• Ocean and Polar Research
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• 제31권4호
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• pp.349-357
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• 2009

Ballast water is widely recognized as a serious environmental problem due to the risk of introducing non-indigenous aquatic species. In this study we aimed to investigate measures which can minimize the transfer of aquatic organisms from ballast water. Securing more reliable technologies to determine the viability of aquatic organisms is an important initiative in ballast water management systems. To evaluate the viability of marine phytoplankton, we designed the staining methods of fluorescein diacetate (FDA) and Calcein-AM assay on each target species belonging to different groups, such as bacillariphyceae, dinophyceae, raphidophyceae, chrysophyceae, haptophyceae and chlorophyceae. The FDA method, which is based on measurements of cell esterase activity using a fluorimetric stain, was the best dye for determining live cells of almost all phytoplankton species, except several diatoms tested in this study. On the other hand, although fluorescence of Calcein-AM was very clear for a comparatively longer time, green fluorescence per cell volume was lacking in most of the tested species. According to the Flow CAM method, which is a continuous imaging technique designed to characterize particles, green fluorescence values of stained cells by FDA were significantly higher than those of Calcein-AM treatments and control, implying that the Flow CAM using FDA assay could be adapted as an important tool for distinguishing living cells from dead cells. Our results suggest that the FDA and Calcein-AM methods can be adapted for use on phytoplankton, though species-specific characters are greatly different from one organism to another.

• Journal of Pharmaceutical Investigation
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• 제36권5호
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• pp.309-314
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• 2006

The multicellular layers(MCL) of human cancer cells is a three dimensional(3D) in vitro model for human solid tumors which has been used primarily for the assessment of avascular penetration of anti-cancer drugs. For anti-cancer drugs with penetration problem, MCL represents a good experimental model that can provide clinically relevant data. Calcein-AM is a fluorescent dye that demonstrates the cellular vitality in a graded manner in cancer cell culture system. In the present study, we evaluated the use of calcein-AM for determination of anti-proliferative activity of anti-cancer agents in MCL model of DLD-1 human colorectal cancer cells. Optical sectioning of confocal imaging was compromised with photonic attenuation and penetration barrier in the deep layers of MCL. By contrast, fluorescent measurement on the cryo-sections provided a feasible alternative. Cold pre-incubation did not enhance the calcein-AM distribution to a significant degree in MCL of DLD-1 cells. However, the simultaneous determination of drug penetration and cellular vitality appeared to be possible in drug treated MCL. In conclusion, these data suggest that calcein-AM can be used for the simultaneous determination of drug-induced anti-proliferative effect and drug penetration in MCL model.

• Journal of Photoscience
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• 제9권2호
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• pp.518-520
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• 2002

Photodynamic therapy (PDT) is a treatment modality based on photochemical reaction and the resultant cytotoxic reactive oxygen species. The platelet thrombus formation leading to stasis observed in vivo during PDT is called vascular shut down (VSD) effect. To investigate the mechanism of the VSD effect, we observed Human Umblical Vein Endothelial Cell (HUVEC) injury induced by photochemical reaction. We observed cell retraction and blebbing after PDT. It seems that the injury was not fetal and only morphological change. Then, the cytoplasm was stained by Calcein-AM and subendothelial area was evaluated from fluorescence microscopy. The rate of subendothelial area after PDT increased significantly. Second, we investigated interaction between neutrophils and HUVEC. Human promyelocytic leukemia cells (HL-60) were differentiated into neutrophil by incubation with all-trans retinoic acid. Calcein-AM labeled neutrophil adhesion to HUVEC was evaluated from fluorescence microscopy. PDT-induced neutrophil adhesion to HUVEC depended more on the exposure of subendothlial area than on neutrophil activation. This result suggests that there is a certain interaction between neutrophil and HUVEC during PDT.

• Archives of Pharmacal Research
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• 제18권2호
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• pp.84-89
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• 1995

The complexation and physical characteristics of egg phosphatidylcholine (PC) liposome containing amphotericin B(AmB) were investigated through circular dichrosim(CD) spectra, the size distribution, the turbidity change, and the calcein release. CD spectra of AmB-containing egg PC mxture exhibited a positive peak around 330 nm indicative of complexation of AmB and four negative peaks. The positive peak increased up to $2.2{\;}millidegree/{\mu}g$ AmB as AmB contents increased up to 12% (w/w), suggesting that AmB-phospholipid complexation was promoted by the antibiotics. The effective diameter of liposomesa by dynamic light scattering decreased from 450 nm to 220 nm as the amount of AmB in liposomes increased from o to 30% (w/w). The complexation may be responsible for the reduction in size. On the other hand, at around 1 mN deoxycholate (DOC), the reltive turbidities of 5 and 10% (w/w) AmB-containing liposome suspension were less than 1 probably due to the soblubilization of the complex, while those of pure PC liposome suspension were larger than 1 at the same concentration. Deoxycholate-induced release of liposomes, indicating the intercalation of the drug into the bilayers. Therefore, it is concluded that in AmB/eggPC/water system, AmB-phospholipid complexcoexists with AmB-containing liposomes.

• 생명과학회지
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• 제18권9호
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• pp.1244-1248
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• 2008

본 연구에서는 다양한 천연 추출물의 P-gp 저해능의 고속 탐색을 통하여 새로운 화학감작제 후보물질을 발굴하고자 하였다. P-gp 활성에 대한 천연 추출물의 저해능은 P-gp이 과발현된 L-MDR1 세포주를 이용하여 대표적인 P-gp 기질 약물인 calcein AM의 세포 내 축적 정도를 측정함으로써 평가하였다. 강황 및 울금은 가장 강력한 P-gp 기능 저해를 나타내었고, 이외에도 Mentrasto, 취호초, 봉출, Rakta chandan, 강진향, 소목, 노회 등의 순으로 P-gp 기능 저해능을 보였다. 이들 추출물에서 P-gp 저해능을 보이는 성분을 확인하기 위하여 LC/MS/MS 분석을 수행한 결과, 기존에 P-gp 활성을 저해한다고 잘 알려진 curcumin 이외에, 다양한 플라보노이드 화합물이 질량 스펙트럼 DB 검색을 통하여 확인되었다. In vitro 연구 결과를 통하여 상기의 천연 추출물이 P-gp 활성을 저해하는 성분을 함유하고 있음을 확인하였다. 향후 이들 천연 추출물의 화학감작제 후보물질로의 사용 가능성에 대한 in vivo 연구가 필요할 것이다.

• 한국해양바이오학회지
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• 제1권3호
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• pp.213-217
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• 2006

본 연구는 황백에 함유되어 있는 주요 화합물인 berberine, palmatine, limonin 및 rutaecarpine의 CYP2D6 및 p-glycoprotein 활성에 대한 저해정도를 탐색함으로써, 황백을 다른 양약과 병용시 약물상호작용을 유발할 수 있는 가능성을 평가하고자 하였다. 인체 간 마이크로좀 시료에 CYP2D6 동효소의 기질약물인 dextromethorphan과 NADPH 재생성계 및 저해제 ($200{\mu}M$)를 첨가한 후 반응시켜 생성된 대사물을 LC/MS/MS를 이용하여 정량하여 CYP2D6 동효소 활성의 변화를 평가하였다. 또한 약물수송단백인 p-glycoprotein의 활성은 L-MDR1 세포주를 이용한 calcein AM 축적 실험을 통하여 평가하였다. 그 결과 식물 알카로이드인 berberine에서 강력한 CYP2D6 활성 저해능을 관찰하였으며, 저해 효과는 농도 의존적으로 증가하였으며, mechanism-based 저해 기전을 나타내었다. 그러나 limonine과 rutaecarpine은 CYP2D6 저해 활성을 보이지 않았고, p-glycoprotein 기능에 대해서는 평가한 어떤 화합물도 저해 활성을 나타내지 않았다. 황백의 주요 성분인 berberine의 CYP2D6 활성 저해능을 고려할 때, 황백을 CYP2D6 기질약제와 병용시 약물상호작용을 유발할 가능성을 보여준다. 이러한 황백의 CYP2D6를 매개로한 임상적인 약물상호작용 가능성은 임상시험을 통하여 추가적인 검정이 필요할 것으로 사료된다.

• Journal of Pharmaceutical Investigation
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• 제40권5호
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• pp.269-275
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• 2010

P-gp plays a critical role in drug disposition and represents a mechanism for the development of multidrug resistance. Flavonoids, a major class of natural compounds widely present in foods and herbal products, have been shown to inhibit P-gp. Therefore, the aim of this study was to identify new candidate chemosensitizers by screening various plant extracts. The ability of natural plant extracts to inhibit P-gp activity was assessed by measuring cellular accumulation of calcein AM, daunorubicin and vincristine in P-gp overexpressing MDCKII-MDR1 cells. Among more than 800 plant extracts, eight were found to inhibit P-gp activity. Curcuma aromatica extract produced greatest inhibition, followed by Curcuma longa and Dalbergia odorifera extracts. Extracts of Aloe ferox, Curcuma zedoariae rhizome, Zanthoxylum planispinum, and Ageratum conyzoides showed moderate inhibitory effects. Curcumin and quercetin exhibited similar inhibition of P-gpmediated efflux of daunorubicin and vincristine, and flavones had a lesser effect. When chemosensitizing effect was evaluated by measuring daunorubicin sensitivity to MDCKII-MDR1 cells in the presence of natural plant extracts, Curcuma aromatica showed the most potent chemosensitizing effect based on daunorubicin cytotoxicity. In conclusion, natural plant extracts such as Curcuma aromatica can potently inhibit P-gp activity and may have potential as a novel chemosensitizers.

• 한국수정란이식학회지
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• 제32권3호
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• pp.221-226
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• 2017

Spermatozoa viability can be assessed by microscopy, flow cytometry, and other methods using fluorescent stain. Flow cytometry can be used to examine the morphological and functional characteristics of spermatozoa in a short time. The purpose of this study was to compare the viability of cryopreserved spermatozoa in Jeju black cattle by two dual fluorescent stain methods. Semen of Jeju black cattle raised in Subtropical Livestock Research Institute, National Institute of Animal Science, RDA were collected with artificial vaginal technique. Sperm was diluted with $Triladyl^{(R)}$-egg yolk diluent and then was performed cryopreservation. There was no significant difference in viability of spermatozoa according to the two dual fluorescent stain methods. However, when the distribution of spermatozoa according to the staining method was compared, the spermatozoa group stained with 6-CFDA/PI was more clearly distinguished than the spermatozoa group stained with calcein AM/PI.

• 대한한의학방제학회지
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• 제32권1호
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• pp.99-109
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• 2024

Objectives : In this study, we investigated the cytoprotective effect of Eriobotrya japonica L. (EJ) extract against Arachidonic acid (AA)+iron-induced oxidative stress. Methods : To confirm the cytoprotective effect of EJ against AA+iron-induced oxidative stress in HepG2 cells, it was evaluated by MTT assay, immunoblot anaylsis, and Calcein-AM/propidium iodide (PI) staining. Additionally, the mechanism of action of the cytoprotective effect was evaluated through molecular mechanisms. Results : EJ (100 ㎍/mL) inhibited Arachidonic acid (AA)+iron-induced cell death in a concentration-dependent manner. It also inhibited AA+iron-induced mitochondrial dysfunction and ROS production. EJ activated the LKB1-AMPK signaling pathway. Conclusions : In conclusion, EJ has the ability to protect liver cells from oxidative stress, indicating that it is related to AMPK-LKB1 signaling pathways.

• Clinical and Experimental Pediatrics
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• 제46권7호
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• pp.702-709
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• 2003

목 적 : $IFN{\gamma}$는 다양한 암세포에서 $TNF{\alpha}$와 FAS/CD95 수용체 발현을 증가시키거나 caspase나 Bcl-2 가족의 활성화를 조절하여 $TNF{\alpha}$와 FAS/FASL 유도성 세포고사를 촉진한다. 신경모세포종에서 $IFN{\gamma}$와 $TNF{\alpha}$는 협동적으로 세포 분화를 유도하거나 성장 억제를 일으킨다. 또한 일부 신경모세포종에서 자연적인 FAS 수용체 발현에도 불구하고 그 리간드 자극에 의한 세포고사 유도에는 실패하였고 $IFN{\gamma}$ 투여로 이를 극복할 수 있음이 보고되었다. 본 연구에서는 $IFN{\gamma}$가 $TNF{\alpha}$나 길항적 FAS/CD95 항체 유도성 세포고사를 촉진할 수 있는지 여부를 다양한 항암제에 대한 내성을 가지고 있는 신경모세포종 세포주를 이용하여 알아보았다. 방 법 : CHLA-15, CHLA-90와 LA-N-2 신경모세포종 세포주를 IMDM 배지로 배양하였고 유전자 재조합 $IFN{\gamma}$, $TNF{\alpha}$, 길항적 FAS/CD95 항체(CH-11)를 투여하였다. 세포 생존율은 형광기질인 calcein-AM을 이용한 DIMSCAN을 통하여 측정하였고, 세포고사 정도는 Annexin V-PE와 7-ADD염색을 이용한 유식세포 분석기를 통하여 분석하였고 pancaspase and caspase-8 억제 실험을 통하여 확인하였다. TNF와 FAS/CD95 수용체 표현은 각각에 대한 단클론 항체와 PE가 결합된 이차 항체를 이용하여 유식세포 분석기로 알아보았다. 결 과 : $IFN{\gamma}$ 또는 $TNF{\alpha}$ 단독 투여로는 모든 세포주에서 의의있는 세포 독성을 유도하지 못 했으나 $IFN{\gamma}$와 $TNF{\alpha}$을 병행 투여시에는 CHLA-15과 CHLA-90 세포주에서 의의있는 세포 생존율 감소와 공통 capase경로를 통한 세포고사를 협동적으로 촉진하였다. 또한 길항적 FAS/CD95 항체 단독 투여 시에는 모든 세포주에서 세포 생존율의 변화가 없었으나 $IFN{\gamma}$ 전 처치 후 투여 시에는 CHLA-90 세포주에서 현저한 세포 생존율 변화 및 세포고사를 유도하였다. $INF{\gamma}$ 치료 후 TNFRI와 FASR의 발현이 모든 세포주에서 현저히 증가하였는데 이는 일부 감수성이 있는 신경모세포종에서 $INF{\gamma}$에 의한 $TNF{\alpha}$와 FAS/CD95수용체 유도성 세포고사 촉진의 한 기전이 될 것으로 사료된다. 결 론: 일부 신경모세포종에서 $IFN{\gamma}$가 $TNF{\alpha}$와 길항적 FAS/CD95 항체 유도성 세포고사를 감작화 시켰으며 이는 수용체 발현의 증가와 동반되었다.