ABSTRACT
BACKGROUND: Polymerase-chain reaction (PCR) detection is useful to diagnosis of pertussis at initial stage because the growth rate of Bordetella pertussis (B. pertussis) is relatively slow. Currently, the primer set for the insertion sequence IS481 (BP primer) is used widely for PCR detection of B. pertussis. However, the cross-reactivity of BP primer set with Bordetella holmesii (B. holmesii) was reported recently. Therefore, discrimination of B. pertussis and B. holmesii is needed in PCR step. For this reason, we developed new primer sets based on 16S rDNA sequence for diagnostic use and estimated the efficiency of these new primer sets. MATERIALS AND METHODS: The specific PCR primers were designed from the aligned sequence matrix of 16S rDNA genes of various Bordetella species. The specificity of designed primers were estimated using clinically important 4 Bordetella species, B. pertussis, B. holmesii, Bordetella parapertussis (B. parapertussis) and Bordetella bronchiseptica (B. bronchiseptica). The sensitivity to B. pertussis of designed primers was also estimated and compared with BP primer set. RESULTS: As the results, the developed new primer set successfully distinguished B. pertussis and other Bordetella species containing B. holmesii. In the sensitivity assay, the detectable limits of 16S-F2/16S-R1 primer set for B. pertussis were revealed as 5 pg of genomic DNA and 105 cells/mL of cell suspension. In addition to these, identical results between BP with primer and new primer were obtained in clinical samples. CONCLUSION: In this study, the specific primer set for B. pertussis was developed based on 16S rDNA sequence and this primer set did not show cross-reactivity to B. holmesii. In addition to these, the applicability of this primer set to the clinical specimens was also confirmed.
Subject(s)
Bordetella , Bordetella bronchiseptica , Bordetella parapertussis , Bordetella pertussis , Discrimination, Psychological , DNA , DNA, Ribosomal , Polymerase Chain Reaction , Sensitivity and Specificity , Whooping CoughABSTRACT
BACKGROUND: Polymerase-chain reaction (PCR) detection is useful to diagnosis of pertussis at initial stage because the growth rate of Bordetella pertussis (B. pertussis) is relatively slow. Currently, the primer set for the insertion sequence IS481 (BP primer) is used widely for PCR detection of B. pertussis. However, the cross-reactivity of BP primer set with Bordetella holmesii (B. holmesii) was reported recently. Therefore, discrimination of B. pertussis and B. holmesii is needed in PCR step. For this reason, we developed new primer sets based on 16S rDNA sequence for diagnostic use and estimated the efficiency of these new primer sets. MATERIALS AND METHODS: The specific PCR primers were designed from the aligned sequence matrix of 16S rDNA genes of various Bordetella species. The specificity of designed primers were estimated using clinically important 4 Bordetella species, B. pertussis, B. holmesii, Bordetella parapertussis (B. parapertussis) and Bordetella bronchiseptica (B. bronchiseptica). The sensitivity to B. pertussis of designed primers was also estimated and compared with BP primer set. RESULTS: As the results, the developed new primer set successfully distinguished B. pertussis and other Bordetella species containing B. holmesii. In the sensitivity assay, the detectable limits of 16S-F2/16S-R1 primer set for B. pertussis were revealed as 5 pg of genomic DNA and 105 cells/mL of cell suspension. In addition to these, identical results between BP with primer and new primer were obtained in clinical samples. CONCLUSION: In this study, the specific primer set for B. pertussis was developed based on 16S rDNA sequence and this primer set did not show cross-reactivity to B. holmesii. In addition to these, the applicability of this primer set to the clinical specimens was also confirmed.
Subject(s)
Bordetella , Bordetella bronchiseptica , Bordetella parapertussis , Bordetella pertussis , Discrimination, Psychological , DNA , DNA, Ribosomal , Polymerase Chain Reaction , Sensitivity and Specificity , Whooping CoughABSTRACT
BACKGROUND/AIMS: Adefovir dipivoxil is effective in patients with lamivudine-resistant hepatitis B virus (HBV). However, little is known about its role in Korean patients with decompensated liver cirrhosis. We retrospectively evaluated the efficacy and safety of adefovir dipivoxil in patients with decompensated liver cirrhosis with lamivudine resistance, and we compared this to the patients having compensated liver disease. METHODS: The patients with lamivudine-resistant chronic liver disease were enrolled and they received adefovir dipivoxil 10 mg daily. The clinical course and the biochemical and virological response of the decompensated cirrhosis group were compared with those of the patients with compensated liver disease group. RESULTS: One-hundred and one patients (the decompensated cirrhosis group, n=53; the compensated liver disease group, n=48) were evaluated. During the following up, 13 patients in the decompensated group and 4 patients in the compensated group dropped out of the treatment (P=0.011). After adefovir treatment, the proportion of patients with serum HBV DNA below 0.5 pg/mL in the decompensated group was less than that in the compensated group (50.9% vs. 83.3%, P=0.001), but the rates of normalized ALT, HBeAg loss and HBeAg seroconversion did not differ. The change of the Child-Pugh score in the decompensated group was 9.1 +/- 1.8 to 6.9 +/- 1.6 (P<0.001). The biochemical response in decompensated group was slower than that in the compensated group. Renal toxicity was not observed in either group. CONCLUSIONS: These results suggest that adefovir dipivoxil would be an effective and safe treatment for patients with decompensated liver cirrhosis with lamivudine resistance, but its effect might be limited and slower for decompensated cirrhosis.