Detection Molecular Detection

Studies on the 16S rDNA gene have already given some interesting results either by differentiating V. vulnificus against other representatives of the Vibrio or by differentiating type B from type A strains, thus allowing an understanding of mixed infections and seasonal variation between strains.[29] Indirect study with PCR-DGGE showed sensitivity based on a pure culture of Escherichia coli of between 104 and 105 cfu/mL.[30] A study of the 16S-23S rDNA spacers highlighted the possibility of detecting NCBV strains in oysters,[31] demonstrating the value of such molecular methods to identify pathogens that will not grow on artificial media whatever species they are.

DNA probing the cth and tlh genes (hemolysin-related genes) allowed authors to differentiate V. vulnificus and V. parahaemolyticus, respectively.[32] However, polymorphism is still a major problem to find strain-specific or species-specific probes not cross-reacting with other vibrios.[33]

However, other authors tried to elucidate the gene regulations of V. vulnificus to develop new control methods. The haem uptake receptor R (hupR) was shown to share homologies with the LysR family and could be a positive regulator of hupA gene to satisfy V. vulnificus iron requirements.1-34-1

Several regions such as cytolysin, vvhA (V. vulnificus hemolysin gene), pR72H (a 0.76-kb Hindlll DNA fragment cloned from V. parahaemolyticus), and 16S-23S rRNA were simultaneously used to specifically identify this bacterium.[40] The vvhA gene responsible for the production of the cytolytic hemolysin of V. vulnificus and its activation by the cAMP receptor protein (CRP) has also been extensively studied.[35] Mutagenesis study of a virulent V. vulnificus strain identified four essential capsular polysaccharides (CPS) for virulence expression.[36] A seminested PCR on the vvhA gene showed its transcription in NCBV populations and may be very useful for assessment of water quality.[37]

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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