• Annals of Laboratory Medicine
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• 제38권6호
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• pp.578-584
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• 2018

Background: Accurate, rapid, and cost-effective screening tests for hepatitis B virus (HBV) and hepatitis C virus (HCV) infection may be useful in laboratories that cannot afford automated chemiluminescent immunoassays (CLIAs). We evaluated the diagnostic performance of a novel rapid automated fluorescent lateral flow immunoassay (LFIA). Methods: A fluorescent LFIA using a small bench-top fluorescence reader, Automated Fluorescent Immunoassay System (AFIAS; Boditech Med Inc., Chuncheon, Korea), was developed for qualitative detection of hepatitis B surface antigen (HBsAg), antibody to HBsAg (anti-HBs), and antibody to HCV (anti-HCV) within 20 minutes. We compared the diagnostic performance of AFIAS with that of automated CLIAs-Elecsys (Roche Diagnostics GmbH, Penzberg, Germany) and ARCHITECT (Abbott Laboratories, Abbott Park, IL, USA)-using 20 seroconversion panels and 3,500 clinical serum samples. Results: Evaluation with the seroconversion panels demonstrated that AFIAS had adequate sensitivity for HBsAg and anti-HCV detection. From the clinical samples, AFIAS sensitivity and specificity were 99.8% and 99.3% for the HBsAg test, 100.0% and 100.0% for the anti-HBs test, and 98.8% and 99.1% for the anti-HCV test, respectively. Its agreement rates with the Elecsys HBsAg, anti-HBs, and anti-HCV detection assays were 99.4%, 100.0%, and 99.0%, respectively. AFIAS detected all samples with HBsAg genotypes A-F and H and anti-HCV genotypes 1, 1a, 1b, 2a, 2b, 4, and 6. Cross-reactivity with other infections was not observed. Conclusions: The AFIAS HBsAg, anti-HBs, and anti-HCV tests demonstrated diagnostic performance equivalent to current automated CLIAs. AFIAS could be used for a large-scale HBV or HCV screening in low-resource laboratories or low-to middle-income areas.

• 수면정신생리
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• 제4권1호
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• pp.89-95
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• 1997

The authors studied 5 cases of idiopathic CNS hypersomnia who visited Division of Sleep Studies, Seoul National University Hospital in 1995. Detailed medical history was taken and nocturnal polysomnography(NPSG), multiple sleep latency test(MSLT) and human leukocyte antigen(HLA) typing were performed. Neither cataplexy nor hypnagogic hallucination was reported in all cases and in NPSGs, there were tendencies of increased sleep period time and decreased slow wave sleep time. In MSLT, all the subjects showed average sleep latencies less than 8 minutes without sleep-onset rapid eye movement period(SOREMP). In HLA typing, some correlation between idiopathic CNS hypersomnia and HLA DR4 was observed. In contrast to previous reports, overall treatment response with methylphenidate was remarkable. Therefore, the authors suggest that patients suspected of idiopathic CNS hypersomnia be actively evaluated and treated with rather optimistic perspective.

• 한국동물위생학회지
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• 제32권2호
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• pp.147-153
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• 2009

Salmonella species are the most important etiologic agents of food-borne acute gastroenteritis. The most common serotypes isolated from humans are Salmonella enterica serotype Typhimurium (S. Typhimurium) and S. Enteritidis. Traditional detection methods for Salmonella are based on cultures using selective media and characterization of suspicious colonies by biochemical and serological tests. These methods are generally time-consuming and not so highly sensitive. Recently, the polymerase chain reaction (PCR) has been used as a highly sensitive, specific, and rapid test for the presence of pathogenic bacteria. In this study, a multiplex PCR (m-PCR) was used to detect S. Typhimurium and S. Enteritidis. We selected m-PCR target genes, which were the spv (virulence plasmid specific for S. Enteritidis) and sefA (S. Enteritidis fimbrial antigen) genes, fliC (H1-i antigen specific for S. Typhimurium) and a randomly cloned sequence specific for the genus Salmonella. With m-PCR, random sequence was detected from all strains of Salmonella spp, spv and sefA were detected from all strains of S. Enteritidis (100%), and fliC was detected from all strains of S. Typhimurium (100%). This assay indicate that the specificity of the m-PCR make them potentially valuable tools for detection of S. Typhimurium and S. Enteritidis.

• Parasites, Hosts and Diseases
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• 제59권1호
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• pp.9-14
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• 2021

Toxoplasma gondii seroprevalence have been rapidly increasing in some parts of Korea. We analyzed prevalence of anti-Toxoplasma gondii antibodies, using a rapid diagnostic test (RDT), in the sera of 552 residents in Ganghwagun, 661 ones in Cheorwon-gun, and 305 ones in Goseong-gun, Korea in 2019. IgG/IgM RDT mounted with recombinant fragment of major surface antigen (SAG1), glutathione-S-transferase-linker-SAG1A, were applied to the sera. IgG seroprevalence was 28.1% in Ganghwa-gun, 19.5% in Cheorwon-gun and 35.7% in Goseong-gun. Odds ratios comparing Cheorwon vs Ganghwa was 0.63 (P=0.001) and Goesong versus Ganghwa was 1.47 (P=0.01) adjusting age and sex. Goseong had highest seroprevalence among the 3 counties both in crude rates and logistic regression. Although Cheorwon and Goseong are adjacent to the demilitarized zone (DMZ) in Korea, seroprevalence rate was much higher in Goseong. Further investigation on other DMZ-closed areas is necessary whether they have high prevalence rates compared to the other areas. T. gondii prevalence in Korea is still persists; proper health policy should be established.

• 분석과학
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• 제17권3호
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• pp.211-216
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• 2004

본 연구는 분변 잠혈 검출 키트 (one-step FOB(Fecal Occult Blood) kit)가 법생물학적으로 매우 중요한 혈흔 검출 및 사람 혈흔 판정에 적용 가능한지 알아보고자 하였다. 먼저 FOB 키트의 민감도를 결정하고 기존의 혈흔 검사법인 LMG 검사와 비교한 결과 1,000,000배 희석된 혈액까지도 검출 되었는데 이는 LMG 검사에 비해 약100배 정도 예민한 것이었다. 다른 동물 혈액에 대한 교차 반응 여부를 실험한 결과 FOB 키트는 사람의 혈액과만 반응하여 높은 특이성을 보여주었다. 또한 혈액의 보관 온도 및 경과 시간의 영향, 고온 처리의 영향을 알아보았으며, LMG 및 Luminol 시약의 영향에 대해서도 실험하였다. 사람 혈액 특이 항원은 매우 높은 안정성을 보여주었으며, 전통적인 혈흔 검사 시약인 LMG 및 Luminol에 대해서도 영향을 받지 않았다. 따라서 FOB 키트는 LMG 검사 및 Luminol 검사와 병행하여 사용하면 보다 신속하고 정확하게 사람 혈흔 여부를 판정할 수 있어 법과학 실험실에서는 물론 사건 현장에서의 혈흔 검사에 크게 기여할 수 있을 것으로 사료된다.

• 한국미생물·생명공학회지
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• 제46권3호
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• pp.269-276
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• 2018

Rabies virus (RABV)-specific antibodies in animals and humans are measured using standard methods such as fluorescent antibody virus neutralization (FAVN) tests and rapid fluorescent focus inhibition tests, which are based on cell culture systems. An alternative assay that is safe and easy to perform is required for rapid sero-surveillance following mass vaccination of animals. Two purified monoclonal antibodies (4G36 and B2H17) against RABV were selected as capture and detection antibodies, respectively. A genetically modified RABV, the ERAGS strain, was propagated and concentrated by polyethylene glycol precipitation. Optimal conditions for the RABV antigen, antibodies, and serum dilution for a blocking enzymelinked immune sorbent assay (B-ELISA) were established. We evaluated the sensitivity, specificity, and accuracy of the B-ELISA using serum samples from 138 dogs, 71 raccoon dogs, and 25 cats. The B-ELISA showed a diagnostic sensitivity of 95.8-96.3%, specificity of 91.3-100%, and accuracy of 96.0-97.2% compared to the FAVN test. These results suggest that the B-ELISA is useful for sero-surveillance of RABV in dogs, raccoon dogs, and cats.

• Parasites, Hosts and Diseases
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• 제55권3호
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• pp.247-254
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• 2017

ELISA has been used for the diagnosis of toxoplasmosis, but it is being gradually replaced by a rapid diagnostic test (RDT). We compared and analyzed ELISA and RDT results using the sera collected during 4 consecutive years from residents of Gyodong-do (Island), Incheon-city, Korea. Sera from 921, 993, 940, and 838 adult residents were collected on a yearly basis (2010-2013). ELISA was performed by using a crude extract of T. gondii RH strain antigen and IgG/IgM RDT mounted with recombinant fragment of major surface antigen (SAG1), GST-linker-SAG1A, were applied to the sera. Comparison between groups was analyzed by the Student's t-test. The positive seroprevalence surged from 14.7% (135/921, 2010), 23.1% (231/993, 2011), 23.6% (222/940, 2012), and 32.1% (269/838, 2013) by ELISA. In contrast, RDT showed a more moderate increasing trend from 21.7% (200/921, 2010), 25.5% (253/993, 2011), 28.9% (272/940, 2012) and 33.1% (277/838, 2013). Discrepancies between ELISA and RDT were noted near the cut-off value. At the OD 0.15-0.24 range, RDT could detect 16.1% (169/1051) more positives, which suggests an early or acute toxoplasmosis, but at the OD 0.25-0.34 range, ELISA could detect 35.9% (92/256) more positives of possible chronic infections. Over the OD > 0.35 ELISA and RDT agreed in the majority of the cases. This surge in seroprevalence may be caused by the organic agriculture in addition to eating behavior or increase in pets among Koreans. These facts may be applied on a full-scale national survey using RDT to supplement ELISA to define the characteristics of the infection.

• 한국수의병리학회지
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• 제1권2호
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• pp.119-124
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• 1997

The objective of this study was to develop digoxigenin (DIG)-labeled in situ hybridization (ISH) test for diagnosis of Aujeszky's Disease(AD) in infected organs. Specific DNA with well conserved gene sequences encoding gp50 antigen in AD virus (ADV) was obtained by Polymerase Chain Reaction (PCR) method. A pair of oligonucleotide primers used in PCR allowed amplification of a 217 bp sequence from the gp50 ADV gene. The DNA was then labeled with DIG by primer labeling method for use as probe in ISH test to detect ADV nucleic acids in various tissue. Positive hybridization was demonstrated by dark pigmentation in nuclei and cytoplasm of ADV infected cells particularly in brain tonsillar crypt epithelium and pulmonary alveolar cells. This result suggests that ISH is a valuable sensitive and rapid diagnostic test for AD.

• Animal cells and systems
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• 제7권1호
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• pp.89-92
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• 2003

Immunoassays have become indispensable tools and achieved great importance in scientific and medical research. However, typical immunoassays are time-consuming and use complex, multi-step procedures. In this study, we introduce a new immunoassay system for the quantification of several analytes at a time without any washing steps. It is comprised of a detector solution with fluorescence-labeled antibodies and a test strip with immobilized capture antibodies. Using a micro-array scanner, the antigen-antibody complex was quantitatively determined by measuring the intensities of fluorescence on the capture lines or dots of nitrocellulose membrane. This method demonstrated its rapid quantitative determination of analytes without many processing steps as well as specific identification of multiple analytes in biological specimens.

• Tuberculosis and Respiratory Diseases
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• 제45권2호
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• pp.271-279
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• 1998

연구배경: 결핵의 유병률은 감소하는 추세이나 노인, 항암약물요법, HIV 감염 풍에 의해 면역기능이 약화된 환자에 있어서 결핵의 발생이 문제가 되고 있으며, 특히 다제내성균주의 출현은 큰 문제이다. 결핵진단법 중 체액에서 도말검사나 배양검사를 통해서 Myco-bacterium tuberculosis를 검출하는 것이 표준진단법이나, 도말검사는 상대적으로 민감도가 낮고 배양검사는 오랜시간이 소요된다. 중함연쇄반응을 이용하여 결핵균의 DNA를 검출하는 방법은 매우 민감하나 비용이 많이 소요된다. ELISA(enzyme linked immunosorbent assay)를 이용하여 혈청에서 결핵균 특이항원에 대한 항체를 검출하는 방법이 객담도말음성인 활동성 폐결핵환자를 다른 비결핵성 폐질환으로부터 감별하는데 유용한지를 확인하고자 하였다. 방 법: 연세대학교 세브란스 병원에 입원한 183명의 객담도 말음성인 폐질환환자에서 항산균에 대한 객담도말 및 배양검사와 결핵균 특이 항원인 recombinant 38 kilo-dalton 항원과 culture filtrate항원을 이용한 ELISA 검사를 시행하였다. 결 과: 35명의 활동성 폐결핵환자 중 18명에서 배양검사상 Mycobacterium tuberculosis를 검출할 수 있었다. 38 kDa와 culture filtrate에 대한 흡광도는 활동성 폐결핵환자들에서 비결핵성 폐질환자들보다 유의하게 높았다 (p<0.05). 활동성 폐결핵환자 중 객담배양양성과 음성군사이에 38 kDa와 culture filtrate에 대한 홉광도의 유의한 차이는 없었다 (p>0.05) 객담도말음성인 환자에 있어서 38 kDa과 culture filtrate의 민감도는 각각 20.0%와 31.4%였고 특이도는 각각 95.3%와 93.9%였다. 결 론: 객답도말검사 음성인 활동성 폐결핵환자에 있어서 ELISA를 이용한 38 kDa과 culture filtrate 항원에 대한 혈청항체검사법은 기존진단방법보다 낮은 민감도를 보여, 비결핵성 폐질환으로부터 활동성 폐결핵을 감별진단하는데 크게 도움이 되지 않을 것으로 여겨진다.