• Journal of Integrative Natural Science
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• v.16 no.2
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• pp.69-74
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• 2023

In Dictyostelium , there are 15 Ras subfamilies, including 11 Ras, 3 Rap, 1 Rheb. The Ras proteins are involved in regulating various cell processes as switch proteins. The functions of many Ras proteins have been identified, but some of Ras proteins have not yet been identified. Here, we focused on identifying the roles of RasW among them. To investigate the functions of RasW in cell morphology, cell migration, and development in Dictyostelium , we compared the phenotypes of wild-type cells and rasW null cells. rasW null cells showed a larger, more spread-out morphology and reduced cell motility compared to wild-type cells. There was no significant difference between wild-type cells and rasW null cells during multicellular developmental process. These results suggest that RasW is involved in regulating cell morphology and cell migration in Dictyostelium.

• Journal of English Language & Literature
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• v.56 no.6
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• pp.1163-1190
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• 2010

Korean EFL learners' stylistic sensitivity was examined through the two types of letter writing, professional and personal. The base of comparison with the English native speakers' stylistic sensitivity was the linguistic style markers that were statistically found by Biber's (1988) multi-dimensional model of variation of English language. The main finding was that Korean university students were sensitive to stylistic difference in the correct direction, though their linguistic repertoire was limited to the easy and simple linguistic features. Also, the learners were skewed in the involved style in both types of the letters unlike the native speakers and it was interpreted as due to the general developmental direction from informal to formal linguistic style. Learners were also skewed in the explicit style in both types of letters unlike the native speakers and it was interpreted as due to the learners' heavy reliance on one particular linguistic feature. As a whole, the learners' stylistic sensitivity heavily relied on the small number of linguistic features that they have already acquired, which happen to be simple and basic linguistic features.

• The Journal of Korea Assosiation for Disability and Oral Health
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• v.10 no.2
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• pp.61-67
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• 2014

The aim of this study was to analyze the clinical characteristics of patients with cognitive and behavioral impairments receiving dental treatment under general anesthesia (GA-dental treatment). From August 2007 to April 2014, information was collected from 475 patients who received GA-dental treatment at the Clinic for Persons with Disabilities, Seoul National University Dental Hospital. The demographic factors (gender, age, disability, medication, GA history, residency type, caregiver, meal type, oral hygiene maintenance, and cooperation level) and dental status (operating duration, DMFT, malocclusion, periodontal disease, tooth defect, and treatment protocol) of the patients were evaluated. DMFT and malocclusion levels were compared among the patients with ANOVA and Sheffe's post-hoc test, and chi-square test, respectively. The correlation between the demographic characteristics and dental status of the patients were analyzed with the Pearson's correction test. The mean age of the patients was 27.1 (7 - 83) years and they had intellectual disabilities (55.4%), developmental disorders (17.9%), brain disorders (16.6%), neurocognitive disorders (4.6%), or others (5.5%). The mean DMFT (DT) was 8.6 (5.2) with a significant difference among the disability types (p<0.05). The incidence of malocclusion was higher in patients with intellectual disabilities and brain disorders than in the other types (p<0.05). The operation time ($191.4{\pm}91.2min$) was correlated with decayed or endodontically-treated teeth (p<0.05). Special needs patients requiring GA-dental treatment showed unfavorable oral conditions. Dental practitioners experience time restrictions and additional costs under a GA setting. Treatment planning and decision-making can be efficiently facilitated by evaluating the clinical characteristics of the patients.

• Korean Journal of Animal Reproduction
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• v.21 no.4
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• pp.373-379
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• 1997

This study was carried out to determine the hormone treatment scheme for an efficient superovulation and optimal recovery time for obtaining pronuclear embryos suitable for DNA injection in Korean native goats. For a superovulation, FSH(5.6mg) was given over four days in twice daily injections with (FSH/hCG group) or without(FSH group) hCG(100 IU) co-injection at the time of 7th FSH injection. Estrus cycle was synchronized by norgestomet ear-implantation for 11 days and its removal at the time of 6th FSH injection. Among the treated goats, the percentage of ovulated goats, which were examined at 70 to 76 h following implant removal, was greater in FSH/hCG group than in FSH group (100% vs 36.4%) but there was no significant difference in the mean numbers of ovulation points and fertilization rates between the two groups. To optimize hCG treatment scheme and recovery time, we injected hCG at the time of 7th (FSH/hCGa) or 8th(FSH/hCGb) FSH injection and then examined the developmental stage of the embryos recovered at different times after implant removal. In FSH/hCGa group, significant portions(31 to 44%) were beyond 1-cell stage, which was non-injectable, irrespective of their recovery time. However, in FSH/hCGb group recovered at 70 to 76 h after implant removal, great portions(69%) were fertilized and most of them(96.6%) were injectable 1-cell stage. Considering together the fertilization rate and developmental stage of recovered embryos, it is recommendable to administrate hCG at the time of final 8th FSH injection and collect the embryos at 70 to 76 h after implant removal to obtain injectable embryos as many as possible in Korean native goats.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.63-63
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• 2003

In an effort to uncover the spermatogenic impairment by the polychlorinated biphenyls (PCBs), the expression of tight junctions (TJs) genes important for the formation of the blood testis barrier (BTB) were examined following the 3,3',4,4',5-pentachloro biphenyl (PCB126) treatment in cultured neonatal testis in mice. At 4 days (D4) after 10 and 100 nM PCB126 treatment the expression of claudin-11 was significantly increased when compared with vehicle control. In contrast no difference in occludin and claudin-1 expression was found among the experimental group. On D8, 100 nM PCB126 significantly increased the expression of claudin-11 but not occludin and claudin-1. 1 uM PCB126 treatment significantly decreased expressions of occludin and ciaudin -1, suggesting the general toxic effect on the Sertoli cell. Because PCB126 does not alter the proliferative activity of spermatogenic cells and Sertoli cells in neonatal testis, it is likely that increase in the expression of claudin-11 by low dose of PCB126 may attribute to the alteration of the Sertoli cells differentiation in testis. It also emphasized that PCB126 might have differentially affected the transcription of TJ genes in Sertoli cells. In conclusion, this result suggests that the structure of TJ may be targeted by PCB126 in neonatal testis in mice and that co-PCB is potentially harmful to spermatogenesis by alteration of the development of BTB.

• Journal of Korean Public Health Nursing
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• v.26 no.3
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• pp.453-464
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• 2012

Purpose: The purpose of this study was to provide the basic data for university students to develop program for achieving successful developmental task. Method: The subjects involved this study were 462 1-4th grade university students located at Kangwon-Do & Chungchung-Do. Data were measured using Global assessment of recent stress scale, CES-D and Self-esteem scale. Data were analyzed using SPSS WIN 17.0 program that included mean, standard deviation, ANOVA, Sheffe test and Pearson correlation coefficients. Results: 1) The mean score of the degree of perceived stress was 4.17(${\pm}1.43$), depression was .92(${\pm}.47$), and self esteem was 2.89(${\pm}.48$). 2) There were significant differences in the degree of stress according to gender(t=2.03, p=.043), level of living(F=3.55, p=.029). Likewise, there were significant differences in the degree of depression according to gender(t=3.35, p=.001), age(t=2.15, p=.032), level of living(F=3.38, p=.035) and in the degree of self-esteem there were significant difference according to gender(t=3.64, p<.001), age(t=2.81, p=.005), participation of regular meeting or not(t=3.14, p=.002), frequency of alcohol drinking(F=5.59, p=.004), onset age of alcohol drinking(t=2.43, p=.016). 4) There was a significant relationship between stress and depression(r=.556, p<.001), self-esteem (r=-.423, p<.001). Also, there was a significant relationship between depression and self esteem(r=-.667, p<.001). Conclusions: Nursing interventions and educational programs which can help the students to accomplish the developmental tasks required.

• Korean Journal of Environmental Biology
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• v.29 no.4
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• pp.379-387
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• 2011

Copepod nauplii plays an important role as a linker between the microbial food web and classical food chain in marine ecosystem and is an essential food source for early stage of many larval fishes. Study on the influencing factors on the growth of copepod naupliar stages has been rarely carried out in despite of these ecological significances. Many studies have shown that food availability and temperature are major factors to influence copepod growth. However, due to the complicated environment parameters in coastal ecosystem, the relationships between growth of copepods and influencing factors are still unclear under the natural condition. Growth rates of the copepod $Acartia$ $hongi$ nauplii were measured in Kyeonggi Bay from February to December 2001. $Acartia$ $hongi$ is numerically abundant and widespread predominant species in the coastal regions of the Yellow Sea and occurs continuously throughout the year, with a maximum peak in late spring. The naupliar growth rates of $Acartia$ $hongi$ by the artificial cohort method varied from 0.03 to 0.18 $day^{-1}$, with a mean of 0.09 $day^{-1}$. The overall naupliar growth rates showed a significantly positive relationship with the variation in water temperature. However, Previous study reported that the growth rates of adult $Acartia$ $hongi$ were primarily influenced by the variation in chlorophyll-$a$. Therefore, these differences demonstrated that the influencing factors of growth did not correspond with the developmental stages. The results of this study suggest that the dissimilarity of growth between nauplius and adult female resulted from the size-dependant difference in food availability and the growth of older developmental stages containing adults are more food-dependent than juveniles.

• Development and Reproduction
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• v.21 no.3
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• pp.237-247
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• 2017

Mammalian spermatogenesis occurs in a precise and coordinated manner in the seminiferous tubules. One of the attempts to understand the detailed biological process during mammalian spermatogenesis at the molecular level has been to identify the testis specific genes followed by study of the testicular expression pattern of the genes. From the subtracted cDNA library of rat testis prepared using representational difference analysis (RDA) method, a complimentary DNA clone encoding type III member of a DnaJ family protein, DnaJC18, was cloned (GenBank Accession No. DQ158861). The full-length DnaJC18 cDNA has the longest open reading frame of 357 amino acids. Tissue and developmental Northern blot analysis revealed that the DnaJC18 gene was expressed specifically in testis and began to express from postnatal week 4 testis, respectively. In situ hybridization studies showed that DnaJC18 mRNA was expressed only during the maturation stages of late pachytene, round and elongated spermatids of adult rat testis. Western blot analysis with DnaJC18 antibody revealed that 41.2 kDa DnaJC18 protein was detected only in adult testis. Immunohistochemistry study further confirmed that DnaJC18 protein, was expressed in developing germ cells and the result was in concert with the in situ hybridization result. Confocal microscopy with GFP tagged DnaJC18 protein revealed that it was localized in the cytoplasm of cells. Taken together, these results suggested that testis specific DnaJC18, a member of the type III DnaJ protein family, might play a role during germ cell maturation in adult rat testis.

• Journal of Embryo Transfer
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• v.26 no.3
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• pp.171-180
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• 2011

In this study I report that in vitro development rates of bovine nuclear transfer embryos activated either with boar sperm cytosolic factor (SCF) or with ionomycin followed by cycloheximide (CHX) and subsequent in vivo developmental rates after embryo transfer are related to blastocyst quality as evaluated by apoptosis analysis. SCF was extracted from porcine semen then purified for post-activation injection after nuclear transfer. The optimal timing for SCF injection was determined to be at least 22 h post-IVM for parthenogenetic activation of bovine oocyies. A total of 364 oocytes were successfully enucleated and 268 (73.6%) fused and were injected with SCF. The survival rate of fused and injected embryos was 109/113 (96.5%) after 2 h. The cleavage rates of nuclear transfer embryos after 3 d of culture in the ionomycin/CHX treated group were significantly higher than those of the SCF-activated group (93.3% vs 81.7%, p<0.01, respectively). However, at 7 d and 9 d there was no significant difference between the total developmental rates to blastocyst for either treatment group. Total blastocyst cell numbers were also not significantly different between the two activation treatments (ionomycin/CHX: 149.5${\pm}$7.7 vs. SCF: 139.3${\pm}$4.4 cells). In contrast, the apoptotic levels in the SCF blastocysts were higher than those produced after the chemical treatment (28.2${\pm}$5.1% vs. 8.8${\pm}$0.6%, respectively). A total of 18 expanded or hatching blastocysts was transferred to nine synchronized recipients in each activation group; 5/9 (55.5%) and 2/9 (22.2%) were pregnant at 40 d in the ionomycin/CHX treatment and SCF activated group, respectively. However, only one went to term in the ionomycin/CHX treatment while none of the pregnancies from the SCF group were maintained by 90 d. In conclusion, these results suggest that SCF derived from different species is a limited activator to be used for activation after bovine nuclear transfer in lieu of a chemical activation protocol.

• The Journal of Korean Physical Therapy
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• v.28 no.4
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• pp.232-242
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• 2016

Purpose: This study was conducted to develop a Korean version of the pediatric functional muscle test (K-PFMT) for children with motor developmental disorders, and to verify its reliability and validity. Methods: The subjects were 40 children, aged below 5 years. Each was scored on the K-PFMT by 14 physical therapists to determine inter-rater reliability and internal consistency. Additionally, 3 of the 14 therapists tested 20 children again one or two weeks later to determine test-retest reliability. The internal consistency was calculated by Cronbach's alpha. The inter-rater and test-retest reliability were calculated using the intraclass correlation coefficient (ICC). One-way ANOVA and the paired t-test were used to compare differences among the three evaluator groups and between the test and retest group. Concurrent validity was evaluated by Pearson's correlation with a total score of GMFM. Results: Chronbach's alpha was over 0.98 for each test item and 0.99 for the total items. There was no significant differences in the score of K-PFMT among the three evaluator groups except for a few items. The test-retest ICC was from 0.89 to 1.00 and from 0.82 to 1.00, respectively. There was no significant difference between the test and retest group, except for a few items. There were high significant correlations between K-PFMT and GMFM. Conclusion: This study showed that a K-PFMT with relatively high reliability and validity was successfully developed. The K-PFMT will be a useful tool for measurement of muscle strength of children with motor developmental disorder.