48 research outputs found
Fungicidal Action of Hydroxyl Radicals Generated by Ultrasound in Water
It is well known that hydroxyl radicals are generated by ultrasound in water. This study with an electron spin resonance spin-trapping technique showed that hydroxyl radical generation was positively correlated with ultrasound duration and water temperature. The clear fungicidal action against Trichophyton spp. evident by studying cultured cells and the degradation of cytoplasmic and surface structures observed by transmission and scanning electron microscopy suggest that ultrasound in hot water is effective for sterilization of dermatophyte contamination and could be effective for the treatment of tinea infection
Continuous release of O2−/ONOO− in plasma-exposed HEPES-buffered saline promotes TRP channel-mediated uptake of a large cation
Although the externally controllable extracellular supply of the short-lived reactive oxygen and nitrogen species, such as O2•−, •NO, and ONOO−, could potentially manipulate cellular functions, their simple administration to cells is likely to be ineffective due to their rapid deactivation. In this study, we found a method of a continuous supply of O2•−/ONOO− over a few minutes, which is triggered by irradiation of a nonequilibrium atmospheric pressure plasma to commonly used organic buffers (e.g., 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid, HEPES). In addition, a continuous low-dose O2•−/ONOO− supply was shown to induce a physiologically relevant Ca2+ response and subsequently the uptake of a large cation mediated by transient receptor potential channel family member(s). Our results provide a novel approach to the continuous O2•−/ONOO− supply, requiring controllable and mass-volume treatments
Apatite-Forming Ability and Visible Light-Enhanced Antibacterial Activity of CuO-Supported TiO<sub>2</sub> Formed on Titanium by Chemical and Thermal Treatments
Titanium with apatite-forming ability as well as antibacterial activity is useful as a component of antibacterial dental implants. When Ti was subjected to hydrogen peroxide (H2O2), copper acetate (Cu(OAc)2), and heat (H2O2-Cu(OAc)2-heat) treatments, a network structure of anatase and rutile titanium dioxide (TiO2) and fine copper oxide (CuO) particles was formed on the Ti surface. The resulting samples accumulated a dense and uniform apatite layer on the surface when incubated in simulated body fluid and showed enhanced antibacterial activity against Escherichia coli and Staphylococcus aureus under visible-light irradiation. Electron spin resonance spectra of H2O2-Cu(OAc)2-heat-treated samples showed that hydroxyl radicals (·OH) were generated from the samples, and the concentration of ·OH increased with increasing Cu concentration of the Cu(OAc)2 solution. The enhanced antibacterial activity of these samples under visible-light irradiation may be attributable to the generation of ·OH from samples. These results suggest that Ti implants obtained using H2O2-Cu(OAc)2-heat treatments and subjected to regular or on-demand visible-light irradiation may provide a decreased risk of peri-implantitis
Cold atmospheric plasma enhances osteoblast differentiation.
This study was designed to assess the effects of cold atmospheric plasma on osteoblastic differentiation in pre-osteoblastic MC3T3-E1 cells. Plasma was irradiated directly to a culture medium containing plated cells for 5 s or 10 s. Alkaline phosphatase (ALP) activity assay and alizarin red staining were applied to assess osteoblastic differentiation. The plasma-generated radicals were detected directly using an electron spin resonance-spin trapping technique. Results show that plasma irradiation under specific conditions increased ALP activity and enhanced mineralization, and demonstrated that the yield of radicals was increased in an irradiation-time-dependent manner. Appropriate plasma irradiation stimulated the osteoblastic differentiation of the cells. This process offers the potential of promoting bone regeneration
Characteristic values of AEW obtained from 0.1% NaCl solution.
<p>Each value represents the mean of duplicate determinations.</p>*<p>Residual chlorine is consisted of combined available chlorine and free available chlorine.</p
ESR spectra of AEW prepared by triple electrolyses of 1% NaCl solution.
<p>Spectra in the absence and presence of HCOONa are shown.</p
ESR spectra of AEW prepared by single electrolysis of 1% NaCl solution.
<p>Spectra in the absence and presence of FeSO<sub>4</sub> are shown.</p