• Environmental Analysis Health and Toxicology
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• v.25 no.2
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• pp.145-151
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• 2010

Perfluorinated chemicals (PFCs) is a kinds of persistent organic pollutants, and have the potential toxicity of which is causing great concern. In this study, we employed Oryzias latipes embryos to investigate the developmental toxicity of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA)s compound using flowthrow system for 14 day. O. latipes embryos were exposed to solvent control, 20, 40 and 80 mg/L of PFOS and 62.5, 130, 260 mg/L of PFOA respectively. After exposure, hatchability, mortality, total length and heart beats were examined. Hatching rates were reduced approximately 27% in the 80 mg/L PFOS-treated group and 17% in the 62.5, 130 mg/L PFOA-treated groups. Heart beats in the PFOS-treated groups were reduced at 7 day but, PFOA-treated groups were increased heart beats. 80 mg/L PFOS treated group showed significant reduction in growth (total length) level to 90% of control. But PFOA did not showed significant effect on growth. In the 14 days $LC_{50}$ of PFOS and PFOA was 22.74 mg/L and 173 mg/L, respectively. The overall results indicated that the early stage of O. latipes might be a reliable model for the testing of developmental toxicity to perfluorinated chemicals.

• Korean Journal of Veterinary Research
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• v.38 no.2
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• pp.394-400
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• 1998

Cryopreservation of embryos by vitrification is a simple method to preserve bovine embryos for subsequent embryo transfer, but embryonic viability after vitrification has been inconsistent and low compared with conventional slow freezing. The aim of the present study is to examine the effect of serum or serum albumin in a vitrification solution and epidermal growth factor(EGF) or fibroblast growth factor(FGF) on in vitro viability of bovine blastocysts frozen by vitrification. Bovine blastocysts were produced by in vitro maturation, fertilization of follicular oocytes and culture of embryos in a synthetic oviduct fluid medium(SOFM) containing BSA and 19 essential and nonessential amino acids. Blastocysts with excellent or good morphology were selected at 7 or 8 days after culture and utilized for vitrification. In experiment 1, blastocysts were vitrified in a solution containing semi-fetal calf serum(SFCS) or BSA(5 or 10mg/ml) and then their subsequent viabilities were examined by culturing thawed embryos in a SOFM containing BSA and 19 amino acids. Effect of EGF or FGF added to a SOFM containing polyvinyl alcohol(PVA) on the viability of vitrified-thawed blastocysts was investigated in experiment 2. BSA added at 5 or 10mg/ml to a vitrification solution showed significantly higher(p < 0.05) developmental rate to expanded and hatching blastocysts than SFCS, but there was no significant difference in the developmental rate to hatched blastocysts after thawing. Supplementation of a culture medium with EGF and/or FGF significantly increased(p < 0.05) embryo development to expanded blastocysts compared with control but showed no beneficial effect on the development to hatching or hatched blastocysts. Coculture of thawed embryos with granulosa cells in a TCM 199 containing 10% fetal calf serum(FCS) showed the highest developmental rate to expanded, hatching and hatched blastocysts among the groups tested. In conclusion, supplementation of a vitrification solution with BSA at 5mg/ml and culture of thawed blastocysts in a medium containing EGF and/or FGF can improve in vitro viability of bovine blastocysts frozen by vitrification.

• Journal of Korean Society of Forest Science
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• v.95 no.2
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• pp.174-176
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• 2006

The experiments were conducted by supplying hosts with natural food(chestnut, peach, Quince). The developmental difference of peach pyralid moth, Dichocrocis punctiferalis was examined in the laboratory under three different natural food regime. The periods of egg, larva and pupa were $6.01{\pm}0.07$, $12.23{\pm}0.03$ and $13.32{\pm}0.01$ days on the chestnut fruit, $6.21{\pm}0.01$, $18.69{\pm}0.02$ and $13.38{\pm}0.03$ days on the peach fruit and $7.02{\pm}0.04$, $22.62{\pm}0.04$ and $13.44{\pm}0.14$ days on the quince fruit, respectively. The growth of D. punctiferalis larva was better chestnut fruit than other tested fruits. The rates(%) of hatching, pupation and emergence were 94.0, 57.0 and 63.3 on the chestnut fruit, 89.2, 77.8 and 85.7 on the peach fruit and 79.6, 52.6 and 70.7 on the quince fruit, respectively. The survival rate(%) of D. punctiferalis from hatching to emergence were 31.0 on the chestnut fruit, 4.8 on the peach fruit and 14.3 on the quince fruit, respectively. The sex ratio (female: male) of all pupae obtained on the tested natural food fruits were 52.7 : 47.3. The sex ratio of D. punctiferalis reared on three difference food fruits were no significantly. It can be used a as the basic research for the study of D. punctiferalis.

• Child Studies in Asia-Pacific Contexts
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• v.4 no.1
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• pp.27-45
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• 2014

The present study investigated the developmental pattern of Korean mothers' depressive symptoms from a week prior to birth through four months postpartum in a nationally represented survey sample in Korea, using a Latent Growth Curve model. Mother-reported four factors-maternal self-efficacy in parenting, father's participation in childcare, a number of hours mothers worked per week, child's emotional temperament-were examined as the predictors of depressive symptoms over time in the context of Korean culture. Effects of maternal depressive trajectories on their infants' developmental outcomes at the first year were also examined. Findings were as follows: First, mothers' reports of depressive symptoms decreased at the first month after birth and then increased again during the first 4 months postpartum. Second, mothers' perceived low spousal involvement in childcare, low parental self-efficacy, and their infants' difficult temperament at four-month old had significantly positive relations to the initial level of maternal depressive symptoms whereas the low spousal involvement in childcare and low maternal self-efficacy factors significantly predicted the changes of trajectories of maternal depressive symptoms. Third, the trajectories, in turn, predicted warm and responsive maternal parenting style at the fourth month. Subsequently, the parenting style had a significant longitudinal impact on the development of children's communication, problem-solving, and personal-social abilities. Based on these findings, awareness, preventive and interventional programs might be built to facilitate Korean mothers suffering severe postpartum depressive symptoms and further promote optimal early development of Korean children.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.30 no.2
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• pp.85-99
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• 2004

Purpose: This study observed the changes in the telomerase activity, it's developmental regulation, PCNA expression, and their correlation in rat's upper digestive organs during growth and aging. Materials and Methods: Upper digestive organs(buccal mucosa, gingiva, palate, submandibular and parotid glands, and tongue) were aseptically removed from Sprague-Dawley rats of fetal(gestational 20 days), growing(1, 2, 3, 5, and 7 weeks after birth) and adult(12 week old). Samples for telomerase activity were frozen on liquid nitrogen immediately after sacrifice, and stored until the use at $-75^{\circ}C$ in order to measure it. Telomerase activity was measured by a PCR-based telomeric repeat amplication protoco(TRAP) assay and quantitated with Photometric Telo TAGGG Telomerase PCR ELISA plus(Roche Diagnostics GmbH. Mannheim. Germany). PCNA expression were measured immunohistochemistry with anti PCNA Ab-1, Clone PC10(NeoMark. California. USA). Results: 1. Telomerase activities in buccal mucosa, palate and gingiva were the highest in fetus and decreased gradually or rapidly after birth and then diminished, but In salivary gland and tongue were the highest in fetus and also high at 1 week and then decreased rapidly. 2. PCNA expression in buccal mucosa, gingiva, Tongue and salivary gland was the highest in fetus and decreased gradually and then diminished. but only in palate decreased rapidly after birth and then diminished. Conclusion: The highest telomerase activity of embryonic stage decreased rapidly after birth in rat's upper digestive organs. There may be a developmental regulation of telomerase activity, but not a tissue-specific. This telomerase activity seems correlated closely with PCNA expression in rat's upper digestive system.

• Investigative Magnetic Resonance Imaging
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• v.19 no.3
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• pp.146-152
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• 2015

Purpose: The purpose of this study was to evaluate the associated brain parenchymal abnormalities of developmental venous anomalies (DVA) with susceptibility-weighted image (SWI). Materials and Methods: Between January 2012 and June 2013, 2356 patients underwent brain MR examinations with contrast enhancement. We retrospectively reviewed their MR examinations and data were collected as per the following criteria: incidence, locations, and associated parenchymal signal abnormalities of DVAs on T2-weighted image, fluid-attenuated inversion recovery (FLAIR), and SWI. Contrast enhanced T1-weighted image was used to diagnose DVA. Results: Of the 2356 patients examined, 57 DVAs were detected in 57 patients (2.4%); 47 (82.4%) were in either lobe of the supratentorial brain, 9 (15.7%) were in the cerebellum, and 1 (1.7%) was in the pons. Of the 57 DVAs identified, 20 (35.1%) had associated parenchymal abnormalities in the drainage area. Among the 20 DVAs which had associated parenchymal abnormalities, 13 showed hemorrhagic foci on SWI, and 7 demonstrated only increased parenchymal signal abnormalities on T2-weighted and FLAIR images. In 5 of the 13 patients (38.5%) who had hemorrhagic foci, the hemorrhagic lesions were demonstrated only on SWI. Conclusion: The overall incidence of DVAs was 2.4%. Parenchymal abnormalities were associated with DVAs in 35.1% of the cases. On SWI, hemorrhage was detected in 22.8% of DVAs. Thus, we conclude that SWI might give a potential for understanding of the pathophysiology of parenchymal abnormalities in DVAs.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.3
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• pp.340-345
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• 2008

Oxidative stress is one of the major causes of failure of in vitro storage of boar semen. Reactive oxygen species (ROS) are one of the important mediators of oxidative stress during in vitro storage of boar semen. Our study examined the effects of taurine on sperm characteristic and on in vitro developmental embryos during in vitro storage of boar semen for 7 days. Semen was randomly aliquoted into 3 centrifuge tubes and treated with different concentrations of taurine (25-100 mM). The characteristics of boar sperm were analyzed for motility by light microscopy, viability by using a Makler counting chamber and membrane integrity by a hypoosmotic swelling test (HOST). The percentages of motile spermatozoa in taurine groups after 5 days were significantly higher compared to the control. Sperm viability in the control was lower than in taurine groups after 7 days irrespective of different taurine concentration. In the hyoosmotic swelling test (HOST), significantly higher results were obtained in taurine groups after 3 days. Also, the developmental rates of IVM/IVF porcine embryos from semen treated with pyruvate and taurine were significantly increased when compared with the control (p<0.05). These results indicate that supplementation of taurine as an antioxidant in boar semen extender can improve the semen quality.

• Development and Reproduction
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• v.18 no.3
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• pp.139-143
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• 2014

Different with other fishes, the guppies (Poecilia reticulata) is ovoviviparity, which retain their fertilized eggs within the follicle throughout gestation. The synchronously growing diplotene oocytes store nutrients in droplets and yolk, before their maturation and fertilization. The lecithotrophic strategy of development entails the provisioning of embryos with resources from the maternal yolk deposit rather than from a placenta, it allows the extracorporeal culture of guppy embryo. Studies on their early development of live bearers like the guppy including lineage tracing and genetic manipulations, have been limited. Therefore, to optimize conditions of embryo in vitro culture, explanted embryos from pregnant females were incubated in embryo medium (L-15 medium, supplemented with 5, 10, 15, 20% fetal bovine serum, respectively). We investigated whether the contents of FBS in vitro culture medium impact the development of embryos, and whether they would hatch in vitro. Our study found that in 5% of FBS of the medium, although embryos developed significantly slower in vitro than in the ovary, it was impossible to exactly quantify the developmental delay in culture, due to the obvious spread in developmental stage within each batch of eggs, and embryos can only be maintained until the early-eyed. And although in culture with 20% FBS the embryos can sustain rapid development of early stage, but cannot be cultured for the entire period of their embryonic development and ultimately died. In the medium with 10% and 15% FBS, the embryos seems well developed, even some can continue to grow after follicle ruptures until it can be fed. We also observed that embryonic in these two culture conditions were significantly different in development speed, in 15% it is faster than 10%. But 10% FBS appears to be more optimizing condition than 15% one on development process of embryos and survival rate to larvae stage.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.89-89
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• 2017

A gene encoding squalene synthase from grain amaranth was cloned and characterized. The full-length cDNA was 1805-bp long and contained a 1248-bp open reading frame encoding a protein of 416 amino acids with a molecular mass of 47.6 kDa. Southern blot analysis revealed that the A. cruentus genome contained a single copy of the gene. Comparison of the cDNA and genomic sequences indicated that the amaranth SQS gene had 12 introns and 13 exons. All of the exons contributed to the coding sequence. The predicted amino acid sequence of the SQS cDNA shared high homology with those of SQSs from several other plants. It contained conserved six domains that are believed to represent crucial regions of the active site. We conducted qRT-PCR analyses to examine the expression pattern of the SQS gene in seeds at different developmental stages and in several tissues. The amaranth SQS gene was low levels of SQS transcripts at the initial stage of seed development, but the levels increased rapidly at the mid-late developmental stages before declining at the late developmental stage. These findings showed that the amaranth SQS is a late-expressed gene that is rapidly expressed at the mid-late stage of seed development. In addition, we observed that the SQS mRNA levels in stems and roots increased rapidly during the four- to six-leaf stage of development. Therefore, our results showed that the expression levels of SQS in stem and root tissues are significantly higher than those in leaf tissues. In present study provides useful information about the molecular characterization of the SQS clone isolated from grain amaranth. Finally, a basic understanding of these characteristics will contribute to further studies on the amaranth SQS.

• Physical Therapy Korea
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• v.15 no.3
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• pp.1-7
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• 2008

Multi-sensory systems, including the visual, somatosensory, and vestibular ones, are involved in maintaining standing balance. The organization of these sensory systems is as important as the efficiency of each individual system in maintaining optimal balance. The purpose of the present experiment was to investigate the developmental changes in static standing balance and sensory organization under altered sensory conditions. This study involved 64 children (from 4 to 15 years of age) and 17 young adults. The children were divided into four age groups: 4~6, 7~9, 10~12, and 13~15 years. Static standing balance was assessed with the one-leg standing test under four different sensory conditions: the children stood on a firm surface with (1) eyes open or (2) closed, and they stood on a foam surface with eyes (3) open or (4) closed. In balancing ability, the age groups exhibited significant differences. The function of sensory organization for balance control was poorer for the children than for the young adults. The functional efficiency of the somatosensory system of the children aged 7~9 years was at the young adults' level, and the visual function of the children aged 10~12 years had also reached the young adults' level. However, the functional efficiency of the vestibular system of children was significantly lower than that of the young adults, even at the age of 15 years. This may indicate that sensory organization and standing balance are still developing after the age of 15 years.