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Different Dyes (different + dye)
Selected AbstractsSingle photon fluorescent microlithography for live-cell imagingMICROSCOPY RESEARCH AND TECHNIQUE, Issue 1 2010Darío Kunik Abstract Using fluorescent dyes to trigger the polymerization of a commercial polyurethane resin allows a rapid fabrication of micrometer and submicrometer sized fluorescent structures by one-photon absorption. Here, we show that standard He,Ne lasers emitting at 632.8 nm can be used to start the photopolymerization and that very low laser power is required. This procedure allows the fabrication of fiduciary fluorescent references on standard glass coverslips, mica sheets, or gold-coated coverslips for laser scanning or standard fluorescent microscopy. The biocompatibility of the polymerized resin with cells in culture was tested by growing Xenopus melanophores and a standard laser scanning microscope was used to demonstrate that it is possible to use equipment readily available in several laboratories. We show that fluorescent structure with less than 10 nm in height may be used as references in fluorescence microscopy allowing a smooth environment for cell growth. Different dyes were tested and the conditions for one-photon polymerization were outlined. Microsc. Res. Tech. 2009. © 2009 Wiley-Liss, Inc. [source] Acrosome reaction: methods for detection and clinical significanceANDROLOGIA, Issue 6 2000T. Zeginiadou The present article reviews the methods for detection and the clinical significance of the acrosome reaction. The best method for the detection of the acrosome reaction is electron microscopy, but it is expensive and labour-intensive and therefore cannot be used routinely. The most widely used methods utilize optical microscopy where spermatozoa are stained for the visualization of their acrosomal status. Different dyes are used for this purpose as well as lectins and antibodies labelled with fluorescence. The acrosome reaction following ionophore challenge (ARIC) can separate spermatozoa that undergo spontaneous acrosome reaction from those that are induced, making the result of the inducible acrosome reaction more meaningful. Many different stimuli have been used for the induction of the acrosome reaction with different results. The ARIC test can provide information on the fertilizing capability of a sample. The ARIC test was also used to evaluate patients undergoing in vitro fertilization since a low percentage of induced acrosome reaction was found to be associated with lower rates of fertilization. The cut-off value that could be used to identify infertile patients is under debate. Therapeutic decisions can also be made on the basis of the value of the ARIC test. [source] A Graphene Nanoprobe for Rapid, Sensitive, and Multicolor Fluorescent DNA AnalysisADVANCED FUNCTIONAL MATERIALS, Issue 3 2010Shijiang He Abstract Coupling nanomaterials with biomolecular recognition events represents a new direction in nanotechnology toward the development of novel molecular diagnostic tools. Here a graphene oxide (GO)-based multicolor fluorescent DNA nanoprobe that allows rapid, sensitive, and selective detection of DNA targets in homogeneous solution by exploiting interactions between GO and DNA molecules is reported. Because of the extraordinarily high quenching efficiency of GO, the fluorescent ssDNA probe exhibits minimal background fluorescence, while strong emission is observed when it forms a double helix with the specific targets, leading to a high signal-to-background ratio. Importantly, the large planar surface of GO allows simultaneous quenching of multiple DNA probes labeled with different dyes, leading to a multicolor sensor for the detection of multiple DNA targets in the same solution. It is also demonstrated that this GO-based sensing platform is suitable for the detection of a range of analytes when complemented with the use of functional DNA structures. [source] Microcontact Transfer Printing of Zeolite MonolayersADVANCED MATERIALS, Issue 10-11 2009Fabio Cucinotta A simple nonchemical functionalization method for transferring and patterning zeolite monolayers is described. Polarization experiments show that zeolite monolayers filled with two different dyes lead to different emission colors. [source] Rodenticide grain bait ingredient acceptance by Norway rats (Rattus norvegicus), California ground squirrels (Spermophilus beecheyi) and pocket gophers (Thomomys bottae)PEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 7 2006Terrell P Salmon Abstract Vertebrate pest control in California is often accomplished through the use of rodenticide grain baits. These grain baits are composed of steam-rolled oats (SRO), a toxicant, an indicator dye and an oil combination. A series of tests were performed to determine the effects of various dye and oil formulations on acceptance of grain bait by Norway rats [Rattus norvegicus (Berk)], California ground squirrels [Spermophilus beecheyi (Richardson)] and pocket gophers (Thomomys bottae Eyd & Gerv). Seven different dyes, four oil formulations and clean (untreated) oats were tested for acceptance. The addition of the selected oils and dyes to grain resulted in no significant differences in consumption. This indicates that there is a wide variety of dyes that could be used in the formulation of rodenticides. These alternatives could aid in proper pesticide use, the deterrence of bait consumption by birds and possibly in ingredient adhesion to the finished bait. Copyright © 2006 Society of Chemical Industry [source] Plasma proteomics of lung cancer by a linkage of multi-dimensional liquid chromatography and two-dimensional difference gel electrophoresisPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 13 2006Tetsuya Okano Abstract To investigate aberrant plasma proteins in lung cancer, we compared the proteomic profiles of serum from five lung cancer patients and from four healthy volunteers. Immuno-affinity chromatography was used to deplete highly abundant plasma proteins, and the resulting plasma samples were separated into eight fractions by anion-exchange chromatography. Quantitative protein profiles of the fractionated samples were generated by two-dimensional difference gel electrophoresis, in which the experimental samples and the internal control samples were labeled with different dyes and co-separated by two-dimensional polyacrylamide gel electrophoresis. This approach succeeded in resolving 3890 protein spots. For 364 of the protein spots, the expression level in lung cancer was more than twofold different from that in the healthy volunteers. These differences were statistically significant (Student's t -test, p -value less than 0.05). Mass spectrometric protein identification revealed that the 364 protein spots corresponded to 58 gene products, including the classical plasma proteins and the tissue-leakage proteins catalase, clusterin, ficolin, gelsolin, lumican, tetranectin, triosephosphate isomerase and vitronectin. The combination of multi-dimensional liquid chromatography and two-dimensional difference gel electrophoresis provides a valuable tool for serum proteomics in lung cancer. [source] Surface-directed assembly of cell-laden microgels,,BIOTECHNOLOGY & BIOENGINEERING, Issue 3 2010Yanan Du Abstract Cell-laden microscale hydrogels (microgels) can be used as tissue building blocks and assembled to create 3D tissue constructs with well-defined microarchitecture. In this article, we present a bottom-up approach to achieve microgel assembly on a patterned surface. Driven by surface tension, the hydrophilic microgels can be assembled into well-defined shapes on a glass surface patterned with hydrophobic and hydrophilic regions. We found that the cuboidic microgels (,100,200,µm in width) could self-assemble into defined shapes with high fidelity to the surface patterns. The microgel assembly process was improved by increasing the hydrophilicity of the microgels and reducing the surface tension of the surrounding solution. The assembled microgels were stabilized by a secondary crosslinking step. Assembled microgels containing cells stained with different dyes were fabricated to demonstrate the application of this approach for engineering microscale tissue constructs containing multiple cell types. This bottom-up approach enables rapid fabrication of cell-laden microgel assemblies with pre-defined geometrical and biological features, which is easily scalable and can be potentially used in microscale tissue engineering applications. Biotechnol. Bioeng. 2010; 105: 655,662. © 2009 Wiley Periodicals, Inc. [source] Photofading of azo dyes: a theoretical studyCOLORATION TECHNOLOGY, Issue 3 2008Sandeep Tripathi The light fastness of a number of azo dyes has been investigated using all-valence molecular orbital methods, AM1 and PM3. The results of molecular orbital calculations are used to obtain both highest occupied molecular orbital and lowest unoccupied molecular orbital frontier electron density, which, respectively, can account for the propensity of the electrophilic and nucleophilic attack at a particular atom in a molecule. The highest occupied molecular orbital and lowest unoccupied molecular orbital superdelocalisability have also been obtained to explain the order of light fastness values in different dyes of a particular series. In addition, attempts have been made to correlate the light fastness values with the difference in energy of the highest occupied molecular orbital of the dye and the lowest unoccupied molecular orbital of the singlet oxygen. [source] | ||||||||||||||||