• 제목/요약/키워드: fluorescence dyes

검색결과 70건 처리시간 0.028초

Different modes of antibiotic action of homodimeric and monomeric bactenecin, a cathelicidin-derived antibacterial peptide

  • Lee, Ju-Yeon;Yang, Sung-Tae;Kim, Hyo-Jeong;Lee, Seung-Kyu;Jung, Hyun-Ho;Shin, Song-Yub;Kim, Jae-Il
    • BMB Reports
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    • 제42권9호
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    • pp.586-592
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    • 2009
  • The bactenecin is an antibacterial peptide with an intramolecular disulfide bond. We recently found that homodimeric bactenecin exhibits more potent antibacterial activity than the monomeric form and retains its activity at physiological conditions. Here we assess the difference in the modes of antibiotic action of homodimeric and monomeric bactenecins. Both monomeric and dimeric bactenecins almost completely killed both Staphylococcus aureus and E. coli within 10-30 min at concentrations of $8-16\;{\mu}M$. However, exposure to liposomes elicited an increase in the fluorescence quantum yield from a tryptophan-containing monomeric analog, while the homodimeric analog showed a significant reduction in fluorescence intensity. Moreover, unlike the monomer, the homodimer displayed apparent membrane-lytic activity enabling release of various sized dyes from liposomes, and rapidly and fully depolarized the S. aureus membrane. Together, our results suggest that homodimeric bactenecin forms pores in the bacterial membrane, while monomeric one penetrates through the membrane to target intracellular molecules/organelles.

Multimodal Nonlinear Optical Microscopy for Simultaneous 3-D Label-Free and Immunofluorescence Imaging of Biological Samples

  • Park, Joo Hyun;Lee, Eun-Soo;Lee, Jae Yong;Lee, Eun Seong;Lee, Tae Geol;Kim, Se-Hwa;Lee, Sang-Won
    • Journal of the Optical Society of Korea
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    • 제18권5호
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    • pp.551-557
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    • 2014
  • In this study, we demonstrated multimodal nonlinear optical (NLO) microscopy integrated simultaneously with two-photon excitation fluorescence (TPEF), second-harmonic generation (SHG), and coherent anti-Stokes Raman scattering (CARS) in order to obtain targeted cellular and label-free images in an immunofluorescence assay of the atherosclerotic aorta from apolipoprotein E-deficient mice. The multimodal NLO microscope used two laser systems: picosecond (ps) and femtosecond (fs) pulsed lasers. A pair of ps-pulsed lights served for CARS (817 nm and 1064 nm) and SHG (817 nm) images; light from the fs-pulsed laser with the center wavelength of 720 nm was incident into the sample to obtain autofluorescence and targeted molecular TPEF images for high efficiency of fluorescence intensity without cross-talk. For multicolor-targeted TPEF imaging, we stained smooth-muscle cells and macrophages with fluorescent dyes (Alexa Fluor 350 and Alexa Fluor 594) for an immunofluorescence assay. Each depth-sectioned image consisted of $512{\times}512$ pixels with a field of view of $250{\times}250{\mu}m^2$, a lateral resolution of $0.4{\mu}m$, and an axial resolution of $1.3{\mu}m$. We obtained composite multicolor images with conventional label-free NLO images and targeted TPEF images in atherosclerotic-plaque samples. Multicolor 3-D imaging of atherosclerotic-plaque structural and functional composition will be helpful for understanding the pathogenesis of cardiovascular disease.

Adverse effect of IL-6 on the in vitro maturation of porcine oocytes

  • Yi, Young-Joo;Adikari, Adikari Arachchige Dilki Indrachapa;Moon, Seung-Tae;Heo, Jung-Min;Lee, Sang-Myeong
    • 농업과학연구
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    • 제48권3호
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    • pp.607-615
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    • 2021
  • Cytokines are protein mediators that possess the ability to assist cell-to-cell communication in immune system-related activities. In general, pathogen endotoxins activate the release of inflammatory mediators, and with time, there is an increase in the cytokine levels in the body. Interleukin (IL)-6 mediates the acute-phase inflammatory response, and elevated IL-6 levels have been reported in peritoneal fluids of women with pelvic inflammation and endometriosis, thereby associating it with oocyte quality and infertility. To overcome subfertility or infertility in humans and animals, the present study was done to examine the effect of recombinant IL-6 on porcine oocytes matured in vitro and subsequently to determine the fertilization rate and embryo development. Porcine oocytes were incubated with varying concentrations of IL-6 (0 - 2 ㎍·mL-1) for 44 h followed by in vitro fertilization and culturing of the oocytes. The oocytes or embryos were fixed with 3.7% paraformaldehyde (PFA) and stained with fluorescence dyes, and the meiotic spindle, chromosome organization, fertilization status and embryo development were subsequently assessed under a fluorescence microscope. We observed induction of an abnormal meiotic spindle alignment in the oocytes incubated with IL-6 compared to the control oocytes incubated without IL-6. Moreover, significantly decreased fertilization rates and embryo development were observed for oocytes incubated with IL-6 (p < 0.05). Thus, an increased IL-6 level during oocyte maturation could be associated with fertilization failure due to an aberrant chromosomal alignment and a disruption of the cortical granules. Taken together, our results indicate that successful assisted reproduction can be achieved by controlling the levels of inflammatory cytokines.

Synthesis and Characterization of Upconversion Nanoparticles for Cancer Therapy

  • 최승유;김보배;김은비;이승우;전선아;박태정
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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    • pp.420.2-420.2
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    • 2016
  • Various fields have been paid attention to upconversion nanoparticles (UCNPs) because of its unique optical properties. Moreover, to use the UC luminescent techniques through cell images for identified apoptosis/necrosis of cancer cells have been performed. They have been studied for a versatile biomedical application such as a biosensing tool, or delivery of active forms of medicines inside living cells. UCNPs have distinctive characteristics such as photoluminescence, special emission, low background fluorescence signal and good colloidal stability, which have many advantages compared with the organic dyes and quantum dots. UCNPs have not only a great potential for imaging (UC luminescence) but also therapies (photo-thermal therapy, PTT and photo-dynamic therapy, PDT) in cancer diagnostics. Therefore, we report the enhancement of upconversion red emission in NaYF4:Yb3+,Er3+ nanoparticles, synthesized via solid-state method with the thermal decomposition of trifluoroacetate as precursors and organic solvent at a high boiling point. The UCNPs have an emission in the field of near infrared wavelength, cubic shape and nano-size in length. In this study, we will further investigate it for cancer therapy with NIR optical detection onto the solid substrate.

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Multiplex Real-Time PCR을 이용하여 6종의 주요 잇몸질환 유발 미생물을 동시에 검출하는 기법 (Multiplex Real-Time PCR for Simultaneous Detection of 6 Periodontopathic Bacteria)

  • 조홍범
    • 미생물학회지
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    • 제49권3호
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    • pp.292-296
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    • 2013
  • 본 연구는 multiplex real-time PCR을 이용하여 Actinobacillus actinomycetemcomitans, Campylobacter rectus, Porphyromonas gingivalis, Tannerella forsythus, Treponema denticola, Prevotella intermedia 등과 같은 6종의 주요 치주 질환 원인 미생물들을 동시에 검출할 수 있는 분석 방법에 관한 것이다. 4개의 형광 염료를 사용하여 internal control과 함께 3개의 균종씩 나누어 분석하였으며, 분석 대상 균종 간 그리고 다른 종류의 구강 미생물 균종과의 간섭과 교차 반응이 없음을 확인하였다. 본 연구의 multiplex real-time PCR은 타액과 플라그 등의 다양한 샘플에 포함되어 있는 각 미생물들을 정성, 정량적으로 분석할 수 있었으며, 치주염 환자와 건강한 사람들에 대한 비교 분석 결과 분명한 차이를 발견 할 수 있었다.

Poly(dimethylsiloxane) 미세 구조물의 신속한 기하학적 패터닝 (Rapid Topological Patterning of Poly(dimethylsiloxane) Microstructure)

  • 김보열;송환문;손영아;이창수
    • 한국염색가공학회지
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    • 제20권1호
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    • pp.8-15
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    • 2008
  • We presented the modified decal-transfer lithography (DTL) and light stamping lithography (LSL) as new powerful methods to generate patterns of poly(dimethylsiloxane) (PDMS) on the substrate. The microstructures of PDMS fabricated by covalent binding between PDMS and substrate had played as barrier to locally control wettability. The transfer mechanism of PDMS is cohesive mechanical failure (CMF) in DTL method. In the LSL method, the features of patterned PDMS are physically torn and transferred onto a substrate via UV-induced surface reaction that results in bonding between PDMS and substrate. Additionally we have exploited to generate the patterning of rhodamine B and quantum dots (QDs), which was accomplished by hydrophobic interaction between dyes and PDMS micropatterns. The topological analysis of micropatterning of PDMS were performed by atomic force microscopy (AFM), and the patterning of rhodamine B and quantum dots was clearly shown by optical and fluorescence microscope. Furthermore, it could be applied to surface guided flow patterns in microfluidic device because of control of surface wettability. The advantages of these methods are simple process, rapid transfer of PDMS, modulation of surface wettability, and control of various pattern size and shape. It may be applied to the fabrication of chemical sensor, display units, and microfluidic devices.

다목적 콘택트렌즈 용액에 대한 미용 칼라렌즈의 탈색 관찰 (Bleaching Observation of Cosmetic Color Lenses According to Multipurpose Contact Lens Solutions)

  • 김효진
    • 한국안광학회지
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    • 제19권3호
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    • pp.295-303
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    • 2014
  • 목적: 본 연구는 국내에서 유통되는 미용 칼라 콘택트렌즈에 대하여 렌즈 관리에 이용되는 다목적 콘택트렌즈 용액에 의한 탈색을 관찰하고자 하였다. 방법: 6개월용 착용렌즈로 굴절력이 0.00 D이며, 주변부가 다른 제조공법으로 착색된 세 가지 칼라 콘택트렌즈를 이용하였고(타입 1: pigment application method, 타입 2: chemical bonding process, 타입 3: sandwich method), 다목적용액은 성분이 다른 두 종류를 사용하였다. 각각의 칼라 콘택트렌즈는 다목적용액에서 20일간 보관하면서 1일 15초 동안 소용돌이 혼합(vortexing) 하였다. 소용돌이 혼합 전과 후에 형광흡광도, 표면사진 그리고 명도지수와 색좌표지수를 측정하여 탈색정도를 관찰하였다. 결과: 두 종류의 다목적용액에서 모든 타입의 미용 칼라 콘택트렌즈의 형광 흡광도 값은 소용돌이 혼합 전과 후에 통계적으로 유의한 차이가 없었다. 표면사진은 렌즈의 전면은 모든 타입에서 매끄러웠고, 후면은 타입 3은 1과 2 보다 돌출된 정도가 적었다. 소용돌이 혼합 전과 후 렌즈 표면색의 색차 변화는 타입 3이 타입 1과 2보다 유의하게 변화도가 작았으나 모두 허용오차 안에 들었다. 결론: 소프트 콘택트렌즈 다목적 용액에 의한 미용 칼라 콘택트렌즈의 탈색은 형광 흡광도와 표면색 측정에서 관찰되지 않았다. 그러나 콘택트렌즈의 제조방법에 따라 렌즈 후면의 돌출된 정도는 달랐다.

국립중앙박물관 소장 적의본과 폐슬본 채색 안료 및 염료 분석 (Analysis on the Pigments and Dyes of the Patterns for Jeogui and Pyeseul of National Museum of Korea)

  • 윤은영;강형태
    • 박물관보존과학
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    • 제13권
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    • pp.13-22
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    • 2012
  • 국립중앙박물관 소장 적의본과 폐슬본은 20세기 초에 제작된 것으로 모두 지본채색되어 있다. 두 본에 사용된 채색 안료 및 염료에 대한 비파괴분석을 통해 채색 재료를 확인하고자 하였다. 채색 안료의 성분분석에는 XRF를 이용하였다. 적의본의 안료 분석결과 백색은 연분, 흑색은 먹, 황색은 석황, 적색은 진사와 연단, 녹색은 구리와 비소화합물 또는 석청과 석황을 혼합하여 사용한 것으로 추정되며 기타색상으로 황동을 사용하였다. 폐슬본에 사용된 백색, 흑색, 황색, 녹색은 적의본에 사용된 안료와 동일하나 적색은 채색 안료에 차이를 보였다. 한편 적의본과 폐슬본에 사용된 청색은 안료의 종류를 확인이 어려우나 연분과 혼합하여 사용한 것으로 추정된다. 또한 적의본의 청색 한지에 대한 UV-Vis 분광분석 결과 인디고(쪽)으로 염색한 것으로 추정되었다.

Pyrazole과 Pyrazolotriazole 유도체의 합성 및 특성 연구 (Synthesis, Fastness and Spectral Properties of Some New Azo Pyrazole and Pyrazolotriazole Derivatives)

  • Rizk, Hala F.;El-Badawi, Mahmoud A.;Ibrahim, Seham A.;El-Borai, Mohamed A.
    • 대한화학회지
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    • 제54권6호
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    • pp.737-743
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    • 2010
  • 5-Amino-1,3-diaryl-pyrazoles 1a-c 와 다양한 aryl amine의diazonium salts를 반응시켜서 1,3-diaryl-5-amino-4-arylazopyrazoles 3a-l을 합성하였으며, 몇 가지 화합물은 5-amino-1,3-diaryl-4-nitroso-1H-pyrazoles 2a-c와 aryl amine의 diazonium salts를 반응시켜서 얻었다. 합성한 azo 유도체 화합물 3a-l을 DMF 용매 속에서 cupric acetate와 산화반응시켜서 2,4,6-triaryl-2,4-dihydropyrazolo [4,3-d]-1,2,3-triazoles 4a-l을 합성하였으며, 합성한 cyclic triazoles에 대한 형광 특성을 측정하였다. 한편, Diazotization of sodium nitrite/ortho-phosphoric acid 조건에서 5-amino-1,3-diaryl-1H-pyrazoles 1a-c를 diazotization화 반응시킨 다음에, aryl amines과 반응시켜서 o-aminoazo compounds 5a-f를 합성하였다. 합성한 화합물 5a-f를 pyridine/cupric acetate 반응 조건에서 반응시켜서 triazole 6a-f들을 합성하였으며, 얻어진 화합물 6a-f을 aryl diazonium salts과 반응시켜서 화합물 7a-j을 합성하였다. 합성한 염료 화합물을 polyesters에 분산염료와 정착성을 측정하였다.

Effect of Polygonati Sibirici Rhizoma on Cell Viability in Human Glioma Cells

  • Kim, Min-Soo;Jeong, Ji-Cheon
    • 대한한의학회지
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    • 제29권1호
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    • pp.95-105
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    • 2008
  • Objectives : Although herbal medicines containing flavonoids have been reported to exert anti-tumor activities, it has not been explored whether Hwang-Jeong (Polygonati sibirici Rhizoma, PsR) exerts anti-tumor activity in human glioma. The present study was therefore undertaken to examine the effect of PsR on cell viability and to determine its underlying mechanism in A172 human glioma cells. Methods : Cell viability was estimated by MTT assay. Reactive oxygen species generation and mitochondrial membrane potential were measured by the fluorescence dyes. The phosphorylation of kinases was evaluated by western blot analysis and caspase activity was estimated using colorimetric assay kit. Results : PsR resulted in loss of cell viability in a dose- and time-dependent manner. PsR did not increase reactive oxygen species (ROS) generation and the PsR-induced cell death was also not affected by antioxidants, suggesting that ROS generation is not involved in loss of cell viability. Western blot analysis showed that PsR treatment caused rapid reduction in phosphorylation of extracellular signal-regulated kinase (ERK) without changes in p38 and Jun-NH2-terminal kinase (JNK). U0126, an inhibitor of ERK, increased the PsR-induced cell death, but inhibitors of p38 and JNK did not affect the cell death. PsR induced depolarization of mitochondrial membrane potential. Caspase activity was not stimulated by PsR and caspase inhibitors did not prevent the PsR-induced cell death. Conclusion : Taken together, these findings suggest that PsR results in human glioma cell death through caspaseindependent mechanisms involving down-regulation of ERK.

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