• Journal of the Korea Institute of Military Science and Technology
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• v.10 no.3
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• pp.5-15
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• 2007

A welding structures is generally composed of dissimilar steel materials in order to reduce weight cost, and has a gap to fill the welding agent. Also, heat flow analysis should be fulfilled for structure existing of gap to figure out residual stress which is generated after welding. Since mechanical properties of welding structure composed of dissimilar steel is more fragile than mechanical properties of welding structure consisted of same material, heat flow analysis verifying this should be fulfilled as well. Therefore, on this research, heat flow analysis about dissimilar steel weldment consisted of gap existing AISI304 and AISI630 is practiced so that it could be a basic data of research about mechanical properties of gap existing dissimilar steel welding part which is going to be studied later on. During heat flow analysis, heat input model which based on Gaussian profile and using volume heat flux was newly consisted and applied. In addition, for verifying of analysis on this research, gap existing dissimilar steel weldment which had gap of 0.25mm and was welded using Nd-YAG. The welding profile and temperature distribution for weldment during welding was compared to the result which was gotten through heat flow analysis. Both of those results corresponded each other.

• Korean Journal of Pharmacognosy
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• v.48 no.2
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• pp.134-140
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• 2017

In a series of investigations to develop a potential anti-obese agent, we prepared a immature Citrus fruits (IMF) and compared its lipid excretion effects to those of Citrus fruits (MF, CP, JP) in an ICR mouse model of obesity induced by a high fat diet. The body weights of IMF fed mice were found to be significantly lower from 2 weeks oral administration, despite the fact that their food intakes were similar to that of the HFD control mice. The fecal cholesterol content showed a significant increase in IMF (52.0 mg/g) at 7 weeks oral administration, and mature Citrus fruits (MF, 41.3 mg/g), immature Citrus peel (CP, 32.2 mg/g), mature Citrus peel (JP, 30.0 mg/g) respectively. And also, the triglyceride content in the feces showed a significant increase in MF (14.6 mg/g), and IMF (14.2 mg/g), CP (10.5 mg/g) and JP (10.0 mg/g), respectively. On the other hand, in the inhibition activity of pancreatic lipase, MF (0.78 nmol/min/ml) showed the greatest decrease in glycerol, CP (0.79 nmol/min/ml), JP, (0.93 nmol/min/ml) and IMF (1.42 nmol/min/ml).

• ALGAE
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• v.28 no.2
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• pp.131-147
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• 2013

Major progress has been made in the past decade towards understanding of the biosynthesis of red carotenoid astaxanthin and its roles in stress response while exploiting microalgae-based astaxanthin as a potent antioxidant for human health and as a coloring agent for aquaculture applications. In this review, astaxanthin-producing green microalgae are briefly summarized with Haematococcus pluvialis and Chlorella zofingiensis recognized to be the most popular astaxanthin-producers. Two distinct pathways for astaxanthin synthesis along with associated cellular, physiological, and biochemical changes are elucidated using H. pluvialis and C. zofingiensis as the model systems. Interactions between astaxanthin biosynthesis and photosynthesis, fatty acid biosynthesis and enzymatic defense systems are described in the context of multiple lines of defense mechanisms working in concert against photooxidative stress. Major pros and cons of mass cultivation of H. pluvialis and C. zofingiensis in phototrophic, heterotrophic, and mixotrophic culture modes are analyzed. Recent progress in genetic engineering of plants and microalgae for astaxanthin production is presented. Future advancement in microalgal astaxanthin research will depend largely on genome sequencing of H. pluvialis and C. zofingiensis and genetic toolbox development. Continuous effort along the heterotrophic-phototrophic culture mode could lead to major expansion of the microalgal astaxanthin industry.

• Journal of Physiology & Pathology in Korean Medicine
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• v.31 no.5
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• pp.270-276
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• 2017

The aim of this study was to investigate the effects of the water extract of Albizziae Cortex (AC) on the learning and memory impairments. AC was administered to normal mouse and scopolamine-injected amnesia mouse model. Passive avoidance test, Y-maze test, and Morris water maze test were conducted to confirm the cognitive-enhancing activities of AC. Acetylcholinesterase (AChE) activity and acetylcholine (Ach) content were measured after oral administration of AC. On the passive avoidance test, AC (200 mg/kg) significantly increased latency time and recovered scopolamine-impaired learning and memory in mice. In addition, AC (200 mg/kg) reduced Exploration time in target quadrant and reversed the scopolamine-induced cognitive impairments in the Y-maze test. Moreover, AC (200 mg/kg) increased exploration time in target quadrant and improved scopolamine-reduced escape latencies in the Morris water maze test. These effects were presented by regulatory effects of AC on AChE activity and Ach content. Taken together, AC increases cognitive-enhancing activities and ameliorates scopolamine-induced learning and memory impairment. AC might be a potential agent for prevention and treatment of amnesia and dementia.

• Toxicological Research
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• v.30 no.4
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• pp.283-289
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• 2014

Tea flavonoids and polyphenols are well known for their extraordinary antioxidant activity which is considered important for anti-aging processes in animals. This study evaluated the anti-wrinkle effects of three different kinds of tea (Camellia sinensis) water extracts (CSWEs) including green, white, and black teas using a photoaged hairless mouse model. Data showed that the CSWE-treatment greatly improved skin conditions of mice suffering from UVB-induced photoaging, based on the parameters including the skin erythema index, moisture capacity, and transepidermal water loss. In addition, the wrinkle measurement and image analysis of skin replicas indicated that CSWEs remarkably inhibited wrinkle formation. In histological examination, the CSWE-treated mice exhibited diminished epidermal thickness and increased collagen and elastic fiber content, key signatures for skin restoration. Furthermore, the reduced expression of MMP-3, a collagen-degradative enzyme, was observed in the skin of CSWE-treated animals. Interestingly, comparative data between green, white, and black tea indicated that the anti-wrinkle activity of white tea and black tea is equally greater than that of green tea. Taken together, these data clearly demonstrated that CSWEs could be used as an effective anti-wrinkle agent in photoaged animal skin, implying their extended uses in therapeutics.

• Korean Journal of Plant Tissue Culture
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• v.27 no.3
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• pp.239-243
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• 2000

Helicobacter pylori, an etiologic agent of gastritis and peptic ulceration, produces urease which elicits a powerful immunoglobulin response in H. pylori-infected individuals. To establish a model plant vaccine agains H. pylori, 750 bp -ureA DNA amplified by polymerase chain reaction from pH 808 plasmid harboring urease gene cluster was cloned and manipulated to be expressed in tobacco plants. From the regenerated transgenic tobacco plants, ureA DNA integration,m its mRNA expression and protein synthesis were analyzed and confirmed by standard molecular techniques. The CaMV 35S promoter-driving ureA construct was expressed to produce a 30 kDa protein which was identical with bacterial UreA in size when detected on immunoblot of SDS polyacrylamide gel electrophoresis.

• Archives of Pharmacal Research
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• v.25 no.4
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• pp.550-555
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• 2002

The discovery and development of the taxane class of antitumor compounds represent significant advances in the treatment of patients with a variety of malignancies. These drugs are effectively used in the treatment of breast cancer. In this study we evaluated the efficacy of fractionated usage of both paclitaxel and docetaxel as a single agent in the breast cancer cell line MCF-7. It has been shown that the cytotoxic effect of paclitaxel was increased when the divided $IC_{50}$ concentrations were used sequentially and in contrast to paclitaxel, cytotoxic effect of docetaxel was decreased with the same schema and the single dose of $IC_{50}$ concentration was optimal. The cause of the difference between the cytotoxic effects of two agents with this schedule is obscure. Demonstrating mechanisms, which are responsible for these differences, will be important for more rational use of taxoids and to provide basis for the following clinical trials.

• Archives of Pharmacal Research
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• v.20 no.6
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• pp.539-544
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• 1997

Anti-metastatic activities of IH901, an intestinal bacterial metabolic derivative formed from Ginseng protopanaxadiol saponins, was determined in vitro and in vivo. Under in vitro conditions, IH901 inhibited the migration of bovine aortic endothelial cells 25 times stronger than suramin and suppressed the invasion of HT1080 human fibrosarcoma cells into reconstituted basement membrane components of Matrigel 1000 times stronger than RGDS peptide. IH901 also showed inhibitory effect on type-IV collagenase secretion from HT 1080 cells and platelet aggregation. When the anti-metastatic activity of IH901 was evaluated in comparison with that of 5-FU using a spontaneous lung metastatic model of Lewis lung carcinoma, the administration of IH901 (10 mg/kg p. o.) to tumor-bearing mice led to a significant decrease in lung metastasis (43% of untreated control), which was slightly more effective than that obtained with 5-FU (56% of control). Thus, IH901 seems to exhibit its anti-metastatic activity partly through the inhibition of tumor invasion which results from the blockade of type IV collagenase secretion and also through anti-platelet and anti-angiogenic activities.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.10a
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• pp.866-870
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• 2009

Mobile Health (M-Health) system is a recent term for medical and public health practice supported by mobile devices, such as mobile phones, PDAs, and other wireless devices. Mobile Health system has been successfully establishing at few general hospital in Korea. However, to use diverse devices manufactured by various company cause inoperability, and lack of security disappoints customers often. Although the outstanding health environment, most of hospitals are unavailable to share electronic patient records due to lack of standard protocol to handle the interoperability each other. Health Level 7 (HL7) is the best solution for the problem. In this paper, we will analyse a current M-Health service in terms of security and mobile device, and suggest iPhone for the best device against hospital environment. Also, for keep confidentiality of health information and patient privacy, enhanced security mechanism is introduced. As a consequence, interoperable standard, and most appropriate device for supporting staffs and M-Health performance, and enhanced securirty mechanism will be integrated in order to propose improved M-health model.

• Animal cells and systems
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• v.4 no.4
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• pp.381-388
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• 2000

Using a murine T cell hybridoma, activation-induced cell death (AICD) was studied. As an in vitro model system for the AICD, 1 cell hybridoma expressing TCR/CD3 complex was incubated onto the immobilized purified anti-CD3 antibody. The immobilized anti-CD3 antibody induced AICD effectively up to 40%. At 1-100 $\mu$M range of SNP, an exogenous source of nitric oxide (NO), the cell proliferation was not affected, but at 1 mM SNP, cell proliferation was significantly reduced. The AICD of T cell hybridoma was inhibited by exogenous NO at non-cytotoxic concentration, In the cells undergoing AICD, the expressions of caspase-3 and FasL were detected, but not iNOS. Similar result was recognized in the apoptosis induced by dexamethasone, an apoptosis-inducing agent. However, the conversion from the inactive form of caspase-3 (32 kDa) to the active form (17 kDa) was significantly reduced in the cells in AICD induced by anti-CD3 antibody, With the result of increased PARP cleavage in the cells, we propose that another PARP cleavage pathway not involving caspase-3 may function in the anti-CD3 antibody induced AICD in the T cell hybridoma.