• Proceedings of the PSK Conference
• /
• 2002.04a
• /
• pp.138.3-139
• /
• 2002

• YAKHAK HOEJI
• /
• v.42 no.3
• /
• pp.336-344
• /
• 1998

Effects of ochratoxin A (OTA) on embryo development were studied in cultured whole embryos from 9.5 day gestation rat for 48 h. OTA (more than $0.5{\mu}g/ml$) induced microcephaly in the cultured rat whole embryos. Protein and DNA content, and DNA synthesis were significantly inhibited by OTA. We next examined whether the microcephaly seen in cultured whole embryo partially results from inhibition of differentiation of embryonic midbrain cells. Embryonic midbrain cells were extracted from 12 day gestation rat embryos, and cultured for 96 hr. OTA ibhibited cell differentiation about 50% over control. We also tested whether OTA-induced embryotoxicity would be associated with oxidative damages. We measured the ${\gamma}$-glutamyltranspeptidase (${\gamma}$-GT) and glutathione peroxidase (GPX) activities, and glutathione (GSH) content in both cultured whole embryos and embryonic midbrain cells. OTA decreased GSH content, whereas slightly increased ${\gamma}$-GT activity, but GPX activity was not significantly changed. These results show that OTA caused the microcephaly and its effect may be partially due to the inhibition of cell differentiation of embryonic midbrain cells, but the role of oxidative damages is not clear in embryotoxicity.

• Journal of Environmental Health Sciences
• /
• v.33 no.5
• /
• pp.379-385
• /
• 2007

This study was aimed to investigate the estrogenic activity of Di-(2-ethylhexyl) adipate (DEHA) using immatured type uterotrophic assay. SD rats were treated with DEHA (40, 200, 1000mg/kg/day), estradiol-3-benzoate (EB) $(1{\mu}g/kg/day)$ as positive control on the assay. In immatured-type uterotrophic assay, relative organ weights of kidney and reproductive organs such as ovary at high-dose group were significantly increased compared to those of vehicle control group. DEHA did not influence the levels of serum FSH and LH, and uterine morphological changes such as luminal epithelial height, myometrial thickness and numbers of uterine gland, and BrdU indices. In these results, there was no significant variation by DEHA treatment, suggesting that DEHA appears not to be a endocrine disrupter with estrogenic activity.

• Journal of Food Hygiene and Safety
• /
• v.25 no.3
• /
• pp.278-280
• /
• 2010

This study was aimed to develop a novel qualitative multiplex polymerase chain reaction (PCR) for simultaneous detection of genetically modified (GM) soy and maize within a single reaction. The specific primers designed to detect four respective GM events (A2704-12, MON88017, Bt11, and MON863) were included in the tetraplex PCR system. Each of PCR products for four GM events could be distinguished by agarose gel based on their different lengths. The specificity and reproducibility of this multiplex PCR were evaluated. This multiplex PCR consistently amplified only a fragment corresponding to a specific inserted gene in each of the four GM events and also amplified all four of the PCR products in the simulated GM mixture. These results indicate that this multiplex PCR method could be an effective qualitative detection method for screening GM soy and maize in a single reaction.

• Journal of Pharmaceutical Investigation
• /
• v.30 no.4
• /
• pp.309-318
• /
• 2000

우리나라에서는 1989년 1월 1일 이후 허가된 신약과 동일한 의약품을 제조하거나, 제제개선을 통하여 흡수율을 향상시키는 경우 등에 있어서 생물학적 동등성 시험을 실시하여 두 제제간의 생체이용률을 비교하도록 규정되어 있다. 다른 나라에서도 신약과 동일한 의약품을 허가 받고자 할 경우나 대체조제를 위한 복제의약품의 생산 시 생물학적 동등성 시험자료를 제출하도록 하고 있으며, 이에 따른 생물학적 동등성 시험 기준을 운영하고 있다. 최근 각국에서는 국제적 조화를 이룬 기준을 마련하고자 하는 추세이다. 현재 우리나라에서는 의약분업 실시에 따라 생물학적 동등성 시험의 중요성이 부각되고 있으며 국제적인 수준에 맞추어 관련 기준을 개정해야할 필요성이 대두되고 있다. 캐나다에서는 1992년에 처음 생물학적 동등성 시험 기준을 공표하여 평가하고 있다. 본 논문에서는 캐나다의 생물학적 동등성 시험 기준을 소개하여 현행 규정과 비교 검토함으로써 생물학적 동등성 시험 기준을 보다 과학적이고 윤리적이며 합리적인 규정으로 개정하기 위한 자료로 활용하고자 한다.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.64 no.3
• /
• pp.213-224
• /
• 2019

There is an increasing frequency in the occurrence of abnormal weather phenomena such as sharp increases and decreases in temperature. Under these weather conditions, the heading time of rice changes unexpectedly, which poses problems in agriculture. Therefore, we investigated the effect of temperature on the heading response at different growth stages in rice. During the period from transplanting to heading, the plants were subjected to different temperature treatments, each for a 9-day period, to observe the heading response. For the heading date analysis, "heading date" was defined as the number of days from transplanting to the appearance of the first spikelet. We found that the influence of temperature increased in the order of rooting stage, followed by meiosis, early tillering, spikelet differentiation, and panicle initiation stage in all ecological types and cultivars. In particular, unlike the results reported previously, the effect of temperature on heading during the photo-sensitive period was very small. Meanwhile, the influence of temperature on vegetative growth response at different growth stages was not consistent with heading response. These results can be used as basic data for predicting the variation in heading date owing to temperature variation at each growth stage. In addition, we propose that the concept of day length should be included in determining the influence of temperature on the photo-sensitive period.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2022.10a
• /
• pp.297-297
• /
• 2022

Wheat is the staple food crop in the word, but wheat products have a low bioavailability of iron and zinc. So in the developing world, where wheat is a staple food, it suffers from micronutrients deficiency. This study was conducted to generate wheat varieties with enhanced grain Zn and Fe contents. Sixty wheat resource were cultivated over 2 years (2019-2021) in the field of NICS, Jeonju, Republic of Korea, to identify agronomic traits. Wheat grains were ground using grinder and analyzed whole wheat flour protein contents and Fe and Zn contents using ICP-OES. The average contents of Zn and Fe grain were 4.6 mg/100g (2.4~8.8 mg/100g) and 4.5 mg/100g (2.4~7.9 mg/100g), respectively. The contents of Fe and Zn in the wheat grain had a positive correlation with the protein content of whole wheat flour, but there was no correlation with heading date (4.22~5.27) and the thousand kernel weight (21.3~57.5 g). Although there was year variation, six resources with high contents of Fe (>5.2 mg/100 g) and Zn (>5.3 mg/100 g) grain in 2 years were selected. These results provide information for selecting breeding materials for biofortified wheat, and further studies on germplasms genetic variations and bioavailability are needed.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2022.10a
• /
• pp.300-300
• /
• 2022

Wheat (Triticum spp.) is an important source of food worldwide and the focus of considerable efforts to identify new combinations of genetic diversity for crop improvement. In particular, wheat starch composition is a major target for changes that could benefit human health. Starches with increased levels of amylose are of interest because of the correlation between high amylose content and elevated levels of resistant starch, which has been shown to have beneficial effects on health for combating obesity and diabetes. In this study, high amylose wheat germplasms from other countries were collected and cultivated in Korea, and then the content of amylose was evaluated, we examined amylose content in 614 wheat germplasm. Furthermore, amylose content was validated using several milling processes such as roller, hammer, and grinding mill. As a result, the amylose content distribution was divided into five groups. The range of the amylose levels in whole wheat flour was 18.3% to 29.6%. In addition, the mutant lines were screened for high amylose, and two mutant lines (WX-1046 and WX-1074) exhibited a comparable amylose content to Keumkang whole wheat (19.6%). It has been established that high amylose indicated SS IIa null and necessitate GBSS. Based on these findings, it may be helpful to develop high amylose wheat germplasm and production techniques, particularly in Korea.

• Proceedings of the PSK Conference
• /
• 2002.04a
• /
• pp.167.2-168
• /
• 2002

• Proceedings of the Korean Society of Toxicology Conference
• /
• 2003.10b
• /
• pp.179-179
• /
• 2003

2,3,7,8-Tetrachlorodibenzo-$\rho$-dioxin (TCDD) displays high toxicity in animals and has been implicated in human carcinogenesis. Although the mechanisms of TCDD-induced carcinogenesis are poorly understood, it considered to be non-genotoxic and tumor promoter. In this study, we investigated the tumor promotion effect of TCDD on the two-stage skin chemical carcinogenesis using hairless mouse (SKH1).(omitted)