• Journal of Food Hygiene and Safety
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• v.31 no.1
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• pp.28-35
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• 2016

Species identification of animal tissues in meat products is an important issue to protect the consumer from illegal and/or undesirable adulteration; for economic, religious and health reasons. In this reason, accurate analytical methods are needed for the labeling of meat products with requiring simple and fast procedure. Recently, applications of PCR in food analysis have been increased because of their simplicity, specificity and sensitivity. Therefore, in this study, a multiplex PCR assay was developed for the simultaneous identification of eight species of cow, pig, chicken, duck, goat, sheep, horse and turkey from raw meats. The primers were designed in different regions of mitochondrial 16S RNA after alignment of the available sequences in the GenBank database. Two multiplex primer sets were designed as Set 1 (cow, pig, chicken, duck) and Set 2 (goat, sheep, horse, turkey), respectively. Total 274 samples from cow (n = 55), pig (n = 30), chicken (n=30), and duck (n = 30), goat (n = 40), sheep (n = 33), horse (n = 41), and turkey (n = 15) were tested. The primers generated specific fragments of 94, 192, 279, 477 bp (pig, chicken, cow, duck), 670, 271, 152, 469 bp (goat, sheep, horse, turkey) lengths for eight species, respectively. The animal species specificity was 100% in all eight samples in the multiplex PCR assay. The detection limit of the multiplex PCR assay showed from 100 fg to 1 pg of template DNA from extracted from raw meats. When applying multiplex PCR assays to sample from pork/beef and pork/chicken, beef/chicken tested raw mixed meats and heat-treated ($83^{\circ}C$ for 30min, $100^{\circ}C$ for 20min, and $121^{\circ}C$ for 10min) mixtures, detection limit was 0.1% level beef, pork and pork in beef and chicken in pork and 1.0% level pork in chicken. This study suggest that the developed multiplex PCR assay can be used for rapid and simultaneous species identification of cow, pig, chicken, duck, goat, sheep, horse and turkey from meats.

• The Korean Journal of Nuclear Medicine
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• v.32 no.4
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• pp.344-353
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• 1998

Purpose: The purpose of this study was to evaluate the diagnostic accuracy of Tc-99m labeled antigranulocyte antibody immunoscintigrapy in the diagnosis of osteomyelitis and compare with the results of triphasic bone scan. Materials and Methods: The study population was 39 patients (22 male, 17 female) who had uncertain diagnoses of osteomyelitis. Fifteen patients had history of orthopedic surgery, and 5 had previous fracture. One milligram of monoclonal antibody against NCA-95 was labeled with 370 MBq of Tc-99m, injected intravenously, and 4 hour images were obtained. Triphasic bone scan images were obtained in 30 patients. The final diagnosis was confirmed by bacteriologic culture, biopsy or long term clinical follow up. Results: Twenty one patients were confirmed to have osteomyelitis (1 acute, 20 chronic). Eighteen patients were without osteomyelitis. Antigranulocyte antibody immunoscintigraphy had a sensitivity of 71% (15/21), and a specificity of 89% (16/18), while the sensitivity and specificity of triphasic bone scan was 93% (13/14) and 38% (6/16), respectively. Antigranulocyte antibody scan showed higher specificity of 100% (11/11) in comparison with 33% (3/9) of triphasic bone scan in patients with history of orthopedic surgery or fracture. Conclusion: Antigranulocyte antibody immunoscintigraphy is more specific than that of triphasic bone scan and may be helpful in patients with history of surgery or fracture. However, sensitivity is lower than triphasic bone scan in the detection of chronic osteomyelitis.

• Korean Journal of Food Science and Technology
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• v.42 no.1
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• pp.27-32
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• 2010

This study was conducted to monitor aflatoxins in various medicinal herbs, providing available data for the safety of those products. To monitor aflatoxins in medicinal herbs, a total of 400 samples of 40 different herbs were collected in commercial retailers in Seoul, Daejeon, Gwangju, Daegu, and Busan from March to August, 2008. The samples that passed the sensory evaluation were tested for aflatoxins. Aflatoxins in samples were analyzed by HPLC-florescence coupled with photochemical enhancement. Samples were extracted with 70% methanol and then diluted to the appropriate concentration. A refining process was performed using an immunoaffinity column. The analytical method used in this study was validated. The $R^2$ value for aflatoxin $B_1$ was 0.99946, and the detection range was from 0.25 to 10.0 ng/mL. The accuracy of the analysis was ranged from 83.2% to 101.8%. The relative standard deviation (RSD) in the aflatoxin $B_1$ analysis was 3.4%, demonstrating the precision of this method. In addition, the detection limit and quantitative analysis limit of aflatoxin $B_1$ was $0.53\;{\mu}g/kg$ and $1.76\;{\mu}g/kg$, respectively. These results indicated that the analytical method used in this study was appropriate. The results of HPLC showed that 1% (4 samples) of the samples may contain aflatoxins. The concentration of quantified aflatoxin was $2.3\;{\mu}g/kg$ for both Quisqualis fructus and Remotiflori radix samples. The other samples were below the limit of quantification. Moreover, the concentration of aflatoxin $B_1$ which is made by specific fungi were below the level of regulation. Only 20% of aflatoxin $B_1$ were transferred to hot water. Therefore, the levels of aflatoxins in medicinal herbs were considered to be safe especially considering the aflatoxin transfer ratio.

• Tuberculosis and Respiratory Diseases
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• v.49 no.5
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• pp.558-567
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• 2000

Background : Recently, serologic techniques for tuberculosis have been developed and some of them, which are focusing on detection of serum antibodies mainly directed against specific 38-kDa Mycobacterium tuberculosis, have already been introduced into the markel. In this study, diagnostic significance of a new serologic test(ELISA kit) for pulmonary tuberculosis was evaluated. Method : Serologic test with newly developed ELISA kit was performed upon 474 individuals, who include 333 active pulmonary tuberculosis patients, 80 healthy cases, and 61 tuberculosis contact cases. This serologic test was based on the ELISA technique and designed to detect antibodies to mixed complex antigens including 38-kDa, which were developed by Erume Biotech Co., Seoul. Active pulmonary tuberculosis was diagnosed by sputum AFB smear and culture methods. Results : The seropositivities using this ELISA kit were 82.1% and 73.6% in smear-positive and negative groups among active pulmonary tuberculosis, respectively. And, it also showed that seronegativities were 97.5% and 85.2% in healthy and contact groups, respectively. As a whole, the results of our study using the ELISA kit as a diagnostic method for pulmonary tuberculosis showed 80.0% sensitivity for active pulmonary tuberculosis, 97.5% specificity, 96.1% positive predictive value, and 65.0% negative predictive value when the prevalence of tuberuclosis in the samples was 60.1%. Conclusion : Our results reveal that the detection of antibody its reaction with 38-kDa antigen of M. tuberculosis is not sufficient to be accepted as single diagnostic method for pulmonary tuberculosis. However, they suggest that ELISA kit may be considered as an adjunctive test to standard diagnostic techniques of pulmonary tuberculosis.

• KIPS Transactions on Computer and Communication Systems
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• v.7 no.6
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• pp.155-164
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• 2018

Many malicious programs have been compressed or encrypted using various commercial packers to prevent reverse engineering, So malicious code analysts must decompress or decrypt them first. The OEP (Original Entry Point) is the address of the first instruction executed after returning the encrypted or compressed executable file back to the original binary state. Several unpackers, including PinDemonium, execute the packed file and keep tracks of the addresses until the OEP appears and find the OEP among the addresses. However, instead of finding exact one OEP, unpackers provide a relatively large set of OEP candidates and sometimes OEP is missing among candidates. In other words, existing unpackers have difficulty in finding the correct OEP. We have developed new tool which provides fewer OEP candidate sets by adding two methods based on the property of the OEP. In this paper, we propose two methods to provide fewer OEP candidate sets by using the property that the function call sequence and parameters are same between packed program and original program. First way is based on a function call. Programs written in the C/C++ language are compiled to translate languages into binary code. Compiler-specific system functions are added to the compiled program. After examining these functions, we have added a method that we suggest to PinDemonium to detect the unpacking work by matching the patterns of system functions that are called in packed programs and unpacked programs. Second way is based on parameters. The parameters include not only the user-entered inputs, but also the system inputs. We have added a method that we suggest to PinDemonium to find the OEP using the system parameters of a particular function in stack memory. OEP detection experiments were performed on sample programs packed by 16 commercial packers. We can reduce the OEP candidate by more than 40% on average compared to PinDemonium except 2 commercial packers which are can not be executed due to the anti-debugging technique.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.22 no.1
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• pp.31-44
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• 2017

Pfiesteria piscicida is one of heterotrophic dinoflagellate having toxic metaboliges, and it is difficult to detect and quantify this dinoflagellate via light microscope due to small size and morphological similarity with Pfiesteria-like dinoflagellate (PLD) species. Alternatively, we developed quantitative real-time PCR assay based on EvaGreen and determined field accessibility throughout the investigation of distribution in the entire Korean coastal waters and population dynamics in Shihwa Lake. The P. piscicida-specific primers based on internal transcribed spacer 1 (ITS 1) were designed and the specificity of primers was confirmed by PCR with other genomic DNAs which have genetic similarity with target species. Through real-time PCR assay, a standard curve which had a significant linear correlation between log cell number and $C_T$ value ($r^2{\geq}0.999$) and one informative melting peak ($88^{\circ}C$) were obtained. These results implies that developed real-time PCR can accurately detect and quantify P. piscicida. Throughout the field applications of real-time PCR assay, P. piscicida was distributed in western (Mokpo and Kimje) and easthern (Gangneng) Korean coastal water even though light microscopy failed to identify P. piscicida. In the investigation of population dynamics in Shihwa Lake, the density of P. piscicida was peaked in June, July and August 2007 at St. 1 where salinity (${\leq}15psu$) was lower than the other 2 sites. In this study, we successed to develop EvaGreen bassed real-time PCR for detection and quantification of P. piscicida in fields, so this developed assay will be useful for various ecological studies in the future.

• Laboratory Medicine Online
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• v.1 no.2
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• pp.100-104
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• 2011

Background: Malaria is a problematic disease in Korea, and microscopic examination of Giemsa-stained blood smear has been used as the gold standard for its diagnosis. However, this technique is time-consuming and has low sensitivity in samples with low numbers of malarial parasites (<20 parasites/μL). Here, we evaluated the performance characteristics of the LG Advansure^TM Malaria P.f./P.v. real-time QPCR (LG life sciences, Korea). Methods: Blood samples from 173 persons who visited Korea University Ansan Hospital were evaluated. QPCR was performed in 73 malaria patients and 100 healthy subjects by using the LG Advansure Malaria P.f./P.v. real-time QPCR^R kit, and the results were compared with those of microscopy. The detection limit of this kit was determined by serial dilution of Plasmodium-infected blood with normal blood (blood not infected with Plasmodium). Results: Among the 73 patients that were microscopically confirmed to have malaria (Plasmodium vivax infection, N=70, P. falciparum infection, N=3), 69 patients were diagnosed with P. vivax infection and 3 were diagnosed with P. falciparum infection by LG Advansure^TM Malaria P.f./P.v. realtime QPCR. Both the tests indicated absence of infection in the 100 healthy subjects. The detection limit of LG Advansure^TM Malaria P.f./P.v. real-time QPCR was 0.1 parasite/μL. Conclusions: LG Advansure^TM Malaria P.f./P.v. real-time QPCRis a very sensitive and specific technique and can be used as a confirmatory test for malaria.

• Journal of Life Science
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• v.22 no.4
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• pp.524-531
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• 2012

Soybean is one of the most common food materials causing food hypersensitivity reactions in Korea. In this study, we have investigated the effect of roasting and fermentation on the allergenicity of soybean. Three kinds of soybean ($Daepung$, $Daewon$, and $Taegwang$) were prepared as raw, roasted, and fermented by $Bacillus$ $subtilis$ GSK 3580, and then their proteins were extracted. The proteins were separated using SDS-PAGE, and the detection of IgE specific to soybean proteins was performed by immunoblotting using 7 sera of soybean allergy patients and non-allergic control individuals. Serum specific IgE to soybean was measured by ELISA. The SDS-PAGE of raw soybean proteins showed various-sized bands ranging from 9 to 76 kDa, which are known as major allergens. In particular, 9, 21, 34, 52, 72, and 76 kDa proteins are known as LTP, Kunits trypsin inhibitor, $Gly$ m Bd 30K, ${\beta}$-subunit, ${\alpha}$-subunit, and ${\alpha}$'-subunit of ${\beta}$-conglycinin, respectively; these are major allergens in soybean. In contrast, only peptides of less than 35 kDa were found in roasted and fermented soybeans. IgE immunoblot analysis of three roasted species of soybeans commonly detected at 38-40 kDa and 10-15 kDa. The protein bands in fermented soybean showed very weak signals or were not detected. In addition, the reactivity of most patients' sera to soybean was decreased after roasting and fermentation. With these results, it may be concluded that the allergenicity of soybeans is reduced by the roasting and fermentation processes. It is supposed that allergenic proteins in soybean were degraded by heat treatment methods and proteolytic enzymes were secreted from fermenting microorganisms.

• Tuberculosis and Respiratory Diseases
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• v.53 no.1
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• pp.17-26
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• 2002

Background : The detection and early elimination of the causes for acute respiratory distress syndrome(ARDS) at the initial stage can result in a more favorable prognosis. Miliary tuberculosis as a cause of the ARDS is quite rare. A diagnosis of miliary tuberculosis is difficult due to the diversity of radiological patterns and non-specific clinical finfings, and low sensitivity of sputum examinations for acid-fast bacilli(AFBs). An analysis of the clinical data is the first step in diagnosing these unusual, rare cases. Materials and Methods : In this study the clinical features, laboratory data, radiological findings and diagnostic methods were analyzed in 9 cases with an initial presentation of ARDS due to miliary tuberculosis. The ARDS was defined by the definition of the American-Europian consensus conference 1992. Results : The mean age of the patients was $67{\pm}18$ years (F:M=7:2). The chief complaints were dyspnea(5/9), coughing (3/9) and fever(5/9). On a physical examination, fine or coarse crackles were noted(6/9). The ARDS developed on average 6.7 days after the initial respiratory symptoms. The mean $PaO_2/FiO_2$ of the patients was $133.5{\pm}53.4$, the number of cases with a WBC<5000/$mm^3$ was 4 out of 9 cases. A platelet count<70,000/$mm^3$ was observed in 2 out of 9 cases, and the serum albumin level was $2.6{\pm}0.6$ g/dL. The initial simple chest PA showed ground glass appearances and consolidation in all cases, However, the miliary nodular densities were observed in only 4 out of the 9 cases. HRCT revealed alveolar densities and a consolidation in 5 out of 6 cases, and miliary nodules in 5 out of 6 cases, The diagnosis of tuberculosis was made by a liver biopsy (4/4, 100% sensitivity), a bone marrow biopsy (1/2, 50% sensitivity), and an open lung biopsy (1/1), the sputum AFB was positive in only 2 out of 9 cases. The patient was treated with INH, RFP, EMB, PZA, and steroids. The survival rate was 55.5%. Conclusion : Miliary tuberculosis should be considered as one of the causes for ARDS in areas where there is a high prevalence of tuberculosis. The chief complaints of the patients on admission are dyspnea, fever and coughing without any specific riskfactors. A liver biopsy is particularly useful in ARDS patients with mechanical ventilation to determine the causes of the ARDS if miliary tuberculosis is suspected as being the underlying disease.

• Clinical and Experimental Pediatrics
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• v.49 no.4
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• pp.439-445
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• 2006

Purpose : ${\alpha}$-Galactosylceramide (${\alpha}$-GalCer)-stimulated human $V{\alpha}24$ natural killer T (NKT) cells exert antitumor activity against some leukemia in a CD1d dependent and TCR-mediated manner, but could not kill CD1d - negative neuroblastoma (NB) cells. There are few reports about the direct antitumor effect of highly secreted cytokines by these cells on activation. In this study, using a cell-free supernatant (SPN) collected from plate bound hCD1d/${\alpha}$ GalCer tetramers-stimulated NKT cells, we examined whether they could be helpful in the immunotherapeutic treatment of NB. Methods : Cells were cultured in IMDM. The cytokines produced by NKT cells were measured with Cytometric Bead Array (CBA) analysis. Cell viability was evaluated by calcein-AM fluorescence with digital image microscopy scanning (DIMSCAN). The percentage of specific apoptosis was calculated by flow cytometric detection of apoptosis using annexin V and 7-AAD. Results : The activated NKT cells secreted high levels of IL-2, INF-${\gamma}$, TNF-${\alpha}$. The SPN was significantly cytotoxic against four out of eight tested NB cell lines, through mainly apoptosis as evidenced by annexin-V staining and inhibition with the pretreatment of pancaspase blocker. This apoptosis was significantly inhibited when anti-TNF-${\alpha}$ and anti-IFN-${\gamma}$ neutralizing mAbs were used separately and it was completely abolished when the two mAbs were combined. Conclusion : IFN-${\gamma}$ and TNF-${\alpha}$ produced by NKT cells could exert synergistically direct antitumor activity through apoptosis on some NB cell lines.