• Reproductive and Developmental Biology
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• v.36 no.1
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• pp.33-37
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• 2012

Differential capacity of the parthenogenetic embryonic stem cells (PESCs) is still under controversy and the mechanisms of its neural induction are yet poorly understood. Here we demonstrated neural lineage induction of PESCs by addition of insulin-like growth factor-2 (Igf2), which is an important factor for embryo organ development and a paternally expressed imprinting gene. Murine PESCs were aggregated to embryoid bodies (EBs) by suspension culture under the leukemia inhibitory factor-free condition for 4 days. To test the effect of exogenous Igf2, 30 ng/ml of Igf2 was supplemented to EBs induction medium. Then neural induction was carried out with serum-free medium containing insulin, transferrin, selenium, and fibronectin complex (ITSFn) for 12 days. Normal murine embryonic stem cells derived from fertilized embryos (ESCs) were used as the control group. Neural potential of differentiated PESCs and ESCs were analyzed by immunofluorescent labeling and real-time PCR assay (Nestin, neural progenitor marker; Tuj1, neuronal cell marker; GFAP, glial cell marker). The differentiated cells from both ESC and PESC showed heterogeneous population of Nestin, Tuj1, and GFAP positive cells. In terms of the level of gene expression, PESC showed 4 times higher level of GFAP expression than ESCs. After exposure to Igf2, the expression level of GFAP decreased both in derivatives of PESCs and ESCs. Interestingly, the expression level of $Tuj1$ increased only in ESCs, not in PESCs. The results show that IGF2 is a positive effector for suppressing over-expressed glial differentiation during neural induction of PESCs and for promoting neuronal differentiation of ESCs, while exogenous Igf2 could not accelerate the neuronal differentiation of PESCs. Although exogenous Igf2 promotes neuronal differentiation of normal ESCs, expression of endogenous $Igf2$ may be critical for initiating neuronal differentiation of pluripotent stem cells. The findings may contribute to understanding of the relationship between imprinting mechanism and neural differentiation and its application to neural tissue repair in the future.

• Journal of Digital Convergence
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• v.11 no.10
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• pp.17-29
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• 2013

The major aim of this research is to examine the effect of computer and internet literacy and cellular phone possession on depression and suicidal ideation among elderly. This study used data of 2011 national survey results on the elderly life conditions. To determine the effectiveness of computer and internet literacy and cellular phone possession, a total of 6,774 respondents over 60 years of age was selected. The SPSS package was used to analyze the data. Multiple linear regression and logit analysis was run to verify influence of information conditions(computer and internet literacy and cellular phone possession) on depression and suicidal ideation. The results are as follows. First, the elder who is male, younger, has higher education and economic level and lives with spouce is in good information conditions. On the contrary to this, the elder who is female, older, low level of education and economic, single and lives with grandchildren is in information minority group. They have high level of depression and rate of suicidal ideation. Second, computer and internet literacy and cellular phone possession associate with level of depression significantly. Third, computer and internet literacy do not associate with suicidal ideation significantly. The results of this study provide significant source to plan informatization policy and welfare services for socially isolated older people.

• Journal of Korean Home Economics Education Association
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• v.20 no.3
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• pp.163-177
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• 2008

The purpose of this study is to see relationship between middle school students' cellular phone consumption behavior and their mothers' consumer education. A survey was conducted with middle school students at nine middle schools in Gyeongnam who possessed a cellular phone and their mothers(1,080 in total). The results of this study are as follows: First, middle school students' cellular phone consumption behavior was relatively at the average level or higher: they were best at A/S and change and refund and were at the average level in collecting and using information for purchase followed by contract. This consumption behavior was associated with such variables as gender, academic performance, and monthly pocket money. Second, as for consumer education for middle school students' mothers in general, purchase education was most highly recognized, followed by citizenship education and value education. However, value education was relatively weak, which should be reinforced. Mothers' consumer education was associated with children's grade, academic performance and monthly pocket money. Third, since middle school students' desirable cellular phone consumption behavior was strongly associated with their mothers' consumer education, it is highly urgent to improve the quality of consumer education by mothers at home.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.5
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• pp.33-47
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• 2015

Cellular Network assisted device-to-device (D2D) communication has been growing to reduce the overload of eNodeB and mitigate the frequency shortage. However, by sharing the uplink frequency resource with the cellular network, the interference between cellular and D2D is increased. In this paper, we propose an advanced receiver for full suppression cancellation (FSC) to reduce the interference between cellular and D2D. The proposed receiver can suppress and cancel the interference by integrating the interference rejection combining (IRC) technique with successive interference cancellation (SIC). We perform a system level simulation based on the 20-MHz bandwidth of the 3GPP LTE-A system. Simulation results show that the proposed receiver can improve SINR, throughput and spectral efficiency compared to conventional receivers.

• Journal of Korean Society of Transportation
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• v.18 no.4
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• pp.31-39
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• 2000

Cellular Phone use while driving is one of the critical causes of traffic accident by falling the driver into the improper lookout and inattention situations by disturbing the driving behaviors and by increasing the driver's mental workloads. These days, therefore, governments in many countries are trying to Prohibit the cellular Phone use while driving by the law focused on the hand-held type of cellular phone. This Paper investigated the impacts on the hands-free cellular Phone use while driving to the drivers Performance among normal and two different level of secondary task driving conditions in the urban of Japan. As the results, quantitative differences of drivers eye movement, subjective mental workload, steering wheel angle entropy, and cognitive Performance of secondary tasks were compared between straight and curve (right turn) section for each driving condition.

• The Journal of Advanced Prosthodontics
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• v.3 no.2
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• pp.63-68
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• 2011

PURPOSE. The object of this study was to investigate the effect of UV irradiation (by a general commercial UV sterilizer) on anodized titanium surface. Surface characteristics and cellular responses were compared between anodized titanium discs and UV irradiated anodized titanium discs. MATERIALS AND METHODS. Titanium discs were anodized and divided into the following groups: Group 1, anodized (control), and Goup 2, anodized and UV irradiated for 24 hours. The surface characteristics including contact angle, roughness, phase of oxide layer, and chemical elemental composition were inspected. The osteoblast-like human osteogenic sarcoma (HOS) cells were cultured on control and test group discs. Initial cellular attachment, MTS-based cell proliferation assay, and ALP synthesis level were compared between the two groups for the evaluation of cellular response. RESULTS. After UV irradiation, the contact angle decreased significantly (P<.001). The surface roughness and phase of oxide layer did not show definite changes, but carbon showed a considerable decrease after UV irradiation. Initial cell attachment was increased in test group (P=.004). Cells cultured on test group samples proliferated more actively (P=.009 at day 2, 5, and 7) and the ALP synthesis also increased in cells cultured on the test group (P=.016 at day 3, P=.009 at day 7 and 14). CONCLUSION. UV irradiation induced enhanced wettability, and increased initial cellular responses of HOS cells on anodized titanium surface.

• Journal of Korean Society of Transportation
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• v.19 no.6
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• pp.219-227
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• 2001

In this study, the simulation was constructed using CA(Cellular Automata) rule to analyze the effect of incidents, which was verified using real-time VDS data and data collected on the field. The study analyzed the effect of incidents on highways by the simulation. The result appears to be statistically available with 5% of significance level. In order to analyze the effect of incident, the study classified time period of incidents and types of incidents in relation with traffic volume. Also, the effect of each type of incidents was analyzed in terms of time difference in sectional travel and delay time. In conclusion, little effect of incidents on traffic flow is noticed with light traffic volume but it becomes serious as the traffic volume increases. In addition, the delay happens to appear without incidents as the traffic volume increases over 2000 veh/hour. Also, when incidents happened during 45 minutes, the delay was about 425-722 veh·hour.

• Journal of dental hygiene science
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• v.23 no.4
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• pp.264-270
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• 2023

Background: Resin-based dental materials release residual monomers or other substances from incomplete polymerization into the oral cavity, thereby causing adverse biological effects on oral tissue. 10-Methacryloyloxydecyl dihydrogen phosphate (10-MDP), an acidic monomer containing dihydrogen phosphate and methacrylate groups, is the most commonly used component of resin-based dental materials, such as restorative composite resins, dentin adhesives, and resin cements. Although previous studies have reported the cytotoxicity and biocompatibility in various cultured cells, the effects of resin monomers on cellular aging have not been reported to date. Therefore, this study aimed to investigate the effects of the resin monomer 10-MDP on cellular senescence and inflamm-aging in vitro. Methods: After stimulation with 10-MDP, MC3T3-E1 osteoblast-like cells were examined for cell viability by WST-8 assay and reactive oxygen species (ROS) production by flow cytometry. The protein and mRNA levels of molecular markers of aging were determined by western blotting and RT-PCR analysis, respectively. Results: Treatment with 0.05 to 1 mM 10-MDP for 24 hours reduced the survival of MC3T3-E1 cells in a concentration-dependent manner. The intracellular ROS levels in the 10-MDP-treated experimental group were significantly higher than those in the control group. 10-MDP at a concentration of 0.1 mM increased p53, p16, and p21 protein levels. Additionally, an aging pattern was observed with blue staining due to intracellular senescence-associated beta-galactosidase activity. Treatment with 10-MDP increased the levels of tumor necrosis factor-α, interleukin (IL)-1β, IL-6 and IL-8, however their expression was decreased by mitogen-activated-protein-kinase (MAPK) inhibitors. Conclusion: Taken together, these results suggest that the exposure of osteoblast-like cells to the dental resin monomer 10-MDP, increases the level of cellular senescence and the inflammatory response is mediated by the MAPK pathway.

• Journal of Pharmacopuncture
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• v.22 no.4
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• pp.248-252
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• 2019

Objectives: The aim of the present work is evaluating the special effects of Urtica Dioica and Lamium Album on the serum level of K-Ras and GSK-3 beta in diabetic rats. Methods: In the present experimental study, 32 male Wistar rats randomly divided into 4 groups (Group I: normal control rats; receiving daily PBS, Group 2: diabetic control rats; receiving single dose of streptozotocin (60 mg/kg) and daily PBS, Group 3: Diabetic rats treated with 100 mg/kg of hydroalcoholic extract of the U. dioica, Group 4: Diabetic rats treated with 100 mg/kg of hydroalcoholic extract of L. Album. Diabetes-induced by an intraperitoneal injection of streptozotocin (60 mg/ kg). On the 14 th day of treatment, the weight, fasting blood sugar (FBS) and on 28 th day blood glucose, K-Ras and GSK3 beta was measured. Results: In diabetic group blood GSK- 3 beta increase in comparison to control group (P < 0.05), also blood K-Ras decrease in the diabetic group (P < 0.05). Both extracts reduced GSK-3 beta level, however, this reduction was only statistically significant by U.dioica (P < 0.05). Compared to diabetic group, blood K-Ras level increased by both extract (P < 0.05). Also diabetes induction increase blood glucose levels and both extracts decrease its level significantly (P < 0.05).there is no significant differences among both extract effects on blood glucose, and K-Ras. Conclusion: For the first time shown that both extracts by regulating GSK-3 beta and K-Ras improve blood glucose level. More studies are needed to determine all the effects of these herbs.

• Biomolecules & Therapeutics
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• v.13 no.4
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• pp.256-262
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• 2005

We examined the signaling molecules involved in the 6-hydroxydopamine (6-OHDA)-induced neuronal cell death and increase in cellular glutathione (GSH) level in SK-N-SH cells. The 6-OH-DA-induced cell death was significantly prevented by the pretreatment with N-acetylcysteine (NAC), a thiol antioxidant, and BAPTA, an intracellular $Ca^{2+}$ chelator. Although 6-OHDA induced ERK phosphorylation, the pretreatment with PD98059, an ERK inhibitor, did not block 6-OHDA-induced cell death. In addition, the 6-OHDA-induced activation of caspase-3, a key signal for apoptosis, was blocked by the pretreatment with NAC and BAPTA. While the level of reactive oxygen species (ROS) was significantly increased in the 6-OHDA-treated cells, the cellular GSH level was not altered for the first 6-hr exposure to 6-OHDA, but after then, the level was significantly increased, which was also blocked by the pretreatment with NAC and BAPTA, but not by PD98059. Depletion of GSH by pretreating the cells with DL-buthionine-(S,R)-sulfoximine (BSO), a glutathione synthesis inhibitor, rather significantly potentiated the 6-OHDA-induced death. In contrast to the pretreatment with NAC, 6-OHDA-induced cell death was not prevented by the post-treatment with NAC 30 min after 6-OHDA treatment. The results indicate that the GSH level which is increased adaptively by the 6-OHDA-induced ROS and intracellular $Ca^{2+}$ is not enough to overcome the death signal mediated through ROS-$Ca^{2+}$ -caspase pathway.