Improvements Of The Fish Technique

A number of recent developments have led to improvements in FISH technology. These include the development of several multicolor fluorescence techniques as well as comparative genomic hybridization (CGH), an approach that allows tumor genomes to be tested for the presence of chromosomal unbalances without the need of metaphases and only requires small numbers of tumor cells to prepare DNA.[11]

Multicolor FISH and SKY

One of the earliest limitations of FISH was the inability to distinguish more than one or two target sequences because of the limited number of fluorochromes available. The introduction of multicolor FISH (M-FISH) and spectral karyotype (SKY) allowed detecting chromosomal abnormalities in individuals with constitutional abnormalities and in tumor samples.[12-14] Simple and complex translocations and relatively large deletions are identified with ease. However, there are some limitations of karyotyping by multiplex FISH of painting probes. This technique is not useful in the detection of paracentric inversions, some pericentric inversions, insertions involving a single chromosome arm, small duplications, and small deletions. Some of the limitations mentioned above can be addressed by using FISH probes. Therefore multiplex FISH is strongest when used in a complementary manner with both conventional cytogenetic and FISH analysis.[15]

Several studies using SKY have shown its power in resolving the full spectrum of chromosome abnormalities in tumors, especially in complex karyotypes, as well as documenting new recurring rearrangements in lymphopro-liferative disorders.[16] However, SKY does not seem to be the election choice to detect hidden aberrations in normal karyotypes because only a low percentage of chromosomal abnormalities were detected by this technique. These results, and the fact that this is a laborious and expensive technique, suggest that SKY is not likely to have a clinical impact for the study of normal G-banding cases.

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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