• Animal Bioscience
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• v.34 no.12
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• pp.1995-2002
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• 2021

Objective: Detection of adulteration in processed meats is an important issue for some countries due to substitution of beef with a cheaper source of protein like poultry. In this study, the presence of chicken meat was investigated using real-time polymerase chain reaction (real-time PCR) and enzyme-linked immunosorbent assay (ELISA) techniques to verify adulteration of fermented sausage samples. Methods: A total of 60 commercial samples were collected from 20 establishments in three replicates including 10 fermented sausage manufacturers and 10 butchers to investigate the presence of chicken meat with the sequential use of real-time PCR and ELISA techniques. In addition, pH, moisture content, water activity and color values of the samples were determined. Results: Both real-time PCR and ELISA showed agreement on the presence or absence of chicken meat in 55 out of 60 fermented sausage samples and chicken meat was identified with both methods in 16 samples. Five samples produced inconsistent results for the presence of chicken meat in the first run. Nevertheless, the presence of chicken meat was verified with both methods when these samples were analyzed for the second time. In addition, the average physico-chemical values of the fermented sausage samples tested positive for chicken meat were not significantly different from some of those fermented sausage samples tested negative for the chicken meat. Conclusion: The sequential use of real-time PCR and ELISA techniques in fermented sausages could be beneficial for the government testing programs to eliminate false negatives for detection of adulteration with chicken meat. Furthermore, consumers should not rely on some of the quality cues including color to predict the adulteration of fermented sausages with chicken meat since there were no statistical differences among some of the samples tested positive and negative for chicken meat.

• Biomedical Science Letters
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• v.6 no.2
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• pp.141-149
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• 2000

The etiologic agents of haemorrhagic fever with renal syndrome (HFRS) in Korea are Hantaan and Seoul virus in the genus Hantavirus, family Bunyaviridae. Antibody titers of sera from HFRS patients against Hantaan virus were measured by immunofluorescent antibody technique (IFAT), enzyme-linked immunosorbent assay (ELISA), high density composite particle agglutination (HDPA) and plaque reduction neutralization test (PRNI). PRNT and nested reverse transcriptase polymerase chain reaction (nested RT-PCR) was used for serotypic differentiation of Hantaviruses against Hantaan and Seoul virus. Eight doubtful HFRS patients showed higher fluorescent, IgG ELISA, agglutination and neutralizing antibody titer by IFAT, ELISA IgG, HDPA and PRNT, respectively Five out of them showed high IgM antibody titer by IgM capture ELISA against Hantaan virus, remarkably. Fifteen HFRS patients showed higher fluorescent antibody titer by IFAT. In PRNT, 12 out of them showed high neutralizing antibody titer against HTNV, 2 against SEOV and 1 against both viruses. In nested RT-PCR using serotype specific-primer, 3 out of them showed positive against HTNV and 1 against SEOV.

• Parasites, Hosts and Diseases
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• v.52 no.4
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• pp.377-381
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• 2014

Microscopy is considered as the gold standard for malaria diagnosis although its wide application is limited by the requirement of highly experienced microscopists. PCR and serological tests provide efficient diagnostic performance and have been applied for malaria diagnosis and research. The aim of this study was to investigate the diagnostic performance of nested PCR and a recently developed an ELISA-based new rapid diagnosis test (RDT), NovaLisa test kit, for diagnosis of malaria infection, using microscopic method as the gold standard. The performance of nested-PCR as a malaria diagnostic tool is excellent with respect to its high accuracy, sensitivity, specificity, and ability to discriminate Plasmodium species. The sensitivity and specificity of nested-PCR compared with the microscopic method for detection of Plasmodium falciparum, Plasmodium vivax, and P. falciparum/P. vivax mixed infection were 71.4 vs 100%, 100 vs 98.7%, and 100 vs 95.0%, respectively. The sensitivity and specificity of the ELISA-based NovaLisa test kit compared with the microscopic method for detection of Plasmodium genus were 89.0 vs 91.6%, respectively. NovaLisa test kit provided comparable diagnostic performance. Its relatively low cost, simplicity, and rapidity enables large scale field application.

• The Plant Pathology Journal
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• v.16 no.1
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• pp.48-51
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• 2000

Citrus tristeza virus (CTV) was identified form CTV-infected early satsuma mandarin (Citus unshiu) and yuzu (C.junos) by RT-PCR. The total RNAs were isolated from citrus bark and seaf tissues infected with CTV and reverse transcription was followed with primers designed for amplifying CTV coat protein gene. DNA fragments 738 bp were amplified by RT-PCR and these products were colned for sequence analysis. Based on the sequence analysis, this PCR product has 97% sequence homology to CTV (T-385) CP gene isolated from USA. RT-PCR assay for CTV detection was more sensitivity than ELISA assay which was done with anti-CTV CP antibody. This is the frist report about CTV identification in Cheju island Korea.

• Korean Journal of Veterinary Research
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• v.40 no.1
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• pp.56-62
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• 2000

Pasteurella multocida is kind of commensal bacteria in the upper respiratory tract of pigs. It is classified toxigenic and nontoxigenic strains based on the production of dermonecrotic toxin. Toxigenic strain is most associated with atrophic rhinitis which brings great economical loss in swine industry. However, toxigenic and nontoxigenic strains do not differ by diagnostic biochemical reaction or morphology. One of recently developed techniques, PCR detects the toxigenic P multocida. Amplification of an 846-nucleotide fragment of toxA gene was developed. The fragment amplified by PCR was detected in P multocida type D not type A. The PCR amplification was as sensitive as it could detect 1 pg of P multocida DNA. We compared the result of the PCR with the enzyme linked immunosorbent assay (ELISA) in a test for 40 swine nasal swabs. All of these isolates were toxin negative based on the ELISA while 2 isolates were detected in the PCR technique. in addition to accuracy, as required for rapid detection from contaminated nasal swabs, toxigenic P multocida was recovered efficiently from contaminated culture without inhibition of the PCR. The results show that the PCR detection of toxigenic P multocida directly form nasal swabs are feasible.

• Annals of Laboratory Medicine
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• v.39 no.1
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• pp.50-57
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• 2019

Background: The Automated Fluorescent Immunoassay System (AFIAS) rotavirus assay (Boditech Med Inc., Chuncheon, Korea) is a new rapid antigen test for rotavirus detection. We evaluated the performance of this assay for detecting rotaviruses and their specific genotypes in clinical stool samples. Methods: AFIAS rotavirus assay was performed in 103 rotavirus-positive and 103 rotavirus-negative stool samples (confirmed by both PCR and ELISA), and its results were compared with those of PCR, ELISA, and immunochromatographic assay (ICA). We evaluated diagnostic sensitivity/specificity, the detectability of rotavirus subtypes, lower limit of detection (LLOD), reproducibility, cross-reactivity, and interference of AFIAS rotavirus assay. Results: Based on PCR and ELISA results, diagnostic sensitivity and specificity of the AFIAS rotavirus assay were both 99.0%. LLOD results showed that the AFIAS assay had sensitivity similar to or greater than ICA and ELISA. High reproducibility was confirmed, and no cross-reactivity or interference was detected. This assay could detect genotypes G1P[8], G2P[4], G3P[8], G4P[6], G4P[8], G8P[4], G8P[8], G9P[4], and G9P[8]. Conclusions: The AFIAS rotavirus assay showed high reproducibility, sensitivity, and specificity as well as excellent agreement with ELISA, PCR, and ICA. It detected the most common as well as unusual genotypes of rotavirus prevalent in Korea. It could be a useful onsite assay for rapid, convenient, and cost-effective detection of rotavirus infection.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.3
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• pp.253-255
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• 1999

Reverse transcription and polymerase chain reaction (RT-PCR) assay was used to detect SMV strains. A pair of oligonucleotide primers were designed to include the cylindrical inclusion (CI) coding region between 4,176 to 5,560 nt. Amplification from the total RNA extracted from infected plants with SMV yielded a 1,385 bp DNA fragment. RT-PCR was shown to be $10^3$ times more sensitive than the ELISA assay and it could detect a virus in $10^{-6}$ dilution. Restriction enzyme analysis of RT- PCR products using EcoR I showed that SMV isolates were classified into six groups according to the patterns of restriction fragments.

• Biomedical Science Letters
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• v.21 no.1
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• pp.9-14
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• 2015

Mouse hepatitis virus (MHV) is a major pathogen in laboratory mice that usually leads to fatal diseases, such as hepatitis, multiple sclerosis, encephalitis, and respiratory disease. MHV has a high infection rate, and it needs to be detected as soon as possible to prevent its spread to other facilities. However, MHV detection by enzyme-linked immunosorbent assay (ELISA) often gives false positives; thus, it is very important that the results are confirmed as true positives in the early infection stage or distinguished as false positives with more accurate, reliable methods. Under microbiological screening, MHV ELISA-positive mice were found in four GFP-tagging transgenic mice. To verify the detection of the MHV antigen directly, reverse transcription polymerase chain reaction (RT-PCR) was performed, and the mice were determined to be MHV negative. Additional serum antibody-based screening was conducted with three different ELISA kits, and multiplexed fluorometric immunoassay (MFIA) was performed to confirm their accuracy/sensitivity. In brief, the ELISA kit for A59 nucleocapsid protein (MHV-A59N) revealed MHV ELISA positivity, while other ELISA kits (MHV-S lysate and MHV-JHM lysate) demonstrated MHV negativity. In MFIA, only the test for the recombinant A59 nucleocapsid antigen was MHV positive, which was consistent with the ELISA results. These results suggest that the ELISA kit with the recombinant A59 nucleocapsid antigen might induce non-specific MHV ELISA positivity and that confirmation is therefore essential.

• Korean Journal of Veterinary Service
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• v.36 no.1
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• pp.31-36
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• 2013

Mycobacterium avium subsp. paratuberculosis is the pathogen of paratuberculosis called Johne's disease. Johne's disease is hardly eliminated because of its long latent period and continuous dissemination, so it is found in ruminants worldwide and can cause substantial economic losses in cattle. It has been reported in many studies on the distribution of Johne's disease in some provinces of Korea that not many, but noticeable numbers of infected cows have been detected since the first detection in 1984. The aims of this study was to investigate the prevalence of Johne's disease obtained from slaughtered cattle in central area of Gyeongnam province, Korea. In this study, the ELISA serum antibody test and PCR were employed on a total of 240 blood and ileac substrate samples from slaughtered cattle in two slaughtering and wholesale centers in Gyeongsangnam-do Livestock Veterinary Research Institute Central Branch. Out of the entire 240 blood samples, three (1.3%) were positive by ELISA, while five (2.1%) were suspected cattle. But ileac substrate samples, eight (3.3%) were positive by PCR. By breeds, positive rates of ELISA and PCR in Korean native cattle were 1.3% and 3.5%, respectively, but no positive cows were found in dairy cattle. By provinces, sero-positive rates of Gyeongnam and Gyeongbuk were 1.6% and 1.3%, respectively. And PCR positive rates of Gyeongnam, Gyeongbuk and other provinces were 2.4%, 5.0% and 2.8%, respectively. These results indicate that it requires the nationwide monitoring test and measure to deal with subclinically infected slaughtering cows.

• Korean Journal Plant Pathology
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• v.13 no.4
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• pp.219-224
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• 1997

A PT-PCR (reverse transcription-polymerase chain reaction) diagnostic method for potato virus Y (PVY) was developed using primer pair derived from conserved region of coat protein genes of several PVY strains, A 764 bp PCR product was detected from several lines of potato cv. Atlantic. We could prove that the 764 bp DNA fragment was indeed the PVY gene by sequencing analysis. PVY detection method using RT-PCR technique was about tuber tissue.