• Korean Journal of Veterinary Research
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• v.38 no.4
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• pp.763-770
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• 1998

Salmonella typhimurium is a causitive agent of diarrhea, fever, gastroenteritis, septicemia and sudden death in piglet. The currently used methods such as IFA, ELISA, DNA hybridization assay is needed a long-time and difficult to detect the organism in carrier animal or contaminated sample with other agents. However, it is important to detect rapidly and sensitively S typhimurium in piglet with other infectious pathogens to minimize an economic loss. Two sets of PCR primer, rfbJ forward primer(5'-AGAATATGTAATTGTCAG-3') and reverse primer(5'-TAACCGTTTCAGTAGTTC-3') were designed to amplify a 882 by fragment of Salmonella serovar type B gene. The target genomic DNA for PCR was extracted from the cultivated materials with various enrichment periods in a nonselective enrichment agar and broth with clinical specimens. The PCR is carried out here made it possible to detect the gene from two hours. Also, the amplified fragment with PCR was cloned into pGEM-T vector and digested with restrict enzyme, and sequenced for the identification of Salmonella serotype B rfbJ gene. Duplicated cultivation agar-broth followed by PCR were performed to develop a rapid and sensitive detection of S typhlmurium based on serovar type. This duplicated cultivation-PCR method provides a sensitive and rapid diagnostic tool to detect Salmonella from infected piglet with improved sensitivity.

• Journal of the Korean Association of Geographic Information Studies
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• v.18 no.4
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• pp.31-42
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• 2015

The objective of this study is to estimate the flood flow of inaccessible regions using satellite-derived rainfall and global geographic data. This study focuses on Dongsingun, an area located upstream of the Cheongcheon River in North Korea. The IFAS model was used to estimate flood flow. The model was calibrated in the Gap Stream watershed in South Korea and verified for the Byeongsung Stream watershed in the Nakdong River basin. Satellite-derived rainfalls for North Korea was revised using ground gauge data. Analysis results using CMORPH and GSMaP_NRT showed $4,886m^3/s$ and $5,718m^3/s$ respectively. In future studies, hydrological analysis in unmeasured and inaccessible regions will be carried out by applying more rainfall events.

• BMB Reports
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• v.37 no.3
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• pp.383-385
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• 2004

RNA interference (RNAi) is a process of sequence-specific gene silencing, which is initiated by double-stranded RNA (dsRNA). RNAi may also serve as an antiviral system in vertebrates. This study describes the inhibition of herpesvirus-6B (HHV-6B) replication by short interference RNAs (siRNAs) that are targeted to the U38 sequence that encodes DNA polymerase. When virus-infected SupT1 cells were treated by siRNA, these cells blocked the cytopathic effect (CPE) and detected the HHV-6B antibody-negative in indirect immunofluorescence assays (IFA). Our result suggests that RNAi can efficiently block Herpesvirus-6B replication.

• Parasites, Hosts and Diseases
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• v.55 no.6
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• pp.623-630
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• 2017

Plasmodium lactate dehydrogenase (pLDH) is a strong target antigen for the determination of infection with Plasmodium species specifically. However, a more effective antibody is needed because of the low sensitivity of the current antibody in many immunological diagnostic assays. In this study, recombinant Plasmodium vivax LDH (PvLDH) was experimentally constructed and expressed as a native antigen to develop an effective P. vivax-specific monoclonal antibody (mAb). Two mAbs (2CF5 and 1G10) were tested using ELISA and immunofluorescence assays (IFA), as both demonstrated reactivity against pLDH antigen. Of the 2 antibodies, 2CF5 was not able to detect P. falciparum, suggesting that it might possess P. vivax-specificity. The detection limit for a pair of 2 mAbs-linked sandwich ELISA was 31.3 ng/ml of the recombinant antigen. The P. vivax-specific performance of mAbs-linked ELISA was confirmed by in vitro-cultured P. falciparum and P. vivax-infected patient blood samples. In conclusion, the 2 new antibodies possessed the potential to detect P. vivax and will be useful in immunoassay.

• Korean Journal of Veterinary Research
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• v.43 no.3
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• pp.463-469
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• 2003

Eight nursery to grower pigs exhibiting weight loss and sudden death were diagnosed as postweaning multisystemic wasting syndrome (PMWS) based on the results of gross findings, histopathology, immunohistochemistry, fluorescent antibody test, virus isolation, PCR, serology, and electron microscopy. Groosly, the pigs had a rough hair coats and were severely emaciated. And moot lymph nodes were pale and enlarged. Lungs were not fully collapsed and exhibited 10 to 40% pale red cranioventral consolidation. Histopathologically, typical lymphohistiocytic interstitial to bronchointerstitial pneumonia, chronic lymphadenitis, severe lymphoid depletion, and basophilic intracytoplasmic inclusions were noted in the most lymphoid tissues. Porcine circovirus panicles were observed in the inguinal lymph node of the pigs by electron microscopy. Porcine circovirus type 2 (PCV2) antigens or viral DNAs were detected in the lesions of all pigs using immunohistochemistry or PCR. Two PCV2 were isolated from a homogenate of pooled lung and lymph node in 2 of the 5 pigs. Additionally, antigens of porcine reproductive and respiratory syndrome virus (PRRSV) and Hemophilus (H.) parasuis were also detected by immunofluorescent antibody test. Serologically, 55% of randomly selected sows and fattening pigs was serum antibody positive to PCV2 by an indirect fluorescent antibody (IFA) test and approximately 18 % of animals in the herd were serologically pooitive by the ELISA kit for PRRSV. To our knowledge, this is the first report of PMWS co-infected with PCV-2, PRRS, and H. parasuis in Korea.

• Korean Journal of Poultry Science
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• v.15 no.3
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• pp.199-206
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• 1988

A total of 3 hybridoma clones producing monoclonal antibody (MCA) against infectious laryngotracheitis virus (ILTV) was established by somatic cell hybridization between mouse myeloma cells and spleen, cells from mice immunized with ILTV. The MCAs were screened by the indirect flourescent antibody (IFA) staining and the specific hybridomas were cloned by limiting dilution method. The MCAs produced by the 3 hybriomas were all classified as immunogloblin G and found to be reacting against common antigen(s) of high and low pathogenic ILTV examined. The titer of these antibodies in mouse ascitic fluid was from $10^5$ to $10^6$. Indirect fluorescent antibody test using these antibodies was found to be quite effective for the detection of ILTV from infected chickens being the most sensitive among the test methods adopted.

• Korean Journal of Poultry Science
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• v.15 no.3
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• pp.207-210
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• 1988

A total of 3 hybridoma clones producting menoclonal antibody (MCA) against Newcastle disease virus(NDV) was raised by cell fusion method. The MCAs did not cross react against other avian or mammalian viruses tested. However, these antibodies reacted with all strains of velogenic and lentogenic NDVs tested indicating that they are unable to discriminate the possible antigenic differences among NDVs. All. the MCAs were classified as IgG type and did not show neutralizing and hemagglutination inhibition (HAI) activity except one clone which has low HAI activity. One of these MCA raised in mouse ascites revealed the titer of $10^6$ by indirect immunofluorescent antibody (IFA) test Using the MCA, virulent NDV could easily be detected from tracheal and conjunctival smears made 2 to 3 days after experimental infection.

• Journal of Advanced Navigation Technology
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• v.12 no.3
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• pp.220-226
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• 2008

This paper proposes the Reconfigurable Doherty Amplifier(RDA) with asymmetric structure which has ${\lambda}/4$ impedance transformer for modulating the load impedance in peaking amplifier path. This structure is possible to implement a compact size for N-stage multi Doherty amplifier and to get almost same characteristics that is compared to conventional Doherty amplifier. To realize the high efficiency amplifier, we were implemented 45 Watts power amplifier at transmitter band of Wideband Code Division Multiple Access(WCDMA) base-station. As a result, in case of WCDMA 1 Frequency Allocation(FA) input signals, this amplifier has obtained a 26.3% Power Added Efficiency(PAE) at 8 dB back-off point from P1dB and an Adjacent Channel Leakage Power(ACLR) is -40.4 dBc at center frequency ${\pm}5MHz$ deviation.

• Parasites, Hosts and Diseases
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• v.34 no.4
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• pp.255-258
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• 1996

Eight 2-day-old SPF Chickens were each inoculated Orally With 3 Sing1e dose Of 5 × 105 oocysts of Cryptosporinium boilevi. and immunoglobulin G (IgG) antibody responses were chronologically measured by indirect immunofluorescent antibody (IFA) assay. Anti-C. bcileyi IgG antibody levels remained high (1 : 106.67 to 1:512.00) for at least 4 months with 330 days of a detectable period. Ten days after the negative conversion, each chicken was re-challenged with 1 × 107 oocysts of the same species. Subsequent infection in 340-day-old individuals caused sudden elevated IgG antibody levels and the titer peaked on day 28 postchallenge inoculation (PCI), at 1:1.024 with a 65 days of detection period. Chickens in primary infection showed oocyst shedding profiles. but did not exhibit any oocyst shedding before or after experimental reinfection.

• Journal of Microbiology and Biotechnology
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• v.12 no.1
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• pp.53-58
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• 2002

To better understand the reservoir host range and distribution of hantaviruses in small mammal populations in Korea, a serological survey was conducted on 1,375 wild rodents and 62 insectivores captured in seven provinces during the six-year period, 1995 to 2000. As determined by the indirect immunofluorescent antibody (IFA) test, 90 ($13.1\%$) of 685 Apodemus agrarius, 47 ($13.6\%$) of 345 Apodemus peninsulae, and 4 ($6.5\%$) of 62 Crocidura laciura were seropositive against the Hantaan virus, while 38 ($13.5\%$) of 282 Eothenomys regulus were seropositive against the Puumala virus. Serological evidence for hantavirus infection was not found in 50 Microtus fortis, six Micromys minutus, six Mus musculus, and one Cricetulus triton. Our serological data indicate that hemorrhagic fever with renal syndrome (HFRS)-related hantaviruses are widely distributed in indigenous rodents in Korea. Particularly noteworthy was the high seropositivity rates among Apodemus peninsulae and Eothenomys regulus captured in certain mountainous regions, suggesting that HFRS may be under-reported among nearby residents or among individuals who might visit such areas for recreational or occupational purposes.