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Suitable Probes (suitable + probe)
Selected AbstractsTracing of intracellular zinc(II) fluorescence flux to monitor cell apoptosis by using FluoZin-3AMCELL BIOCHEMISTRY AND FUNCTION, Issue 7 2009Yi-Ming Li Abstract Changes in the free zinc(II) concentration are closely related to cell proliferation and apoptosis, especially during the early apoptotic process. In the present paper, we demonstrated that zinc(II) probe FluoZin-3AM owns sensitive properties to distinguish different stages of apoptotic cell (induced by an anticancer agent, etoposide) according to trace intracellular zinc(II) fluorescence flux. When apoptosis in HeLa or K562 cells was artificially induced, FluoZin-3AM selectively and strongly stained apoptotic cells only at early and middle stages, which was attributed to significantly increased free zinc(II) flux during these stages. This conclusion was further verified by comparing it with the conventional apoptosis detector probe Annexin-V-FITC and PI. Furthermore, FluoZin-3AM was found cell permeable to detect the intracellular zinc(II) fluorescence enhancement to threefolds within 120,s with low cytotoxicity when zinc(II) was incorporated into the cell by zinc(II) ionophore pyrithione. All the above implied that monitoring intracellular zinc fluorescence flux was an effective method to distinguish cell apoptosis from necrosis, and FluoZin-3AM was found to be a suitable probe acting alone to fulfill the work. Copyright © 2009 John Wiley & Sons, Ltd. [source] Development and experimental validation of a nifH oligonucleotide microarray to study diazotrophic communities in a glacier forefieldENVIRONMENTAL MICROBIOLOGY, Issue 8 2009Laurence Duc Summary Functional microarrays are powerful tools that allow the parallel detection of multiple strains at the species level and therefore to rapidly obtain information on microbial communities in the environment. However, the design of suitable probes is prone to uncertainties, as it is based so far on in silico predictions including weighted mismatch number and Gibbs free-energy values. This study describes the experimental selection of probes targeting subsequences of the nifH gene to study the community structure of diazotrophic populations present in Damma glacier (Swiss Central Alps) forefield soils. Using the Geniom® One in situ synthesis technology (Febit, Germany), 2727 in silico designed candidate probes were tested. A total of 946 specific probes were selected and validated. This probe set covered a large diversity of the NifH phylotypes (35 out of the 45) found in the forefield. Hybridization predictors were tested statistically. Gibbs free-energy value for probe-target binding gave the best prediction for hybridization efficiency, while the weighted mismatch number was not significantly associated to probe specificity. In this study, we demonstrate that extensive experimental tests of probe-hybridization behaviour against sequences present in the studied environment remain a prerequisite for meaningful probe selection. [source] 2,4-Dioxa-7-aza-, 2,4-Dioxa-8-aza-, and 2,4-Dioxa-9-aza-3-phosphadecalins as Rigid Acetylcholine Mimetics: Syntheses and CharacterizationHELVETICA CHIMICA ACTA, Issue 10 2004Stefan Furegati Phosphorylation of suitable piperidine precursors yielded a series of novel decalin-type O,N,P-heterocycles. The title compounds, P(3)-axially and P(3)-equatorially X-substituted, cis- and trans- configurated 2,4-dioxa-7-aza-, 2,4-dioxa-8-aza-, and 2,4-dioxa-9-aza-3-phosphabicyclo[4.4.0]decane 3-oxides (X=Cl, F, 4-nitrophenoxy, and 2,4-dinitrophenoxy), are configuratively fixed and conformationally constrained P-analogues of acetylcholine and as such represent acetylcholine (7-aza and 9-aza isomers) or , -homo-acetylcholine mimetics (8-aza isomers). Being irreversible inhibitors of acetylcholinesterase (AChE), the compounds are considered to be suitable probes for the investigation of the stereochemical course of the inhibition reaction by 31P-NMR spectroscopy. Moreover, the design of these mimetics will enable studies of molecular interactions with AChE, in particular, the recognition conformation of acetylcholine. [source] Tracking bio-molecules in live cells using quantum dotsJOURNAL OF BIOPHOTONICS, Issue 4 2008Yun-Pei Chang Abstract Single particle tracking (SPT) techniques were developed to explore bio-molecules dynamics in live cells at single molecule sensitivity and nanometer spatial resolution. Recent developments in quantum dots (Qdots) surface coating and bio-conjugation schemes have made them most suitable probes for live cell applications. Here we review recent advancements in using quantum dots as SPT probes for live cell experiments. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] | ||||||||||