ABSTRACT
OBJECTIVES: Detection of mutations associated to nucleos(t)ide analogs and hepatitis B virus (HBV) genotyping are essential for monitoring treatment of HBV infection. We developed a multiplex polymerase chain reaction-ligase detection reaction (PCR-LDR) assay for the rapid detection of HBV genotypes and mutations associated with lamivudine, adefovir, and telbivudine resistance in HBV-infected patients. METHODS: HBV templates were amplified by PCR, followed by LDR and electrophoresis on a sequencer. The assay was evaluated using plasmids that contained wild-type or mutant HBV sequences and 216 clinical samples. RESULTS: The PCR-LDR assay and sequencing gave comparable results for 158 of the 216 samples (73.1 percent) with respect to mutation detection and genotyping. Complete agreement between the two methods was observed for all the samples (100 percent) at codon 180 and codon 204. Concordant results were observed for 99.4 percent of the 158 samples at codon 181 and 98.7 percent at codon 236. The genotyping results were completely concordant between the PCR-LDR assay and sequencing. The PCR-LDR assay could detect a proportion of 1 percent mutant plasmid in a background of wild-type plasmid. CONCLUSION: The PCR-LDR assay is sensitive and specific for detection of HBV genotypes and drug resistance mutations, and could be helpful for decision making in the treatment of HBV infection.
Subject(s)
Humans , Adenine/analogs & derivatives , Antiviral Agents/pharmacology , Drug Resistance, Multiple, Viral/genetics , Hepatitis B virus/drug effects , Lamivudine/pharmacology , Mutation/genetics , Nucleosides/pharmacology , Phosphorous Acids , Pyrimidinones/pharmacology , Adenine/pharmacology , DNA, Viral/genetics , Genotype , Hepatitis B virus/genetics , Hepatitis B/virology , Ligase Chain Reaction , Microbial Sensitivity Tests , Multiplex Polymerase Chain ReactionABSTRACT
To investigate the longitudinal sagittal growth changes of maxilla and mandible according to the quantitative cervical vertebral maturation (QCVM) for adolescents with normal occlusion,mixed longitudinal data were used.The samples included 87 adolescents aged from 8 to 18 y old with normal occlusion (32 males,55 females) selected from 901 candidates.Sequential lateral cephalograms and hand-wrist films were taken once a year,lasting for 6 y.The longitudinal sagittal growth changes of maxilla and mandible according to QCVM were measured.There were some significant differences between maxilla and mandible according to QCVM.The sagittal growth change of maxilla showed a trend towards high velocity→decelerating velocity→completing velocity from QCVM stage Ⅰ to stage Ⅳ.The sagittal growth change of mandible showed a trend towards accelerating velocity→high velocity→decelerating velocity→completing velocity from QCVM stage Ⅰ to stage IV.With sagittal relationship,growth magnitude was almost the same between maxilla and mandible at QCVM stage Ⅰ.At stage Ⅱ the growth of mandible exceeded that of maxilla and growth in mandible continued at stages Ⅲ and Ⅳ,while the maxilla ceased to grow.Growth magnitude was greater and the growth duration was longer with male mandible.It is concluded that the longitudinal sagittal growth changes of maxilla and mandible on the basis of QCVM is of value in the orthodontic practice.