• Korean Journal of Veterinary Research
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• v.43 no.3
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• pp.471-476
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• 2003

Malignant catarrhal fever (MCF) is a systemic disease of ruminants caused by ovine herpesvirus 2 (OvHV-2). OvHV-2 is a gamma herpesvirus, which induces frequent latent infection and often difficult to detect its antigens and even specific nucleic acids because of its low viral copies in the infected tissues. Histopathology, serology and polymerase chain reaction (PCR) were compared for the diagnosis of MCF using 10 bison infected with OvHV-2. Histopathological diagnosis was performed using the criteria which was based upon the pathognomic lesions. Serological diagnosis was conducted using its serum with competitive ELISA for the detection of antibodies of OvHV-2. Also, the nest PCR was performed with peripheral blood leukocytes for the detection of OvHV-2-specific DNAs. Primers 556 and 775 were used for the primary amplification, and primers 556 and 555 were used for the secondary amplification. As the results, positive cases were 6 by histopahology, 9 by serology and 10 by PCR. As comparing with other diagnostic methods, PCR was found to be more sensitive than histopathology and serology. The recent development of molecular diagnostic assays has provided powerful tools for investigating how viruses survive in nature. Development of PCR specific for viruses has dramatically improved the accuracy of diagnosis of viruses in clinically infected animals. Furthermore, amplification of viral genomic material by nest PCR represents the most sensitive method for the detection of viruses and might be detected successfully even though very low viral DNA copies. So, it could be used as the first choice for the detection of viral DNAs with low copies such as the status of latent infection. However, it has also some limitation of application like as false negative results by PCR inhibitors and false positive results by contamination. The results of this study suggest that the use of molecular biological methods like PCR may increase the accuracy for the diagnosis of infectious diseases. However, in diagnostic laboratory, it is recommended that PCR assay must be conducted with other diagnostic methods for more reliable diagnosis.

• Genomics & Informatics
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• v.21 no.4
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• pp.52.1-52.10
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• 2023

Accurate and efficient microbial diagnosis is crucial for effective molecular diagnostics, especially in the field of human healthcare. The gold standard equipment widely employed for detecting specific microorganisms in molecular diagnosis is quantitative real-time polymerase chain reaction (qRT-PCR). However, its limitations in low metagenomic DNA yield samples necessitate exploring alternative approaches. Digital PCR, by quantifying the number of copies of the target sequence, provides absolute quantification results for the bacterial strain. In this study, we compared the diagnostic efficiency of qRT-PCR and digital PCR in detecting a particular bacterial strain (Staphylococcus aureus), focusing on skin-derived DNA samples. Experimentally, specific primer for S. aureus were designed at transcription elongation factor (greA) gene and the target amplicon were cloned and sequenced to validate efficiency of specificity to the greA gene of S. aureus. To quantify the absolute amount of microorganisms present on the skin, the variable region 5 (V5) of the 16S rRNA gene was used, and primers for S. aureus identification were used to relative their amount in the subject's skin. The findings demonstrate the absolute convenience and efficiency of digital PCR in microbial diagnostics. We suggest that the high sensitivity and precise quantification provided by digital PCR could be a promising tool for detecting specific microorganisms, especially in skin-derived DNA samples with low metagenomic DNA yields, and that further research and implementation is needed to improve medical practice and diagnosis.

• Tuberculosis and Respiratory Diseases
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• v.39 no.1
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• pp.1-6
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• 1992

The diagnosis of tuberculosis is usually established using staining and culturing techniques. Fluorescent stains have improved the sensitivity of direct microscopy. Improved culture media coupled with radiometric means of detecting early mycobacterial growth have shortened the time needed for cultural diagnosis. Rapid immunodiagnostic techniques based on the detection of mycobacterial antigen or of antibodies to theses antigens have not, however, come into widespread clinical use. The DNA or RNA hybridization tests with labeled specific probes which have been described so far are not sensitive enough to be used for clinical speicimens without prior culturing. The advent of the polymerase chain reaction (PCR) has opened new possibilities for diagnosis of microbial infections. This technique has already been applied to a number of microorganisms. In the field of mycobacteria the PCR has been used to identify and to detect DNAs extracted from various mycobacteria. However, despite the extraordinary enthusiasm surrounding this technique and the considerable investiment, PCR has not emerged from the developmental "trenches" in the passed several years. It may be a considerable lenth of time before clinical microbiology laboratories become PCR playgrounds because many details remain to be worked out.

• Clinical and Experimental Reproductive Medicine
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• v.32 no.1
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• pp.17-26
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• 2005

Objective: Preimplantation genetic diagnosis (PGD) is reserved for couples with a risk of transmitting a serious and incurable disease, and hence avoids the undesirable therapeutic abortion. In this study, we evaluated the efficacy of PGD for Duchenne muscular dystrophy (DMD) cases by the fluorescent PCR with polymorphic linked markers and the conventional duplex-nested PCR methods. Methods: Biopsy of one or two blastomeres was done from the embryos fertilized by ICSI on the third day after fertilization. We performed two cases of PGD-DMD by the duplex-nested PCR for the causative mutation loci and the SRY gene on Y chromosome. The triplex fluorescent PCR for the mutation loci, the SRY gene and the polymorphic microsatellite marker on X chromosome was applied for two cases of PGD-DMD. Results: By the duplex-nested PCR, successful diagnosis rate was 95.5% (21/22), but we could not discriminate the female embryos whether normal or carrier in this X-linked recessive disease. However, the triplex fluorescent PCR method showed 100% (27/27) of successful diagnosis rate, and all female embryos (n=17) were distinguished normal (n=10) from carrier (n=7) embryos. Unaffected and normal embryos were transferred into mother's uterus after diagnosis. A healthy normal male was achieved after PGD with the duplex-nested PCR method and a twin, a male and a female, were delivered with triplex fluorescent PCR method. The normality of dystrophin gene was confirmed by amniocentesis and postnatal genetic analysis in all offsprings. Conclusion: The fluorescent PCR with polymorphic marker might be useful in improving the specificity and reliability of PGD for single gene disorders.

• Journal of the Korean Chemical Society
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• v.47 no.2
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• pp.127-132
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• 2003

We have developed a direct polymerase chain reaction (PCR) and electrophoresis method for the diagnosis of bovine theileriosis from whole blood DNA analysis without DNA extraction. The technique empolyed a FoLT (formamide, low temp.) technique and was utilized in the diagnosis of bovine theileriosis. Formamide solubilize the blood cells, and the lowered incubation temperatures reduced protein coagulation. 100-200 nL of whole blood and PCR reagents were introduced directly into a PCR tube. After the amplification, the PCR product (816-bp DNA) was introduced into the electrophoresis system. The results of this analysis were consist with those obtained using purified DNA.

• Journal of Veterinary Clinics
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• v.21 no.1
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• pp.35-44
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• 2004

This study was performed to examine the mycological features of canine skin. A total of 50 dogs with skin lesions were examined for dermatology from October, 2000 to April, 2001. The isolation rates of dermatophytes, yeast, filamentous fungi and superficial fungi were 36.4%, 13.5%, 35.3% and 13.6%. The dermatophytes isolated in dogs were Microsporum canins and Trichophyton mentagrophytes were 75% and 25%. The yeast and superficial fungi isolated in dogs were Candida albicans, Rhodntorula minnata, Candida ceferrii and Malassezia spp. were 16.7%. 16.7%, 16.7% and 50%. The filamentous fungi by Aspergillus funigatus, Aspergillus niger, Penicillum spp., Alternaria spp. were 12.5%, 12.5%, 50%, and 25%. In determine if polymerase chain reaction (PCR) could be applied for diagnosis of dermatophytes, yeast and filamentous fungi, control and clinical samples were tested. The size of specific PCR product in agarose gel was 340 bp for dermatophytes and 210 bp for yeast and filamentous fungi, respectively.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.2
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• pp.491-495
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• 2016

Background: Small B-cell non-Hodgkins lymphoma (NHL) is difficult to be distinguished from non-neoplastic reactive processes using conventional haematoxylin-eosin (HE) staining due to different interpretations among pathologists with diagnosis based on morphologic features. Ancillary examinations such as immunohistochemical (IHC) staining are essential. However, negative or doubtful results are still sometimes obtained due to unsatisfactory tissue processing or IHC technique. The polymerase chain reaction (PCR) as a molecular diagnostic technique is very sensitive and specific. Clonality detection of heavy chain immunoglobulin (IgH) gene rearrangement has been widely used to establish diagnosis of B-cell NHL. Aims: To elaborate interobserver variation in small B-cell NHL diagnosis based on morphologic features only and to confirm sensitivity and specificity of the PCR technique as an ancillary method. Materials and Methods: A toptal of 28 samples of small B cell NHL and suspicious lymphoma were interpreted by 3 pathologists in Sardjito General Hospital based on their morphology only. The reliability of assessment and the coefficient of interobserver agreement were calculated by Fleiss kappa statistics. Interpretation results were confirmed with IHC staining (CD20, CD3, Bcl2). PCR was performed to analyze the clonality of IgH gene rearrangement. Results: Interobserver agreement in morphologic evalution of small B cell NHL and chronic lymphadenitis revealed kappa coefficient 0.69 included in the substantial agreement category. The cases were divided into 3 groups based on morphology and IHC results; lymphoma, reactive process and undetermined group. PCR analysis showed 90% sensitivity and 60% specificity. Conclusions: The present study revealed a substantial agreement among pathologists in small B-cell NHL diagnosis. For difficult cases, PCR is useful as complementary method to morphologic and IHC examinations to establish definitive diagnosis.

• Journal of Genetic Medicine
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• v.9 no.1
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• pp.11-16
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• 2012

Purpose: To determine a method to improve the efficacy and accuracy of preimplantation genetic diagnosis (PGD) - polymerase chain reaction (PCR), we compared hot start PCR and conventional multiplex nested PCR. Materials and Methods: This study was performed with single lymphocyte isolated from whole blood samples that were obtained from two couples with osteogenesis imperfecta (OI). We proceeded with conventional multiplex nested PCR and hot start PCR in which essential reaction components were physically removed, and we compared the amplification rate, allele dropout rate and nonspecific products. Afterward, we used selective method for PGD. Results: In the two couples, the respective amplification rate were 93.5% and 80.0% using conventional multiplex nested PCR and 95.5% and 92.0% using hot start PCR. The respective mean allele dropout rates for the two couples were 42.0% and 14.0% with conventional multiplex nested PCR and 36.0% and 6.0% with hot start PCR. Conclusion: The results demonstrate that the hot start PCR procedure provides higher amplification rates and lower allele dropout rate than the conventional method and that it decreased the nonspecific band in multiplex nested PCR. The hot start method is more efficient for analyzing a single blastomere in clinical PGD.

• Journal of Chest Surgery
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• v.33 no.8
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• pp.669-675
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• 2000

Background: Tuberculous pleurisy is the leading cause of pleural effusion in Korea. And differential diagnosis of tuberculous pleurisy with other cause is clinically very important. Traditional diagnostic methods such as routine analysis of pleural fluid, staining for acid-fast bacilli or pleural biopsy have major inherent limitaion. This study was designed to evaluate the significance of pleural fluid polymerase chain reaction(PCR) and adenosine deaminase (ADA) activity in early diagnosis of tuberculous pleurisy. Material and Method: Between March 1996 and July 1997, 198 patients with pleural effusion reviewed retrospectively. The study group included 112 cases with tuberculous effusion and 86 cases with non-tuberculous effusions, whose diagnoses were confirmed by pleural biopsy, microbiological methods, or cytology. We compared the results of PCR and pleural fluid levels of ADA between tuberculous and non-tuberculous effusions. Result: Mean age was 47.54$\pm$19.52 years(range 2 to 85 years). The positive rate of PCR was significantly higher in tuberculous group than non-tuberculous group(p<0.05). The sensitivty, specificity, positive predictive value(PPV), and negative predictive value(NPV) for PCR were 31.7, 90.9, 83.0, and 48.8%, respectively. Mean ADA activity was significantly higher in tuberculous group than non-tuberculous group(83.2 U/L vs 49.8 U/L)(p<0.05). With diagnostic thresholds of 40 U/L, the sensitivity, specificity, PPV, and NPV of ADA for tuberculosis were 75.9, 70.9, 77.3, and 69.3% respectively. At a level of 70 U/L, the sensitivity, specificity, PPV, and NPV of ADA for tuberculosis were 70.1, 75.9, 82.9, and 60.3% respectively. Conclusion: PCR is very highly specific, but less sensitive methods in diagnosis of tuberculous pleurisy. But ADA level of pleural fluid has acceptable sensitivity and specificity in diagnosis of tuberculous pleurisy. ADA activity is more useful test in the evaluation of pleural effusions.

• Korean Journal of Agricultural Science
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• v.38 no.1
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• pp.45-50
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• 2011

This study was conducted to investigate the farm situation about bovine leukemia virus(BLV) infection that greatly influence productivity in dairy cattle and compare the accuracy of diagnosis for BLV infection between PCR and ELISA techniques. Blood samples of 193 heads from 5 herds in Chungnam and Chungbuk area were used to analyze BLV gene and serum, and the results were obtained as follows. The amplified BLV gene in dairy cattle by PCR technique resulted in 226 bp, 596 bp and 434 bp, respectively, for gag, pol and env, which were well amplified. The infection rates of BLV virus diagnosed by PCR and ELISA techniques ranged from 80.55 to 100% and from 22.22 to 86.95%, respectively, and the infection rates among 5 herds were significantly different in both methods (P<0.05). Further, the average infection rates of 5 herds were 87.05 and 63.21%, respectively, for PCR and ELISA techniques. Kappa statistics for examining consistency of diagnosis by PCR and ELISA techniques showed 0.246, which represents low consistency. Consequently, PCR based BLV technique was considered as a corrective measure for diagnosis of BLV infection in Holstein dairy cattle.