We studied interactions of suspended cobalt ferrite nanoparticles and citric acid-adsorbed cobalt ferrite nanoparticles on membranes of giant phospholipid vesicles and erythrocytes. Citric acid adsorbed nanoparticles had larger impact on the number of giant phospholipid vesilces and erythrocyte shape than bare nanoparticles.
The purpose of the present study was to evaluate the influence of very low ambient illumination and complete darkness on the postural sway of young and elderly adults. Each participant performed four tests while standing on a force platform in the following conditions: in normal light (215 lx) with open eyes and with closed eyes, in very low illumination (0.25 lx) with open eyes, and in complete darkness with open eyes. Postural sway was assessed by means of the force platform measurements. Very low illumination resulted in a statistically significant increase in postural sway in both the young and elderly groups compared to normal light, although the increase was significantly smaller than those observed in the eyes closed and complete darkness condition, and no significant effects of illumination on fractal dimensions were detected. The gains of the sways in the very low or no illumination conditions relative to the normal light condition were significantly larger in the group of young participants than in the group of elderly participants (up to 50% and 25%, respectively). However, the response patterns to changes in illumination were similar in the young and elderly participants, with the exception of the short-range fractal dimension of the medio-lateral sway. In conclusion, very low illumination resulted in increased postural sway compared to normal illumination; however, in the closed eye and complete darkness conditions, postural sway was significantly higher than in the very low illumination condition regardless of the age of the participants.
The silica particle interactions in the presence of spermidine were systematically investigated both from experimental and theoretical points of view. The hydrodynamic radii and the corresponding polydispersity indices of the colloidal silica particles were determined by dynamic light scattering as a function of spermidine concentration. Experimental results were compared with Monte Carlo simulations and theoretical studies.
Many clinical trials in which individuals received one or more dietary antioxidants failed to demonstrate conclusive effects of antioxidant supplementation. Antioxidant supplements do not seem to protect sufficiently against oxidative stress, oxidative damage or to increase lifespan. Some recent studies implied that antioxidant therapy can even increase mortality. In this paper, the idea is presented that antioxidants in their oxidative forms may have more health-beneficial effects than their reduced forms. It seems that it is not the anti-oxidative potential of the antioxidants that has the major role in health-improvement, but rather their involvement in cell signaling processes, regulation of transcription factor activities and other determinants of gene expression. Although oxidized forms of dietary antioxidants may be toxic, their low concentrations might trigger an adaptive stress response (hormesis) and provoke an increased endogenous antioxidant protection and an activation of damage repair processes. Thus, if proved beneficial, the food supplements should contain also low to moderate concentration of specific antioxidants in their oxidized forms.
Titanium and titanium alloys are considered to be one of the most applicable materials in medical devices because of their suitable properties, most importantly high corrosion resistance and the specific combination of strength with biocompatibility. Titanium dioxide nanotubes were created by electrochemical anodization. We investigated binding of various plasma proteins with different sizes and charges on nanotubes. Results showed effective and comparatively higher protein binding to nanotubes with 100 nm diameters (compared to 50 or 15nm).