• Molecules and Cells
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• 제26권1호
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• pp.18-25
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• 2008

Arsenic trioxide (ATO) can affect many biological functions such as apoptosis and differentiation in various cells. We investigated the involvement of ROS and GSH in ATO-induced HeLa cell death using ROS scavengers, especially N-acetylcysteine (NAC). ATO increased intracellular ${O_2}^{{\cdot}-}$ levels and reduced intracellular GSH content. The ROS scavengers, Tempol, Tiron and Trimetazidine, did not significantly reduce levels of ROS or GSH depletion in ATO-treated HeLa cells. Nor did they reduce the apoptosis induced by ATO. In contrast, treatment with NAC reduced ROS levels and GSH depletion in the ATO-treated HeLa cells and prevented ATO-induced apoptosis. Treatment with exogenous SOD and catalase reduced the depletion of GSH content in ATO-treated cells. Catalase strongly protected the cells from ATO-induced apoptosis. In addition, treatment with SOD, catalase and NAC slightly inhibited the G1 phase accumulation induced by ATO. In conclusion, NAC protects HeLa cells from apoptosis induced by ATO by up-regulating intracellular GSH content and partially reducing the production of ${O_2}^{{\cdot}-}$.

• 대한약침학회지
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• 제20권4호
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• pp.257-264
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• 2017

Introduction: Pharmacopuncture, which combines acupuncture with herbal medicine, is one of the newly developed acupuncture techniques that has recently been put into use. The possible mechanisms of scolopendra pharmacopuncture, as well as its potential effects on depressive symptoms, were investigated in this study by using a mouse model of chronic immobilization stress (CIS). Methods: C57BL/6 male mice were randomly assigned into three groups: mice not stressed with restraint and injected with distilled water, mice stressed with restraint and injected with distilled water, and mice stressed with restraint injected with scolopendra pharmacopuncture at a cervical site. Behavioral tests (an open field test, tail suspension test, and forced swimming test) were carried out after two weeks of CIS and injection treatments. The expression levels of glial fibrillary acidic protein (GFAP) in the hippocampus were determined by using western blot and immunohistochemistry analyses. Results: Mice exposed to CIS showed decreased behavioral activity, while scolopendra pharmacopuncture treatment significantly protected against the depressive-like behaviors induced by CIS. Moreover, scolopendra pharmacopuncture treatment increased GFAP protein levels in the hippocampi of the mice stressed by chronic immobilization. Conclusion: Scolopendra pharmacopuncture has an ameliorating effect on depressive behavior, which is partially mediated through protection against glial loss in the hippocampus.

• 농촌의학ㆍ지역보건
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• 제22권1호
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• pp.61-74
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• 1997

In case of tissue invading nematode, proteolytic enzyme was required at their parasitic life. Proteinases obtained from these parasites(Toxocara canis, Ansakis spp. and Trichinella spiralis) were extracted, isolated and further purified. And then the analysis for activity and inhibitory effect of proteinases were performed by appropriate substrate. Determination of protein as a circulating antigen was done in use of infected animal serum with above parasites, respectively. For above experimental objects, following procedures were performed. First, enzymatic activity was measured in use of azocasein and inhibitory effect of porteinase were studied by various inhibitors. Second, partially purified proteins containing enzymatic activity were obtained by ion exchange chromatography, ultrafiltration and electrophoretic elution. Third, role of the partially purified protein as a circulating antigen. The results obtained were as follows : 1. Enzymatic activity of each nematode proteinase was varied according to pH. Optimal pH of Toxocara canis, Ansakis spp. and Trichinella spiralis were pH 6.0, pH 5.5 and pH 6.5, respectively. The optimal molarity of buffer was 0.1M phosphate buffer. Although little difference between these proteinases was observed, temperature stability was at least maintained at $4^{\circ}C$ until 5 days. 2. In case of Ansakis spp. and Toxocara canis, enzymatic activity of these proteinases was considerably inhibited by Leupeptin and EDTA. For maximum enzymatic activity of above proteinases, it was required that cysteine residue of enzyme should be protected. And it was suggested that metallo type was contained in enzyme active site. Proteinase of Trichinella spiralis contained metallo type also. 3. Although partial purification was performed in Ansakis spp. and Toxocara canis, proteins maintaining enzymatic activity were identified as a circulating antigen. From SDS-PAGE and immunoblot, 25 kDa was presented in Ansakis spp.. Specific antigen of Toxocara cains was 110 kDa protein fraction. 55 and 42 kDa proteins were reacted with normal serum. Trichinella spiralis 60 kDa protein fraction was successfully purified from excretory materials in culture. As a result of immune-reaction with Trichinella spiralis infected serum, highly purified 60 kDa protein was maintained antigenicity until final purification step.

• 한국재료학회지
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• 제25권4호
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• pp.196-201
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• 2015

This paper presents the impact of partial shading on $CuIn_xGa_{(1-x)}Se_2(CIGS)$ photovoltaic(PV) modules with bypass diodes. When the CIGS PV modules were partially shaded, the modules were under conditions of partial reverse bias. We investigated the characterization of the bypass diode and solar cell properties of the CIGS PV modules when these was partially shaded, comparing the results with those for a crystalline silicon module. In crystalline silicon modules, the bypass diode was operated at a partial shade modules of 1.67 % shading. This protected the crystalline silicon module from hot spot damage. In CIGS thin film modules, on the other hand, the bypass diode was not operated before 20 % shading. This caused damage because of hotspots, which occurred as wormlike defects in the CIGS thin film module. Moreover, the bypass diode adapted to the CIGS thin film module was operated fully at 60% shading, while the CIGS thin film module was not operated under these conditions. It is known that the bypass diode adapted to the CIGS thin film module operated more slowly than that of the crystalline silicon module; this bypass diode also failed to protect the module from damage. This was because of the reverse saturation current of the CIGS thin film, $1.99{\times}10^{-5}A/cm^2$, which was higher than that of crystalline silicon, $8.11{\times}10^{-7}A/cm^2$.

• 동의생리병리학회지
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• 제25권6호
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• pp.1014-1019
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• 2011

Curcumin is a natural phytochemical present in turmeric, the ground powder of the rhizomes of Curcuma longa. Curcumin has been described as having antioxidant, anti-inflammatory, and anti-carcinogenic properties. However, it is still largely unknown whether curcumin inhibits the UVB-induced inflammatory reaction in HaCaT keratinocyte cell lines. In this study, to confirm the photoprotection properties of curcumin, HaCaT keratinocyte cells were irradiated by UVB, and then treated with curcumin. UVB irradiation induced the increased expressions of IL-$1{\beta}$, TNF-${\alpha}$, IL-6, IL-8, and COX-2 in HaCaT cells. These increased expressions of cytokines (IL-$1{\beta}$, TNF-${\alpha}$, IL-6, IL-8, and COX-2) were down-regulated by curcumin treatment in UVB-irradiated HaCaT cells. In addition skin of hairless mice were damaged by UVB irradiation, which were evidenced by atrophy of epidermis and decrease of collagen in dermis. However, these damages were protected partially by co-treatment of curcumin. Taken together, this data indicate that curcumin may be a promising photoprotection agent, when used in massage pack or sunscreen product, to reduce cell death in UV-damaged skin.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제28권2호
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• pp.127-135
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• 2006

Objectives: The extent of bone formation that occurs at the interface of metallic implants and bone is determined by the number and activity of osteoblastic cells. Stress proteins may be contributing determinants of cell viability in altered environments. Hsp27 is a small Mr hsp which is known as a molecular chaperone. Methods: To better understand how heat shock protein 27 contributes to endosseous implant - associated metal ions affects on osteoblastic cell viability, the effect of chromium and titanium ions were compared to effects of cadmium ions in the ROS17/2.8 osteoblastic cell line. Results: ROS17/2.8 osteoblastic cell line demonstrated ion - specific reductions in growth; reductions were significantly greater for cadmium than for chromium or titanium. Chromium impaired growth of cultures without altering cell viability measured using the MTT assay. A stable transformed cell line expressing additional hsp27(clone "A7") was resistant to the toxic effects of titanium and partially protected from cadmium toxicity. Conclusions: A role for hsp27 in protection of osteoblastic cells from metal ion toxicity is supported by the chromium - induced elevations in hsp27 abundance and the behavior of the A7 cell line in response to metal ions in culture. Similar biochemical responses to altered cellular environments may contribute to the fate of tissues adjacent to select metallic implants.

• Composites Research
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• 제25권6호
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• pp.211-216
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• 2012

광섬유센서는 구조물에 매립 또는 부착시 전단응력에 의해 편광이 발생하여 피크가 2개로 갈라질 수 있기 때문에 센서는 보호되고 양 끝단을 고정하는 방법으로 패키징을 하여야 하나, 광섬유의 클래딩 부분을 부착하는 방식으로 고정하면, 변형발생시 광케이블을 구성하는 코어와 클래딩 사이에서 미끄러짐 현상이 발생하기 때문에 이를 방지하기위해 센서의 양 끝단에 고정구를 사용하고 광섬유를 부분탈피하여 부착하여 접점을 만들어 줌으로써 외력에 의해 발생하는 변형을 정확하게 측정이 가능하도록 하였다. 그리고 기존 광섬유격자센서가 자체적으로 압축변형의 측정이 곤란한 점을 개선하기위해 미리 긴장(Pre-Strain)상태를 유지하기 위하여 두 개의 접점사이를 볼트와 너트로 조절하여 프리스트레인 가변이 가능하도록 하여 인장/압축변형 측정을 가능하게 한 광섬유격자센서 패키지를 제작하였다. 이러한 광섬유격자센서패키지를 실제구조물에 적용하여 측정하였으며, 이를 통하여 안전을 감시하는 모니터링시스템에 적용할 수 있도록 하였다.

• 미생물학회지
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• 제16권2호
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• pp.47-61
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• 1978

Strptomyces albus T-12 which ahd been isolated and identified in the laboratory, was selected for the studies on the cultural conditions on the production of D-xylose iosmerase and the enzymological characteristics using the partially purified enzyme. The best results in the enzyme production came from D-xylose medium than wheat bran. The divalent metla ions as $Co^{2+},\;Fe^{2+},\;Zn^{2+}\;and\;Cu^{2+}$ retard or inhibit the cell-growth at the early stages of mycelia propagations, and T-12 strain is especially sensitive to $Co^{2+}$. After 60 hours of shaking cultivation at $30^{\circ}C$ and 200 rpm, a maximum enzyme activitz, 0.49 enzyme units, was obtained. Cell-free enzyme obtained from mycelia heat-treated in the prescence of 0.5mM $Co^{2+}$, showed a 2.4-fold increase in specific than the enzyme from untreated mycelia. The specific activity of the purified enzyme through Sephadex G-150 columm showed 180 fold to the crude enzyme. The effective activators of the enzyme appeared to be $Mg^{2+}\;and\;Co^{2+}$ ions, and it exhibited the maximal enzyme activity showed at pH 7.0 and at tempersture around $80^{\circ}C$ when $Mg^{2+}\;and\;Co^{2+}$ ions were added. The enzyme isomerized D-glucose, D-xylose, D-ribose, L-arabinose, D-mannose, and L-rhamnose in the present of $Mg^{2+}\;and\;Co^{2+}$ ions as an activatiors. $Mg^{2+}\;and\;Co^{2+}$ ions were non-competitively bound at different allosterix sites of enzyme molecule. $Mg^{2+}(5mM)\;or\;Co^{2+}(1.0mM)$ protected against the thermal denaturations of the enzyme activities. The michelis constant(Km) and $V_{max}$ values of the emzyme for D-glucose and D-xylose were 0.52M, $2.12{\mu}moles/ml{\cdot}min.\;and\;0.28M,\;0.65moles/ml{\cdot}min.$, respectively.

• Biomolecules & Therapeutics
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• 제20권3호
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• pp.306-312
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• 2012

Resveratrol (trans-3,5,4'-trihydroxystilbene) has received considerable attention recently for the potential neuroprotective effects in neurodegenerative disorders where heme oxygenase-1 (HO-1) and sirtuin 1 (SIRT1) represent promising therapeutic targets. Resveratrol has been known to increase HO-1 expression and SIRT1 activity. In this study, the effects of resveratrol and trans-3,5,4'-trimethoxystilbene (TMS), a resveratrol derivative, on cytotoxicity caused by glutamate-induced oxidative stress, HO-1 expression, and SIRT1 activation have been investigated by using murine hippocampal HT22 cells, which have been widely used as an in vitro model for investigating glutamate-induced neurotoxicity. Resveratrol protected HT22 neuronal cells from glutamate-induced cytotoxicity and increased HO-1 expression as well as SIRT1 activity in a concentration-dependent manner. Cytoprotection afforded by resveratrol was partially reversed by the specific inhibition of HO-1 expression by HO-1 small interfering RNA and the nonspecific blockage of HO-1 activity by tin protoporphyrin IX, but not by SIRT1 inhibitors. Surprisingly, TMS, a resveratrol derivative with methoxyl groups in lieu of the hydroxyl groups, and trans-stilbene, a non-hydroxylated analog, failed to protect HT22 cells from glutamate-induced cytotoxicity and to increase HO-1 expression and SIRT1 activity. Taken together, our findings suggest that the cytoprotective effect of resveratrol was at least in part associated with HO-1 expression but not with SIRT1 activation and, importantly, that the presence of hydroxyl groups on the benzene rings of resveratrol appears to be necessary for cytoprotection against glutamate-induced oxidative stress, HO-1 expression, and SIRT1 activation in HT22 neuronal cells.

• Bulletin of the Korean Chemical Society
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• 제34권7호
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• pp.2117-2124
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• 2013

The binding properties and sequence selectivities of ${\Delta}{\Delta}$- and ${\Lambda}{\Lambda}-[{\mu}-Ru_2(phen)_4(bip)]^{4+}$ (bip = 4,4'-biphenylene (imidazo [4,4-f][1,10]phenanthroline) complexes with $poly[d(A-T)_2]$ and $poly[d(G-C)_2]$ were investigated using conventional spectroscopic methods. When bound to $poly[d(A-T)_2]$, a large positive circular dichroism (CD) spectrum was induced in absorption region of the bridging moiety for both the ${\Delta}{\Delta}$- and ${\Lambda}{\Lambda}-[{\mu}-Ru_2(phen)_4(bip)]^{4+}$ complexes, which suggested that the bridging moiety sits in the minor groove of the polynucleotide. As luminescence intensity increased, decay times became longer and complexes were well-protected from the negatively charged iodide quencher compared to that in the absence of $poly[d(A-T)_2]$. These luminescence measurements indicated that Ru(II) enantiomers were in a less polar environment compared to that in water and supported by minor groove binding. An angle of $45^{\circ}$ between the molecular plane of the bridging moiety of the ${\Delta}{\Delta}-[{\mu}-Ru_2(phen)_4(bip)]^{4+}$ complex and the local DNA helix axis calculated from reduced linear dichroism ($LD^r$) spectrum further supported the minor groove binding mode. In the case of ${\Lambda}{\Lambda}-[{\mu}-Ru_2(phen)_4(bip)]^{4+}$ complex, this angle was $55^{\circ}$, suggesting a tilt of DNA stem near the binding site and bridging moiety sit in the minor groove of the $poly[d(A-T)_2]$. In contrast, neither ${\Delta}{\Delta}$-nor ${\Lambda}{\Lambda}-[{\mu}-Ru_2(phen)_4(bip)]^{4+}$ complex produced significant CD or $LD^r$ signal in the absorption region of the bridging moiety. Luminescence measurements revealed that both the ${\Delta}{\Delta}$- and ${\Lambda}{\Lambda}-[{\mu}-Ru_2(phen)_4(bip)]^{4+}$ complexes were partially accessible to the $I^-$ quencher. Furthermore, decay times became shorter when bis-Ru(II) complexes bound to $poly[d(G-C)_2]$. These observations suggest that both the ${\Delta}{\Delta}$- and ${\Lambda}{\Lambda}-[{\mu}-Ru_2(phen)_4(bip)]^{4+}$ complexes bind at the surface of $poly[d(G-C)_2]$, probably electrostatically to phosphate group. The results indicate that ${\Delta}{\Delta}$- and ${\Lambda}{\Lambda}-[{\mu}-Ru_2(phen)_4(bip)]^{4+}$ are able to discriminate between AT and GC base pairs.