NonPCRBased Method

The possibility of detecting clarithromycin resistance without performing PCR also exists, by fluorescence in situ hybridization (FISH). This method has been applied to the detection of H. pylori and its clarithromycin resistance by Trebesius et al.[23] It consists of an rRNA-based whole cell in situ hybridization using a set of fluorescent labeled oligonucleotide probes. Labeling of intact single bacteria is monitored by fluorescence microscopy. This method allows the detection of H. pylori with a 16S rRNA probe labeled with the fluorochrome Cy3 (red) and of resistant mutants with a 23S rRNA probe labeled with fluorescein (green) simultaneously. This method proved to be sensitive and specific when compared to standard methods of culture and susceptibility testing. No discrepant result was noted for 45 cases. In another study, there were 11 discrepant results among 69 cases. These cases corresponded indeed to mixed infections with susceptible and resistant strains. This method has the advantage of being independent of a nucleic acid preparation, it is not prone to inhibition like PCR and is quick. It also allows visualization of the bacteria including coccoidal forms and can be performed on paraffin embedded biopsy samples. A limitation could be the observer-dependent result and sometimes difficulty in reading. It has not been compared yet to the FRET-MCA protocol.

These new methods which provide a result within a few hours are very important for clinical practice because they have the potential to change the management of H. pylori infection; indeed, to administer, as a first line therapy, a regimen without clarithromycin in case of clarithromycin resistance instead of an empirical treatment in areas with high levels of this resistance and then to improve the eradication rate.

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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