Objective: The objective of this study is to determine the antimicrobial effects of MP, AV, and MP + AV in comparison with Ca(OH)2 against E. faecalis, as an intracanal medicament.
Materials and Methods: Antimicrobial activity of MP, AV, MP + AV, Ca(OH)2, and dimethyl sulfoxide was tested against E. faecalis using antimicrobial sensitivity testing, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC). The results were analyzed by Kruskal-Wallis test with Mann-Whitney post hoc test and repeated measures analysis of variance with Bonferroni post hoc test (P < 0.05).
Results: For agar well-diffusion method, MP + AV gave maximum inhibition zone diameter (mean: 8.11 ± 0.015 mm), MP (mean: 6.21 ± 0.046 mm, Ca(OH)2 (mean: 5.5 ± 0.006), and AV (mean: 5.05 ± 0.012) with P < 0.05. MIC for MP + AV was 2 mg/ml, MP at 8 mg/ml, Ca(OH)2 at 8 mg/ml, and AV at 16 mg/ml. The MBC for MP + AV is at 4 mg/ml, MP at 16 mg/ml, Ca(OH)2 at 16 mg/ml, and AV at 32 mg/ml.
Conclusion: The combination of MP and AV consistently showed better antimicrobial activity compared to MP and AV alone against E. faecalis. The findings suggest that MP and AV used in combination may be an ideal intracanal medicament in FET and PET.
METHODS: Bio-assay guided fractionation and subsequent isolation of compounds using open column chromatography. The antibacterial activity against gram positive and gram negative ATCC strain and resistant clinical strains were evaluated using microtiter broth dilution method to determine minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and time-kill assay. The chemical structure of the isolated compounds from the water fraction of the ethanol extract of leaves was elucidated using Nuclear Magnetic Resonance (NMR).
RESULTS: The ethanol extract of the leaves and barks showed antimicrobial activity against all four ATCC and eight clinical isolates. The ethanol extract of the leaves and the corresponding water fraction had good activity against MRSA S. aureus. (MIC: 250 μg/ml) and had bactericidal effect on eight of the clinical strains (MSSA,MRSA, oxacillin-resistant CONS, oxacillin-sensitive CONS, Enterococcus faecalis, Klebsiela species, Kleb pneumoniae ESBL and Candida parapsilosis). Further phytochemical investigation of the water fraction of the crude ethanol extract of leaves afforded compound 7 (hyperin) and compound 8 (cynaroside) that had bactericidal activity against tested bacterial species (MIC 50 μg/ml and 100 μg/ml). The two compounds were isolated from this genus for the first time.
CONCLUSIONS: These results may provide a rational support for the traditional use of Canarium patentinervium Miq. in infections and wound healing, since the antimicrobial compounds isolated were also present in the leaves extract.
METHODS: Comprehensive searches of the NCBI database were performed to identify published peer-reviewed articles and genomes of E. faecalis ST476. Each genome was analysed for resistome, virulome, OptrA variant and optrA genetic contexts. A phylogenetic comparison of ST476 genomes with publicly available genomes of other STs was also performed.
RESULTS: Sixty-six E. faecalis ST476 isolates from 15 countries (China, Japan, South Korea, Austria, Denmark, Spain, Czech Republic, Colombia, Tunisia, Italy, Malaysia, Belgium, Germany, United Arab Emirates and Switzerland) mainly of human and animal origin were identified. Thirty available ST476 genomes compared with genomes of 591 STs indicated a progressive radiation of E. faecalis STs starting from ST21. The closest ancestral node for ST476 was ST1238. Thirty E. faecalis ST476 genomes exhibited 3-916 SNP differences. Several antimicrobial resistance and virulence genes were conserved among the ST476 genomes. The optrA genetic context exhibited a high degree of or complete identity to the chromosomal transposon Tn6674. Only three isolates displayed an optrA-carrying plasmid with complete or partial Tn6674. The WT OptrA protein was most widespread in the ST476 lineage.
CONCLUSIONS: Linezolid-resistant optrA-carrying E. faecalis of the clonal lineage ST476 is globally distributed in human, animal and environmental settings. The presence of such an emerging clone can be of great concern for public health. Thus, a One Health approach is needed to counteract the spread and the evolution of this enterococcal clonal lineage.
METHODOLOGY: Dentin blocks were sterilized and E. faecalis and C. albicans microbial colonies were counted for colony-forming-units against 2%k21, 2%CHX and Ca(OH)2 medicaments. Biofilm colonies after 7 days on dentin were analysed using confocal laser scanning microscopy with live/dead bacterial viability staining. TEM was done to study dentin collagen matrix. Dentin discs from 3rd day and 7th day well plate was used for Raman spectra and observed under fluorescent-microscope. Docking studies were carried out on MMP-2 S1 binding-domain with k21.
RESULTS: There was reduction of E. faecalis/C. albicans when k21, chlorhexidine and calcium hydroxide were used with highest percentage in 2%k21 treated specimens. 2%k21 showed dense and regular collagen network with intact cross-banding and decreased Raman intensity for 2%k21 on 3rd day. NaOCl + k21 showed least adherence, whereas saline groups showed highest adherence of E. faecalis and C. albicans to root-canal dentin. Alizarin red staining of hDPSCs revealed calcium deposition in all groups with significant difference seen amongst 2%k21 groups. MMP-2 ligand binding was seen accurately indicating possible target sites for k21 intervention.
CONCLUSION: 2%k21 can be considered as alternative intracanal medicament.