Concentration effects on the local structures and electronic properties of ErxBaY2-xF8: a first-principles study.

Er3+doped barium yttrium fluoride (BaY2F8) crystal has gained long-term attention due to its great potential in laser and medical device applications. However, the local structures of Er3+doped BaY2F8system (Er:BYF) remain uncertain, and the effect of doping concentration on structures and properties is unknown. Therefore, in this study, the first-principles study of the structural evolution of ErxBaY2-xF8(x= 0.125, 0.25) crystals was carried out. By means of density functional theory and particle swarm optimization algorithm, the stable structures of Er:BYF crystals with two different concentrations are shown as standard monoclinic structures withP2 symmetry for the first time. The impurity Er3+ions successfully enter the main lattice, replacing the Y3+ions, and forming a [ErF8]5-polyhedron withC2point group symmetry. By calculating the electronic properties, the band gap values of the two structures are significantly reduced compared with that of pure BaY2F8crystal. However, the conduction band does not break through the Fermi level, and the crystals still maintain the insulation characteristic. According to the calculation of the electron local density function, we conclude that Er-F and Y-F in Er:BYF are connected by ionic bonds. These results fill a theoretical gap in the study of Er:BYF crystals and provide inspiration for structural evolution and material design at different doping concentrations.

Phytoecdysteroids from Dianthus superbus L.: Structures and anti-neuroinflammatory evaluation.

Six undescribed C27-phytoecdysteroid derivatives, named superecdysones A-F, and ten known analogs were extracted from the whole plant of Dianthus superbus L. Their structures were identified by extensive spectroscopy, mass spectrometric methods, chemical transformations, chiral HPLC analysis, and the single-crystal X-ray diffraction analysis. Superecdysones A and B possess a tetrahydrofuran ring in the side chain and superecdysones C-E are rare phytoecdysones containing a (R)-lactic acid moiety, whereas superecdysone F is an uncommon B-ring-modified ecdysone. Notably, based on the variable temperature (from 333 K to 253 K) NMR experiments of superecdysone C, the missing carbon signals were visible at 253 K and assigned. The neuroinflammatory bioassay of all compounds were evaluated, and 22-acetyl-2-deoxyecdysone, 2-deoxy-20-hydroxyecdysone, 20-hydroxyecdysone, ecdysterone-22-O-benzoate, 20-hydroxyecdysone-20,22-O-R-ethylidene, and acetonide derivative 20-hydroxyecdysterone-20, 22-acetonide significantly suppressed the LPS-induced nitric oxide generation in microglia cells (BV-2), with IC50 values ranging from 6.9 to 23.0 µM. Structure-activity relationships were also discussed. Molecular docking simulations of the active compounds confirmed the possible mechanism of action against neuroinflammations. Furthermore, none compounds showed cytotoxicity against HepG2 and MCF-7. It is the first report about the occurrence and anti-neuroinflammatory activity of the phytoecdysteroids in the genus Dianthus. Our findings demonstrated that ecdysteroids may be used as potential anti-inflammatory drugs.

Ozone Gas Bath Combined with Endovenous Laser Therapy for Lower Limb Venous Ulcers: A Randomized Clinical Trial.

BACKGROUND: Endovenous laser therapy (EVLT) is safe and effective for lower limb venous ulcers. However, severe necrosis and infection in the ulcer area are contraindications of puncture and EVLT. Local bath with ozone gas has been shown to improve the condition of ulcer areas. The aim of this study was to evaluate the clinical efficacy of ozone gas bath combined with EVLT in comparison with EVLT alone for the treatment for lower limb venous ulcers. PATIENTS AND METHODS: Ninety-two patients with venous ulcers were randomized to receive ozone gas bath combined with EVLT (OEVLT group) or EVLT alone (EVLT group). In the OEVLT group, the venous ulcers were preconditioned with ozone gas bath prior to EVLT. The minimum follow-up time was 12 months. The two groups were compared in terms of complete occlusion of the treated veins, ulcer healing ratio, ratio of ulcer recurrence, patient satisfaction, complications, and side effects. RESULTS: There was no significant difference in venous occlusion between the two groups. The ratio of ulcer healing in the OEVLT group was significantly higher than the EVLT group at 12 months follow-up. Patients in the OEVLT group showed better satisfaction and a lower recurrence ratio than the OEVLT group. No severe complications or side effects occurred in either groups. CONCLUSIONS: Ozone gas bath combined with EVLT showed improved efficacy for the treatment of lower limb venous ulcers and lower recurrence ratio comparison with EVLT alone. This procedure is a safe and technically feasible.