• Asian Pacific Journal of Cancer Prevention
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• v.15 no.24
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• pp.10647-10652
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• 2015

Background: The aim of our study was to establish COLD-PCR combined with an unlabeled-probe HRM approach for detecting KRAS codon 12 and 13 mutations in plasma-circulating DNA of pancreatic adenocarcinoma (PA) cases as a novel and effective diagnostic technique. Materials and Methods: We tested the sensitivity and specificity of this approach with dilutions of known mutated cell lines. We screened 36 plasma-circulating DNA samples, 24 from the disease control group and 25 of a healthy group, to be subsequently sequenced to confirm mutations. Simultaneously, we tested the specimens using conventional PCR followed by HRM and then used target-DNA cloning and sequencing for verification. The ROC and respective AUC were calculated for KRAS mutations and/or serum CA 19-9. Results: It was found that the sensitivity of Sanger reached 0.5% with COLD-PCR, whereas that obtained after conventional PCR did 20%; that of COLD-PCR based on unlabeled-probe HRM, 0.1%. KRAS mutations were identified in 26 of 36 PA cases (72.2%), while none were detected in the disease control and/or healthy group. KRAS mutations were identified both in 26 PA tissues and plasma samples. The AUC of COLD-PCR based unlabeled probe HRM turned out to be 0.861, which when combined with CA 19-9 increased to 0.934. Conclusions: It was concluded that COLD-PCR with unlabeled-probe HRM can be a sensitive and accurate screening technique to detect KRAS codon 12 and 13 mutations in plasma-circulating DNA for diagnosing and treating PA.

• Journal of Food Hygiene and Safety
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• v.25 no.3
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• pp.278-280
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• 2010

This study was aimed to develop a novel qualitative multiplex polymerase chain reaction (PCR) for simultaneous detection of genetically modified (GM) soy and maize within a single reaction. The specific primers designed to detect four respective GM events (A2704-12, MON88017, Bt11, and MON863) were included in the tetraplex PCR system. Each of PCR products for four GM events could be distinguished by agarose gel based on their different lengths. The specificity and reproducibility of this multiplex PCR were evaluated. This multiplex PCR consistently amplified only a fragment corresponding to a specific inserted gene in each of the four GM events and also amplified all four of the PCR products in the simulated GM mixture. These results indicate that this multiplex PCR method could be an effective qualitative detection method for screening GM soy and maize in a single reaction.

• Food Science and Preservation
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• v.15 no.1
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• pp.88-93
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• 2008

This paper focused on the detection of the genetically modified soybean (Glycine max L. MERRILL) samples to search for the speedy analysis methods. We have identified the PCR (polymerase chain reaction) assay with a newly developed technique called DHPLC (denaturing high performance liquid chromatography) to screen the GMO in soybean. The DHPLC is i1s ability to directly detection specific sequences of DNA by using column. With these characteristics. the DHPLC assay had the advantage of simplicity, rapidty could obtain result within 20 minutes. Whereas $15{\times}10^{-4}ng/{\mu}L$ concentration could be detected with the PCR analysis, $15{\times}10^{-5}ng/{\mu}L$ concentration could be detected with the DHPLC method. Therefore, DHPLC method was considered to be a simple, fast and sensitivity screening method rather than PCR analysis for GMO detection in soybean.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.8
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• pp.4533-4537
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• 2013

Objective: To use microarray chip technology for screening of stem cell radiation related miRNAs in laryngeal squamous cell carcinoma; study and explore the relationship of miRNAs with radiosensitivity of laryngeal squamous cells. Method: After conventional culture and amplification of the laryngeal squamous carcinoma cell line Hep-2, CD 133+ cells were screened out with combination of isolated culture of stem cell microspheres and FACS for preparation of laryngeal cancer stem cells. After radiation treatment, miRNAs of laryngeal squamous carcinoma stem cells before and after radiation were enriched and purified. After microarray hybridization with mammalian miRNA and scanning of fluorescence signal, the miRNAs of laryngeal squamous carcinoma stem cells before and after radiation was subject to differential screening and clustering analysis. Real-time quantitative RT-PCR was used to verify part of the differentially expressed miRNAs. Results: 70 miRNAs related to laryngeal cancer stem cell radiation with 2-fold difference in expression were screened out, in which 62 were down-regulated and 8 were up-regulated. Fluorescent quantitative RT-PCR results were consistent with miRNAs chip results. Conclusion: Some miRNAs may be involved in self-regulation with laryngeal squamous carcinoma stem cell radiation.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.2
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• pp.89-95
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• 2006

Potato plants carrying the Ry gene are extremely resistance to a number of potyviruses, but it is not known which variety expressed the resistance. In this investigation, combined classical and molecular techniques were used to identify virus resistance potatoes. Mechanical inoculation of 32 varieties of Korean potato cultivars, with potato virus Y (PVY), induced various symptoms, such as mosaic, yellowing, necrosis, mottle, vein clearing and vein bending. Different virus spreading patterns were observed, such as highly sensitive, moderate and resistant to $PVY^o$ inoculated leaves in different cultivars. From the results of double antibody sandwich-enzyme links immunosorbant assays (DAS-ELISA), coupled with reverse transcription polymerase chain reaction (RT-PCR), Winter valley and Golden valley were found to be highly susceptible and resistant cultivars to $PVY^o$ respectively. TEM was used as a complementary method to conform the localization of the virus in leaf tissues. TEM detect virus particles in Golden valley, where, ELISA and RT-PCR were unable to detect the CP gene. However, the interior part of the tissues was severely deformed in $PVY^o$ infected Winter valley, than Golden valley The Ry gene is involved in an induced response in $PVY^o$ infected Golden valley plants. The methods described in this study could be applied for the screening and development of antiviral potatoes.

• Neonatal Medicine
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• v.25 no.2
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• pp.58-65
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• 2018

Purpose: The purpose of this study is to describe the rate of cytomegalovirus (CMV) virolactia, and the prevalence of breast milk (BM)-transmitted postnatal CMV infection among premature infants after freeze-thawing (FT) and Holder pasteurization (HP) of breast milk. Methods: This is a single-center, retrospective study of 312 infants born at less than 32 weeks of gestation, or with a birth weight less than 1,500 g from January 2013 to June 2017. All infants were screened for CMV-specific immunoglobulin (Ig) G and IgM at birth. Initial CMV specific polymerase chain reaction (PCR) and CMV culture were performed on mothers' BM and babies' urine within the first 21 days of life. FT and HP of BM was used to prevent the transmission of CMV. For the surveillance of postnatal CMV infection, CMV culture and CMV specific PCR of urine from babies were repeated one to two months after the initial screening. Screening for viremia and viruria was performed if postnatal CMV infection was suspected. Results: Among 178 BM samples obtained from mothers of CMV-IgG-seropositive infants, 80 (44.9%) were CMV PCR positive. CMV deoxyribonucleic acid (DNA) was detected in five of the 22 BM samples (22.7%) obtained from the mothers of CMV-IgG seronegative infants. When CMV DNA load in BM was measured before and after HP, various results were shown. Sixty-three infants out of 232 (27.2%) were evaluated for postnatal CMV infection and four infants out of 63 (6.3%) were infected. Conclusion: Interventions to prevent BM-transmitted CMV infection can reduce the chance of postnatal CMV infection, but not completely eliminate it.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.7
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• pp.4209-4214
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• 2013

Background: Breast cancer is among the five most common cancers and ranks first among cancers diagnosed in Iranian women. Screening and treatment of this disease with molecular methods, especially regarding high incidences at early age and advanced stage, is essential. Several genes with altered expression have been identified by cDNA microarray studies in breast cancer, with the Bcl-2 gene indicated as a likely candidate. In this study, we studied Bcl-2 gene expression levels in parallel tumor and non-tumor breast tissues. Materials and Methods: Forty samples including 21 tumor, 16 non tumor (marginal) and 3 benign breast tissues which were all pathologically diagnosed, were subjected to RNA extraction and polyA RT-PCR with the expression level of Bcl-2 quantified using real-time PCR. Results: There is higher expression levels of the Bcl-2 gene in tumor samples compared with marginal samples, but not attaining significance(p>0.05). Bcl-2 expression in 14 (66.7%) of the cases of tumor samples and 9 (56.3%) cases of the marginal samples were positive. Comparison of the expression of the Bcl-2 gene in histological grade showed that a high expression of Bcl-2 was associated with a high histological grade (p<0.41). Conclusions: Our data suggests that dysregulated Bcl-2 gene expression is potentially involved in the pathogenesis of breast cancer. Using gene expression analysis may significantly improve our ability for screening cancer patients and will prove a powerful tool in the diagnosis and prognostic evaluation of the disease whilst aiding the cooperative group trials in the Bcl-2 based therapy project.

• Food Science of Animal Resources
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• v.31 no.5
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• pp.658-662
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• 2011

In this study, 543 samples of press hams, sausages, processed ground meat and processed cheese acquired from retail markets in Seoul and Gyeonggi province in Korea from 2005 to 2010 were monitored using a one-step multiplex polymerase chain reaction (PCR) method that involves the amplification of specific soya or maize endogenous genes and the amplification of 35S promoter (p35S) and nopaline synthase terminator (tNOS) for GMO detection. Among the 543 samples, 477 samples were amplified for maize and/or soybean endogenous genes. Although one sausage sample collected in 2008 showed amplification of tNOS, the result was assumed to be false positive based on the results from further tests of other sausage samples of the same brand. Our results demonstrate the absence of GM soya and/or maze of livestock products in the Korean market during 2005-2010. In addition, the one-step multiplex PCR using previously constructed primer sets appears to be useful as a screening method for the detection of GMOs in processed livestock products. However, more specific methods should be established and employed to detect the event-specific GM gene for positive reaction samples by screening tests in processed livestock products.

• Journal of Microbiology and Biotechnology
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• v.11 no.3
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• pp.394-398
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• 2001

Because of the great concern over the possibility of contamination from the rod-shaped nuclear virus (PRDV) from Japan and white spot virus (WSSV) from Taiwan, most eggs used in Korean shrimp farms are currently obtained from local broodstock. In addition, the screening of imported broodstock for any viral presence at the National Fisheries Research and Development Institute is also mandatory. Nonetheless, massive mortality from white spot syndrome continues in Korea. In the present study, we present an improved PCR method to use tissue-extracted DNA instead of viral DNA extracted from a purified virus based on a sucrose density gradient, and produced results within 8 h. In 1998, this modified PCR method was able to detect that diseased Penaeus japonicus were infected within 8 h. In 1998, this modified PCR method was able to detect that diseased Penaeus japonicus were infected only with PRDV, while Fenneropenaeus chinensis were infected with both PRDV and WSSV. In 1999, PRDV and WSSV were detected in F. chinensis with signs of infection, but not with WSSV alone.

• BMB Reports
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• v.29 no.1
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• pp.52-57
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• 1996

A specific DNA fragment from Korean radish (Raphanus sativus L.) was amplified by performing PCR with oligonucleotide primers which correspond to the highly conserved regions of plant peroxidases. The size of the PCR product was ca. 400 bp, as expected from the known plant peroxidase genes. Comparison of the nucleotide and deduced amino acid sequences of the PCR product to those of other plant peroxidase-encoding genes revealed that the amplified fragment corresponded to the highly conserved region I and III of plant peroxidases. By screening a genomic library of Korean radish using the amplified fragment as a probe, two positive clones, named prxK1 and prxK2, were isolated. Restriction mapping studies indicated that the 5.2 kb Sail fragment of the prxK1 clone and the 4.0 kb EcoRI fragment of the prxK2 clone encode separate isoperoxidase genes. Analyses of the promoter region of the prxK1 clone shows that putative CAAT box, CMT box, and TGA1b binding sequence (5' TGACGT) are present 718 bp upstream from the start codon.