• Korean Journal of Environmental Agriculture
• /
• v.12 no.3
• /
• pp.298-308
• /
• 1993

Immunochemical assay, ELISA for small molecules such as pesticides are rapid, sensitive, cost effective and can easily analyze with large samples. ELISA is one of several powerful biotechnologies immediately applicable to pesticide analysis. This review lists the advantages and disadvantages of the ELISA and elucidate the steps in assay development using examples from this laboratory. The focus is primarily on hapten synthesis strategies, protein conjugation, Immunization, assay format, and assay validation.

• Proceedings of the PSK Conference
• /
• 2003.04a
• /
• pp.258.1-258.1
• /
• 2003

The Dystaenia takeshimana (Nak.) Kitagawa is distributed in Ulreung island and it is an endemic species in korea. The MeOH extract from the root of D. takeshimana (Nak.) Kitagawa shows a good activity in anti-inflammatory assay (sPLA2IIA inhibition assay, COX-2 inhibition assay, 5-LO inhibition assay). (omitted)

• Annals of Clinical Microbiology
• /
• v.21 no.4
• /
• pp.86-91
• /
• 2018

Background: The PANA RealTyper HPV kit (PANAGENE, Korea; PANA RealTyper) was developed to genotype human papillomavirus (HPV) and was based on multiplex real-time PCR amplification and melting curve analysis. In this study, we compared PANA RealTyper to the AdvanSure HPV GenoBlot assay (LG Life Sciences, Korea; AdvanSure assay) and attempted to evaluate the performance of PANA RealTyper. Methods: A total of 60 cervical specimens were collected from women undergoing routine cervical cancer screening. The AdvanSure assay and PANA RealTyper kit identified the same 20 high-risk genotypes. However, the AdvanSure assay identified 15 low-risk genotypes, while the PANA RealTyper kit identified only 2 but detected 18 low-risk genotypes. Results: Among the total 60 specimens, 54 high-risk genotypes (40 specimens) and 20 low-risk genotypes (18 specimens) were detected. The agreement rates of the assays ranged from 94.4 to 100% for high-risk genotypes. Among 9 genotypes that were positive in the PANA RealTyper kit but negative in the AdvanSure assay, 7 were confirmed as true positive (HPV genotypes 16 (n=1), 39 (n=1), 52 (n=1), 58 (n=2), 68 (n=2)). Among 4 genotypes that were negative in the PANA RealTyper kit but positive in the AdvanSure assay, 3 were confirmed as HPV genotype 59. Among the 19 low-risk genotypes positive in the AdvanSure assay, there were 2 cases of HPV 6 and 1 case of HPV 11. In comparison, only 1 positive case of HPV 6 was determined by the PANA RealTyper kit. Conclusion: The PANA RealTyper kit was comparable with the AdvanSure assay. The PANA RealTyper kit would be useful and suitable for HPV genotyping in the clinical laboratory.

• Journal of the Korean Society of Tobacco Science
• /
• v.26 no.2 s.52
• /
• pp.152-158
• /
• 2004

Among short-term in vitro genotoxicity assays, micronucleus assays are rapid, inexpensive, and less labor-intensive system. We have undertaken a comparative study of sensitivity of cigarette smoke condensate(CSC) by general micronucleus(MN) assay and cytokinesis-block micronucleus(CBMN) assay. In this study, V79 Chinese hamster cells were employed to evaluate and compare the genotoxicity of CSC of Kentucky Reference Cigarette 2R4F by 2 kinds of in vitro MN assay methods. To determine the optimum concentration of cytochalasin B(CYB) to obtain the maximal number of binucleated cells for CBMN assay, triplicate cultures of growing cells were treated with CYB for 15 h. CYB treatments caused a concentration-dependent increase in cytotoxicity($1\~4{\mu}g/mL$) and proportion($0.25\~1\;{\mu}g/mL$) of binucleated cells. These data suggested that 1 ug/mL of CYB is as an optimum dose for CBMN assay in binucleated V79 cells. Short treatment(4 h) of CSC induced a micronucleated cells with a concentration-dependent response in the presence or absence of CYB, but CSC-induced MNs were weakened when S9 was present. Long treatments(19 h) of CSC also induced a significant increase MN formation with a concentration-dependent response. At a concentration of 75 ${mu}g/mL$, the MN cell frequencies of general MN assay and CBMN assay were $6.5\%\;and\;11.7\%$, respectively. Linear regression analysis revealed a good correlation in CBMN assay between a concentration of CSC and MN cell frequency. All these data indicated that CBMN assay is more sensitive to the induction CSC-induced MN than general MN assay.

• Development and Reproduction
• /
• v.5 no.1
• /
• pp.59-71
• /
• 2001

Since the first radioimmunoassay (RIA) was developed in 1970s, many conventional RIAs and non-isotopic immunoassays (NIA) had been developed in which the degree of precision, accuracy, specificity and practicability have progressively increased. Recently ultrasensitive assay method at femtogram to determine testosterone in serum, saliva and feces is required for the study of sexual dysfunctions in male and female, monitoring the psychological stress and conditions, aging process such as menopause and partial androgen deficiency in aging male, the hormonal changes of small experimental animals etc. This review discussed the recentd evelopments of steroid assay methods, based upon the testosterone assay results of authors far 20 years, and the problems associated the assay set-up, the characterizations and applications of the established procedures, and desifls of assay, reliablity criteria, and the practical aspects of assay set-up and application, based upon the data of the authors. The present study demonstrates the general problems methods to be consider in order to set up the highly sensitive assay methods and to increase the assay quality and the necessity of assay quality control program. To improve the assay quality of each laboratory and to compare the assay results in homeland, the national QC programs should be organized.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.37 no.4
• /
• pp.472-476
• /
• 2008

The possibility of DNA comet assay as a rapid method for screening the irradiated vegetables and grains was evaluated. Vegetables (spring onion, garlic, and tomato) irradiated at $0{\sim}3$ kGy and grains (rice flour and black soybean) irradiated at $0{\sim}9$ kGy were used as samples. Optimum DNA comet assay conditions, such as elution, sedimentation of suspension, and lysis time of cell, were established. The optimum conditions for vegetables were 10 min for the elution time, 0 min for the sedimentation time, and 5 min for the lysis time. The optimum conditions for grains were 15 min for the elution time, 60 min for the sedimentation time, and 30 min for the lysis time. For the food application of DNA comet assay, it was possible to screen various food samples irradiated at the following doses: spring onion at 2 kGy, garlic at 3 kGy, tomato at 1 kGy, rice flour at 9 kGy, and black soybean at 3 kGy. Each sample showed different forms and sizes in DNA comet. Therefore, further studies on various methods using comet shape, concentration, or area in DNA comet assay are necessary.

• Korean Journal of Veterinary Service
• /
• v.45 no.1
• /
• pp.1-11
• /
• 2022

A novel porcine circovirus 4 (PCV4) was recently identified in Chinese and Korean pig herds. Although several conventional polymerase chain reaction (cPCR) and real-time PCR (qPCR) assays were used for PCV4 detection, more sensitive and reliable qPCR assay is needed that can simultaneously detect PCV4 and internal positive control (IPC) to avoid false-negative results. In the present study, a duplex qPCR (dqPCR) assay was developed using primers/probe sets targeting the PCV4 Cap gene and pig (glyceraldehyde-3-phosphate dehydrogenase) GAPDH gene as an IPC. The developed dqPCR assay was specifically detected PCV4 but not other PCVs and porcine pathogens, indicating that the newly designed primers/probe set is specific to the PCV4 Cap gene. Furthermore, GAPDH was stably amplified by the dqPCR in all tested viral and clinical samples containing pig cellular materials, indicating the high reliability of the dqPCR assay. The limit of detection of the assay 5 copies of the target PCV4 genes, but the sensitivity of the assay was higher than that of the previously described assays. The assay demonstrated high repeatability and reproducibility, with coefficients of intra-assay and inter-assay variation of less than 1.0%. Clinical evaluation using 102 diseased pig samples from 18 pig farms showed that PCV4 circulated in the Korean pig population. The detection rate of PCV4 obtained using the newly developed dqPCR was 26.5% (27/102), which was higher than that obtained using the previously described cPCR and TaqMan probe-based qPCR and similar to that obtained using the previously described SYBR Green-based qPCR. The dqPCR assay with IPC is highly specific, sensitive, and reliable for detecting PCV4 from clinical samples, and it will be useful for etiological diagnosis, epidemiological study, and control of the PCV4 infections.

• Parasites, Hosts and Diseases
• /
• v.54 no.1
• /
• pp.1-8
• /
• 2016

Laboratory workers, in resource-poor countries, still consider PCR detection of Giardia lamblia more costly and more time-consuming than the classical parasitological techniques. Based on 2 published primers, an in-house one-round touchdown PCR-RFLP assay was developed. The assay was validated with an internal amplification control included in reactions. Performance of the assay was assessed with DNA samples of various purities, 91 control fecal samples with various parasite load, and 472 samples of unknown results. Two cysts per reaction were enough for PCR detection by the assay with exhibited specificity (Sp) and sensitivity (Se) of 100% and 93%, respectively. Taking a published small subunit rRNA reference PCR test results (6%; 29/472) as a nominated gold standard, G. lamblia was identified in 5.9% (28/472), 5.2%, (25/472), and 3.6% (17/472) by PCR assay, $RIDA^{(R)}$ Quick Giardia antigen detection test (R-Biopharm, Darmstadt, Germany), and iodine-stained smear microscopy, respectively. The percent agreements (kappa values) of 99.7% (0.745), 98.9% (0.900), and 97.7% (0.981) were exhibited between the assay results and that of the reference PCR, immunoassay, and microscopy, respectively. Restriction digestion of the 28 Giardia-positive samples revealed genotype A pattern in 12 and genotype B profile in 16 samples. The PCR assay with the described format and exhibited performance has a great potential to be adopted in basic clinical laboratories as a detection tool for G. lamblia especially in asymptomatic infections. This potential is increased more in particular situations where identification of the parasite genotype represents a major requirement as in epidemiological studies and infection outbreaks.

• Toxicological Research
• /
• v.14 no.3
• /
• pp.427-433
• /
• 1998

The acute and genetic toxicity of DK1002 was subjected in this study. DK1002 which is a morphine-like new drug candidate synthesized by Dong-Kook Pharmaceutical Co. Ltd. is now under developing as a analgesics that have better drug efficacy and least addictive property. In acute toxicity study, the 50% lethal doses ($LD_{50}$) of DK1002 were determined as>2000mg/kg (p.o.), 237.0mg/kg(i.p.), 57.5mg/kg(i.v.), and 1266.9mg/kg (s.c.). And also, to study the genotoxicity of DK1002, we performed bacterial reversion assay with Salmonella typhimurium TA98, TA100, TA1535, and TA1537, and in vitro chromosomal aberration assay with Chinese hamster lung cells in the presence and absence of S-9 metabolic activation system. In vivo micronucleus assay using mouse bone marrow cells was also performed. From these results, DK1002 was revealed nonmutagenic potential in S. typhimurium TA98, TA100, TA1535, and TA537 both in the absence and presecne of metablic activation system. No clastogenicity of DK1002 was observed in chromosomal aberration assay in vitro as well as in micronucleus assay in vivo.

• Korean Journal of Food Science and Technology
• /
• v.30 no.2
• /
• pp.450-455
• /
• 1998

Pine has been known as a traditional medicinal plant and as showing a physically beneficial function to a human being. Therefore, this study was performed to investigate the physiological activities of main pine neddles. Ethanol extracts from pinus needles did net exhibit any mutagenicity. On the contrary, inhibitory effects of ethanol extract were observed on mutagenicity induced by N-methyl-N'-nitro-N-nitrosoguanidine(MNNG), 4-nitroquinoline-1-oxide (4NQO), 3-amino-1,4-dimethyl-5H-pyrido-(4,3-b)indol (Trp-P-1) and benzo(a)pyrene $(B({\alpha})P)$ using Salmonella typhimurium reversion assay. On direct-acting mutagen (MNNG, 4NQO) and indirect-acting mutagen (Trp-P-1, $(B({\alpha})P)$, we observed higher inhibitory effect. Stepwise fractionation of the ethanol extract was done by using ether, chloroform, ethyl acetate, butanol and water to obtain effective fraction. Among them, water fractions $(100\;{\mu}g/plate)$ of Pinus thunbergii, Pinus rigida, Pinus densiflora and Pinus koraiensis showed high inhibition of 91.65%, 94.7%, 84.22% and 79.02%, respectively, on the mutagenicity of MNNG in Salmonella typhimurium TA100.