1
• /
• pp.1-5
• /
• 2001

A cDNA of coagulation Factor IX gene has been screened from the $\lambda$gt11 human fetal liver cDNA library, and used to construct a 2.8-kb full length cDNA after recombining with the N-terminal fragment from pTZ-FIX. Human genomic DNA was isolated, digested with the restriction endonucleases, TaqI, EcoRI, and HindIII, and Southern hybridization was performed using the full length factor IX cDNA as a probe. The hybridized bands generated by the restriction endonucleases were the followings: TaqI, 0.3, 1.0, 1.6, 1.8, 2.7, 3.7, and 5.3 kb bands; EcoRI, 1.8, 4.8, 4.9, 5.5, 6.8, and 12.6 kb bands; HindIII, 4.1, 4.4, 5.2, 5.8, 7.6, and 12.5 kb bands. When the Southern bands were physically mapped along the genome, about 50-kb continuous region harboring almost all of the genomic region of Factor Ⅸ gene was covered. These results suggest a possibility of using an exonal cDNA probe to diagnose abnormalities including large deletions, insertions, and rearrangements along the genome, if there is any.

• Korean Journal of Veterinary Research
• /
• v.39 no.1
• /
• pp.148-158
• /
• 1999

The purpose of this study was to establish a rapid, reliable diagnostic method detecting Encephalomyocarditis virus(EMCV) RNA in formalin-fixed, paraffin-embedded tissues of EMCV naturally infected pigs by cDNA probe of EMC $K_3$, the EMCV strain isolated from Korea. Using a biotin-labelled nick translated probe for the cDNA marker. We made up for some defects of radiolabeled method. In sits hybridization(ISH) technique, differently from the other nucleic acid hybridization methods, is able to detect the virus genome specifically in the state of the intact shapes of cells and/or tissues. We succeeded in performing the experiment to detect the EMCV within 1~2 hours using the $MicroProbe^{TM}$ capaillary action system. In this study, we observed highly specific positive signals of red color by staining the paraffin-embedded tissue sections of naturally EMCV-infected pig organs or tissues, including brain, heart, kidney and lacrimal gland with the Fast Red TR salt/Naphtol phosphate chromogen. The results suggested that this ISH method is considered as a highly sensitive and reliable tool for molecular biologic diagnosis of the EMC viral disease.

• Korean Journal of Veterinary Research
• /
• v.34 no.1
• /
• pp.115-125
• /
• 1994

In this study, we try to establish the rapid and specific detection system for Salmonella species. The PhoE gene of Salmonella species was amplified with two specific primers, ST5 and ST8c, using PCR. The probe prepared from the amplified PhoE gene was sequenced and applied for Southern blot analysis. After PCR with ST5 and ST8c primers for PhoE gene, DNA bands of expected size(365bp) from 7 different Salmonella species were detected, but not from 12 enterobacteriaceae and 3 gram positive bacteria. PCR was highly sensitive to detect up to 10fg of purified DNA template and to identify Salmonella species with only 320 heat-lysed bacterial cells. The inhibition of PCR amplification from stool specimen was occurred with 50-fold dilution but disappeared over 100 fold dilution of samples. It was confirmed that the PhoE genes were amplified and cloned with over 97% nacleotide sequence homology of PCR products compared with that of S. typhfmurium LT2. The DNA probe derived from S. typhimurium TA 3,000 showed highly specific and sensitive reaction with PCR products of all tested Salmonella species. These results indicate that PCR was rapid and sensitive detection method for Salmonella species and DNA probe prepared from S. typhimurium TA 3,000 was specific to identify PCR products of different Salmonella species.

• Reproductive and Developmental Biology
• /
• v.28 no.2
• /
• pp.133-137
• /
• 2004

Sexing from bovine embryos which were fertilized in vitro implicate a possibility of the sex-controlled cattle production. This study was carried out to investigate the possibility of determining of embryo sex by fluorescence in situ hybridization (FISH) technique. FISH was achieved in in vitro fertilized bovine embryos using a bovine Y-specific DNA probe which constructed from the btDYZ-1 sequences. To evaluate Y-chromosome specificity of the FISH probe, metaphase spreads of whole embryos and lymphocytes were prepared and tested. A male-specific signal was detected on 100% of Y chromosome bearing metaphase specimens. Using the FISH technique with a bovine Y-specific probe, 232 whole embryos of 8 cell- to blastocyst-stage were analyzed. Observing the presence of the Y-probe signal on blastomeres, 102 embryos were predicted as male, and 130 embryos as female. The determining rate of embryo sex by FISH technique was about 93% regardless of embryonic stages. In conclusion, the FISH using a bovine Y-specific DNA probe is an accurate, reliable and quick method for determining the sex of bovine embryos.

• Journal of Life Science
• /
• v.20 no.12
• /
• pp.1896-1901
• /
• 2010

This study was conducted using quantitative real-time PCR using Lactobacilli as probiotics. Quantitative real-time PCR (RT PCR) was conducted via a method involving SYBR Green 1 and a probe. Plasmid DNA was cloned using the 16S-23S rRNA intergenic species region. Gene clones were diluted from $10^2$ to $10^{10}$. Standard curves were constructed via Ct values obtained from the results of Real-time PCR via the aforementioned SYBR Green 1 and probe method. Plasmid DNA was also cloned using the 16S-23S rRNA intergenic species region and the gene clones were diluted from $10^2$ to $10^{10}$ copy numbers via the probe method. Using RT PCR, a standard curve of plasmid DNA copy numbers was also determined. The slope value for the Y-axis intercept and $R^2$ value were measured as -3.346, 33.18, and 0.993, respectively, via the first method. For the second method, the slope value for the Y-axis intercept and $R^2$ were -3.321, 31.10 and 0.995, respectively. The PCR inhibitor could not express the detection curve at a copy number over $10^{10}$ via either method, owing to high DNA density. The DNA extract from probiotics was diluted without pre-culturing, and 16 products were amplified via both methods. The Ct value was 11.06~18.12 in the first method and 16.74~22.11 in the second method. Measured probiotics and log copy values were largely similar among the methods used. It was concluded that both methods are effective for analysis, but further research will be required to verify the optimal method.

• Animal cells and systems
• /
• v.3 no.1
• /
• pp.73-78
• /
• 1999

Although there are several methods for the preparation of mitochondrial DNA (mtDNA) from mammalian tissues, most are relatively long ultracentrifugation or manipulations by a small-scale method. We escribed a rapid method for large-scale extraction of mtDNA from human placental and horse liver tissues. The method is based on the preparation and homogenization of tissues, urification of crude mitochondria by differential centrifugations and isolation of mtDNA by alkaline Iysis. It was improved from Pre-existing methods by replacing some steps with simpler ones and discarding many others. This method gives a high yield of pure mtDNA(approximately 1-5mg from one placenta; ca. 400-600 g wet weight), depending on its sources (fresh tissue gave better results than frozen one). The resulting mtDNA indicated that this method can yield mtDNA in sufficient purity and quantity to identify the direct restriction analysis on agarose gel, random-primed labeling as a probe, and end labeling. Therefore, the method is ideal for obtaining good mtDNA samples to conduct routine restriction fragment length polymorphism (RFLP) analyses of natural populations for genetic studies.

• Microbiology and Biotechnology Letters
• /
• v.45 no.4
• /
• pp.358-364
• /
• 2017

Asymmetric PCR preferentially amplifies one DNA strand for use in DNA hybridization studies. Linear-After-The-Exponential-PCR (LATE-PCR) is an advanced asymmetric PCR method which uses innovatively designed primers at different concentrations. This study aimed to optimise LATE-PCR parameters to produce single-stranded DNA of Candida spp. and Aspergillus spp. for detection via probe hybridisation. The internal transcribed spacer (ITS) region was used to design limiting primer and excess primer for LATE-PCR. Primer annealing and melting temperature, difference of melting temperature between limiting and excess primer and concentration of primers were optimized. In order to confirm the presence of single-stranded DNA, the LATE-PCR product was hybridised with digoxigenin labeled complementary oligonucleotide probe specific for each fungal genus and detected using anti-digoxigenin antibody by dot blotting. Important parameters that determine the production of single-stranded DNA in a LATE-PCR reaction are difference of melting temperature between the limiting and excess primer of at least $5^{\circ}C$ and primer concentration ratio of excess primer to limiting primer at 20:1. LATE-PCR products of Candida albicans, Candida parapsilosis, Candida tropicalis and Aspergillus terreus at up to 1:100 dilution and after 1 h hybridization time, successfully hybridised to respective oligonucleotide probes with no cross reactivity observed between each fungal genus probe and non-target products. For Aspergillus fumigatus, LATE-PCR products were detected at 1:10 dilution and after overnight hybridisation. These results indicate high detection sensitivity for single-stranded DNA produced by LATE-PCR. In conclusion, this advancement of PCR may be utilised to detect fungal pathogens which can aid the diagnosis of invasive fungal disease.

• KSBB Journal
• /
• v.29 no.5
• /
• pp.361-371
• /
• 2014

Mycoplasma is well recognized as one of the most prevalent and serious microbial contaminants of biologic manufacturing processes. Conventional methods for mycoplasma testing, direct culture method and indirect indicator cell culture method, are lengthy, costly and less sensitive to noncultivable species. In this report, we describe a new TaqMan probe-based real-time PCR method for rapid and quantitative detection of mycoplasma contamination during manufacture of biologics. Universal mycoplasma primers were used for mycoplasma PCR and mycoplasma DNA was quantified by use of a specific TaqMan probe. Specificity, sensitivity, and robustness of the real-time PCR method was validated according to the European Pharmacopoeia. The validation results met required criteria to justify its use as a replacement for the culture method. The established real-time PCR assay was successfully applied to the detection of mycoplasma from human keratinocyte and mesenchymal stem cell as well as Vero cell lines artificially infected with mycoplasma. The overall results indicated that this rapid, specific, sensitive, and robust assay can be reliably used for quantitative detection of mycoplasma contamination during manufacture of biologics.

• BMB Reports
• /
• v.38 no.4
• /
• pp.399-406
• /
• 2005

A sensitive method for detection of Hepatitis A virus (HAV) by utilizing gold-DNA probe on an array was developed. Amino- modified oligodeoxynucleotides at the 5' position were arrayed on an activated glass surface to function as capture probes. Sandwich hybridization occurred among capture probes, the HAV amplicon, and gold nanoparticle-supported oligonucleotide probes. After a silver enhancement step, signals were detected by a standard flatbed scanner or just by naked eyes. As little as 100 fM of HAV amplicon could be detected on the array. Therefore, the array technology is an alternative to be applied in detection of HAV due to its low-cost and high-sensitivity.

• Journal of Genetic Medicine
• /
• v.6 no.2
• /
• pp.146-154
• /
• 2009

Multiplex ligation dependent probe amplification (MLPA) is a PCR-based method to detect gene dosage. Since its introduction, MLPA has been used to test a large number of genes for major deletions or duplications. Genetic testing, as a diagnostic tool for genetic disease, has been used primarily to identify point mutations, including base substitutions and small insertions/deletions, using PCR and sequence analysis. However, it is difficult to identify large deletions or duplications using routine PCR- gel based assays, especially in heterozygotes. The MLPA is a more feasible method for identification of gene dosage than another routine PCR-based methods, and better able to detect deleterious deletions or duplications. In addition to detection of gene dosage, MLPA can be applied to identify methylation patterns of target genes, aneuploidy during prenatal diagnoses, and large deletions or duplications that may be associated with various cancers. The MLPA method offers numerous advantages, as it requires only a small amount of template DNA, is applicable to a wide variety of applications, and is high-throughput. On the other hand, this method suffers from disadvantages including the possibility of false positive results affected by template DNA quality, difficulties identifying SNPs located in probe sequences, and analytical complications in quantitative aspects.