• Environmental Mutagens and Carcinogens
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• v.16 no.1
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• pp.30-34
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• 1996

This study was performed to examine the availability of using medaka (Oryzias latipes) in teratological test. Medaka embryos were collected within 2 hours post-fertilization and cultured in petri dishes containing buffered saline until hatching. The embryos were treated with 0.56 mg/l chlorpyrifos-methyl and 10 mM methyl methanesulfonate at 20 stages (about 35 hours post-fertilization). Eleven developmental features were selected and observed from 33 stages (about 9 days post-fertilization). Scoring system was developed and applicated for the measurement of potential teratological effects by the test compound. Chlorpyrifos-methyl did not induce teratological effect in medaka embryos. However, we found teratological test using medaka embryo reduced the cost, labors, period and space of experiment significantly compared with teratological study using rodents. Above findings strongly suggest that medaka embryo can be used as a lab animal model for teratogenicity test instead of rodents.

• Toxicological Research
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• v.13 no.1_2
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• pp.167-173
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• 1997

LBD-001, a recombinant human interferon $\gamma$ produced by genetically engineered yeast as a host system, was intravenously administered to pregnant female rabbits (New Zealand White strain) from day 6 to 18 of gestation at dose levels of $0.35 \times 10^6$, $0. 69 \times 10^6$, and $1.38 \times 10^6$ I.U./kg/day. Hydrocortisone sodium succinate (0.3 mg/kg/day) was also given in the same way. Teratological effects of the test agents on the organogenesis of fetuses and the development of offsprings (F1 rabbits) were investigated. The results were as followings: (1) No significant changes by the treatment of LBD-001 or hydrocortisone sodium succinate were observed in the body weights, the food and water consumption, the lactating or nurshing behaviors, and the autopsy of the pregnant rabbits. (2) No significant changes in the resorption rate, the fetal organogenesis, and the normal develpoment of offsprings (F1) by the treatment of LBD-001 or hydrocortisone sodium succinate were detected. The results show that LBD-001 at the dose of $1.38 \times 10^6$ I.U./kg/day or less and hydrocortisone sodium succinate at the dose of 0.3 mg/kg/day are neither teratogenic in the organogensis of the fetuses and the development of the offsprings (F1) nor toxic to the mother rabbits.

• Biomolecules & Therapeutics
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• v.4 no.4
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• pp.301-309
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• 1996

LBD-001, a recombinant human interferon ${\gamma}$ produced by genetically engineered yeast as a host system, was intravenously administered to pregnant female rats (Sprague-Dawley) from day 7 to 17 of gestation at dose levels of 0.35$\times$10$^{6}$ , 0.69$\times$10$^{6}$ , and 1.38$\times$10$^{6}$ I.U./kg/day. As the control groups, hydrocortisone sodium succinate (5 or 10 mg/kg/day) was also similarly administered. Teratological effects of the test agents on fetuses and development of offsprings (F1 rats) were investigated. (1) No significant changes by the treatment of LBD-001 were observed in body weight, food and water consumption, feeding and nursing behaviors, and autopsy of pregnant or lactating mother rats. However, in hydrocortisone sodium succinate (10 mg/kg/day)-treated group, significant decreases of body weight on day 16, 18, and 20 of gestation and food consumption on day 20 of gestation and outstanding atrophy of thymus and adrenals were observed in two rats autopsied on day 20 of gestation. (2) No significant changes in resorption rate, skeletal or visceral development of fetuses, and physical or sensory development of offsprings (Fl) by the treatment of LBD-001 were detected. In hydrocortisone sodium succinate (10 mg/kg/day)-treated group, however, there were significant decreases of body weight of fetuses, delay of ossification, temporary delay of body weights of offsprings (F1) on day 1 and 3 of lactation, and increased tendency of stillborn rate and malformation rate of bone. The results show that LBD-001 at the dose of 1.38$\times$10$^{6}$ I.U./kg/day or less is not teratogenic in organogenesis of fetuses and the development of offsprings (F1). Meanwhile, hydrocortisone sodium succinate (10 mg/kg/day) seems to delay ossification of fetuses and temporarily retard the development of offsprings (Fl).

• Toxicological Research
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• v.2 no.1
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• pp.9-21
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• 1986

Teratological study on pranoprofen, as antiinflammatory agent, was conducted by oral intubation in Sprague-Dawley rats. Pranoprofen was administered doses of 1.0, 2.5 and 5.0mg/kg/day and doze of 0.5mg/kg/day of Indomethacin was used as positive control. The rats were dosed from day 7 to 17 of gestation. At necropsy on day 20 of gestation, pathologically changes of gastroin-testinal system, liver and adrenal gland were examined at the high dose administered group. There were no differences between control and treated group on the number of implantations, the number of alive and dead fetuses, tail length, and external visceral and skeletal malformations.

• The Korean Journal of Applied Statistics
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• v.8 no.2
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• pp.147-161
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• 1995

The primary objective of this paper is to review parametric models and test statistics related to overdspersion of count data. Poisson or binomial assumption often fails to explain overdispersion. We reviewed real examples of overdispersion in count data that occurred in toxicological or teratological experiments. We also reviewed several models that were suggested for implementing experiments. We also reviewed several models that were suggested for implementing the extra-binomial variation or hyper-Poisson variability, and we noted how these models were generalized and further developed. The approaches that have been suggested for the overdispersion fall into two broad categories. The one is to develop a parametric model for it, and the other is to assume a particular relationship between the variance and the mean of the response variable and to derive a score test staistics for detecting the overdispersion. Recently, Dean(1992) derived a general score test statistics for detecting overdispersion from the exponential family.