Typhoid fever and paratyphoid fevers are still serious public health problems in many developing countries and are endemic in many countries, especially in Southeast Asia and Africa. Typhoid and paratyphoid fever are sometimes fatal infections of adults and children, with bacteremia and inflammatory destruction of the intestine and other organs. They require urgent treatment by the administration of appropriate antibiotics. Recently, fluo-roquinolone-resistant and nalidixic acid-resistant strains of S. Typhi and S. Paratyphi A have emerged in the Indian subcontinent, becoming problematic in many other countries.[18,19] Fluoroquinolone resistance has been associated with mutations in gyrA and parC, which encode DNA gyrase and topoisomerase IV, respectively. Particularly in Enterobacteriaceae, gyrA mutations contribute greatly to fluoroquinolone resistance.1-20-1 The product of the gyrA gene, DNA gyrase, is thought to be a target of fluoroquinolones. gyrA mutations lead to conformational changes in DNA gyrase and cause fluoroquinolone resistance. Mutations at codon 83 and/ or 87 of gyrA have been associated with fluoroquinolone resistance in Salmonella spp. Screening methods for antimicrobial resistance genes are also being developed by PCR. Screening methods for gyrA mutations giving fluoroquinolone resistance by PCR-restriction fragment length polymorphism (RFLP) have been developed and have been reported for S. Typhimurium, S. Typhi, and S. Paratyphi A. PCR-RFLP seems to be one of the best methods for the rapid detection of gyrA mutations.
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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.