H

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Fig. 1 M-FISH capture and analysis. Each fluorescent channel (A-E) and DAPI (F) is captured separately. Dedicated software processes each of these raw images to produce both a merged (H) and pseudo-color (I) composite. Each cell can be analyzed in detail by exploiting the individual images (A-J). This example shows a complex exchange in a human bone marrow CD34+ cell exposed in vitro to a-particle irradiation ( ~ 1 a-particle/cell). Chromosomes 1;5;14;16;17;22 have repaired as a single complex exchange, plus a deletion in 4p and a frag(4) can be seen. (View this art in color at www.dekker.com.)

obvious changes in centromere position or size of chromosome. In addition, depending on the fluorophore combination of chromosomes involved in an exchange, false colors can be produced at the junction as a consequence of flaring, resulting in the suggestion of an additional insertion. Technically though, it is possible to minimize such misclassification through the virtue that m-FISH compiles its pseudoimage via multiple captures. Before describing this in more detail, it is relevant to note that m-FISH is currently being applied for the successful analysis of radiation-induced chromosome aberrations where each of the damaged cells analyzed contains a unique abnormality.[4] Importantly, a number of different laboratories have verified the complexity of chromosome aberrations that can be detected at a single cell level using m-FISH, typically using cells of a similar quality and chromosome length to that seen in tumors.

The procedure of detailed (single-cell) m-FISH analysis is as follows: the DAPI raw image is examined allowing centromere and/or chromosome number to be counted and chromatid-type aberrations (relevant in ongoing genomic instability) to be scored. The chromosomes are karyotyped as enhanced DAPI, and obvious changes in banding pattern, especially involving intrachromosomal or homologous events, are noted. Each fluorescent channel is then assessed in turn looking for discontinuities in color down the length of the chromosomes, before, finally, the composite m-FISH image is assessed. Consequently, because the relative position of observed color junction breakpoints for each fluor is determined separately, the chance of bias from information displayed in the final pseudoimage is limited.

At a minimum, hardware consisting of a fluorescence microscope capable of holding six different epifluores-cence filter cubes, camera, and a computer platform that supports dedicated software is required. Overall therefore, irrespective of whether the m-FISH multiplex probe sets are developed locally or obtained commercially, the establishment of an m-FISH facility does represent a significant investment.

Getting Started With Dumbbells

Getting Started With Dumbbells

The use of dumbbells gives you a much more comprehensive strengthening effect because the workout engages your stabilizer muscles, in addition to the muscle you may be pin-pointing. Without all of the belts and artificial stabilizers of a machine, you also engage your core muscles, which are your body's natural stabilizers.

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