• Title/Summary/Keyword: material degradation

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A Study on the Material Characteristics and Weathering Aspects of Sculpture Stone Around the World Cultural Heritage Joseon Dynasty Royal Tombs - Focused on the East Nine Royal Tombs - (세계문화유산 조선왕릉 석조문화재의 재질특성 및 풍화양상 연구 - 구리 동구릉을 중심으로 -)

  • CHO Hajin ;CHAE Seunga ;SONG Jinuk;LEE Myeongseong ;LEE Taejong
    • Korean Journal of Heritage: History & Science
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    • v.55 no.4
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    • pp.180-193
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    • 2022
  • The East Nine Royal Tombs is a representative place in the Royal Tombs of Joseon (a World Heritage Site). It consists of 1,289 stone artifacts including 979 related stone structures, 310 stone statues, and objects. Most of the stone structures in the East Nine Royal Tombs are composed of biotite granite, but some tombs are composed of light red granite. As a result of magnetic susceptibility measurement, the average data from Geonwolleung to Mongneung, excluding Hyeolleung, were similar, so it is estimated that stones were obtained from the same quarry. In the case of Sungneung, Sureung, and Gyeongneung, the range of susceptibility measurement is widely distributed. It assumed that the newly produced stones were mixed in the moving and construction process. Also, stones might be gathered from different quarries. As a result of a conservation status investigation, both the mound member and the ridge stone had the highest damage rate due to peeling and granular decomposition according to surface weathering. In the case of surface discoloration, yellowing and soils were found in the burial mound members. Yellowing, blackening, and soil were identified in the ridge stone structures. Bio-degradation is the major factor of deterioration of the East Nine Royal Tombs and the conservation status of the tombs were detected as grades 4 to 5. It seems that it is easy for the environment of the royal tombs to form soil for the microorganisms and fine conditions for continuous moisture. In the case of structures, they are in relatively good condition. As a result of a comprehensive damage rating for each tomb, the overall condition is good, but the Geonwolleung Royal Tomb and Hyeolleung Tomb, which were created in the early period, had relatively high weathering ratings. Stone objects in East Nine Royal Tombs have lost many pieces and gateway members due to surface deterioration. Also, secondary damage is ongoing. Each damage factor of the stone artifacts of the East Nine Royal Tombs combines to cause various and continuous damages. Therefore, it is necessary to establish regular conservation status data of the stone artifacts for efficient management after processing as well as conservation treatment of the royal tombs, and specific management manuals and systems. This study investigated the conservation status of stone structures in the East Nine Royal Tombs, a World Heritage Site, and systematically classified them to provide priority and necessity for conservation processing. We look forward to establishing a plan for the conservation and management of the East Nine Royal Tombs with this database in the future.

A Study on Preparation of 3'-$[^{18}F]$Fluoro-3'-deoxythymidine and Its Biodistribution in 9L Glioma Bearing Rats (3'-$[^{18}F]$Fluoro-3'-deoxythymidine의 합성과 9L glioma 세포를 이식한 래트에서의 체내동태에 관한 연구)

  • Shim, Ah-Young;Moon, Byung-Seok;Lee, Tae-Sup;Lee, Kyo-Chul;An, Gwang-Il;Yang, Seung-Dae;Yu, Kook-Hyun;Cheon, Gi-Jeong;Choi, Chang-Woon;Lim, Sang-Moo;Chun, Kwon-Soo
    • Nuclear Medicine and Molecular Imaging
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    • v.40 no.5
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    • pp.263-270
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    • 2006
  • Purpose: Several radioisotope-labeled thymidine derivatives such as $[^{11}C]$thymidine was developed to demonstrate cell proliferation in tumor. But it is difficult to track metabolism with $[^{11}C]$thymidine due to rapid in vivo degradation and its short physical half-life. 3'-$[^{18}F]$fluoro-3'-deoxythymidine ($[^{18}F]$FLT) was reported to have the longer half life of fluorine-18 and the lack of metabolic degradation in vivo. Here, we described the synthesis of the 3'-$[^{18}F]$fluoro-3'-deoxythymidine ($[^{18}F]$FLT) and compared with $([^{18}F]FET)\;and\;([^{18}F]FDG)$ in cultured 9L cell and obtained the biodistribution and PET image in 9L tumor hearing rats. Material and Methods: For the synthesis of $[^{18}F]$FLT, 3-N-tert-butoxycarbonyl-(5'-O-(4,4'-dimet hoxytriphenylmethyl)-2'-deoxy-3'-O-(4-nitrobenzenesulfonyl)-${\beta}$-D-threopentofuranosyl)thymine was used as a FLT precursor, on which the tert-butyloxycarbonyl group was introduced to protect N3-position and nitrobenzenesulfonyl group. Radiolabeling of nosyl substitued precursor with $^{18}F$ was performed in acetonitrile at $120^{\circ}C$ and deproteced with 0.5 N HCI. The cell uptake was measured in cultured 9L glioma cell. The biodistribution was evaluated in 9L tumor bearing rats after intravenous injection at 10 min, 30 min, 60 min and 120 min and obtained PET image 60 minutes after injection. Results: The radiochemical yield was about 20-30% and radiochemical purity was more than 95% after HPLC purification. Cellular uptake of $[^{18}F]$FLT was increased as time elapsed. At 120 min post-injection, the ratios of tumor/blood, tumor/muscle and tumor/brain were $1.61{\pm}0.34,\;1.70{\pm}0.30\;and\;9.33{\pm}2.22$, respectively. The 9L tumor was well visualized at 60 min post injection in PET image. Conclusion: The uptake of $[^{18}F]$FLT in tumor was higher than in normal brain and PET image of $[^{18}F]$FLT was acceptable. These results suggest the possibility of $[^{18}F]$FLT at an imaging agent for brain tumor.

Effects of Electrodeposition Parameters on Electrochemical Hydroxyl Radical Evolution of PbO2 Electrode (이산화납 전극 제조 시 전기화학적 증착인자가 수산화라디칼 발생에 미치는 영향)

  • Shim, Soojin;Yoon, Jeyong
    • Journal of Korean Society of Environmental Engineers
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    • v.38 no.12
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    • pp.647-655
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    • 2016
  • Lead dioxide ($PbO_2$) is an electrode material that is effective for organic pollutant degradation based on hydroxyl radical ($^{\bullet}OH$) attack. Representative parameters for $PbO_2$ electrodeposition are summarized to current, temperature, reaction time, concentration of Pb(II) and electrolyte agent. In this study, $Ti/PbO_2$ electrodes were fabricated by electrodeposition method under controlled reaction time, current density, temperature, concentration of $HNO_3$ electrolyte. Effects of deposition parameters on $^{\bullet}OH$ evolution were investigated in terms of electrochemical bleaching of p-Nitrosodimethylaniline (RNO). As major results, the $^{\bullet}OH$ evolution was promoted at the $PbO_2$ that was deposited in longer reaction time (1-90 min), lower current density ($0.5-50mA/cm^2$), higher temperature ($5-65^{\circ}C$) and lower $HNO_3$ concentration (0.01-1.0 M). Especially, the $PbO_2$ which was deposited in 0.01 M of lowest $HNO_3$ concentration by applying $20mA/cm^2$ for above 10 min was most effective on $^{\bullet}OH$ evolution. The performance gap between $PbO_2$s that was best and worst in $^{\bullet}OH$ evolution was about 41%. Among the properties of $PbO_2$ related on $^{\bullet}OH$ evolution performance, conductivity of $Ti/PbO_2$ significantly influenced on $^{\bullet}OH$ evolution. The increase in conductivity promoted $^{\bullet}OH$ evolution. In addition, the increase in crystal size of $PbO_2$ interfered $^{\bullet}OH$ evolution at surface of some $PbO_2$ deposits.

Transformation of Asbestos-Containing Slate Using Exothermic Reaction Catalysts and Heat Treatment (발열반응 촉매제와 열처리를 이용한 석면함유 슬레이트의 무해화 연구)

  • Yoon, Sungjun;Jeong, Hyeonyi;Park, Byungno;Kim, Yongun;Kim, Hyesu;Park, Jaebong;Roh, Yul
    • Economic and Environmental Geology
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    • v.52 no.6
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    • pp.627-635
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    • 2019
  • Cement-asbestos slate is the main asbestos containing material. It is a product made by combining 10~20% of asbestos and cement components. Man- and weathering-induced degradation of the cement-asbestos slates makes them a source of dispersion of asbestos fibres and represents a priority cause of concern. When the asbestos enters the human body, it causes cellular damage or deformation, and is not discharged well in vitro, and has been proven to cause diseases such as lung cancer, asbestos, malignant mesothelioma and pleural thickening. The International Agency for Research on Cancer (IARC) has designated asbestos as a group 1 carcinogen. Currently, most of these slats are disposed in a designated landfill, but the landfill capacity is approaching its limit, and there is a potential risk of exposure to the external environment even if it is land-filled. Therefore, this study aimed to exam the possibility of detoxification of asbestos-containing slate by using exothermic reaction and heat treatment. Cement-asbestos slate from the asbestos removal site was used for this experiment. Exothermic catalysts such as calcium chloride(CaCl2), magnesium chloride(MgCl2), sodium hydroxide(NaOH), sodium silicate(Na2SiO3), kaolin[Al2Si2O5(OH)4)], and talc[Mg3Si4O10(OH)2] were used. Six catalysts were applied to the cement-asbestos slate, respectively and then analyzed using TG-DTA. Based on the TG-DTA results, the heat treatment temperature for cement-asbestos slate transformation was determined at 750℃. XRD, SEM-EDS and TEM-EDS analyses were performed on the samples after the six catalysts applied to the slate and heat-treated at 750℃ for 2 hours. It was confirmed that chrysotile[Mg3Si2O5(OH5)] in the cement-asbestos slate was transformed into forsterite (Mg2SiO4) by catalysts and heat treatment. In addition, the change in the shape of minerals was observed by applying a physical force to the slate and the heat treated slate after coating catalysts. As a result, the chrysotile in the cement-asbestos slate maintained fibrous form, but the cement-asbestos slate after heat treatment of applying catalyst was broken into non-fibrous form. Therefore, this study shows the possibility to safely verify the complete transformation of asbestos minerals in this catalyst- and temperature-induced process.

The Cooperative Environmental Research in the Yellow Sea between Korea and China for the Establishment of Cooperative Management Plans on the Yellows Sea Conservation (황해 공동 관리시스템 기반 조성을 위한 한.중 황해환경공동조사)

  • Heo, Seung;An, Kyoung-Ho;Park, Soung-Yun;Park, Jong-Soo;Kang, Young-Shil;Shon, Jaek-Young;Kim, Pyoung-Joong;Kim, Hyung-Chul;Hwang, Woon-Ki;Lee, Seung-Min;Hwang, Hak-Jin;Choi, Yong-Suk;Ko, Byeong-Seol;Bang, Hyun-Woo
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.15 no.3
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    • pp.263-268
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    • 2009
  • The Yellow Sea is extremely important to the economy and to the health and well-being of surrounding countries, Korea and China. Recently, the Yellow Sea is under constantly increasing threat of degradation due to the increase of environmental pollution and over-fishing. The governments of Korea and China have been aware of the importance of the Yellow Sea and reached an Environmental Agreement between Korea and China at the governmental level(November, 1993) According to this environmental agreement the Yellow Sea Environmental Cooperative Research between Korea and China has been undertaken since 1997. The joint cruise had been conducted once a year at 33 stations in the 4 lines of the Yellow Sea where the 9 stations of the D line was newly added in the 7th cruise in 2003. The samples were analyzed by scientists of both countries at the WSFRI, Korea and the OEMNC of the SEPA, China in turn, the annual report has been published every year during 1998-2008. The scientific efforts to fix the cruise time in October and to extend research frequency, as twice a year, should be considered, and this requires the governmental supports such as research funds and other related administrational assistance on both sides. Finally, scientists should also pay a concentrated attention to standardize the analytical methods including quality control and to improve this Yellow Sea research as one of the most representative international projects in the Yellow Sea where sharing additional informations available, if exist of dumping sites and material content, and of the freshwater quality will be of great help to broaden the output of this joint research project.

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Studies on the Effects of Amylase Addition to Rice Extrusion on the Rheological Properties of the Extrudate for Weaning Food Base (압출조리를 이용한 쌀 이유식 제조에서 아밀라제 첨가가 물성변화에 미치는 효과)

  • Lee, Gang-Gweon;Kim, Ji-Yong;Lee, Cherl-Ho
    • Korean Journal of Food Science and Technology
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    • v.26 no.6
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    • pp.670-678
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    • 1994
  • The effects of amylase addition during extrusion cooking of rice on the physico-chemical properties of the extrudates were investigated in order to develop rice-based Korean style weaning food products. A laboratory-built single screw extruder was used, the enzymes used were Termamyl 120LS(amylase from Bacillus licheniformis, NOVO Co.), BAN 240L(amylase from Bacillus amylolichuefaciens, NOVO Co.) and malt powder. By the addition of enzymes, the water soluble index of the extrudates increased by 3 times compared to that of the extrudates without enzyme and the concentration of reducing sugar in the extrudates increased drastically at 28 feed moisture. The gel permeation chromatographic pattern showed that the large molecular starch fractions diminished by the addition of enzyme during extrusion and the low molecular fraction increased. The residual enzyme activity in the extrudate were 27% for the most thermo-resistance enzyme by treating at $140^{\circ}C$ in the metering section of the extruder. The sediment volume of the extrudate dispersion increased as the metering section temperature increased to $140^{\circ}C$ . By the addition of enzymes the viscosity of extrudate dispersion was redused $1/4{\sim}1/200$ of that of the extrudates without enzyme. It allowed to use 1.8 times of solid material to the weaning food formulation to attain the same level of consistency as the commercial products. It proves that the addition of amylase during rice extrusion is effective to increase the energy density of weaning food by starch degradation, which results in the increases of water solubility, reducing sugar content, dispersibility and fluidability.

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Rewetting Strategies for the Drained Tropical Peatlands in Indonesia (인도네시아의 배수된 열대 이탄지에 대한 재습지화 전략)

  • Roh, Yujin;Kim, Seongjun;Han, Seung Hyun;Lee, Jongyeol;Son, Yowhan
    • Korean Journal of Environmental Biology
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    • v.36 no.1
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    • pp.33-42
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    • 2018
  • The tropical peatlands have been deforested and converted to agricultural and plantation areas in Indonesia. To manage water levels and increase the overall productivity of crops, canals have been constructed in tropical peatlands. The canals destructed the structure of the tropical peatlands, and increased the subsidence and fire hazard risks in the region. The Indonesian government enacted regulations and a moratorium on tropical peatlands, in order to reduce degradation. A practical method under the regulations of rewetting tropical peatlands was to permit a canal blocking. In this study, four canal blocking projects were investigated regarding their planning, construction priority, design, building material, construction, monitoring, time and costs associated with the canal blockings. In the protected areas, regulations restricted the development of the tropical peatlands areas that were noted as deeper than 3 m, and the administration stopped issuing new concessions for future work projects for this noted criteria of land use. A noted purpose of canal blockings in these areas was to effectuate the restoration of the lands in the region. The main considerations of the restoration efforts were to maintain a durability of the blockings, and to encourage the participation of the area stakeholders. In the case of a concession area, regulations were set into place to restrict clear-cutting and shifting cultivation, and to maintain groundwater level in the tropical peatland. The most significant priorities identified in the canal blocking project were the efficiency and cost-effectiveness of the project. Nevertheless, the drainage of tropical peatlands has been continued. On the basis of a literature review on regulations and rewetting methods in tropical peatlands of Indonesia, we discussed the improvements of the regulations, and adequate canal blockings to serve the function to rewet the tropical peatlands in Indonesia. Our results would help establishing an adequate direction and recommended guideline on viable rewetting methods for the restoration of drained tropical peatlands in Southeast Asia.

Treatment Characteristics of Soil Clothing Contact Oxidation Process using Bio-media (생물담체를 충진한 토양피복 산화접촉공정의 하수처리특성)

  • Kim, Hong-Jae;Kang, Jae-Hee;Lee, Ki-Seok;Motoki, Kubo;Kang, Chang-Min;Chung, Seon-Yong
    • Journal of Korean Society of Environmental Engineers
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    • v.27 no.4
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    • pp.414-419
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    • 2005
  • This study was performed to compare the treatment efficiencies of two media, newly developed Bio-rock and conventional gravel, in soil clothing contact oxidation process. The composition of synthetic wastewater were $COD_{Cr}$ $150{\sim}370\;mg/L$, $BOD_5$ $150{\sim}270\;mg/L$, T-N $20{\sim}60\;mg/L$, T-P $5{\sim}25\;mg/L$, pH 7 and 2 mL/L of trace element solution. The experiment using two reactors was comparatively conducted for the flow rate of 40 L/d for 13 months, respectively. Initially Bio-rock reactor was increased to pH 12 due to $Ca(OH)_2$ with hydration of cement, but gravel reactor was dropped to pH 4 due to the degradation of organic material and nitrification. This significant pH variation deteriorated the growth and activity of microorganism. But the high pH of Bio-rock seems favorite to ammonia stripping and precipitation of phosphate. Such pH variation of Bio-rock and gravel reactors were finally stabilized to pH 8 and pH 6, respectively. The removal efficiencies of organic compounds from Bio-rock reactor were 96% of $COD_{Cr}$, 98% of $BOD_5$, 80% of T-N and 85% of T-P which stably coping against variation of influent concentration. But those of gravel reactor were 96% of $COD_{Cr}$, 96% of $BOD_5$, 42% of T-N and 40% of T-P, respectively. The Bio-rock was 2 times higher than T-N and T-P in treatment efficiency. And electron-microscopic examination showed that Bio-rock was more favorable to microbial adherence than gravel. The microbial populations were $5.2{\times}10^6\;CFU/mL$ of Bio-rock reactor compared to $2.6{\times}10^6\;CFU/mL$ in gravel reactor. In result Bio-rock was favor to microbial adherence and high treatment efficiency in spite of variation of influent concentration which had the advantages in saving running time and reducing site requirement.

The Relationship between Heme Oxygenase-1 Expression and Response to Cisplatin Containing Chemotherapy in Advanced Non-Small Cell Lung Cancer (진행성 비소세포폐암에서 Heme oxygenase-1 발현과 Cisplatin을 포함하는 항암화학요법의 치료반응과의 연관성)

  • Yang, Doo Kyung;Roh, Mee Sook;Lee, Kyung Eun;Kim, Ki Nam;Lee, Ki Nam;Choi, Pil Jo;Bang, Jung Hee;Kim, Bo Kyung;Seo, Hyo Rim;Kim, Min Ji;Kim, Seul Ki;Lee, Soo-Keol;Son, Choon Hee
    • Tuberculosis and Respiratory Diseases
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    • v.60 no.3
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    • pp.314-320
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    • 2006
  • Background : The overall response (20-30%) to chemotherapy in non-small cell lung cancer (NSCLC) is quite poor. Heme oxygenase-1 (HO-1) is the rate-limiting enzyme in heme degradation. There is increasing evidence suggesting that the induction of HO-1 might have an important protective effect against oxidative stress including cisplatin containing chemotherapy. This study retrospectively investigated the relationship between HO-1 expression and the response to chemotherapy containing cisplatinin advanced NSCLC patients. Material and Methods : The medical records including the responses to chemotherapy of fifty nine cases were evaluated retrospectively, and the tissue samples of these patients were immunohistochemically stained for HO-1. Results : Forty three of the fifty nine patients(72.8%) showed positive staining for HO-1 in their cancer tissues. There was no significant difference according to the cell type, stage and tumor size. In addition, there was no correlation between HO-1 expression and the responses to chemotherapy. Conclusion : HO-1 expression in tumor tissue dose not predict the response to cisplatin containing chemotherapy in advanced NSCLC. Further prospective studies with a larger number of patients will be needed to confirm these results.

The Role of Heme Oxygenase-1 in Lung Cancer Cells (폐암세포주에서 Heme Oxygenase-1의 역할)

  • Jung, Jong-Hoon;Kim, Hak-Ryul;Kim, Eun-Jung;Hwang, Ki-Eun;Kim, So-Young;Park, Jung-Hyun;Kim, Hwi-Jung;Yang, Sei-Hoon;Jeong, Eun-Taek
    • Tuberculosis and Respiratory Diseases
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    • v.60 no.3
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    • pp.304-313
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    • 2006
  • Background : Heme oxygenase-1 (HO-1) is an inducible enzyme that catalyzes the oxidative degradation of heme to form biliverdin, carbon monoxide (CO), and free iron. The current evidence has indicated a critical role of HO-1 in cytoprotection and also in other, more diverse biological functions. It is known that the high expression of HO-1 occurs in various tumors, and that HO-1 has an important role in rapid tumor growth because of its antioxidative and antiapoptotic effects. Therefore, the role of HO-1 was analyzed in human lung cancer cell lines, and especially in the A549 cell line. Material and Methods : Human lung cancer cell lines, i.e., A549, NCI-H23, NCI-H157 and NCI-H460, were used for this study. The expression of HO-1 in the untreated state was defined by Western blotting. ZnPP, which is the specific HO inhibitor we used, and the viability of cells were tested for by conducting MTT assaysy. The HO enzymatic activity, as determined via the bilirubin level, was also indirectly measured. Moreover, the generation of intracellular hydrogen peroxide (H2O2) was monitored fluorimetrically with using a scopoletin-horse radish peroxidase (HRP) assay and 2',7'-dichlorofluorescein diacetate (DCFH-DA). We have also transfected small HO-1 interfering RNA (siRNA) into A549 cells, and the apoptotic effects were evaluated by flow cytometric analysis and Western blotting. Results : The A549 cells had a greater expression of HO-1 than the other cell lines, whereas ZnPP significantly decreased the viability of the A549 cells more than the viability of the other lung cancer cells in a dose-dependant fashion. Consistent with the viability, the HO enzymatic activity also was decreased. Moreover, intracellular H2O2 generation via ZnPP was induced in a dose-dependent manner. Apoptotic events were, then induced in the HO-1 siRNA transfected A549 cells. Conclusion : HO-1 provides new important insights into the possible molecular mechanism of the antitumor therapy in lung cancer.