• Journal of Periodontal and Implant Science
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• 제43권2호
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• pp.72-78
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• 2013

Purpose: The purpose of this study was to compare the phototoxic effects of blue light exposure on periodontal pathogens in both planktonic and biofilm cultures. Methods: Strains of Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, and Porphyromonas gingivalis, in planktonic or biofilm states, were exposed to visible light at wavelengths of 400.520 nm. A quartz-tungsten-halogen lamp at a power density of $500mW/cm^2$ was used for the light source. Each sample was exposed to 15, 30, 60, 90, or 120 seconds of each bacterial strain in the planktonic or biofilm state. Confocal scanning laser microscopy (CSLM) was used to observe the distribution of live/dead bacterial cells in biofilms. After light exposure, the bacterial killing rates were calculated from colony forming unit (CFU) counts. Results: CLSM images that were obtained from biofilms showed a mixture of dead and live bacterial cells extending to a depth of $30-45{\mu}m$. Obvious differences in the live-to-dead bacterial cell ratio were found in P. gingivalis biofilm according to light exposure time. In the planktonic state, almost all bacteria were killed with 60 seconds of light exposure to F. nucleatum (99.1%) and with 15 seconds to P. gingivalis (100%). In the biofilm state, however, only the CFU of P. gingivalis demonstrated a decreasing tendency with increasing light exposure time, and there was a lower efficacy of phototoxicity to P. gingivalis as biofilm than in the planktonic state. Conclusions: Blue light exposure using a dental halogen curing unit is effective in reducing periodontal pathogens in the planktonic state. It is recommended that an adjunctive exogenous photosensitizer be used and that pathogens be exposed to visible light for clinical antimicrobial periodontal therapy.

• 한국간호교육학회지
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• 제7권2호
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• pp.196-206
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• 2001

The purpose of this study was to identify Korean adolescents' sexual harassment conditions and patterns in schools as well as their psychological reactions when they are under sexual harassments or they committed sexual harassments. The subjects were 475 middle and high schoolers in Pusan and Gyeong Sang Nam-Do. The survey was executed from July 1 through Dec. 31, 2000. The collected data was analyzed by SPSS WIN 8.0 using percentage, mean. The results of this study were as follows: 1. the linguistic sexual harassment such as 'lewd jokes or dirty talks' was the major pattern(35.4%), The body touching such as 'kiss or embracing', 'internet transmission of pornography', 'sexual harassing of body characteristics', touching breast', 'grasping of hands or body touching', 'body touching in secret place', 'urging to sit in touch or on knees', 'exposing of special body areas', and 'showing pornography' followed in a row. 2. The eighteen point three percents of subjects had the experience to commit sexual harassment. The forty four point seven percent of above subjects committed it against their classmates. The first time to commit sexual harassment was their middle school period (38.4%). Their motives to commit it were as under: 'killing time'(48.8%), 'annoying', 'attracting attention from the other sex', 'expressing lovely emotions', 'urging of their friends', 'misunderstanding that the other partners felt good when they experienced sexual harassment, 'showing their strength' etc. their with committing harassments they felt as under ; 'joyful'(61.6%), 'funny,' 'desirous to try again', 'thrilling', 'breaking stress', very pleasant', 'exciting', 'regretful', 'guilty', and 'feeling fear' etc. 3. Twenty four point two percents of the population exposed to sexual harassments. The sexual harassers were almost their classmates (42.7%). And then unknown people', 'boy or girl friends and school staffs' followed in a row. The places where harassments happened were 'inside classroom'(69.8%), 'school bus and subway', 'outside school', etc. The feelings when experienced harassments were 'anger' (51.3%), 'hurting self-respect', 'embarrassing', 'rejection', 'insulting', 'shame', 'fear', 'dislike', 'anxiety', 'melancholy' etc. The reasons not to have consultations after sexual harassments were 'worrying to be well-known'(49.6%), 'believing not helpful enough', 'regarding simple mischief', 'trying to revenge directly', 'understanding their mistakes', 'worrying retaliation' etc.

• Journal of Chest Surgery
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• 제36권11호
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• pp.852-857
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• 2003

배경: 중피종은 일반적 치료에 대하여 큰 효과가 없다고 알려져 있다. 저자들은 Adenoviral p53에 민감하게 반응하는 중피종 세포주인 염증 및 표피세포 아유형(subtype)에 adenovirus유전자 핵산전달감염(transfection)으로 중피종 치료의 새로운 방법에 대하여 평가하고자 하였다. 대상 및 방법: 두 쌍의 adenoviral PTEN와 LacZ (Ad/GT-LacZ와 Ad/GV16) 매개체(vectors)에 REN (p53 sensitive)인 중피종 세포주(methothelioma cell lines)의 형질을 도입(transduction)하였으며, 단백질 함량은 Western blotting 분석을 이용하여 측정하였다. 세포사멸은 fluorescence-activated cell sorter analysis of subdiploid populations에 의하여 평가하였으며, 세포 생존력은 XTT 분석에 의하여 결정하였다. 통계 분석은 analysis of variance와 Student t test를 이용하여 하였다. 결과: Adenoviral PTEN 유전자로 처치된 세포사는 72시간 후에 MOI of 20에서 대조군 2.5%에 비하여 REN군 32.9%로 상대적으로 높게 나타났다. 또한 REN cell에서의 전구세포사멸 단백질(proapoptotic protein)인 BAX 발현 증가를, BCL-2에서 발현 감소를 나타내었으나, BCL-XL, BAK 및 BAD 단백질은 변화가 없었다. 결론: Adenovirus PTEN을 매개로 한 BAX 발현 증가는 세포사멸을 유도하고 p53에 민감한 중피종 세포들(p53-sensitive methothelioma cells)에서 세포 생존력을 감소시킨다. 이러한 결과는 PTEN 유전자 핵산전달감염하는 것은 중피종 치료의 새로운 대안적 방법이 될 수 있다는 것을 암시한다.

• 한국수산과학회지
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• 제33권4호
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• pp.331-338
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• 2000

최근 남해안 적조의 주요 원인생물인 C. polykrikoides를 살조 시키는 해양세균을 마산만의 적조발생 해역에서 분리, 동정하고 살조범위를 조사하였다. 분리 균주 중 살조활성이 우수한 Micrococcus sp. LG-5의 성장 특성과 살조효과에 대해 조사하여 해양 미생물을 이용한 자연생태 조화형, 환경 친화적 적조방제 기술 개발의 기초 자료를 제공하고자 연구한 결과를 요약하면 다음과 같다. 살조세균 Micrococcus sp. LG-5의 최적 성장조건은 $25^{\circ}C, NaCl 3.0{\%}, pH 7.0$이었으며, C. polykrikoides ($1.2{\times}10^4 cells/ml$)에 대한 Micrococcus sp. LG-5의 성장단계에 따른 배양여과액의 살조활성은 대수증식기 후기 및 정지기에 강하였다 대수증식기에는 C. polyklikoides를 $100{\%}$, 정지기에는 $82{\~}92{\%}$, 대수증식기 중기에는 $40{\~}80{\%}$, 유도기에는 $5{\%}$ 이하의 살조활성을 보여 Micrococcus sp. LG-5는 유도기를 거쳐 대수증식기에 살조물질을 활발히 생산하는 것으로 밝혀졌다. 또한 $0.4{\mu}m$의 cell culture insert를 삽입한 2조배양계를 이용하여 Micrococcus sp. LG-5의 살조유형을 조사한 결과, Micrococcus sp. LG-5는 $0.4{\mu}m filter$에 의해 C. polykirkoides와 격리된 상태에서도 C. polykirkoides를 살조시켜, 세포외로 물질을 분비하여 살조시키는 살조물질 분비형으로 밝혀졌다. 또한 Micrococcus sp. LG-5의 배양여과액의 최종농도가 $5{\%}, 10{\%}$가 되도록 첨가한 경우, C. polykrikoides의 개체수는 급격히 감소하여 3시간 경과 후에 centrol에 비해 각각 $30{\%}$와 $85{\%}$정도가 살조되었으며, $1{\%}$의 경우, 30시간 후에 $90{\%}$ 이상 살조되었다. 즉, Micrococcus sp. LG-5의 배양여과액의 양에 비례하여 살조효과가 증가하는 경향을 보였으며, 배양여과액 중에 C. polykrikoides를 사멸시키는 살조물질이 존재함을 알 수가 있었다.

• 한국균학회지
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• 제21권2호
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• pp.94-105
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• 1993

동충하초속균은 곤충기생균으로 충체내에 균핵을 형성하며 단일 또는 총생의 stroma에 자낭각을 형성하는 균이다. 채집된 동충하초균은 Cordyceps militaris, C. nutans, C. sphecocephala, Isaria japonica와 Torrubiella sp. 등 5종이었다. 채집된 동충하초의 분리를 위하여 동충하초의 자실체를 샤레 뚜껑에 tape로 고정시킨 후 water agar가 들은 샤레에 짝을 맞추어 놓으면 자낭포자가 떨어지며 3시간 후 발아한 포자를 PDA에 이식하여 분리하였다. C. nutans와 C. militaris의 균사생장이 가장 우수한 배지는 Hamada media이며 complete media와 감자한천배지에서도 균사생장이 좋은 것으로 나타났다. 탄소원으로는 Mannose와 C. militaris와 C. nutans가 균사생장이 양호하였고 질소원으로는 glutamic acid에서 C. militaris가 asparagine에서는 C. nutans가 균사생장이 양호하였다. Vitamine은 Thiamine-HCI, Biotine, Nicotinic acid 모두 C. militaris와 C. nutans의 균사생장에 비슷하였다. C. nutans의 분생포자를 접종하였을 때 배추흰나비 유충, 노린재, 멸강나방, 배추좀나방은 살충력이 높았고, 메뚜기는 50%, 잣나무넓적잎벌은 12%의 살충력이 있으나 진딧물과 오리나무잎벌에서는 살충력이 없었다. C. nutans는 노린재에서만 채집되나 다른 곤충에도 살충효과가 인정되었다. 쌀가루 5g, 밀가루 5g에 물을 100ml을 넣고 배양한 것이 균사생장과 자실체 형성은 잘 되었으나 형성된 자실체는 완전한 동충하초가 아니고 분생포자의 덩어리라는 것이 현미경에 의해 관찰되었다.

• Molecules and Cells
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• 제38권4호
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• pp.327-335
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• 2015

Piperlongumine, a natural alkaloid isolated from the long pepper, selectively increases reactive oxygen species production and apoptotic cell death in cancer cells but not in normal cells. However, the molecular mechanism underlying piperlongumine-induced selective killing of cancer cells remains unclear. In the present study, we observed that human breast cancer MCF-7 cells are sensitive to piperlongumine-induced apoptosis relative to human MCF-10A breast epithelial cells. Interestingly, this opposing effect of piperlongumine appears to be mediated by heme oxygenase-1 (HO-1). Piperlongumine upregulated HO-1 expression through the activation of nuclear factor-erythroid-2-related factor-2 (Nrf2) signaling in both MCF-7 and MCF-10A cells. However, knockdown of HO-1 expression and pharmacological inhibition of its activity abolished the ability of piperlongumine to induce apoptosis in MCF-7 cells, whereas those promoted apoptosis in MCF-10A cells, indicating that HO-1 has anti-tumor functions in cancer cells but cytoprotective functions in normal cells. Moreover, it was found that piperlongumine-induced Nrf2 activation, HO-1 expression and cancer cell apoptosis are not dependent on the generation of reactive oxygen species. Instead, piperlongumine, which bears electrophilic ${\alpha},{\beta}$-unsaturated carbonyl groups, appears to inactivate Kelch-like ECH-associated protein-1 (Keap1) through thiol modification, thereby activating the Nrf2/HO-1 pathway and subsequently upregulating HO-1 expression, which accounts for piperlongumine-induced apoptosis in cancer cells. Taken together, these findings suggest that direct interaction of piperlongumine with Keap1 leads to the upregulation of Nrf2-mediated HO-1 expression, and HO-1 determines the differential response of breast normal cells and cancer cells to piperlongumine.

• 미생물학회지
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• 제41권1호
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• pp.18-23
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• 2005

이 연구는 새우양식장에서 분리된 Lactobacillus sp. JK-8의 생리적 특성을 규명하기 위하여 실시되었다. 균주 JK-8을 MRS 배지에서 배양하였고, 형태 및 생리학적 특성에 대하여 조사하였으며, BIOLOG시험을 통하여 이 세균은 Lactobacillus속으로 동정되었다. 배양기간 동안에 균주 JK-8의 생장과 PH변화를 조사하였으며, 생성되는 유기산(lactic acid와 acetic acid)은 JK-8 배양의 생장과 비례하는 것을 확인하였다. Lactic acid와 acetic acid의 농도는 각각 192.8 mM과 43.6 mM이었으며, 초기 pH 7.0은 배양기간동안 3.8로 감소하였다. 8가지 대상 세균에 대하여 5배로 농축된 배양 상등액에 처리하여 살균효과를 조사하였으며, 이 연구에서 모든 대상 세균들은 배양3시간 이내에 완전히 살균되었다. pH조절을 하지 안은 JK-8 배양에서 대상세균들에 대한 항균효과가 있는 것이 관찰되었으나, pH가 조절된 배양에서는 거의 관찰되지 않았다. 대사산물로서 lactic acid와 acetic acid의 분리하기 위하여 HPLC를 사용하였으며, GC-MS를 이용하여 이들 대사산물을 확인하였다.

• The Korean Journal of Physiology and Pharmacology
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• 제7권1호
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• pp.9-14
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• 2003

Recent studies indicated that cancer cells become resistant to ionizing radiation (IR) and chemotherapy drugs by enhanced DNA repair of the lesions. Therefore, it is expected to increase the killing of cancer cells and reduce drug resistance by inhibiting DNA repair pathways that tumor cells rely on to escape chemotherapy. There are a number of key human DNA repair pathways which depend on multimeric polypeptide activities. For example, Ku heterodimer regulatory DNA binding subunits (Ku70/Ku80) on binding to double strand DNA breaks (DSBs) are able to interact with 470-kDa DNA-dependent protein kinase catalytic subunit (DNA-PKcs), and are essential for DNA-dependent protein kinase (DNA-PK) activity. It has been known that DNA-PK is an important factor for DNA repair and also is a sensor-transmitting damage signal to downstream targets, leading to cell cycles arrest. Our ultimate goal is to develop a treatment of breast tumors by targeting proteins involved in damage-signaling pathway and/or DNA repair. This would greatly facilitate tumor cell cytotoxic activity and programmed cell death through DNA damaging drug treatment. Therefore, we designed a domain of Ku80 mutants that binds to Ku70 but not DNA end binding activity and used the peptide in co-therapy strategy to see whether the targeted inhibition of DNA-PK activity sensitized breast cancer cells to irradiation or chemotherapy drug. We observed that the synthesized peptide (HNI-38) prevented DNA-PKcs from binding to Ku70/Ku80, thus resulting in inactivation of DNA-PK activity. Consequently, the peptide treated cells exhibited poor to no DNA repair, and became highly sensitive to IR or chemotherapy drugs, and the growth of breast cancer cells was inhibited. Additionally, the results obtained in the present study also support the physiological role of resistance of cancer cells to IR or chemotherapy.

• 한국식품과학회지
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• 제30권3호
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• pp.660-664
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• 1998

식염용액에서 휴지미생물(non-growing microorganisms)의 사멸현상과 식염용액에서 미생물의 보호작용이 있다고 알려진 물질의 작용을 시험하였다. L. mesenteroides LA10, S. aureus B3l와 E. coli B34를 완충용액으로 제조한 0, 10, 20, 30%의 식염용액에서 배양하였을 때 각각 pH 6, 7, 5 부근에서 가장 높은 생존율을 나타내었고, 이 pH로부터 산성 또는 염기성쪽으로 변화시키거나 식염농도가 증가할 수록 생존율이 감소하였다. 젖산균 5종과 일반세균 9종 및 효모 2종의 균주를 pH 5, 6, 7로 조절한 10% 식염용액에서 실험해 본 결과 식염에 내성이 강한 pH는 미생물마다 달라 이는 균주의 특성에 속하는 것으로 사료되며 그람양성균이 그람음성균에 비해 식염내성이 높았으며 그람양성균 중에서도 젖산균이 식염에 대한 내성이 두드러지게 컸고 일반세균에서는 S. aureus가 큰 것으로 나타났다. 식염농도의 영향은 물론 pH가 식염용액에서 미생물의 사멸에 큰 영향을 미치는 것으로 나타났다. 식염의 미생물 생육저해작용으로부터 미생물을 보호한다고 알려진 물질들의 보호작용은 관찰되지 않았다.

• 항공우주정책ㆍ법학회지
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• 제1권
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• pp.87-123
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• 1989

The purpose of this thesis is to do a research on suppression of peacetime international terrorism and penal system of terrorists by political and economic means. International terrorism means wanton killing, hostage taking, hijacking, extortion or torture committed or threatened to be comitted against the innocent civilian in peacetime for political motives or purposes provided that international element is involved therein. This research is limited to international terrorism of political purposes in peacetime, especially, hijacking of civil aircraft. Hijacking of civil aircraft include most of international terrorism element in its criminal act and is considered to be typical of international terrorism in view of multinationality of its crews, passengers and transnational borders involved in aircraft hijacking. Civil air transportation of today is a indispensable part of international substructure, as it help connect continuously social cultural and economic network of world community by dealing with massive and swift transportation of passengers and all kinds of goods. Current frequent hijacking of civil aircraft downgrade the safety and trust of air travel by mass slaughter of passengers and massdestruction of goods and endanger indispensable substructure of world community. Considering these facts, aircraft hijacking of today poses the most serious threat and impact on world community. Therefore, among other thing, legal, political, diplomatic and economic sanctions should be imposed on aircraft hijacking. To pursue an effective research on this thesis aircraft hijacking by six Chineses on 5th May, 1983, from mainland China to Seoul, Korea, is chosen as main theme and the Republic of Korea's legal, political and diplomatic dealing and settlement of this hijacking incident along with six hijackers is reviewed to find out legal, political diplomatic means of suppression and solution of international terrorism. Research is focused on Chinese aircraft hijacking, Korea-China diplomatic negotiation, Korea's legal diplomatic handling and settlement of Tak Chang In, mastermind of aircraft hijacking and responses and position of three countries, Korea, China and Taiwan to this case is thoroughly analyzed through reviewing such materials as news reportings and comments of local and international mass media, Korea-China Memorandum, statements of governments of Korea, China and Taiwan, verdicts of courts of Korea, prosecution papers and oral argument by the defendants and lawyers and three antiaircraft hijacking conventions of Hague, Tokyo and Montreal and all the other instruments of international treaties necessary for the research. By using above-mentioned first-hand meterials as yardsticks, legal and political character of Chinese aircraft hijacking is analyzed and reviewed and close cooperation among sovereign states based on spirit of solidarity and strict observance of international treaties such as Hague, Tokyo and Montreal Conventions is suggested as a solution and suppressive means of international terrorism. The most important and indispensable factor in combating terrorism is, not to speak, the decisive and constant resolution and all-out effort of every country and close cooperation among sovereign states based on "international law of cooperation."