• Proceedings of the Korean Society of Environment and Ecology Conference
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• 2002.04a
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• pp.80-81
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• 2002

• The Korean Journal of Zoology
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• v.32 no.3
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• pp.258-263
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• 1989

Nuclear Transplantation between Rana pipiens and Rana dybowskii When diploid blastula nuclei of Rana pipiens are traraplanted into enucleated eggs of Rana dybowskii the resulting nucleocytoplasmic hybrids are lethal-those development were arrested around the stage of the dorsal lip formation For the improvement of developmental capacity, serial nuclear transplantation was carried out. Even though serial transplantation of 15 generations showed normal development in each generation until gastrula stage, there was no sign of fundamental improvement in development afterward. This results implied that up to gastrulation normal DNA replication and cell division can take place in foreign cytoplasm. Since chromosomal aberrations both in shape and number were usually observed, the nuclei must have been modifted while resided in the foreign cytoplasm. Those nuclei didn't participate in normal development and led the embryos to early death. Tissue graft experiment indicated that the abnormal behavior of this lethal nucleocytoplasmic hybrid is an inherent property which is not corrected by the contact with its own tissue.

• Korean Journal of Environment and Ecology
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• v.18 no.3
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• pp.340-345
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• 2004

The embryotoxic effects of PCB (Aroclor 1248) on a Korean frog, Rana dybowskii was deter-mined by using the FETAX (Frog Embryo Teratogenesis Assay-Xenopus) protocol. The rates of mortality and malformed larvae were investigated by probit analysis. The results showed that PCB is highly embryolethal. From LC$_{50}$ of 1.48ppb and from EC$_{50}$ of 0.25ppb and TI of 5.7 were derived, which indicates PCB is to be considered a teratogenic compound. Specific malformations occurred in 62.0% as edema at the 0.1ppb, in 32.0% as tail deformations at the 1ppb, and in 68.0% as profound deformations at the 5ppb of PCB concentration which living embryos were exposed to. PCB suppressed the growth of head-tail length at a relatively low concentration (1.0ppb), and therefore growth inhibition as assessed by embryo length can be used as a sensitive indicator to evaluate the toxicity of pollutants in the environment. In conclusion, PCB must be considered highly embryotoxic to Rana dybowskii.

• The Korean Journal of Zoology
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• v.26 no.3
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• pp.193-202
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• 1983

Inversion at variable time of the uncleaved eggs of Rana nigromaculata and Rana dybowskii was emplyed to study the mechanisms of early embryogenesis. The response to inversion varied between those two spcies. If the eggs were inverted at early time it was possible to change the site of the first cleavage furrow of Rana nigromaculata-it appeared on the original vegetal hemisphere (OpG side). However, the first cleavage furrow of Rana dybowskii was not changed at all no matter what its inversin time was-it always appeared on the original animal hemisphere (G. side). In the inverted Rana nigromaculata embryos the size of the blastomeres on the vegetal hemisphere was always smaller than those of animal hemisphere. On the ocntrary, the cleavage pattern of Rana dybowskii was not altered. Results of the histological works for the inverted eggs suggest that the different responses to inversion might be caused by the fact that the extent to which the redistribution of the egg components such as cleavage nuclei and yolk platelets are different.

• The Korean Journal of Zoology
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• v.34 no.2
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• pp.188-195
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• 1991

The effect of lanthanum ion (La3 +), which is associated with the mobilization of internal calcium, on the regulation of oocyte maturation was investigated with Rana dybowskii follicles. Follicular oocytes matured (germinal vesicle breakdown, GVBD) dose dependently when they were exposed to La3+ (O.O1-1.O mM) and the maturation occurred in 9-12 hours after the la3+(0.33 mM) stimulation. lanthanum also accelerated the onset of maturation of the lollicular oocytes exhibiting spontaneous maturation. Three hours of exposure to La3+ was enough to induce the maturation. The La3 + -induced maturation was not associated with progesterone production by follicle cells, and the maturation was inhibited by forskolin (9 $\mu$ M), and cyclobeximide (0.01 - 1.0 - $\mu$g/2 ml) in the medium. The La3+ and hormone stimulated maturation showed the same patterns of protein phosphorylation and dephosphorylation during the maturation. The data suggest that the oocyte maturation by La3+ stimulation is very similar to that by progesterone. Thus, it seems that internal mobilization of Ca2+ plays a key role in the initiation of oocyte maturation in amphibia.

• The Korean Journal of Zoology
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• v.38 no.4
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• pp.449-456
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• 1995

Seasonal changes in the activity and charaderistics of brain Na+, K+-ATPase and Mg2+-AWase were investigated in frog (Rana dybowskii) The brain Na+, K+-ATPase adivity during hibernation was similar to that in active period in frogs. The Na+, K+-AWase activity increased in December and March, when the frogs enter into and awake from the hibernation. Over 5-35$^{\circ}C$ temperature range, Na+, K+-ATPase showed non4inear Arrhenius kinetics throughout the year. The brain Mg2+-ATPase activity decreased during hibernation, but markedly increased in March. The Arrhenius plots for Mg2+-AWase activity were linear in frogs both in torpid and active state. The ratio of Na+, K+-AWase activity at 15~C to at 35~C did not change during hibernation. The sensitivity of Na+, K+-AWase to ouabain was also unchanged throughout the year. These results indicate that the activity and charaderistics of brain Na+, K+-AWase remain unchanged during hobernadon in frog.

• Journal of Wetlands Research
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• v.17 no.4
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• pp.407-413
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• 2015

As the number of applications containing nanomaterials increase, aquatic ecosystem exposure to nanoparticles (NPs) is unavoidable. In this study, we carried out toxicity assessment to Au-nanoparticles(NPs) of Rana dybowskii eggs and tadpoles. Toxicity was recorded hatching rate, body condition(Snout-tail length, STL), and behavioral sensitivity. Behavioral sensitivity was analyzed to anti-predator behavior using Ethovision XT 9. Au-NPs did not show any toxicity of hatching rate and STL. But, Tadpoles exposed to Au-NPs decrease behavioral sensitivity of stimuli. This study has value of environmental toxicity evaluation because these results show the new way of toxicity assessment.

• Korean Journal of Environment and Ecology
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• v.11 no.1
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• pp.84-99
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• 1997

Amphibian and Reptilian specimens which were surveyed in Gyebangsan during both from Apr. 26, 1995 to Oct. 15, 1995 and from Apr. 13, 1996 to July 28, 1996 were observed 9 Species in 5 Families on 2 Orders and 10 Species in 3 Families, 5 Fimilies, 9 Species and Reptiles were 2 Suborders, 3 Families on 2 Suborders, respectively. Bombina orientalis was revealed dominant species and Bufo stejnegeri was distributed abundant on this investigation area than other survey studies. Relatively large number of larvae of Rana dybowskii were found among the stream and small ponds at the Suchung-gol valley. There were 5 species of Specific wildlife species in Korea as Hynobius leechii, Rana dybowskii, Onchodactylus fischeri, Bufo stejnegeri and Bufo bufo gargarizans. Meanwhile Bufo stejnegeri were endemic species in Korea. 6 Species among 10 Species which were observed Reptiles in this survey Scincella laterale laterale, Dinodon rufozonatus rufozonatus, Agkistrodon brevicaudus, Agkistrodon saxatilis, Amphiesma vibakari ruthveni and Enhydris rufodorsata were Specific wildlife in Korea. Scincella laterale laterale and Takydromus amuriensis were habitated very abundant in Suchung-gol region. Habitat density of Takydromus amureinsis at Suchung-gol region was 36 individuals/ha. Total number of pressed to death individuals caused by press on the road from May to July, 1995 were 404 specimens in 10 Species. The 1,2,3 and 4 Stations where were found the largest number of death individuals caused by press on the road should considered to construct Eco-corridor to reduced the death individuals with small pipes beneath the road as a migration route. Onchodactylus fischeri have around 500m as moving distance and home range for lifelong and it were the climax of broad-leaved tree and highly moisture area that abundantly region of Onchodactylus fischeri.

• Korean Journal of Environment and Ecology
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• v.18 no.3
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• pp.333-339
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• 2004

The Frog Embryo Teratogenesis Assay-Xenopus(FETAX) protocol was recently adopted as a valuable tool fur evaluating chemical toxicity and the effect of environmental contaminants in frogs. In this study, the teratogenecity of NiCl$_2$, Carbofuran, Diazinon were determined in the Korean frog, Rana dybowskii using the FETAX protocol. The mortality rate and the percentage of malformed larvae were investigated by probit analysis, The teratogenic concentrations(EC$_{50}$) of NiCl$_2$, Carbofuran and Diazinon were 0.4 and 1.6 and 1.9 mg/1. The embryolethal concentrations(LC$_{50}$) of NiCl$_2$, Carbofuran and Diazinon were 17.6 and 41.5 and 20.2mg/1. The teratogenic indices (TI=LC$_{50}$/EC$_{50}$) were 43.8 for NiCl$_2$, 26.0 for Carbofuran and 10.6 for Diazinon. NiCl$_2$, Carbofuran and Diazinon were shown to be potent teratogens for Rana dybowskii embryo, causing concentration related increase of edema, tail and abdomen. The study results reveal that NiCl$_2$, Carbofuran and Diazinon suppress the development of embryos at relatively low concentrations. Therefore, the Rana dybowskii embryo teratogenesis assay system was proven to be a useful tool to evaluate the toxicity of environmental pollutants.lutants.

• Proceedings of the Zoological Society Korea Conference
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• 1998.10b
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• pp.156.1-156
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• 1998

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