scholarly journals Study of Cellular Uptake of Modified Oligonucleotides by Using Time-Resolved Microspectrofluorimetry and Florescence Imaging

2012 ◽  
Vol 27 ◽  
pp. 415-419 ◽  
Author(s):  
P. Praus ◽  
E. Kočišová ◽  
P. Mojzeš ◽  
J. Štěpánek ◽  
F. Sureau
Keyword(s):  
Cell Line ◽  
Cellular Uptake ◽  
Fluorescence Lifetime ◽  
Antisense Oligonucleotide ◽  
Malignant Cell ◽  
Lifetime Data ◽  
Modified Oligonucleotides ◽  
Mcf7 Cells ◽  
Time Resolved ◽  
Modified Oligonucleotide

Fluorescence microimaging and homodyne phase-resolved confocal microspectrofluorimetry were used to monitor the transport of antisense oligonucleotide into cancer MCF7 cells and the subsequent intracellular distribution. Phosphorothioate analog of 15-mer oligoadenylate (dA15) labeled by ATTO 425 was complexed with 5,10,15,20-tetrakis (1-methyl-4-pyridyl) porphyrin (H2TMPyP4) as an uptake-mediating agent. Fluorescence lifetime data within a broad spectral range have revealed properties of both components inside the cell. H2TMPyP4 lifetime inside the cell is not influenced in this malignant cell line, while the lifetime of modified oligonucleotide was found to be slightly shortened.

scholarly journals Frequency domain fluorescence microspectrometry: Application to cellular uptake and drug distribution

2010 ◽  
Vol 24 (3-4) ◽  
pp. 303-307 ◽  
Author(s):  
Petr Praus ◽  
Eva Kocišová ◽  
Peter Mojzeš ◽  
Josef Štepánek ◽  
Franck Sureau ◽  
...  
Keyword(s):  
Cellular Uptake ◽  
Decay Time ◽  
Spectral Region ◽  
High Frequency ◽  
Antisense Oligonucleotide ◽  
Drug Distribution ◽  
Image Intensifier ◽  
Living Cells ◽  
Time Data ◽  
Time Resolved

Time-resolved confocal microspectrofluorometry and fluorescence microimaging were used to monitor how the model antisense oligonucleotide is transported into 3T3 living cells and distributed inside them. Phosphorothioate analog of 15-mer oligothymidylate labeled by ATTO 425 was complexed with Zn(II) 5,10,15,20-tetrakis(4-N-methylpyridyl) porphyrin as an uptake-mediating agent. Homodyne phase-resolved technique based on a high frequency analog modulation of both exciting diode laser and detector image intensifier was used for time-resolved measurements. Decay-time data obtained within a broad range spectral region have provided unique information about the fate of both fluorophores inside the cell.

TARGETING CYCLIN B1 WITH ANTISENSE OLIGONUCLETOTIDES- COATED SUPERPARAMAGNETIC IRON OXIDE NANOPARTICLES

2018 ◽  
Vol 6 (10) ◽  
Author(s):  
Hosam Zaghloul ◽  
Doaa A. Shahin ◽  
Ibrahim El- Dosoky ◽  
Mahmoud E. El-awady ◽  
Fardous F. El-Senduny ◽  
...  
Keyword(s):  
Iron Oxide ◽  
Iron Oxide Nanoparticles ◽  
Cellular Uptake ◽  
Superparamagnetic Iron Oxide ◽  
Cyclin B1 ◽  
Superparamagnetic Iron Oxide Nanoparticles ◽  
Oxide Nanoparticles ◽  
Mcf7 Cells ◽  
M Phase ◽  
The Impact

Antisense oligonucleotides (ASO) represent an attractive trend as specific targeting molecules but sustain poor cellular uptake meanwhile superparamagnetic iron oxide nanoparticles (SPIONs) offer stability of ASO and improved cellular uptake. In the present work we aimed to functionalize SPIONs with ASO targeting the mRNA of Cyclin B1 which represents a potential cancer target and to explore its anticancer activity. For that purpose, four different SPIONs-ASO conjugates, S-M (1–4), were designated depending on the sequence of ASO and constructed by crosslinking carboxylated SPIONs to amino labeled ASO. The impact of S-M (1–4) on the level of Cyclin B1, cell cycle, ROS and viability of the cells were assessed by flowcytometry. The results showed that S-M3 and S-M4 reduced the level of Cyclin B1 by 35 and 36%, respectively. As a consequence to downregulation of Cyclin B1, MCF7 cells were shown to be arrested at G2/M phase (60.7%). S-M (1–4) led to the induction of ROS formation in comparison to the untreated control cells. Furthermore, S-M (1–4) resulted in an increase in dead cells compared to the untreated cells and SPIONs-treated cells. In conclusion, targeting Cyclin B1 with ASO-coated SPIONs may represent a specific biocompatible anticancer strategy.

Continuous Hypoxia and Glucose Metabolism, The Effects on Genes Expression in Mcf7 Breast Cancer Cell Line

2020 ◽  
Vol 20 ◽  
Author(s):  
Abdel Qader Al Bawab ◽  
Malek Zihlif ◽  
Yazan Jarrar ◽  
Ahmad Saleh
Keyword(s):  
Breast Cancer ◽  
Glucose Metabolism ◽  
Cancer Cells ◽  
Cell Line ◽  
Breast Cancer Cell Line ◽  
Warburg Effect ◽  
Cancer Cell Line ◽  
Mcf7 Cells ◽  
Genetic Changes ◽  
Genes Expression

Background: Hypoxia (deprived oxygen in tissues) may induce molecular and genetic changes in cancer cells. Objective: Investigating the genetic changes of glucose metabolism in breast cancer cell line (MCF7) after exposure to continuous hypoxia (10 and 20 cycles exposure of 72 hours continuously on a weekly basis). Method: Gene expression of MCF7 cells was evaluated using real-time polymerase chain reaction- array method. Furthermore, cell migration and wound healing assays were also applied. Results: It was found that 10 episodes of continuous hypoxia activated Warburg effect in MCF7 cells via the significant up-regulation of genes involved in glycolysis (ANOVA, p value < 0.05). The molecular changes were associated with the ability of MCF7 cells to divide and migrate. Interestingly, after 20 episodes of continuous hypoxia, the expression glycolysis mediated genes has dropped significantly (from 30 to 9 folds). This could be attributed to the adaptive ability of cancer cells. Conclusion: It is concluded that 10 hypoxic episodes increased the survival rate and the aggressiveness of MCF7 cells and induced Warburg effect by up-regulation of the glycolysis mediating genes expression.

scholarly journals Subcellular localization-dependent changes in EGFP fluorescence lifetime measured by time-resolved flow cytometry

2013 ◽  
Vol 4 (8) ◽  
pp. 1390 ◽  
Author(s):  
Ali Vaziri Gohar ◽  
Ruofan Cao ◽  
Patrick Jenkins ◽  
Wenyan Li ◽  
Jessica P. Houston ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Subcellular Localization ◽  
Fluorescence Lifetime ◽  
Time Resolved ◽  
Egfp Fluorescence

scholarly journals Thulium-Doped Silica Fibers with Enhanced Fluorescence Lifetime and Their Application in Ultrafast Fiber Lasers

Fibers ◽  
2018 ◽  
Vol 6 (3) ◽  
pp. 66 ◽  
Author(s):  
Jakub Cajzl ◽  
Pavel Peterka ◽  
Maciej Kowalczyk ◽  
Jan Tarka ◽  
Grzegorz Sobon ◽  
...  
Keyword(s):  
Optical Fibers ◽  
Fluorescence Lifetime ◽  
Energy Levels ◽  
Local Environment ◽  
Alumina Nanoparticles ◽  
Fluorescence Lifetimes ◽  
Transfer Coefficients ◽  
Relaxation Energy ◽  
Time Resolved ◽  
Conventional Solution

In this work we report on the thulium-doped silica-based optical fibers with increased fluorescence lifetime of the 3F4 level thanks to the modification of the local environment of thulium ions by high content of alumina. The determination of the cross-relaxation energy-transfer coefficients from the measurements of the fluorescence lifetimes of the 3F4 and 3H4 energy levels of Tm3+ ions in the experimentally prepared optical fiber is provided as well. Preforms of optical fibers were prepared either by conventional solution-doping of Tm3+ and Al3+ ions or by dispersion-doping of Tm3+ ions with alumina nanoparticles. Optical fibers were characterized by means of Tm, Al, and Ge concentrations, refractive index profiles, optical spectral absorption and luminescence, and by time-resolved fluorescence spectroscopy. Highly aluminium-codoped thulium silicate optical fibers exhibited fluorescence lifetimes of over ~500 μs with maximum value of 756 μs, which means a fluorescence lifetime enhancement when compared to the thulium-doped fibers reported elsewhere. We show an application of the thulium-doped fiber in a compact all-fiber ring laser that is passively mode-locked by using graphene-based saturable absorber. The output pulsewidth and repetition rate were 905 fs and 32.67 MHz, respectively.

scholarly journals The biochemical resolving power of fluorescence lifetime imaging

2021 ◽  
Author(s):  
Andrew L. Trinh ◽  
Alessandro Esposito
Keyword(s):  
Fluorescence Lifetime ◽  
Resolving Power ◽  
Fluorescence Lifetime Imaging ◽  
Time Resolved ◽  
Instrument Response Function ◽  
Lifetime Imaging ◽  
Use Of Time ◽  
Single Living Cells ◽  
Microscopy Techniques

AbstractA deeper understanding of spatial resolution in microscopy fostered a technological revolution that is now permitting us to investigate the structure of the cell with nanometer resolution. Although fluorescence microscopy techniques enable scientists to investigate both the structure and biochemistry of the cell, the biochemical resolving power of a microscope is a physical quantity that is not well-defined or studied. To overcome this limitation, we carried out a theoretical investigation of the biochemical resolving power in fluorescence lifetime imaging microscopy, one of the most effective tools to investigate biochemistry in single living cells. With the theoretical analysis of information theory and Monte Carlo simulations, we describe how the ‘biochemical resolving power’ in time-resolved sensing depends on instrument specifications. We unravel common misunderstandings on the role of the instrument response function and provide theoretical insights that have significant practical implications in the design and use of time-resolved instrumentation.

scholarly journals Cytotoxic Properties of Lyophilized Beers in a Malignant Cell Line

2014 ◽  
Vol 05 (01) ◽  
pp. 45-51 ◽  
Author(s):  
Carmela Spagnuolo ◽  
Idolo Tedesco ◽  
Maria Grazia Volpe ◽  
Stefania Bilotto ◽  
Maria Russo ◽  
...  
Keyword(s):  
Cell Line ◽  
Malignant Cell ◽  
Malignant Cell Line

scholarly journals A parameter estimation method for fluorescence lifetime data

2015 ◽  
Vol 8 (1) ◽  
Author(s):  
Daniel Sewell ◽  
Hajin Kim ◽  
Taekjip Ha ◽  
Ping Ma
Keyword(s):  
Parameter Estimation ◽  
Fluorescence Lifetime ◽  
Estimation Method ◽  
Lifetime Data ◽  
Parameter Estimation Method
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