Publications by authors named "Alexandru Radu Biris"

Craniofacial bone structures are frequently and extensively affected by trauma, tumors, bone infections and diseases, age-related degeneration and atrophy, as well as congenital malformations and developmental anomalies. Consequently, severe encumbrances are imposed on both patients and healthcare systems due to the complex and lengthy treatment duration. The search for alternative methods to bone transplantation, grafting and the use of homologous or heterologous bone thus responds to one of the most significant problems in human medicine.

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Graphene-oxide (GO) and its most encountered derivatives, thermally reduced graphene oxide (TRGO) and nitrogen-doped graphene (N-Gr), were synthesized and structurally characterized by spectroscopic techniques, like Raman and (13)C MAS solid state NMR. Several biological effects (cytotoxicity, oxidative stress induction, and cellular and mithocondrial membrane alterations) induced by such graphene-based materials on human dental follicle stem cells were investigated. Graphene oxide shows the lowest cytotoxic effect, followed by the nitrogen-doped graphene, while thermally reduced graphene oxide exhibits high cytotoxic effects.

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Four stochastic microsensors based on nanostructured materials (graphene, maltodextrin (MD), and diamond) integrated in miniaturized platforms were proposed. Monocyte chemoattractant protein-1 (MCP-1) is a pro-inflammatory cytokine whose main function is to regulate cell trafficking. It is correlated with the incidence of cardiovascular diseases and obesity, and was used as the model analyte in this study.

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The purpose of this study was to evaluate the biocompatibility of some composites consisting of different proportions of graphene in combination with gold nanoparticles (AuNPs) and nanostructured hydroxyapatite (HA) on osteoblast viability, proliferation and differentiation. Au/HA@graphene composites synthesized by the catalytic chemical vapor deposition induction heating method with acetylene as the carbon source and over an Au/HA catalyst, were characterized by transmission electron microscopy, thermogravimetric analysis and Raman spectroscopy and showed that the few-layer graphene was grown over the Au/HA catalyst. The cytocompatibility study was performed using the fluorescein diacetate assay for assessment of the viability and proliferation of osteoblasts cultivated in the presence of HA, Au/HA and Au/HA@graphene composites as colloidal suspensions or as substrates.

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The oxidative damage of deoxyribonucleic acid (DNA) has been intensively studied due to its role in the occurrence of some diseases. The hydrogen peroxide (H2O2) is one of the reactive oxygen species (ROS). It can induce oxidation of DNA bases, sugar lesions or DNA strand breaks.

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In recent years, a great deal of studies have focused on the possible toxicity of carbon nanotubes (CNT), as a result of their potential applications in the field of nanotechnologies. The investigation of spleen toxicity is part of the carbon nanotubes-induced toxicity assessment. In this study, we investigated the possible toxic effects of CNT on the rat spleen, after intraperitoneally (i.

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Multi-walled carbon nanotubes (MWCNTs) are widely used for nanotechnology. Their impact on living organisms is, however, not entirely clarified. Oxidative stress and inflammation seem to be the key mechanisms involved in MWCNTs' cytotoxicity.

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