Browsing by Author "Rakocevic, Zlatko (7003621821)"

There is an increasing interest in bone nano-structure, the ultimate goal being to reveal the basis of age-related bone fragility. In this study, power spectral density (PSD) data and fractal dimensions of the mineralized bone matrix were extracted from atomic force microscope topography images of the femoral neck trabeculae. The aim was to evaluate age-dependent differences in the mineralized matrix of human bone and to consider whether these advanced nano-descriptors might be linked to decreased bone remodeling observed by some authors and age-related decline in bone mechanical competence. The investigated bone specimens belonged to a group of young adult women (n = 5, age: 20-40 years) and a group of elderly women (n = 5, age: 70-95 years) without bone diseases. PSD graphs showed the roughness density distribution in relation to spatial frequency. In all cases, there was a fairly linear decrease in magnitude of the power spectra with increasing spatial frequencies. The PSD slope was steeper in elderly individuals (-2.374 vs. -2.066), suggesting the dominance of larger surface morphological features. Fractal dimension of the mineralized bone matrix showed a significant negative trend with advanced age, declining from 2.467 in young individuals to 2.313 in the elderly (r = 0.65, P = 0.04). Higher fractal dimension in young women reflects domination of smaller mineral grains, which is compatible with the more freshly remodeled structure. In contrast, the surface patterns in elderly individuals were indicative of older tissue age. Lower roughness and reduced structural complexity (decreased fractal dimension) of the interfibrillar bone matrix in the elderly suggest a decline in bone toughness, which explains why aged bone is more brittle and prone to fractures. © 2012 The Authors Journal of Anatomy © 2012 Anatomical Society.

There is an increasing interest in bone nano-structure, the ultimate goal being to reveal the basis of age-related bone fragility. In this study, power spectral density (PSD) data and fractal dimensions of the mineralized bone matrix were extracted from atomic force microscope topography images of the femoral neck trabeculae. The aim was to evaluate age-dependent differences in the mineralized matrix of human bone and to consider whether these advanced nano-descriptors might be linked to decreased bone remodeling observed by some authors and age-related decline in bone mechanical competence. The investigated bone specimens belonged to a group of young adult women (n = 5, age: 20-40 years) and a group of elderly women (n = 5, age: 70-95 years) without bone diseases. PSD graphs showed the roughness density distribution in relation to spatial frequency. In all cases, there was a fairly linear decrease in magnitude of the power spectra with increasing spatial frequencies. The PSD slope was steeper in elderly individuals (-2.374 vs. -2.066), suggesting the dominance of larger surface morphological features. Fractal dimension of the mineralized bone matrix showed a significant negative trend with advanced age, declining from 2.467 in young individuals to 2.313 in the elderly (r = 0.65, P = 0.04). Higher fractal dimension in young women reflects domination of smaller mineral grains, which is compatible with the more freshly remodeled structure. In contrast, the surface patterns in elderly individuals were indicative of older tissue age. Lower roughness and reduced structural complexity (decreased fractal dimension) of the interfibrillar bone matrix in the elderly suggest a decline in bone toughness, which explains why aged bone is more brittle and prone to fractures. © 2012 The Authors Journal of Anatomy © 2012 Anatomical Society.

In our recent studies we have designed fullerenol/doxorubicin nanocomposite (FNP/DOX) as the new drug nanocarrier. This research has demonstrated that this novel nanocomposite has had better implications on the liver tissue in vivo (Wistar rats treated intraperitoneally), than treatment based only on DOX. FNP/DOX has been characterised by DLS, TEM and AFM measurements which have shown that DOX loaded onto FNP did not influence fullerenol nanoparticle's size. FNP/DOX affected oxidative status in blood causing a significant decrease of catalase and SOD activity in comparison to DOX, implicating the reduction in oxidative stress. qRT-PCR results on the mRNA level of antioxidative enzymes (catalase and MnSOD) revealed that the effect of oxidative stress is significantly reduced by the treatment with FNP/DOX (p <.05). The ultrastructural analysis of the liver tissue has revealed that FNP/DOX nanocomposite generated considerably less damage in the liver tissue, than DOX applied at the same dose. Hence, our results have indicated that FNP, within FNP/DOX nanocomposite, exhibits protective effects to the liver tissue of the healthy rats. © 2018

In our recent studies we have designed fullerenol/doxorubicin nanocomposite (FNP/DOX) as the new drug nanocarrier. This research has demonstrated that this novel nanocomposite has had better implications on the liver tissue in vivo (Wistar rats treated intraperitoneally), than treatment based only on DOX. FNP/DOX has been characterised by DLS, TEM and AFM measurements which have shown that DOX loaded onto FNP did not influence fullerenol nanoparticle's size. FNP/DOX affected oxidative status in blood causing a significant decrease of catalase and SOD activity in comparison to DOX, implicating the reduction in oxidative stress. qRT-PCR results on the mRNA level of antioxidative enzymes (catalase and MnSOD) revealed that the effect of oxidative stress is significantly reduced by the treatment with FNP/DOX (p <.05). The ultrastructural analysis of the liver tissue has revealed that FNP/DOX nanocomposite generated considerably less damage in the liver tissue, than DOX applied at the same dose. Hence, our results have indicated that FNP, within FNP/DOX nanocomposite, exhibits protective effects to the liver tissue of the healthy rats. © 2018