• 약학회지
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• 제45권2호
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• pp.190-204
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• 2001

This study was conducted to investigate for its effects on reproductive and developmental toxicity of recombinant human epidermal growth factor (rhEGF) in Sprague-Dawley rats. Male rats were administered rhEGF at doses of 1, 10, 100, and 1000$\mu$g/kg/day, respective1y, by subcutaneous injection from 63 days before and throughout to mating period until the day before sacrifice. Female rats were administered rhEGF at the same doses from 14 days before mating to day 20 of gestation or to day 21 of lactation. We examined the male and female fertility indices and maternal toxicity of F0 parental animals. Also, we examined the external, visceral, or skeletal malformation of fetuses, growth and development, behavior, and/or reproductive performance of F1 animals. At the highest dose (1,000 $\mu$g/kg), the mean body weights of F0 animals were significantly increased in males and females at 3 or 2 weeks after treatment, respective1y. No clinical signs and food intakes were observed at any time during the experimental period by rhEGF treatment. In autopsy examination, the relative and absolute liver weights significantly increased in both sexes of 1,000 $\mu$g/kg. At the highest dose (1,000 $\mu$g/kg), there was a statistically significant increase of pregnancy period and the number of dead fetuses. Moreover, significant increase of mean fetal body weight and decrease of number of live fetuses, which related to the difficult dilivery were observed in highest dose group. In Fl examination, no adverse effects on external, visceral, and skeletal malformation, physical and functional development, behavior or reproductive ability of Fl animals were observed in any group. Also, there was no significant difference between control and treated groups in copulation or fertility indices of Fl animals. These results indicate that rhEGF had no adverse effect on fertility and reproductive ability of Sprague-Dawley rats.

• Animal cells and systems
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• 제16권5호
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• pp.425-430
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• 2012

The southwestern Australian frog Crinia georgiana (Anura; Myobatrachidae) inhabits ephemeral pools in which the tadpoles often face desiccation. Under these conditions selection on tadpoles can be severe and can directly affect fitness during the aquatic as well as the terrestrial developmental stages. A quantitative genetic study using a half-sib breeding design was conducted to understand the genetic effects on larval life-history traits. We found no significant additive genetic variance in any of larval traits. Except for hatching period, heritability estimates based on females were high in egg size, larval period, snout-vent length, and weight at metamorphosis, suggesting non-additive genetic effects. These results indicate that any response to selection during hatching and larval periods should be predominately governed by non-additive genetic effects in C. georgiana.

• 한국발생생물학회지:발생과생식
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• 제25권3호
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• pp.145-155
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• 2021

Reproductive cycle of the blue-striped angelfish, Chaetodontoplus septentrionalis were histologically investigated. Fish were monthly collected in the coastal waters of Munseom, Seogwipo, Jeju-Island from February to December 2018. The gonadosomatic index (GSI) increased from May and maintained high values in August. The reproductive cycle of female fish can be classified by the characteristics observed during gonadal development as followed: growing stage (November to June), early mature stage (May to June), mature and spawning stage (June to September), and degenerative and recovery stage (September to December). In the male, testicular development period was similar to that of ovarian development period, but mature and spawning period was one month longer from June to October. Fecundity of mature female ranged from 4,601 to 22,840 and was correlated positively with total length and body weight. The histological analysis of gonadal development indicated that the C. septentrionalis was summer-spawning type and is considered a multiple spawner during spawning season.

• 한국동물학회지
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• 제37권4호
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• pp.478-487
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• 1994

The developmental changes of three enteroendocrine cells, i.e. gastrln, somatostatin and serotonin, of gastric and small intestinal mucosa in pre- and postnatal rat were examined by peroxidase-antiperoxidase (PAP) method. In the course of development, gastrin cells were obsenred in the pyloric gland region and the whole part of small intestine, while somstostatin and serotonin cells in the whole gastric gland region and small intestine. More entroendocrine cells were detected in the pyloric gland region and duodenum than in the other portion. In the stomach, gastrin, somatostatin and serotonin ceils were first obsenred in the pyloric Bland region on 17, 19 and 19 days of gestation respectively. The small intestinal gastrin and serotonin cells were first appeared in the duodenum and iriunum on 17 and 15 days of gestation respectively, and somatostBtin cells in duodenum on 17 days of gestation. The number of cells examined from the stomach were increased from fetal to weanling period and showed a decrease during adult period: the notable increase was shown at the end of suckling period or at early weanling period. The cells of the small intestine increased from fetal to suckling period, especially, these cells markedly increased at the end of fetal period or at early suckling period, and decreased from weanling period. The shape of these cells was oval or fusiform during fetal period. In the stomach, most of gastrin cells turned out to be oval and open-type from suckling period, while the remaining two tripes of cells were oval and open- or closed-type. In the small intestine, 311%Ves of cells examined were changed to fusiform and open-type from the end of fetal period. Three types of cell were distributed over the stratified epithelium on 15 and 17 days of gestation. In the stomach, these cells were distributed lower gastric pit and gland from the following fetal period, and were detected mainly on the upper part of gland from suckling period, and then obsenred on the whole part of gland. In the small intestine, most of cells distributed over only between epithelium of villi on 19 days of gestation, increased in number on the crypt from following fetal period, and also observed abundantly in the crypt at adult period.

• 한국발생생물학회지:발생과생식
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• 제18권2호
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• pp.107-115
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• 2014

Cardiovascular system is the primary organ to develop and reach a functional state, which underscores the essential role of the vasculature in the developing embryo. The vasculature is a highly specialized organ that functions in a number of key physiological works including the carrying of oxygen and nutrients to tissues. It is closely involved in the formation of heart, and hence it is essential for survival during the hatching period. The expression of genes involved during vascular development in the olive flounder (Paralichthys olivaceus) in the days after hatching is not fully understood. Therefore, we examined the expression patterns of genes activated during the development of flounder. Microscopic observations showed that formation of blood vessels is related to the expression of the vimentin gene. Also, the temporal expression patterns of this vimentin-like gene in the developmental stages and in the normal tissues of olive flounder. The purpose of this study was to examine the expression patterns of vimentin in normal tissues of the olive flounder and during the development of the vascular system in newly hatched olive flounders and HIF-1 plays a vital role in the formation of blood vessels during development. Vimentin expression was strong at the beginning of the development of blood vessels, and was present throughout all developmental stages. Our findings have important implications with respect to the roles of vimentin and HIF-1 in the development and evolution of the first blood vessels in olive flounder. Further studies are required to elucidate the vimentin-mediated hypoxic response signal transduction and to decipher the functional role of vimentin in developmental stages.

• 한국환경보건학회지
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• 제44권5호
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• pp.468-479
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• 2018

Objectives: Recently, a report was published that the humidifier disinfectant CMIT/MIT did not cause developmental toxicity and was not detected in systemic circulation as a result of an inhalation toxicity test. Therefore, this study was carried out to investigate any associations between CMIT/MIT exposure and developmental toxicity using the in vivo apical toxicity test method. Methods: Groups of pregnant ICR mice were instilled in the trachea with chloromethylisothiazolinone/methylisothiazolinone (CMIT/MIT) using a visual instillobot over a period of seven days from days 11 to 17 days post-coitum. For the in vivo apical toxicity test method, an $LD_{50}$-based dose-range finding model was applied to decide the dose range for inducing developmental toxicity. Results: Among the groups of 0, 0.1, 0.5, 1.0, and 1.5 mg ai/kg/day CMIT/MIT, the exposure groups of 0.5 mg and 1.0 ai/kg/day CMIT/MIT were estimated to reflect the thresholds for the stillbirth and death of pregnant mice, respectively. The groups of 0.5, 1.0, and 1.5 mg ai/kg/day CMIT/MIT induced stillbirth rates of 2.57, 10, and 53.8%, respectively. Another exposure group of 0.75 mg ai/kg/day CMIT/MIT did not induce any deaths of pregnant mice and resulted in a stillbirth rate of 8% in only one of six pregnant mice. Conclusions: CMIT/MIT can induce stillbirth in pregnant mice. It was also concluded that CMIT/MIT moves through the pulmonary circulation system and then continues on through systemic circulation and the placenta. There is a possibility of stillbirth and other health causalities in humans beyond the lungs caused by CMIT/MIT exposure.

• International Journal of Industrial Entomology and Biomaterials
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• 제38권2호
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• pp.38-50
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• 2019

We investigated the developmental characteristics and life cycle of the lawn cutworm, Spodoptera depravata (Lepidoptera: Noctuidae), which is one of the most important pests causing economic damage in grass production. For larval culture, we provided the zoysiagrass at $25^{\circ}C$ and $60{\pm}5%$ humidity. The durations of the developmental stages were as follows: $4.11{\pm}0.19$ days for eggs, $25.17{\pm}3.02$ for larvae, $8.80{\pm}0.28$ for pupae, and $7.57{\pm}0.95$ for adults. We grew the larvae to the 7th instar stage, unlike previous studies, in which it was assumed that the 6th instar was the final age. There was a significant positive correlation between the body length and head capsule width of each instar larvae. In terms of morphology, the eggs changed from light green immediately following oviposition to black as they developed, and the grass-fed larvae changed from light yellow immediately after hatching to green as development continued. We observed a pattern of black spots at regular intervals on the dorsal sides of the abdomens of the final instar larvae. Furthermore, we detected two notable designs on the dorsal side of the front of the head. The pupal colors changed from light brown and green immediately after pupation, to dark brown as the pupal cuticle hardened. The wingspans of the adults were similar in both sexes. However, the forewings of the males had obvious outer lines and eyespots with dark gray-brown backgrounds, whereas the corresponding features on the female forewings were less obvious. The oviposition preperiod was 2.11 days, the oviposition period was 4.2 days, the average fecundity per female was approximately 341 eggs, and the hatching rate was approximately 76.1%.

• 문화기술의 융합
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• 제4권4호
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• pp.107-114
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• 2018

전환기의 발달장애학생이 여가활용 교과과정을 통해 스스로 여가를 찾고, 즐길 수 있는 능력을 함양하고, 지역사회 프로그램을 통해 실제 지역사회 여가의 자원들을 활용할 수 있는 독립적인 능력을 적용하기 위해서는 여가활용의 교과과정과 지역사회 자원의 연결이 구비되어야 한다. 이를 위해서는 교과과정으로서의 여가활용을 지도하는 교사의 여가활용 인식이 전제가 되며, 지역사회 기반의 여가활동 참여시 언급되는 개선점과 중요도에 대한 검토가 필요하다. 발달장애인의 평생계획과 관련한 최근의 연구들은 기존 요소에서 여가활동을 확장하고 있으며, 이는 총체적인 측면에서의 준비가 필요함을 의미하고 있다. 본 연구는 문헌자료를 바탕으로 발달장애학생의 여가활동의 중요한 자원으로서 학교 현장에서의 여가활동과 지역사회여가활동의 중요성에 초점을 맞추고, 여가활동의 접근성을 높일 수 있는 지원방안을 제공하고자 한다.

• 대한장애인치과학회지
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• 제15권1호
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• pp.89-93
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• 2019

본 증례 보고는 기관 삽관 경험이 있는 조산아에서 상악 유전치의 발육장애가 나타난 증례이다. 본 증례들에서는 기관 삽관으로 인해 치관 형태 이상, 법랑질 결함, 맹출 지연이 나타났다. 또한 치배의 변위로 인한 맹출 경로 이상, 치근 만곡, 후속 영구치의 비정상적인 치근 형성도 나타났다. 이환 치아에 대해서는 예방적 수복치료 및 관리, 적절한 시기에 발치를 고려해야 한다. 소아치과의사는 삽관 경험이 있는 조산아에서 나타날 수 있는 상황에 대해 이해하고, 적절한 개입을 통해 구강 건강 증진을 도모해야 한다.

• 대한감각통합치료학회지
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• 제19권3호
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• pp.1-12
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• 2021

목적 : 환경 강화 치료 프로그램이 발달지연 아동의 과제수행 및 감각처리에 미치는 효과를 알아보고자 하였다. 연구방법 : 본 연구는 발달지연 소견을 보이는 아동 2명을 대상으로 단일대상연구 ABA 설계로, 진행하였으며, 중재는 주 7회씩 4주간 시행되었다. 두 아동 모두 중재 후 과제 수행도와 감각처리 변화를 확인하였다. 결과 : 중재 후 과제 수행도는 기초선 기간에 비해 평균 200%에서 최대 354%까지 향상되었으며, 감각처리영역에서도 촉각처리, 감정반응, 활동수준에 영향을 미치는 시각입력 조절영역의 점수가 정상범주로 향상되었다. 결론 : 본 연구를 통해 환경 강화 치료 프로그램이 발달지연 아동의 과제 수행 및 감각처리에 효과적이라는 점을 확인하였으며, 가정에서도 시행할 수 있는 프로그램으로 그 유용성을 확인하였다.