Analytical sensitivities and specificities of the assays

In general, the sensitivities of HPV typing assays are dependent on the reaction that precedes the typing step. The sensitivity of the only nonamplification technique described in this article, the HC2 method, is 5000 copies of the HPV genome per reaction well according to the manufacturer. All other methods described here consist of a PCR step followed by a typing step. These methods have a much higher analytical sensitivity than HC2, with a slight variation between the methods (reviewed in Ref. [18]). In general, less than 100 HPV genome equivalents in a reaction tube are sufficient to generate a positive PCR signal and to enable typing.

It is self-evident that specificities of the HPV typing assays rely on the specificities of the respective probes for their corresponding HPV types under the respective hybridization conditions. In addition, PCR-based methods depend on the specificity of the amplification primers.

As opposed to typing after consensus PCR, it is also possible to type during the reaction, in real time. Various real-time PCR techniques are available, the best known being molecular beacons, the fluorescent 5' exonuclease assay (e.g., TaqMan), and fluorescence energy resonance transfer assays (e.g., LightCycler).

At present, the only real-time assay that allows consensus HPV-PCR with simultaneous typing is a molecular beacons assay.[16] However, the multiplicity of this technique is limited because the current generation of real-time thermocyclers does not allow for more than six differentially labeled probes. Hence for typing of multiple HPV infections, reverse hybridization methods are preferred over real-time assays.

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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