• Journal of Forest and Environmental Science
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• v.29 no.3
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• pp.219-225
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• 2013

The correlation between disturbance intensity and stand development was evaluated on the basis of natural forest community type classification in areas of Baekhaksan (more disturbed area) and Hwangaksan (less disturbed area). The vegetation data were collected by point-centered quarter sampling method, and they were subjected to cluster analysis for classifying community types and to analysis of species composition and species diversity for reviewing ecological characteristics. By the method of cluster analysis, natural forests of Baekhaksan were classified into Quercus forest community, Pinus densiflora community, Q. variabilis community, and Q. mongolica community. Those of Hwangaksan were divided into P. densiflora community, Q. mongolica community, Q. forest community, and Mixed mesophytic community. It is presumed that more developed and less disturbed forest area shows multiple species community pattern and more diversified structure than less developed and more disturbed forest area. In Korean peninsula, the abundance of red pine may play an important indicator to estimate the developmental pattern of the forest after artificial disturbance. The overall evaluation indicated that less disturbed Hwangaksan area had more developed stand pattern with mixed mesophytic community, more complicated species composition, and higher species diversity than Baekhaksan area.

• Development and Reproduction
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• v.18 no.2
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• pp.117-125
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• 2014

Vitrification method is widely used in oocyte cryopreservation for IVF but the birth rates are lower than that of the fresh oocyte. One of the known main reasons is structural instability of meiotic spindle and chromosome systems of mature oocyte. To get the best way for keeping competence of matured oocytes, we studied the best conditions for vitrification focused on equilibration times. The mature oocytes were underwent vitrification with current popular method and analyzed the survival rates, microtubule stability and DNA integrity. The survival rates of recovered oocyte are almost same between groups and are more than 93%. The structural configuration of meiotic spindle was well kept in 10 min equilibration group and the stability rate was almost same with that of control. The chromosomal breakdown was observed in all experimental groups, but the chromosomal stability was higher in 10 min equilibration group than the other groups. The 10 min equilibration group showed best condition compared with the other groups. Based on these results, the equilibration time is one of the key factors in successful keeping for competence of mature oocyte. Although, more fine analysis about the effects of physical stress on oocyte during vitrification is needed to define the optimal condition, it is suggested that the optimal equilibration time to get competent oocyte in mouse is 10 min. Information acquired this study may provide insight into intracellular structural events occurring in human oocytes after vitrification and application for cryopreservation of human oocyte.

• Korean Journal of Childcare and Education
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• v.10 no.2
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• pp.213-236
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• 2014

This study is aimed at enhancing the prosocial behaviors and the positive peer play interaction of young children with developmental delays. Three children with developmental delays and three students without developmental delays who were 4-year-old students in an inclusive classroom were selected. Their homeroom teacher carried out the program with a small group of 6 children totaling 21 sessions over 3 months. The major results of this study were as follows: First, the result of both the observer and the parents' test after the program showed that the small group made positive changes on prosocial behaviors. In addition the frequency of target behaviors increased during the intervention. Second, the result of both the observer and the parents' test after the program showed that positive peer play interaction increased in the small group. Moreover the negative peer play interaction such as play disturbance and play isolation decreased. In conclusion, the thematic fantasy play program is useful for an inclusive classroom, and can be a concrete method to support inclusive education and childcare.

• Development and Reproduction
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• v.18 no.4
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• pp.187-195
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• 2014

Polycyclic aromatic hydrocarbons (PAHs), which are ubiquitous in the air, are present as volatile and particulate pollutants that result from incomplete combustion. Most PAHs have toxic, mutagenic, and/or carcinogenic properties. Among PAHs, benzo[a]pyrene (B[a]P) and dimethylbenz[a]anthracene (DMBA) are suspected endocrine disruptors. The testis is an important target for PAHs, yet effects on steroidogenesis in Leydig cells are yet to be ascertained. Particularly, disruption of testosterone production by these chemicals can result in serious defects in male reproduction. Exposure to B[a]P reduced serum and intratesticular fluid testosterone levels in rats. Of note, the testosterone level reductions were accompanied by decreased steroidogenic acute regulatory protein (StAR) and $3{\beta}$-hydroxysteroid dehydrogenase isomerase ($3{\beta}$-HSD) expression in Leydig cells. B[a]P exposure can decrease epididymal sperm quality, possibly by disturbing the testosterone level. StAR may be a key steroidogenic protein that is targeted by B[a]P or other PAHs.

• Journal of the korean academy of Pediatric Dentistry
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• v.24 no.4
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• pp.788-794
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• 1997

As one of the developmental disturbance in shape of teeth, a twinning has very rare frequency in permanent teeth. Because it is possible to diagnose the twinning by use of the radiograph, it is very important to detect this anomaly early by careful examining the radiographs. The twinning produces several orthodontic problem such as crowding, protrusion, ectopic eruption of adjacent teeth. Therefore it is necessary, in proper time, the extraction and orthodontic treatment should perform.

• Journal of mucopolysaccharidosis and rare diseases
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• v.5 no.1
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• pp.34-38
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• 2021

Prader-Willi syndrome is a complicated genetic disorder caused by a mutation on chromosome 15q11-13. The disease results in morbid obesity due to hyperphagia, growth disturbance, multiple endocrine problems from hypopituitarism, developmental delay, and cognitive or behavioral problems. Recombinant human growth hormone has been used to improve body composition and muscle mass, which plays a main role in treating patients with Prader-Willi syndrome. We describe previous studies showing the efficacy and safety of growth hormone treatment in children with Prader-Willi syndrome and provide treatment guidelines. Growth hormone therapy could be beneficial for children with Prader-Willi syndrome and improve their quality of life.

• The Journal of Korea Assosiation for Disability and Oral Health
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• v.1 no.1
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• pp.18-24
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• 2005

The purposes of this study were 1) to investigate the oral health problem of the disabled according to the handicapped types, 2) to collect the empirical data for developing and establishing the oral health policies for the handicapped, and 3) to find out the major obstacles against the dental services and oral health promotion. The handicapped subjects were collected by designed cluster sampling and interviewed with structured questionnaire in order to measure the oral health knowledge and behaviors. The subjects were attending the special schools and private or public welfare institutions for crippled disorder, encephalopathy disorder, mental retardation, visual disturbance, hearing defect, and developmental disorder. Oral examination was conducted by 13 trained dentists. 1,476 of handicapped people were finally surveyed. The results were as follows; The experiences of visiting dental office during the last one year in 18~64 year-old disabled people were 48.86% in crippled disorder, 52.50% in mental retardation, 58.24% in visual disturbance, 39.29% in hearing defect, respectively. To improve this challenging situation, we should find out the obstacles against the dental service and oral hygiene maintenance by the types of handicap, and develop the oral health policies which could support and advocate the Korean disabled.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.82-82
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• 2003

Offspring have been produced from somatic cells in a number of species. This biotechnology introduced a new phenomenon in reprogramming and differentiation of somatic cell, namely totipotency. However, birth of oversized calves and perinatal abnormalities such as increased gestation length, lack of spontaneous parturition, higher incidence of dystocia, and reduced perinatal viability of offspring are frequently observed in pregnancies of cloned bovine fetuses. Disturbance of feto-placenta has been proposed as likely causes for abnomal growth. However. Little is known the mechanism responsible for the perinatal problems. Therefore, we focused on gestation length in somatic cell nuclear recipient cows. To solve this issues, placental tissues of control and cloned bovine were obtained by a cesarean section (C-section) before 5 days of paturition. Total RNA from control and cloned bovine placenta was extractd by TRIzol reagent. GeneFishing DEG kits (Seegene) were used to identify differentially expression genes. Total RNA (3 ug) were synthesized by M-MLV reverse transcriptase (200 u/ul) with 10 uM dT-annealing control primer (ACP1) at 42C for 90 min. Then, first-strand cDNA (50 ng) was amplified using the 5 uM arbitary ACP (1-20) and 10 uM dT-ACP2 primers. Some specific expression genes were amplified, Now, we are cloning and sequencing. These finding strongly can be support to solve the problems for parturition delay in nuclear transfer cows, suggest that placenta specific proteins are key indicators for the aberration of gestation and placental function in cows.

• Journal of the korean academy of Pediatric Dentistry
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• v.37 no.4
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• pp.505-511
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• 2010

Odontoma represents 22% of all odontogenic tumors, which is characterized by slow growth pattern. Most of the odontomas usually develop during dental follicle proliferation. The growth of odontoma is limited and lesion is generally asymptomatic. It is frequently diagnosed during assessments for delayed eruption of permanent tooth and is usually founded in the second decade of life. Odontoma is usually diagnosed through radiographic views and is difficult to diagnose at the early developmental stage of odontoma. But an uncalcified developing odontoma can disturb the eruption of the tooth, so it is important to perform periodic radiographic examinations. Treatments are surgical removal and observation of odontoma followed by surgical opening or orthodontic traction of impacted tooth according to the tooth development and the location of impacted tooth. In this case, we found the radiopaque calcified odontoma in the radiographic view meanwhile follow up of the impacted tooth showing idiopathic eruption disturbance. This suggests that a developing odontoma is the cause of eruption disturbace.

• Reproductive and Developmental Biology
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• v.34 no.3
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• pp.193-199
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• 2010

We report here the production of transgenic chickens that can regulate human erythropoietin (hEPO) gene expression. The glycoprotein hormone hEPO is an essential for viability and growth of the erythrocytic progenitors. Retrovirus vector system used in this study has two features including tetracycline-controllable promoter and woodchuck hepatitis virus posttranscriptional regulator element (WPRE). The former is for to reduce the possibility of physiological disturbance due to constitutional and unregulated expression of hEPO gene in the transgenic chicken. The latter is for maximum expression of the foreign gene when we turn-on the gene expression. A replication-defective Moloney murine leukemia virus (MoMLV)-based vectors packaged with vesicular stomatitis virus G glycoprotein (VSV-G) was injected beneath the blastoderm of non-incubated chicken embryos (stage X). Out of 325 injected eggs, 28 chicks hatched after 21 days of incubation and 16 hatched chicks were found to express the hEPO gene delivered by the vector. The biological activity of the recombinant hEPO in transgenic chicken serum was comparable to its commercially available counterpart. The recombinant hEPO in transgenic chicken serum had N- and O-linked carbohydrate simillar to that produced from in vitro cultured cells transformed with hEPO gene.