Detection of Hepatitis B Virus Polymerase Gene Variants Associated with Lamivudine, Adefovir and Entecavir Resistance and Some Undefined Mutations Isolated from Chronic Hepatitis B Patients in the South of Turkey

IIn order to detect the mutation patterns related to Lamivudine (LAM), Adefovir (ADV) and Entecavir (ETV) resistance, we examined totally 230 stored HBsAg (+) and HBV DNA (+) sera samples of patients suffering chronic hepatitis B and treated with LAM, ADV and ETV in the south of Turkey. 100, 110 and 20 sera wereobtained from patients treated with LAM (for at least 2 years), ADV (for at least 2 years) and ETV (for at least1 year), respectively. A 422 bp segment of HBV polymerase gene which included B, C and D domains of viral polymerase gene was amplified by a nested PCR protocol and sequenced by a silver staining based cyclesequencingreaction. Mutation patterns related to LAM, ADV and ETV resistance were detected in 23 of 100 (23.00%), 3 of110 (2.75 %) and 0 of 20 (0.00%) sera in 3 groups, respectively. rtM204I and rtM204VrtL180M dual mutationswere detected in 13 of 100 (13.00%) and 10 of 100 (10.00%) sera, respectively in LAM treated group. rtN236Tmutation was detected in 3 of 110 (2.75%) sera in ADV treated group. rtM204I and rtM204VrtL180M mutations were also detected in 8 of 110 (7.27%) and 5 of 110 (4.54%) sera in ADV treated group. No mutation pattern was detected related to ETV resistance. However, rtM204I mutation was also detected in 3 of 20 (15.00%)in ETV treated group. Additionally, some undefined mutations such as rtI233V, rtN238R, P237H and rtK241Ewere detected in 3 of 110 (2.75%), 2 of 110 (1.80%), 1 of 110 (0.90%) and 1 of 110 (0.90%) sera, respectively inADV treated group. The study reveals that detection of mutations associated with viral polymerase inhibitors isimportant for better patient treatment. Antiviral therapy of hepatitis with viral polymerase inhibitors is still controversial.IIn order to detect the mutation patterns related to Lamivudine (LAM), Adefovir (ADV) and Entecavir (ETV) resistance, we examined totally 230 stored HBsAg (+) and HBV DNA (+) sera samples of patients suffering chronic hepatitis B and treated with LAM, ADV and ETV in the south of Turkey. 100, 110 and 20 sera wereobtained from patients treated with LAM (for at least 2 years), ADV (for at least 2 years) and ETV (for at least1 year), respectively. A 422 bp segment of HBV polymerase gene which included B, C and D domains of viral polymerase gene was amplified by a nested PCR protocol and sequenced by a silver staining based cyclesequencingreaction. Mutation patterns related to LAM, ADV and ETV resistance were detected in 23 of 100 (23.00%), 3 of110 (2.75 %) and 0 of 20 (0.00%) sera in 3 groups, respectively. rtM204I and rtM204VrtL180M dual mutationswere detected in 13 of 100 (13.00%) and 10 of 100 (10.00%) sera, respectively in LAM treated group. rtN236Tmutation was detected in 3 of 110 (2.75%) sera in ADV treated group. rtM204I and rtM204VrtL180M mutations were also detected in 8 of 110 (7.27%) and 5 of 110 (4.54%) sera in ADV treated group. No mutation pattern was detected related to ETV resistance. However, rtM204I mutation was also detected in 3 of 20 (15.00%)in ETV treated group. Additionally, some undefined mutations such as rtI233V, rtN238R, P237H and rtK241Ewere detected in 3 of 110 (2.75%), 2 of 110 (1.80%), 1 of 110 (0.90%) and 1 of 110 (0.90%) sera, respectively inADV treated group. The study reveals that detection of mutations associated with viral polymerase inhibitors isimportant for better patient treatment. Antiviral therapy of hepatitis with viral polymerase inhibitors is still controversial.</p

Evaluation of the Efficacy of 2% Chlorhexidine in Combination with Passive Ultrasonic Irrigation on Enterococcus faecalis Biofilm

Objective: This study aimed to evaluate the combined effectiveness of 2% chlorhexidine (CHX) and passive ultrasonic irrigation (PUI) against Enterococcus faecalis (E. faecalis) biofilm

Amplicon-based next-generation sequencing for comparative analysis of root canal microbiome of teeth with primary and persistent/secondary endodontic infections

© 2023, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.Objectives: To compare the root canal microbiome profiles of primary and persistent/secondary infections using high-throughput sequencing with the help of a reliable bioinformatics algorithm. Materials and methods: Root canal samples of 10 teeth in the primary endodontic infection (PEI) group and 10 teeth in the persistent/secondary endodontic infection (SEI) group were included resulting in a total of 20 samples. After DNA extraction from the samples, sequencing was performed on the Illumina MiSeq platform. Pair-end Illumina reads were imported to QIIME 2; amplicon sequence variants (ASVs) generated by DADA2 were mapped to GreenGenes database. Weighted UniFrac distances were calculated and principal coordinates analysis (PCoA) was used to compare beta diversity patterns. The multiple response permutation procedure (MRPP), the analysis of similarities (ANOSIM), and permutational multivariate analysis of variance (adonis) were conducted for testing group differences. Linear discriminant analysis effect size (LEfSe) analysis was utilized to identify differentially abundant taxa between the groups. The linear discriminant analysis (LDA) score threshold was set to 4.0. Results: Within the Gram-negative facultative anaerobic Gammaproteobacteria class outgroup, two orders (Pasteurellales, Vibrionales) and two families (Pasteurellaceae, Vibrionaceae) were significantly more abundant in the PEI group, whereas Gram-positive bacteria, Actinomycetales order, and Gram-positive anaerobic taxa, one genus (Olsenella) and one species (Olsenella uli), were identified as significantly more abundant in the SEI group. Conclusions: A few taxa were differentially abundant within either the PEI or SEI group. Clinical relevance: Reliable bioinformatic tools are needed to define microbial profiles of endodontic infections. Based on a limited number of samples, no distinct variation was determined between the bacterial diversity of initial and recurrent endodontic infections