Viscosity sensitive fluorescent dyes with excellent photostability based on hemicyanine dyes for targeting cell membrane

Five potentially environmentally friendly and light-stable hemicyanine dyes were designed based on integrated consideration of photo, environmental, and computational chemistry as well as textile applications. Two of them were synthesized and applied in dyeing polyacrylonitrile (PAN), cotton, and nylon fabrics, and demonstrated the desired properties speculated by the programs. The computer-assisted analytical processes includes estimation of the maximum absorption and emission wavelengths, aquatic environmental toxicity, affinity to fibers, and photo-stability. This procedure could effectively narrow down discovery of new potential dye structures, greatly reduce and prevent complex and expensive preparation processes, and significantly improve the development efficiency of novel environmentally friendly dyes.

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Ca2+–Calmodulin Dependent Wound Repair in Dictyostelium Cell Membrane

Cells ◽

10.3390/cells9041058 ◽

2020 ◽

Vol 9 (4) ◽

pp. 1058

Author(s):

Md. Shahabe Uddin Talukder ◽

Mst. Shaela Pervin ◽

Md. Istiaq Obaidi Tanvir ◽

Koushiro Fujimoto ◽

Masahito Tanaka ◽

...

Keyword(s):

Cell Membrane ◽

Wound Repair ◽

Fluorescent Dyes ◽

De Novo ◽

External Medium ◽

Dictyostelium Cell ◽

Animal Cells ◽

Wound Site ◽

Physiological Phenomenon ◽

Lines Of Evidence

Wound repair of cell membrane is a vital physiological phenomenon. We examined wound repair in Dictyostelium cells by using a laserporation, which we recently invented. We examined the influx of fluorescent dyes from the external medium and monitored the cytosolic Ca2+ after wounding. The influx of Ca2+ through the wound pore was essential for wound repair. Annexin and ESCRT components accumulated at the wound site upon wounding as previously described in animal cells, but these were not essential for wound repair in Dictyostelium cells. We discovered that calmodulin accumulated at the wound site upon wounding, which was essential for wound repair. The membrane accumulated at the wound site to plug the wound pore by two-steps, depending on Ca2+ influx and calmodulin. From several lines of evidence, the membrane plug was derived from de novo generated vesicles at the wound site. Actin filaments also accumulated at the wound site, depending on Ca2+ influx and calmodulin. Actin accumulation was essential for wound repair, but microtubules were not essential. A molecular mechanism of wound repair will be discussed.

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Directional Cooling of Adult Stem Cells

Heat Transfer, Volume 3 ◽

10.1115/imece2006-13490 ◽

2006 ◽

Cited By ~ 1

Author(s):

R. Fuller ◽

R. V. Devireddy

Keyword(s):

Stem Cells ◽

Adipose Tissue ◽

Cell Membrane ◽

Confidence Level ◽

Adult Stem Cells ◽

Fluorescent Dyes ◽

Membrane Integrity ◽

Ice Crystals ◽

Cell Membrane Integrity ◽

Solidification Stage

The effect of directional cooling on the immediate post thaw membrane integrity of adipose tissue derived adult stem cells (ASCs) was investigated using a directional solidification stage (DSS). ASCs were cooled at either 1, 5, 20 or 40 °C/min to an end temperature of −80°C in the presence and absence of a cryoprotective agent (dimethylsulfoxide, DMSO). After freezing to -80°C, the samples were thawed at 200°C/min and the ability of the frozen/thawed ASCs to exclude fluorescent dyes was assessed. ASCs frozen using the DSS in the presence of 0.85M (or 10% v/v) DMSO were found to have a higher post-thaw cell membrane integrity (confidence level of 99%) when compared with the ASCs frozen in its absence. Intriguingly, a comparison with corresponding data for ASCs that were frozen using a commercially available controlled rate freezer (CRF) suggests that the directionally cooled ASCs (both in the absence and presence of DMSO) exhibit a significantly lower post-thaw cell membrane integrity (confidence level of 95%). This lowering of post-thaw cell membrane integrity for ASCs frozen using the DSS is postulated to be related to the differences in the nature, and the associated damaging effects, of ice crystals formed in the DSS vs. the commercial freezer.

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Study on the Dyeing Properties of Hemicyanine Dyes in Acrylic Fabrics

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.175-176.587 ◽

2011 ◽

Vol 175-176 ◽

pp. 587-592

Author(s):

Chuan Xiang Qin ◽

Ren Cheng Tang ◽

Guo Qiang Chen

Keyword(s):

Partition Coefficient ◽

Fluorescent Dyes ◽

Hydroxyl Groups ◽

Dye Molecules ◽

Dyeing Properties ◽

Hemicyanine Dyes ◽

Acrylic Fabric ◽

Dye Molecule

In this paper, two hemicyanine dyes, DEASPI and DHEASPI-C1, were synthesized and used in acrylic fabrics as fluorescent dyes. The influence of the hydroxyl groups of dye molecules on the dyeing properties was analyzed, and the results showed that the exhaustion value and partition coefficient value decreased a lot when there were two hydroxyl groups attached to the end of dye molecule. The reflectance of the dyed acrylic fabrics with these two fluorescent dyes is higher than 100% in 600 - 700 nm. Moreover, the chromaticity of dyed acrylic fabric was calculated according to the EN-471 standard (2003).

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Probing Nanoelectroporation and Resealing of the Cell Membrane by the Entry of Ca2+ and Ba2+ Ions

International Journal of Molecular Sciences ◽

10.3390/ijms21093386 ◽

2020 ◽

Vol 21 (9) ◽

pp. 3386 ◽

Cited By ~ 4

Author(s):

Wenfei Bo ◽

Mantas Silkunas ◽

Uma Mangalanathan ◽

Vitalij Novickij ◽

Maura Casciola ◽

...

Keyword(s):

Cell Membrane ◽

Time Course ◽

Calcium Release ◽

Fluorescent Dyes ◽

Membrane Damage ◽

Time Lapse ◽

Dose Dependence ◽

Intact Cells ◽

Nanosecond Pulsed Electric Field ◽

Cell Membrane Permeabilization

The principal bioeffect of the nanosecond pulsed electric field (nsPEF) is a lasting cell membrane permeabilization, which is often attributed to the formation of nanometer-sized pores. Such pores may be too small for detection by the uptake of fluorescent dyes. We tested if Ca2+, Cd2+, Zn2+, and Ba2+ ions can be used as nanoporation markers. Time-lapse imaging was performed in CHO, BPAE, and HEK cells loaded with Fluo-4, Calbryte, or Fluo-8 dyes. Ca2+ and Ba2+ did not change fluorescence in intact cells, whereas their entry after nsPEF increased fluorescence within <1 ms. The threshold for one 300-ns pulse was at 1.5–2 kV/cm, much lower than >7 kV/cm for the formation of larger pores that admitted YO-PRO-1, TO-PRO-3, or propidium dye into the cells. Ba2+ entry caused a gradual emission rise, which reached a stable level in 2 min or, with more intense nsPEF, kept rising steadily for at least 30 min. Ca2+ entry could elicit calcium-induced calcium release (CICR) followed by Ca2+ removal from the cytosol, which markedly affected the time course, polarity, amplitude, and the dose-dependence of fluorescence change. Both Ca2+ and Ba2+ proved as sensitive nanoporation markers, with Ba2+ being more reliable for monitoring membrane damage and resealing.

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Selecting Targets for Tumor Imaging: An Overview of Cancer-Associated Membrane Proteins

Biomarkers in Cancer ◽

10.4137/bic.s38542 ◽

2016 ◽

Vol 8 ◽

pp. BIC.S38542 ◽

Cited By ~ 45

Author(s):

Martin C. Boonstra ◽

Susanna W.L. De Geus ◽

Hendrica A.J.M. Prevoo ◽

Lukas J.A.C. Hawinkels ◽

Cornells J.H. Van De Velde ◽

...

Keyword(s):

Membrane Proteins ◽

Cell Membrane ◽

Tumor Targeting ◽

Near Infrared ◽

Fluorescent Dyes ◽

Tumor Imaging ◽

Cancer Targeting ◽

Tumor Visualization ◽

Anchoring Proteins ◽

Membrane Bound

Tumor targeting is a booming business: The global therapeutic monoclonal antibody market accounted for more than $78 billion in 2012 and is expanding exponentially. Tumors can be targeted with an extensive arsenal of monoclonal antibodies, ligand proteins, peptides, RNAs, and small molecules. In addition to therapeutic targeting, some of these compounds can also be applied for tumor visualization before or during surgery, after conjugation with radionuclides and/or near-infrared fluorescent dyes. The majority of these tumor-targeting compounds are directed against cell membrane-bound proteins. Various categories of targetable membrane-bound proteins, such as anchoring proteins, receptors, enzymes, and transporter proteins, exist. The functions and biological characteristics of these proteins determine their location and distribution on the cell membrane, making them more, or less, accessible, and therefore, it is important to understand these features. In this review, we evaluate the characteristics of cancer-associated membrane proteins and discuss their overall usability for cancer targeting, especially focusing on imaging applications.

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Conformation of Ribosomes from Escherichia Coli

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100051062 ◽

1974 ◽

Vol 32 ◽

pp. 210-211

Author(s):

M. Boublik ◽

W. Hellmann ◽

F. Jenkins

Keyword(s):

Binding Sites ◽

Ribosomal Proteins ◽

Fluorescent Dyes ◽

Protein Biosynthesis ◽

Three Dimensional ◽

Spatial Arrangement ◽

Dimensional Structure ◽

Complete Understanding ◽

And Function

The present knowledge of the three-dimensional structure of ribosomes is far too limited to enable a complete understanding of the various roles which ribosomes play in protein biosynthesis. The spatial arrangement of proteins and ribonuclec acids in ribosomes can be analysed in many ways. Determination of binding sites for individual proteins on ribonuclec acid and locations of the mutual positions of proteins on the ribosome using labeling with fluorescent dyes, cross-linking reagents, neutron-diffraction or antibodies against ribosomal proteins seem to be most successful approaches. Structure and function of ribosomes can be correlated be depleting the complete ribosomes of some proteins to the functionally inactive core and by subsequent partial reconstitution in order to regain active ribosomal particles.

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Sarcolemmal permeability changes during early myocardial anoxia

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100084089 ◽

1978 ◽

Vol 36 (2) ◽

pp. 642-643

Author(s):

M. Ashraf ◽

L. Landa ◽

L. Nimmo ◽

C. M. Bloor

Keyword(s):

Cell Membrane ◽

Membrane Permeability ◽

Coronary Artery Occlusion ◽

Artery Occlusion ◽

Cell Membrane Permeability ◽

Enzyme Release ◽

Sprague Dawley ◽

Sprague Dawley Rats ◽

Sarcolemmal Permeability ◽

Membrane Changes

Following coronary artery occlusion, the myocardial cells lose intracellular enzymes that appear in the serum 3 hrs later. By this time the cells in the ischemic zone have already undergone irreversible changes, and the cell membrane permeability is variably altered in the ischemic cells. At certain stages or intervals the cell membrane changes, allowing release of cytoplasmic enzymes. To correlate the changes in cell membrane permeability with the enzyme release, we used colloidal lanthanum (La+++) as a histological permeability marker in the isolated perfused hearts. The hearts removed from sprague-Dawley rats were perfused with standard Krebs-Henseleit medium gassed with 95% O2 + 5% CO2. The hypoxic medium contained mannitol instead of dextrose and was bubbled with 95% N2 + 5% CO2. The final osmolarity of the medium was 295 M osmol, pH 7. 4.

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Flagellar Attachment in Selected Trypanosomes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100072927 ◽

1973 ◽

Vol 31 ◽

pp. 496-497

Author(s):

J. J. Paulin

Keyword(s):

Cell Membrane ◽

Lateral Surface ◽

The Body ◽

Flagellar Pocket ◽

Integral Component ◽

Free Flagellum ◽

Flagellar Axoneme

Movement in epimastigote and trypomastigote stages of trypanosomes is accomplished by planar sinusoidal beating of the anteriorly directed flagellum and associated undulating membrane. The flagellum emerges from a bottle-shaped depression, the flagellar pocket, opening on the lateral surface of the cell. The limiting cell membrane envelopes not only the body of the trypanosome but is continuous with and insheathes the flagellar axoneme forming the undulating membrane. In some species a paraxial rod parallels the axoneme from its point of emergence at the flagellar pocket and is an integral component of the undulating membrane. A portion of the flagellum may extend beyond the anterior apex of the cell as a free flagellum; the length is variable in different species of trypanosomes.

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