• 한국환경성돌연변이발암원학회지
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• 제24권3호
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• pp.137-142
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• 2004

Dioxin-like compounds are ubiquitous environmental polltants that could be accumulated in biological system and toxic to human and wildlife. Given this issue, it is important to develop a reliable dioxin detection methods for a rational risk assesment of dioxin-like compounds. In this study, we tried to set up and validate a sensitive, reliable risk assessment of dioxin-like compounds. In this study, we tried to set up and validate a sensitive, reliable and rapid bioassay model, CALUX bioassay as a screening tool for routine measurement of dioxin-like conpounds in environmental matrices. For the valisation of CALUX bioassay, firstly, we performed dose-response assay for 2,3,7,8-TCDD, most potent dioxin-like compound, using two different methods CALUX and EROD assay. Induction of luciferase activity and CYPIA catalyzed EROD activity were dose-dependently induced by 2,3,7,8-TCDD, with initial induction at 0.1 pM and maximal induction at 1 nM. In order t determine whether the CALUX bioassay could predict the effects of dioxin-like compounds, 2,3,7,8-TCDD dose-response from CALUX was compared with that from EROD assay. The correlation coefficient ($r^2$) was found to be 0.89, indicating a good correlation between two different methods and the possibility of CALUX bioassay as a useful dioxin detecting method.

• 한국응용곤충학회지
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• 제31권4호
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• pp.452-460
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• 1992

신규 살충성화합물의 개발을 위한 생물검정법 확립의 일환으로 수종의 곤충을 이용하여 침지시간, 약제처리 방법, 공시충의 종간 및 발육태에 따른 살충제의 감수성을 조사하였다. 침지시간, 처리방법, 공시충의 종간 및 발육태에 따라 살충력에 현저한 차이를 보였는데, 침지시간은 엽침지법에서 약 30~60초 침지처리에서 효과가 좋았으며 60초 이상 침지처리에서는 식물체의 내용물이 용출되어 바람직하지 않았다. 처리방법은 콩진딧물과 복숭아혹진딧물 무시암컷, 배추좀나방과 담배거세미나방 3령유충은 엽침지법, 벼멸구 3령약충 또는 성충과 벼유묘 동시분무법, 점박이응애는 엽침지법 또는 분무법이 효과적인 처리방법이었다. 키틴합성저해제의 검정은 벼멸구의 경우 3령약충, 배추좀나방과 담배거세미나방 3령유충, 진딧물류 3령약충 및 점박이응애 유충을 약제가 분무처리된 유묘에 접종하여 검정하는 방법이 적합하였다.

• Communications for Statistical Applications and Methods
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• 제9권2호
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• pp.401-410
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• 2002

This paper revisits parallel-line bioassay problem, from a Bayesian point of view using noninformative priors such as Jeffreys' prior, reference priors, and probability matching priors. After finding the orthogonal transformation, the class of first order and second order probability matching priors are derived. Jeffreys' prior and reference priors are derived also. Numerical examples are given to show the effectiveness of noninformative priors.

• 한국환경독성학회:학술대회논문집
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• 한국환경독성학회 2003년도 추계국제학술대회
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• pp.158-158
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• 2003

Bioassays using gametes of sea urchins are widely used in ecotoxicological assessments of marine environments. Since most of sea urchin species in Korean coastal water spawn from spring to autumn, bioassay with them during the winter is impossible. In the course of developing standard methods for bioassays with Korean species, we found a winter-spawning starfish, Asterias amurensis, Since reproductive mode of asteroids is similar to echinoids, the bioassay protocol for sea urchins could be applied similarly to the starfish. Here, we tested and determined several conditions for the acceptability of bioassay with A. amurensis. The least required time for formation of fertilization membrane of fertilized eggs to be easily distinguished from unfertilized ones was 60 min. The threshold of sperm to egg ratio that could make acceptable fertilization rates in controls was 3000. The allowed time for manipulation of sperm after dilution in seawater was at most 3 hr. The optimal exposure time of sperms when the response against toxicant solution was relatively stable was in the range of 20-60 min. The tolerance range of sperms to the salinity of test solution was 26-38 psu. The sensitivity of A. amurensis sperm was intermediate among marine organisms commonly used in aquatic toxicity tests. The sperm bioassay with A. amurensis can be satisfactorily applied to toxicity assessments of marine environments.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제30권3호
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• pp.186-192
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• 2004

Purpose: Human tooth proteins are highly heterogeneous, comprising diverse proteins derived from a number of genes. The attempts to identify protein for activity of tooth matrix proteins have been defied by several factors. First, the amount of proteins within teeth is very small relative to many extracellular matrix proteins of other tissues. Second, the bioassay system is tedious and needed for long time. Therefore we tried to find easy techniques, which increase the product rate, and an assay of small proteins, with which amino acid sequence is possible without additional procedures. Materials and Methods: Total protein were extracted from 300 g enamel removed teeth and 600 g teeth with 4 mol/L guanidine HCl and purified by gel chromatography. Aliquot of proteins was implanted into muscle pouches in Sprague-Dawley rats for bioassay. By SDS-PAGE and membrane blotting, molecular weight of each protein was estimated and a partial amino acid sequence was obtained. Each fraction blotted on the membrane was cut out and inserted in rat ectopic model. Results: In dissociative method, total tooth proteins were obtained 1mg/ml from enamel removed teeth and 3.5 mg/ml from teeth. In SDS-PAGE, four clear bands at the sites corresponding to 66, 40, 20 and 18 kD. Especially The 66 kD band was clearly exhibited. Amino acid sequencing from tooth could be possible using PVDF membrane blotting technique. In amino acid sequencing, 66 kD protein was identified as albumin. Conclusion: Compared with conventional method for extraction of teeth protein and bioassay of proteins, the methods in this study were easy, time-saving and more productive technique. The matured tooth proteins omitting additional procedure of mechanical removal of enamel were simply analyzed using blotted PVDF membrane. This method seems to make a contribution as a technique for bioassay and amino acid sequencing of protein.

• Biotechnology and Bioprocess Engineering:BBE
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• 제5권6호
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• pp.400-406
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• 2000

Since the 1950s, the numbers of species and chemicals produced have significantly increased. Despite the fact that industrial chemicals have given us numerous benefits, there is no doubt that they have damaged the environment. The chemicals being dispersed on the earth should be carefully controlled to prevent adverse effects. Bioassay is one of the methods to assess chemical safety. In bioassay systems, chemical safety is estimated by monitoring biological responses to environmental pollutants and newly synthesized chemicals. This report introduces multiple-point bioassay systems that are based on chemical sensitivities of microorganisms, responses of one kind of organism, and micro-array technology. Multiple-end-point bioassays enable the prediction of chemicals in the environment and the understanding of toxicities of newly synthesized chemicals.

• 대한임상검사과학회지
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• 제50권4호
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• pp.382-390
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• 2018

임신진단검사는 고대 이집트에서 밀과 보리를 이용한 발아시험으로 시작하였다. 이후 Hippocrates와 Galen을 거쳐 uroscopy를 활용하던 중세를 넘어 1800년대 초반까지도 비과학적 방법들이 사용되었다. 그러나 1800년대 중반 이후 과학적 실험방법과 근거들이 나타나기 시작하면서 임신의 생리학적 특성에 대한 과학적 연구들이 시작되었다. 이와 같은 과학적 연구결과를 활용하려는 최초 시도는1927년 Aschheim와 Zondek의 rat와 mouse를 이용한 bioassay로 시작되었고, 이후 토끼와 개구리를 이용하는 실험으로 발전하였다. 1960년대부터 시작된 면역검사방법은 bioassay의 문제점을 개선하면서 임신진단검사를 일반화하는데 크게 기여하였다. 1976년에는 가정에서 사용할 수 있는 임신진단키트가 출시되어 임신진단을 대중화하는데 기여하였다. 1980년대 이후 진단검사의 기술적 진보는 임신진단검사에도 활용되어 임신진단의 검사신뢰도는 더욱 향상되었으며, 2000년대에는 가정용 임신진단키트의 정확도와 사용편리성이 혁신적으로 향상되었다. 본 조사에서는 임신진단검사의 역사와 과학적 발전과정을 고찰하였다.

• The Korean Journal of Physiology and Pharmacology
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• 제10권6호
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• pp.349-354
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• 2006

The aromatic hydrocarbon receptor (AhR) is a ligand-activated transcription factor that mediates many of the biological and toxicological effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD, dioxin) and related chemicals. The application of recombinant reporter plasmid such as the firefly luciferase gene has proven to be a very effective method to detect these chemicals. The bioassay system, CALUX, is sensitive in directly detecting AhR-agonists from a variety of environmental and biologic materials. However, responses of the AhR-dependent bioassays are dependent on the cell types used. Thus, we developed a sensitive bioassay using the recombinant mouse hepatoma cell (Hepa1c1c7) for the determination of dioxins. The recombinant cell line was stably transfected with firefly luciferase reporter gene (pGudLuc1.1). The transfected cells showed the highest induction of luciferase activity at 4.5 hr and a decrease beyond this time point. The system showed the highest sensitivity of detection ever reported. Upon TCDD exposure cells showed 2 fold increase at 10 pM and 7 fold increase at 100 pM, respectively. The passage number after the transfection played an important role in the sensitivity. The increase of passage number tended to increase the sensitivity of the cells up to 15. The media without phenol red showed a higher induction rate than with phenol red, suggesting the preferable use of phenol red-free media for the bioassay. Since each of the assays has unique characteristics that make them suitable for some screening applications and not others, development of sensitive bioanalytical methods based on a variety of cellular systems in a key to the successful determination of dioxins. The bioassay system developed in this study will contribute to further development of successful screening the AhR agonists among the environmental mixture. In addition, the rapid and sensitive nature of this cellular system can be applied as a valuable tool to screen the dioxin-like moieties among the prodrugs at the initial stage, thereby expediting the new drug discovery.

• Journal of the Korean Statistical Society
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• 제19권1호
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• pp.71-79
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• 1990

In the linear model which consider both the multivariate parallel-line bioassay and the multivariate linear calibration, this paper presents a Bayesian procedure which is an extension of Hunter and Lamboy (1981) and has several advantages compared with the non Bayesian techniques. Based on the methods of this article we discuss the effect of multivariate calibration and give a numerical example.

• Fisheries and Aquatic Sciences
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• 제16권3호
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• pp.159-164
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• 2013

The mouse bioassay and high performance liquid chromatography (HPLC) post-column oxidation method are different methods of quantifying paralytic shellfish poisoning toxins. In this study, we compared their ability to accurately quantify the toxicity levels in two types of field sample (oysters and mussels) with different toxin profiles for routine regulatory monitoring. A total of 72 samples were analyzed by both methods, 44 of which gave negative results, with readings under the limit of detection of the mouse bioassay ($40{\mu}g/100g$ saxitoxin [STX] eq). In 14 oysters, the major toxin components were gonyautoxin (GTX) 1, -2, -3, -4, -5, decarbamoylgonyautoxin-2 (dcGTX2), and decarbamoylsaxitoxin (dcSTX), while 14 mussels tested positive for dcSTX, GTX2, -3, -4, -5, dcGTX2, neosaxitoxin (NEO), STX, and dcSTX. When the results obtained by both methods were compared in two matrices, a better correlation ($r^2=0.9478$) was obtained for mussels than for oysters ($r^2=0.8244$). Additional studies are therefore needed in oysters to investigate the differences in the results obtained by both methods. Importantly, some samples with toxin levels around the legal limit gave inconsistent results using HPLC-based techniques, which could have a strong economic impact due to enforced harvest area closure. It should therefore be determined if all paralytic shellfish poisoning toxins can be quantified accurately by HPLC, and if the uncertainties of the method lead to doubts regarding regulatory limits.