• BMB Reports
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• 제41권2호
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• pp.146-152
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• 2008

In the presence of NGF, PC12 cells extend neuronal processes, cease cell division, become electrically excitable, and undergo several biochemical changes that are detectable in developing sympathetic neurons. We investigated the expression pattern of the apoptosis-related genes at each stage of neuronal differentiation using a cDNA microarray containing 320 apoptosis-related rat genes. By comparing the expression patterns through time-series analysis, we identified candidate genes that appear to regulate neuronal differentiation. Among the candidate genes, HO2 was selected by real-time PCR and Western blot analysis. To identify the roles of selected genes in the stages of neuronal differentiation, transfection of HO2 siRNA in PC12 cells was performed. Down-regulation of HO2 expression causes a reduction in neuronal differentiation in PC12 cells. Our results suggest that the HO2 gene could be related to the regulation of neuronal differentiation levels.

• 대한기계학회논문집A
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• 제25권2호
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• pp.182-191
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• 2001

The paper describes the improvement on concurrent subspace optimization(CSSO) via automatic differentiation. CSSO is an efficient strategy to coupled multidisciplinary design optimization(MDO), wherein the original design problem is non-hierarchically decomposed into a set of smaller, more tractable subspaces. Key elements in CSSO are consisted of global sensitivity equation, subspace optimization, optimum sensitivity analysis, and coordination optimization problem that require frequent use of 1st order derivatives to obtain design sensitivity information. The current version of CSSO adopts automatic differentiation scheme to provide a robust sensitivity solution. Automatic differentiation has numerical effectiveness over finite difference schemes tat require the perturbed finite step size in design variable. ADIFOR(Automatic Differentiation In FORtran) is employed to evaluate sensitivities in the present work. The use of exact function derivatives facilitates to enhance the numerical accuracy during the iterative design process. The paper discusses how much the automatic differentiation based approach contributes design performance, compared with traditional all-in-one(non-decomposed) and finite difference based approaches.

• 대한가정학회지
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• 제49권5호
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• pp.97-115
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• 2011

The focus of this study was on the self-differentiation level of families with an elderly member suffering from dementia. Based on 340 questionnaires collected in Seoul and Gyeonggi, the study intended to explain the adaptation issues of those families. The variables of interest, which might be related to the self-differentiation, were chronic anxiety(i.e. stress), the family function, psychosomatic symptoms and the family's adaptation to care-giving. As a result of analyzing the effects of the variables potentially related to the self-differentiation level of care-giving families, the findings from this study were as follow. With decreasing self-differentiation level of the family caring for an elderly member suffering from dementia, the levels of stress and psychosomatic symptoms were significantly increased, but the family function and the adaptation to care-giving tended to decrease. Conversely, with increasing self-differentiation, the levels of stress and psychosomatic symptoms were significantly decreased, while the family function and adaptation to care-giving were promoted.

• Journal of Ginseng Research
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• 제35권1호
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• pp.45-51
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• 2011

Wild ginseng has been used as a traditional medicine for thousands of years and for increase physical strength in Korea, China and Japan. This study reports that cultivated wild ginseng (CWG) inhibits adipocyte differentiation of 3T3-L1 pre-adipocytes in a concentration-dependent manner. Inhibition of adipocyte differentiation is one possible anti-obesity strategy. CWG inhibits the expression of the adipocyte differentiation regulator peroxisome proliferators-activated receptor (PPAR)${\gamma}$ and CCAAT/enhancer-binding protein ${\alpha}$mRNA. It also inhibited the expression of PPAR${\gamma}$ and adiponectin at the protein level during the differentiation of pre-adipocytes into adipocytes. Additionally, CWG blocked the cell cycle at the sub-$G_1$ phase transition, causing cells to remain in the pre-adipocyte state. These results indicate that CWG inhibits adipocyte differentiation and adipogenesis through pre-adipocyte cell cycle arrest in cultured 3T3-L1 cells.

• 약학회지
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• 제55권4호
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• pp.309-313
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• 2011

Abnormal growth of adipocyte characterized by increased cell numbers and differentiation is considered as an major pathological characteristic feature in obesity. Thus, inhibition of mitogenesis of preadipocytes and their differentiation to adipocytes would be beneficial for the prevention and inhibition of obesity. In the present study, we attempted to evaluate anti-adipogenic activity of eggplants (the fruits of Solanum melongena L.) employing preadipocytes cell line, 3T3-L1 as an in vitro assay system. Water extract of eggplants significantly inhibited adipocyte differentiation when treated during adipocyte differentiation process, as assessed by measuring fat accumulation using Oil Red O staining. Eggplant extract, however, showed little effects on fully differentiated adipocytes. Eggplant didn't show significant toxicity up to 500 ${\mu}g$/ml to the 3T3-L1 cells. Further studies with interval treatment demonstrated that eggplant exerted inhibitory activity on adipocyte differentiation via acting on early stage of adipogenesis. Conclusively, eggplants are suggested to be beneficial for the prevention of obesity.

• 한방비만학회지
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• 제15권1호
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• pp.38-44
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• 2015

Objective: Skeletal muscle is a crucial tissue from the perspectives of mitochondrial dysfunction and insulin resistance, it is formed by myogenesis which is dynamic multistep process to be myotubes. The authors could found that root of Atractylodes macrocephala Koidzumi (Atractylodis Rhizoma Alba, ARA) enhanced glucose and lipid metabolism in C2C12 myotubes via mitochondrial regulation. However its action in myogenesis process is not known. The aim of this work was the study of ARA on proliferation, differentiation and hypertrophy in C2C12 cells. Methods: To study proliferation phase, cells were incubated in growth medium with or without ARA (0.2 or 1.0 mg/ml) for 24 hours. To examine differentiation, at 70% confluence, cells were transferred in differentiation medium both with/without ARA (0.2 or 1.0 mg/ml) for 96 hours. And after 72 hours of differentiation, cells were treated with or without ARA (0.2 or 1.0 mg/ml) for 24 hours, the genesis of hypertrophy in myotubes were analyzed. Results: In proliferation phase, ARA could make difference in morphologic examination. In differentiation phase, it also made morphologic difference furthermore ARA (1.0 mg/ml) increased mRNA expressions of Myogenic regulatory factors and muscle-specific proteins synthesis. In late differentiation, ARA induced hypertrophic morphological changes in neo-formed myotubes. Conclusions: ARA might control cell cycle promoting myogenesis and hypertrophy in C2C12 cells.

• 원예과학기술지
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• 제33권1호
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• pp.31-38
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• 2015

This study was carried out to investigate the relationship between endogenous polyamines (PAs) and floral bud differentiation in chrysanthemum (Chrysanthemum morifolium). In this study, PA content (free, bound, and conjugated) in apical buds, leaves, and roots changed appreciably during floral bud differentiation. PAs accumulated during series of processes such as floral induction, differentiation of floret primordia, and crown formation in apical buds; changes in PAs in apical buds may have a relationship with those in leaves and roots. The levels of free PAs and conjugated PAs [putrescine (Put) and spermine (Spm)] in apical buds rapidly increased during the initiation stage of floral bud differentiation, while free and conjugated spermidine (Spd) reached their highest levels at the stage of floret primordium differentiation. In the free, conjugated, and bound PA fractions, the changes in Spm content were negligible compared to those of Put and Spd throughout the experiment. These findings indicate that PAs participate in regulating the process of flower bud differentiation in chrysanthemum.

• 농업생명과학연구
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• 제45권2호
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• pp.85-92
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• 2011

The current study was conducted to investigate effects of sera taken from Hanwoo at different age on adipocyte differentiation. Sera were taken from Korean native (Hanwoo) steers at 6, 12, 18, and 24 months of age, respectively and supplemented to 3T3-L1 preadipocytes after the cells reached confluence and maintained 10 days thereafter. For the first 2 days (48 h), cells were induced to differentiate by addition of differentiation factors, methylisobutylxanthine, daxamethasone, and insulin. After the differentiation, the cells were incubated without differentiation factors except insulin. The cells lost their fibroblastic shape and showed round-up appearances after 10 days incubation with FBS and the sera of Hanwoo steers. Big lipid droplets appeared in the cells cultured with FBS and the sera taken from Hanwoo at 18 and 24 months of age. After 18 months of age, GPDH activity was statistically higher than 6 and/or 12 months of age (P < 0.05). Based on morphology and Sn-glycerol-3-phosphate dehydrogenase activities, Hanwoo steers expressed aged-dependent adipogenic activities, indicating that aged sera may result in high adipocyte differentiation. It is concluded that the 18 months of age may be 'threshold' to express major adipogenic activities. This may strongly support previous field studies reporting considerable increase in fat contents of Hanwoo carcass at over 18 months of age.

• 대한물리의학회지
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• 제14권2호
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• pp.63-70
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• 2019

PURPOSE: While electrical stimulation (ES) is known to be a safe and flexible tool in rehabilitation therapy, it has had limited adoption in muscle regeneration. This study was performed to investigate whether ES can induce myogenic differentiation and to clarify the mechanism underlying the effects of ES on myogenic differentiation. METHODS: This study used rat L6 cell lines as myoblasts for myogenic differentiation. Electric stimulation was applied to the cells using a C-Pace EP culture pacer (IonOptix, Westwood, Ma, USA). The gene expressions of myogenic markers were examined using qPCR and immunochemistry. RESULTS: Our study showed that ES increased the thickness and length of myotubes during myogenic differentiation. It was found that ES increased the expression of myogenic markers, such as MyoD and Myogenin, and also activated the fusion of the myoblast cells. In addition, ES suppressed the expression of small GTPases, which can explain why ES promotes myogenic differentiation. CONCLUSION: We found that ES induced myogenic differentiation by suppressing small GTPases, inhibiting cell division. We suggest that ES-based therapies can contribute to the development of safe and efficient muscle regeneration.

• Animal Bioscience
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• 제34권4호
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• pp.533-538
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• 2021

Objective: Pluripotent stem cell-derived lymphatic endothelial cells (LECs) show great promise in their therapeutic application in the field of regenerative medicine related to lymphatic vessels. We tested the approach of forced differentiation of mouse embryonal stem cells into LECs using biodegradable poly lactic-co-glycolic acid (PLGA) nanospheres in conjugation with growth factors (vascular endothelial growth factors [VEGF-A and VEGF-C]). Methods: We evaluated the practical use of heparin-conjugated PLGA nanoparticles (molecular weight ~15,000) in conjugation with VEGF-A/C, embryoid body (EB) formation, and LEC differentiation using immunofluorescence staining followed by quantification and quantitative real-time polymerase chain reaction analysis. Results: We showed that formation and differentiation of EB with VEGF-A/C-conjugated PLGA nanospheres, compared to direct supplementation of VEGF-A/C to the EB differentiation media, greatly improved yield of LYVE1(+) LECs. Our analyses revealed that the enhanced potential of LEC differentiation using VEGF-A/C-conjugated PLGA nanospheres was mediated by elevation of expression of the genes that are important for lymphatic vessel formation. Conclusion: Together, we not only established an improved protocol for LEC differentiation using PLGA nanospheres but also provided a platform technology for the mechanistic study of LEC development in mammals.