Medicinal herbs, especially Hibiscus sabdariffa, inhibit oral pathogenic bacteria.

OBJECTIVES: Medicinal herbs are plants with potential medicinal and health benefits. In recent years, they are being increasingly used as a treatment alternative owing to their effectiveness against various diseases. In this study, we investigated the inhibitory effects of 15 medicinal herbs on causative bacteria for dental caries and periodontal disease. METHODS: This study evaluated the effects of the extracts of 15 medicinal herbs on growth and biofilm formation in five oral pathogenic bacterial strains. The herbs were processed into extracts, and bacterial strains were cultured. Then, bacterial growth and biofilm formation were assessed using various methods. Finally, the extract of the herb Hibiscus sabdariffa (hibiscus) was analyzed using high-performance liquid chromatography. RESULTS: Incubation of bacteria with the herbal extracts showed that hibiscus exerted a significant inhibitory effect on all the oral pathogenic bacterial strains evaluated in this study. In addition, the pigment delphinidin-3-sambubioside, which is found in hibiscus extract, was identified as a particularly important inhibitory component. CONCLUSIONS: These results lay the ground work for the potential development of novel therapeutic or preventive agents against dental caries and periodontal disease, two major oral diseases.

Association between Intraoperative Early Warning Score and Mortality and In-Hospital Stay in Lower Gastrointestinal Spontaneous Perforation.

Background: Early warning scores (EWSs) can be easily calculated from physiological indices; however, the extent to which intraoperative EWSs and the corresponding changes are associated with patient prognosis is unknown. In this study, we investigated whether EWS and the corresponding time-related changes are associated with patient outcomes during the anesthetic management of lower gastrointestinal perforation. Methods: This was a single-center, retrospective cohort study conducted at a tertiary emergency care center. Adult patients who underwent surgery for spontaneous lower gastrointestinal perforations between September 1, 2012, and December 31, 2019, were included. The National Early Warning Score (NEWS) and Modified Early Warning Score (MEWS) were calculated based on the intraoperative physiological indices, and the associations with in-hospital death and length of hospital stay were investigated. Results: A total of 101 patients were analyzed. The median age was 70 years, and there were 11 cases of in-hospital death (mortality rate: 10.9%). There was a significant association between the intraoperative maximum NEWS and in-hospital death (odds ratio (OR): 1.60, 95% confidence interval (CI): 1.10-2.32, p=0.013) and change from initial to maximum NEWS (OR: 1.60, 95% CI: 1.07-2.40, p=0.023) in the crude analysis. However, when adjustments were made for confounding factors, no statistically significant associations were found. Other intraoperative EWS values and changes were not significantly associated with the investigated outcomes. The preoperative sepsis-related organ failure assessment score and the intraoperative base excess value were significantly associated with in-hospital death. Conclusions: No clear association was observed between EWSs and corresponding changes and in-hospital death in cases of lower gastrointestinal perforation. The preoperative sepsis-related organ failure assessment score and intraoperative base excess value were significantly associated with in-hospital death.

Structure and dissolution of silicophosphate glass.

P2O5-SiO2-Na2O-CaO glasses are promising therapeutic ion-releasing materials. Herein, we investigated the state of silicon (Si) in P2O5-SiO2-Na2O-CaO glass using a model with a composition of 55.0P2O5-21.3SiO2-23.7Na2O (mol%), incorporating a six-fold-coordinated silicon structure ([6]Si). The model was constructed using a classical molecular dynamics method and relaxed using the first-principles method. Further, we experimentally prepared glasses, substituting Na2O for CaO, to investigate the dissolution of glass with varying [6]Si and PO4 tetrahedra (Q P n ) distributions (n = number of bridging oxygens (BOs) to neighboring tetrahedra). [6]Si in the glass model preferentially coordinated with Q P 3. When Si was surrounded by phosphate groups, phosphorus (P) induced the formation of [6]Si by elongating the Si-O distance, and [6]Si acted like a glass network former (NWF). Na+ coordinated with [6]Si-O-P bonds via electrostatic interactions with BO. 31P and 29Si magic-angle-spinning-nuclear-magnetic-resonance spectra of three experimental glass samples with the compositions of 55.0P2O5-21.3SiO2-xCaO-(23.7 - x)Na2O (mol%, x = 0, 12.4, and 23.7) showed that Q P 3 and [6]Si increased with increasing Na2O. When each glass powder was immersed in a tris-HCl buffer solution at 37 °C, the dissolution of NWF ions and network modifier (NWM) ions increased almost monotonically with time for all samples, indicating that the solubility of the samples was suppressed by the coexistence of CaO and Na2O, attributed to the delocalization of the electron distribution of P in the [6]Si-coordinated Q P 3 units compared to that in the P- or [4]Si-coordinated Q P 3 units, which reduces hydrolysis.

Diffusion of protons and sodium ions in silicophosphate glasses: insight based on first-principles molecular dynamic simulations.

We propose a microscopic diffusion mechanism of protons and Na+ ions in phosphate glasses using first-principles molecular dynamic simulations. Protons hop and are chemisorbed onto non-bridging oxygen (NBO) of nearby PO4 tetrahedra through hydrogen bonds. The subsequent behavior depends on the morphology of the PO4 tetrahedra (QnP values). When a proton is adsorbed onto the NBO of a Q3P unit, it is desorbed on a short time scale of within 10 fs and re-adsorbed onto the NBO that was previously adsorbed. However, when a proton is adsorbed onto the NBO of a Q2P unit, another proton coordinated before adsorption is desorbed in a chain, resulting in the diffusion of protons. When a Na+ ion is present in the vicinity, the adsorption of a proton onto a Q2P unit leads to a decrease in the electrostatic interaction between Na+ and O- ions and induces the diffusion of Na+ ions. We conclude that the difference in the morphology of PO4 tetrahedra greatly affects the diffusion of protons and Na+ ions.