• The Korean Journal of Physiology
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• v.23 no.1
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• pp.89-98
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• 1989

In order to produce antibody for use in radioimmunoassay of gastrin in physiological concentration, four rabbits of New Zealand white were immunized with synthetic human gastrin-17-I conjugated to hemocyanin with EDC. Among them, only one rabbit produced antibody that could bind 50% of $^{125}I-gastrin$ at a final dilution of 1:25,000. $^{125}I-gastrin$ was prepared with synthetic human gastrin-17-I and $NaI^{125}$ by lactoperoxidase technique. The product was then purified on a column of Sephadex Gl5/G5O (7:3, w/w) followed by a column of DEAE sephadex A-25. The specific radioactivity of the purified $^{125}I-gastrin$ was in the range of 347-1429 ${\mu}Ci/nmole$ when determined by the self-displacement method. The effective affinity constant $(K_{eff})$, total binding sites (N), heterogeneity index $({\alpha})$ and average affinity constant $(K_{0})$ of the anti-gastrin serum calculated from Scatchard plot as well as Sips plot were $1.77{\times}10^{11}/M$, 255 nM, 0.84 and $0.79{\times}10^{11}/M$, respectively. When radioimmunoassay was performed with the anti-gastrin serum, it was confirmed that the mean concentration of gastrin immunoreactivity in plasma was increased by feeding in humans and rats, and also increased by bombesin administration in rats. The results indicate that the anti-gastrin serum produced in the present investigation is suitable for radioimmunological determination of gastrin in physiological concentration.

• The Korean Journal of Financial Management
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• v.21 no.1
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• pp.205-229
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• 2004

The deviation from put-call parity condition may affect market prices since it provides an opportunity of arbitrage to many participants. This study uses the KOSPI200 index data and examines the interdependence among spot, futures, and options contracts by examining whether the deviations from the parity have significant roles in price formation. Whenever the parity condition is violated, the deviation tends to affect the prices significantly in most markets. The results show that positive values of deviation are associated with the fall of the prices in the spot and put option contracts and the rise of the call option premiums, thus decreasing the deviations. Also, the decreasing impact of deviations lasts for at Beast an hour in most markets. Futures prices, however, do not show clear relations with the deviations, which suggests the possibility that futures markets lead other markets.

• The Journal of Engineering Geology
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• v.25 no.3
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• pp.349-356
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• 2015

Although geophysical methods are useful and generally provide valuable information about the subsurface, it is important to recognize their limitations. A common limitation is the lack of sufficient contrast in physical properties between different layers. Thus, multiple methods are commonly used to best constrain the physical properties of different layers and interpret each section individually. Ground penetrating radar (GPR) and shallow seismic reflection (SSR) methods, used for shallow and very shallow subsurface imaging, respond to dielectric and velocity contrasts between layers, respectively. In this study, we merged GPR and SSR data from a test site within the Cheongui granitic mass, where the water table is ~3 m deep all year. We interpreted the data in combination with field observations and existing data from drill cores and well logs. GPR and SSR reflections from the tops of the sand layer, water table, and weathered and soft rocks are successfully mapped in a single section, and they correlate well with electrical resistivity data and SPS (suspension PS) well-logging profiles. In addition, subsurface interfaces in the integrated section correlate well with S-wave velocity structures from multi-channel analysis shear wave (MASW) data, a method that was recently developed to enhance lateral resolution on the basis of CMP (common midpoint) cross-correlation (CMPCC) analysis.

• Journal of Life Science
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• v.18 no.3
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• pp.374-380
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• 2008

Rapid detection of enterovirus (EVs) is important in the management of aseptic meningitis. We examined the relative efficiency and specificity of the real-time nucleic acid sequence-based amplification (NASBA) comparing with the established reverse transcription polymerase chain reaction (RT-PCR) and viral culture method which were used for the detection of enterovirus RNA in clinical specimens. Of the total 292 samples, 145 were found to be positive to enterovirus RNA by real-time NASBA, 101 were positive by viral culture, and 86 were positive by RT-PCR. 147 samples and 46 samples were determined to be negative and positive by all methods respectively, but 4 samples were positive only by real-time NASBA. To compare the specificity of each method, various clinical samples which were diagnosed for herpes simplex virus (HSV)-1, HSV-2, adenovirus, mumps, and rhinovirus were applied. Except one rhinovirus sample which was false positive to enterovirus RNA by RT-PCR, the other different samples were negative to all three methods. The real-time NASBA procedure can be completed within 5 hours in contrast with 9 hours for the RT-PCR and 3-14 days for the viral culture. From this study, it was suggested that the real-time NASBA assay could be a standardized, rapid, specific, and sensitive procedure for the detection of enterovirus RNA.

• Korean Journal of Food Science and Technology
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• v.28 no.6
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• pp.1184-1187
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• 1996

A simple and rapid detection system for $aflatoxin\;M_1\;(AFM_1)$ in cow's milk by an enzyme-linked immunosorbent assay (ELISA) was developed. Specific antibodies against $AFM_1$, conjugated to bovine serum albumin $(AFM_1-BSA)$ were raised in rabbits and purified. The cross-reactivities of the antibodies against aflatoxin analogs were less than 29.9%. When a competitive direct ELISA (cdELISA) for $AFM_1$, established by use of the antibodies was applied to the spike test of $AFM_1$ onto uncontaminated cow's milk, the assay recovery was unstable unless cow's milk was diluted to 40% (2:3) with phosphate buffered saline (PBS). In that condition of sample dilution, the mean ELISA recovery of $AFM_1$, from the cow's milk was 113% (coefficient of variation (CV) of each recovery percentage, 8.2%) in the range of $0.3{\sim}3.0\;ppb$. These results showed that the ELISA system could be a convenient tool to monitor the contamination of AFM1 more than 0.5 ppb in cow's milk (FDA allowance limit) easily.

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.3
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• pp.151-171
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• 2023

This study analyzed farmer's responses to the pilot project in advance of the nationwide expansion of the farm-customized early warning service for weather risk management by conducting a survey among all farmers who received text messages of this service. We analyzed not only the satisfaction of farmers with the early warning service, but also the effectiveness of the service in preventing agrometeorological disasters through cross-tabulation analysis of survey results. More than 330 farmers participated in the survey, and more than 60% of the respondents said that they had prevented or mitigated crop disasters by using the early warning service. The cross-tabulation analysis showed that farmers who perceived the field-specific weather information of the early warning service to be more accurate than the weather forecast were statistically significantly more likely to prevent crop disasters than those who did not. According to our case study, farmers who grew open field fruit crops were particularly sensitive to weather information and confirmed that early warning services, along with disaster prevention facilities, were effective in preparing for freezing and frost injury that had been occurring frequently under the influence of climate change. This study is significant in that it is the first to systematically analyze the effectiveness of the farm-customized early warning service for weather risk management based on extensive surveys. It is expected to contribute to exploring ways to develop the service ahead of the nationwide expansion of the early warning service in the near future.

• Food Science of Animal Resources
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• v.28 no.5
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• pp.651-659
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• 2008

This study aimed to develop polyclonal antibodies to regional inedible adipocytes of Korean native cattle (Hanwoo) and investigate cross-reactivity of the antibodies. Patterns in plasma membrane proteins (PMPs) from abdominal and subcutaneous adipocytes of Hanwoo isolated by collagenase digestion were investigated using SDS-PAGE. As antigens, abdominal and subcutaneous adipocyte PMPs of Hanwoo were injected to sheep 3 times at 3 wk intervals for passive immunization, and non-immunized serum and antisera were collected before and after the injections. Titers of the antisera obtained from sheep and their cross-reactivities with heart, kidney, liver, lung, muscle, and spleen of Hanwoo were determined by ELISA. Isolation and culture of abdominal and subcutaneous adipocytes of Hanwoo were performed for analysing LDH concentration. Based on the SDS-PAGE analysis, specific proteins of PMPs in abdominal and subcutaneous adipocytes appeared despite rather similar patterns between both adipocytes. At the level of 1:1,000 dilution, little antibody reactivity appeared in non-immunized serum whereas the antisera had relatively strong reactivity up to the level of 1:128,000 and 1:64,000 dilution. These findings may indicate that strong antibodies against adipocyte PMPs can be developed using an immunological approach. Extremely low reactivities of abdominal and subcutaneous adipocyte antisera were detected with PMPs of the organs. Both antisera strongly reacted with each adipocyte PMPs and showed statistically (p<0.01) higher cross-reactivities compared with non-immunized serum. In conclusion, these results may indicate that the present polyclonal antibodies against regional inedible adipocyte PMPs are well developed and have safety in cross-reactivities with body organs. Further studies on in vivo cross-reactivity and fat reduction of the antibodies against abdominal and subcutaneous adipocytes PMPs of Hanwoo should be required for inedible fat-reduced high quality beef production.

• Pediatric Infection and Vaccine
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• v.13 no.2
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• pp.89-98
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• 2006

Purpose : The prevalence of serotypes can be changed with respect to age of the patients, regions and times of the surveillance. The aim of this study is to analyze changes in serotype distribution of pneumococcal isolates from Korean pediatric patients. Methods : Four hundred and sixty five strains of S. pneumoniae were isolated from various clinical specimens at the Seoul National University Children's Hospital during a 15 year-period, from 1991 to 2005, were subjected to serotype and penicillin susceptibility. The study period was divided into three 5 year-periods, 1991~1995(period I), 1996~2000(period II), and 2001~2005(period III). Results : Common serotypes were 19F, 23F, 19A, 6B, 14, 6A and 9V in decreasing orders of frequency, and these 7 serotypes accounted for 79% of total 465 strains. In the serotype distribution of invasive infection isolates from children <60 months of age, similar serotypes accounted for 70% of 101 strains. In total strains, the proportion of serotype 19A and 6A increased, while that of serotype 19F and 14 decreased. The majority(75~92%) of vaccine types and cross-reactive types from invasive infection isolates was penicillin-resistant, whereas 34.4% of non-vaccine types was penicillin-resistant. Conclusion : Distribution of serotypes of S. pneuomoniae isolated from Korean children has changed significantly over the last 15 years. The surveillance for pneumococcal serotypes should be continued to monitor changes in serotype distribution which are essential for the establishment of pneumococcal vaccine policy.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.8
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• pp.1344-1350
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• 2003

This study was performed to investigate the antioxidative effect as the inhibition of malondialdehyde (MDA) and bovine serum albumin (BSA) conjugation reaction, inhibition of lipid peroxidation and the scavenging effect on 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical, and antimutagenic capacities as the Ames test in 7 common vegetables taken by Korean for suggestion of prevention and dietetic treatment of chronic diseases and development of antioxidative and antimutagenic functional food. The water fractions of perilla leaves and sedum were most effective in the inhibition of MDA and BSA conjugation reaction showing 62.5% of inhibition rate among 7 vegetables. The inhibition rates of ethanol fractions of sedum and wild water dropwort on the lipid peroxidation were 67.1% and 61.5%, respectively. The ethanol fractions of crown daisy and wild water dropwort showed the most effective results among 7 vegetables in the DPPH radical scavenging capacities showing inhibition rate of 78.8% and 73.6%, respectively. The indirect and direct antimutagenic effects of ethanol extract of 7 vegetables were examined by Ames test using Salmonella typimurium TA98 and TA100. Inhibitory effects of wild water dropwort was superior to the other vegetables on the Ames test. These results suggest that common 7 vegetables taken by Korean are believed to be a possible antioxidative and antimutagenic capacities, although the results were different, more or less, according to the assay method and vegetables used.

• Journal of Life Science
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• v.16 no.6
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• pp.1006-1013
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• 2006

To High Throughput Screening (HTS), a homogeneous fluorescence polarization immunoassay (FPIA) was developed for the quantitative determination of ochratoxin A(OTA) using a $Victor^3$ (PerkinElmer). The homologous tracer, fluorescein-labelled OTA-EDF were synthesized and a specific OTA antibody has been used in the development of the method. It allowed the determination of OTA in the concentration range 0.5-200 ng/ml, with the detection limit of 0.3 ng/ml. The method developed was highly specific and reproducible. OTA spikes in unpolished rice extracts were determinable by FPIA with good recovery. For naturally contaminated unpolished rice samples some disagreement was observed between the results obtained by FPIA and HPLC, which could be related to the a little matrix effect observed for FPIA. Further research is needed to validate the procedure. On the basis of these initial results, this FPIA appears to meet the performance criteria for OTA screening of food samples without a complicated clean-up.