• Biomolecules & Therapeutics
• /
• v.13 no.4
• /
• pp.207-213
• /
• 2005

It has been proposed that reactive oxygen species (ROS), mainly superoxide anion ($O_2^-$) and hydrogen peroxide ($H_2O_2$), may mediate oxidative stress. Production of $H_2O_2$ during oxidative phosphorylation, inflammation, and ischemia can cause oxidative stress leading to cell death. Although glucose oxidase (GOX) in the presence of glucose continuously generates $H_2O_2$, it is not clear whether GOX produces apoptotic cell death in C6 glial cells. Thus, we investigated the mechanism by which GOX induces cell death. Cells were incubated with different concentration of GOX in the presence of glucose where cell viability, TUNEL and DNA ladder were analyzed. Results indicated that GOX exhibited cytotoxicity in a dose dependent manner by MTT assay. TUNEL positive cell and DNA laddering showed that GOX-induced cytotoxicity was due to apoptosis. Western blot analysis also showed that the cleaved caspase-3 level was detected in the GOX-treated cells at 10 mU/ml and increased dramatically at 30 mU/ml. Cleaved PARP also appeared at 10 mU/ml and lasted at 20 or 30 mU/ml of GOX. Cytochrome c level was increased by GOX dose dependently, which was contrast to Bcl-2 expression level. These results suggest that GOX induces apoptosis through caspase-3 activation, which followed by cytochrome c release from mitochondria through regulating of Bcl-2 level.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.15 no.4
• /
• pp.839-844
• /
• 2011

IPTV contents are based on MPEG2-TS(Moving Picture Expert Group-2 Transport Stream). The Created content is delivered to each home's Set-Top box through the Internet service network, which will be visible on television through the decoding process. The using and spending of content expanding were quite limited in the other existing lines' devices. For this end, provided methods are to convert MPEG2-TS to other format and then transmit it. These methods are causing not only an overload to the system but also its increasing the hardware resource requirements. In this paper, the MPEG2-TS of IPTV's content using RTP(Real time Transport Protocol) provided by the applicable variety of devices and environmental system, was designed and implemented. Through this paper, the existing MPEG2-TS is providing other devices for distribution and consumption that can give better content to the consumers which means that the QoS(Quality of Service) was enhanced. And, the increased consumption and use of content will help the IPTV business to get more development and activation.

• Environmental Analysis Health and Toxicology
• /
• v.20 no.4 s.51
• /
• pp.365-374
• /
• 2005

Ambient air particulate matters are classified into two distinct modes in sire distribution, namely the coarse and fine particles. Correlation between high particulate concentration and adverse effect on human populations has long been recognized. However, the toxicology of these adverse efforts has not been clarified. We investigated the genotoxic effect of PM 2.5 collected from urban area in Seoul by comet assay (A549 cells), CBMN assay (CHO-K1 cells) and EROD-microbioassay (H4IIE cells). Results from in vitro micronucleus assay and comet assay showed that PM 2.5 samples collected from traffic area, residential area and indoor air induced chromosomal damage and DNA breakage in a non-cytotoxic dose. The complex mixture effect of these PM 2.5 extracts was quantified by EROD-microbioassay in terms of its bio-TEQ (biologiral -TCDD equivalent concentration) which was 70.87$\pm$28.07, 93.55$\pm$21.80 and 14.31 $\pm$ 1.10 ng/g-PM 2.5 in traffic area, residental area and indoor air samples, respectively. Conclusively, we suggested that PM 2.5 collected from traffic area and residential area contains CYPIA inducer and genotoxic materials.

• The Korean Journal of Physiology and Pharmacology
• /
• v.9 no.5
• /
• pp.283-289
• /
• 2005

Endothelium, particularly pulmonary endothelium, is predisposed to injury by reactive oxygen species (ROS) and their derivatives. Heme oxygenase (HO) has been demonstrated to provide cytoprotective effects in models of oxidant-induced cellular and tissue injuries. In the present study, we investigated the effects of YS 49 against oxidant [tert-butylhydroperoxide (TBH)]-induced injury using cultured sheep pulmonary artery endothelial cells (SPAECs). The viability of SPAECs was determined by quantifying reduction of a fluorogenic indicator Alamar blue. We found that TBH decreased cell viability in a timeand concentration-dependent manner. YS 49 concentration- and time-dependently increased HO-1 induction on SPAECs. As expected, YS 49 significantly decreased the TBH-induced cellular injury. In the presence of zinc protophorphyrin, HO-1 inhibitor, effect of YS 49 was significantly inhibited, indicating that HO-1 plays a protective role for YS 49. Furthermore, YS 49 showed free radical scavenging activity as evidenced by 1,1-diphenyl-2-picrylhydrazyl (DPPH) and inhibition of lipid peroxidation. However, YS 49 did not inhibit apoptosis induced by lipopolysaccharide (LPS) in SPAECs. Taken together, HO-1 induction along with strong antioxidant action of YS 49 may be responsible for inhibition of TBH-induced injury in SPAECs.

• The Korean Journal of Physiology and Pharmacology
• /
• v.3 no.4
• /
• pp.375-382
• /
• 1999

Growing evidence indicates that enhanced generation or actions of nitric oxide (NO) are implicated in the pathogenesis of hypertension in spontaneously hypertensive rats and diabetic nephropathy in streptozotocin (STZ)-induced diabetic rats. We investigated whether inducible nitric oxide synthase (iNOS) expression in STZ-induced diabetic rats is responsible for the alterations of vascular reactivity. Diabetic state was confirmed 28 days after injection of STZ (i.p) in rats by measuring blood glucose. In order to evaluate whether short term (4 weeks) diabetic state is related with altered vascular reactivity caused by iNOS expression, isometric tension experiments were performed. In addition, plasma nitrite/nitrate (NOx) levels and expression of iNOS in the lung and aorta of control and STZ-treated rats were compared by using Griess reagent and Western analysis, respectively. Results indicated that STZ-treated rats increased the maximal contractile response of the aorta to phenylephrine (PE), and high $K^+,$ while the sensitivity remained unaltered. Endothelium-dependent relaxation, but not SNP-mediated relaxation, was reduced in STZ-treated rats. Plasma nitrite/nitrates are significantly increased in STZ-treated rats compared to controls. The malondialdehyde (MDA) contents of liver, serum, and aorta of diabetic rats were also significantly increased. Furthermore, nitrotyrosine, a specific foot print of peroxynitrite, was significantly increased in endothelial cells and smooth muscle layers in STZ-induced diabetic aorta. Taken together, the present findings indicate that enhanced release of NO by iNOS along with increased lipid peroxidation in diabetic conditions may be responsible, at least in part, for the augmented contractility, possibly through the modification of endothelial integrity or ecNOS activity of endothelium in STZ-diabetic rat aorta.

• The Korean Journal of Physiology and Pharmacology
• /
• v.4 no.4
• /
• pp.325-331
• /
• 2000

Tumor necrosis $factor-{\alpha}\;(TNF-{\alpha})$ plays important roles in inflammatory responses. Some of tetrahydroisoquinoline (THI) compounds exhibited to inhibit iNOS expression in animal studies and RAW 264.7 cells, but the action of THI on inflammatory reaction was not fully investigated. In the present study, we examined a limited series of THIs (higenamine, YS-51 and THI-52) on the $TNF-{\alpha}$ mRNA expression in mouse peritoneal macrophages by Northern analysis. When thioglycollate-stimulated peritoneal macrophages were incubated with LPS (100 ng/ml), expression of $TNF-{\alpha}$ mRNA was evident and reached its maximum at 2.5 h, which was reduced concentration-dependently by treatment with THIs. When the $TNF-{\alpha}$ activity of macrophage-conditioned media was measured using a TNF-sensitive L929 fibroblast cell line, CCL 1, all THIs increased the cell viability in a concentration dependent manner. The concentrations of THIs used are not cytotoxic by itself when analysed by MTT. Furthermore, nitrite/nitrate level was significantly reduced by the presence of THIs in cells treated with $LPS+interferon-{\gamma}\;(IFN-{\gamma}).$ It is concluded, thus, that these results strongly indicated that THIs can suppress the $TNF-{\alpha}$ expression and reduce NO, which may be useful for the inflammatory disorders.

• Convergence Security Journal
• /
• v.7 no.1
• /
• pp.19-27
• /
• 2007

Detecting unknown threats is a paradox ; how do you detect a threat if it is not known to exist? The answer is that unknown threat detection is the process of making a previously unknown threat identifiable in the shortest possible time frame. This paper examines the possibility of creating an unknown threat detection mechanism that security experts can use for developing a flexible protection system for networks. A system that allows the detection of unknown threats through monitoring system and the incorporation of dynamic and flexible logics with situational knowledge is described as well as the mechanisms used to develop such a system is illustrated. The system not only allows the detection of new threats but does so in a fast and efficient manner to increase the available time for responding to these threats.

• Journal of the Korea Convergence Society
• /
• v.10 no.12
• /
• pp.71-80
• /
• 2019

DevOps is a combining which means giving a diverse environments for software development and operations through whole software lifecycle. The key value of the proposed DevOps platform is the fast and stable service capability for a software development and operation environment. To do this, the DevOps gives pre-embedded 7 programming languages-Java, C/C++, Python, PHP, Ruby, Node.js, goLang and 7 service frameworks - Korea eGov Framework, Spring, Struts, Django, Laravel, Rails, Express. With the DevOps platform, it is possible to develop a software and also to build and distribute operation packages directly with the Linux containers. In this paper, the performance evaluation for a compile time, a distribution time and a processing capability is will be also proved. Though the performance evaluation, this paper shows capabilities of the proposed DevOps for Cloud services with commercial service level, prospectively.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.23 no.1
• /
• pp.14-20
• /
• 2003

Piezoelectric ultrasonic transducers for high temperature contact measurement were developed. These high temperature ultrasonic transducers (HTUT) consisted of bismuth titanate piezoceramic element whose Curie temperature is higher than $600^{\circ}C$, a backing material of the mixture of tungsten powder and inorganic binder, an inner alumina tube, a wear Plate and a housing. The operational frequencies or the HTUT were 1.04 and 2.08 MHz, respectively. Various commercially available couplants for high temperature were evaluated and compared. As a couplant for high temperature ultrasonic testing between HTUT and test specimen, gold epoxy was selected. The peak amplitude of pulse-echo signals from steel test specimen decreased with increasing temperature. The operational temperature of the HTUT reached up to $500^{\circ}C$ at which the continuous contact measurement was possible.

• Food Science of Animal Resources
• /
• v.37 no.6
• /
• pp.917-925
• /
• 2017

Whey protein, a by-product of milk curdling, exhibits diverse biological activities and is used as a dietary supplement. However, its effects on stress-induced vascular aging have not yet been elucidated. In this study, we found that whey protein significantly inhibited the Ang II-primed premature senescence of vascular smooth muscle cells (VSMCs). In addition, we observed a marked dose- and time-dependent increase in SIRT1 promoter activity and mRNA in VSMCs exposed to whey protein, accompanied by elevated SIRT1 protein expression. Ang II-mediated repression of SIRT1 level was dose-dependently reversed in VSMCs treated with whey protein, suggesting that SIRT1 is involved in preventing senescence in response to this treatment. Furthermore, resveratrol, a well-defined activator of SIRT1, potentiated the effects of whey protein on Ang II-primed premature senescence, whereas sirtinol, an inhibitor of SIRT1, exerted the opposite. Taken together, these results indicated that whey protein-mediated upregulation of SIRT1 exerts an anti-senescence effect, and can thus ameliorate Ang II-induced vascular aging as a dietary supplement.