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OBJECTIVE: Although pure titanium (PT) and its alloys exhibit excellent mechanical properties, they lack biological activity as implants. The purpose of this study was to improve the biological activity of titanium implants through surface modification. MATERIALS AND METHODS: Titanium was processed into titanium discs, where the titanium discs served as anodes and stainless steel served as cathodes, and a copper- and cobalt-doped porous coating [pure titanium model (PTM)] was prepared on the surface of titanium via plasma electrolytic oxidation. The surface characteristics of the coating were evaluated using field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and profilometry. The corrosion resistance of PTM was evaluated with an electrochemical workstation. The biocompatibility and bioactivity of coated bone marrow mesenchymal stem cells (BMSCs) were evaluated through in vitro cell experiments. RESULTS: A copper- and cobalt-doped porous coating was successfully prepared on the surface of titanium, and the doping of copper and cobalt did not change the surface topography of the coating. The porous coating increased the surface roughness of titanium and improved its resistance to corrosion. In addition, the porous coating doped with copper and cobalt promoted the adhesion and spreading of BMSCs. CONCLUSIONS: A porous coating doped with copper and cobalt was prepared on the surface of titanium through plasma electrolytic oxidation. The coating not only improved the roughness and corrosion resistance of titanium but also exhibited good biological activity. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The aim of this study was to investigate the protective effect of recombinant erythropoietin at different doses on brain injury in premature infants and the related effects on blood routine, liver function, intellectual development, mental development index (MDI), psychomotor development index (PDI), etc. PATIENTS AND METHODS: A total of 120 premature infants were divided into four groups, including experimental group A (n=30), experimental group B (n=30), experimental group C (n=30) and control group (n=30). The experimental group was treated with different doses of recombinant erythropoietin for brain injury protection of premature infants, while the control group with conventional methods. RESULTS: There was no statistical significance in all test indicators of the four groups of patients before the intervention. After the intervention experiment, the S-100B index was p<0.05, and the erythropoietin (EPO) index was p<0.05. In the comparison of IL-6 indicators, the indicators of the experimental group were reduced after the comparison experiment, and there were significant differences, p<0.05. In neonatal behavior evaluation, there was a statistical difference between groups A and B and the control group (p<0.05), and no statistical significance was shown between group C and the control group (p>0.05). In the intelligence test comparison, the F value of the experimental group was 3.113 three months after treatment. After six months, the F value was 3.654. After nine months, the F value was 3.392 with p<0.05. In the comparison of blood routine indicators, the p-values of four indicators between groups were more than 0.05. In the comparison of liver function indexes, the indexes of groups A, B, and C were significantly changed before and after treatment, and the data after treatment were significantly different from those before treatment, p<0.05. In the comparison of development, there were no significant differences observed in the p-values of the two indicators of vigorous exercise and language in the experimental group. CONCLUSIONS: Recombinant erythropoietin has a protective effect on infants with brain injury and can improve the intellectual development of premature infants, but has no significant effect on blood routine indicators. It can effectively improve the MDI, PDI, and related cytokines of premature infants, and has certain significance for the treatment of brain injury. [ABSTRACT FROM AUTHOR]

The mesoporous graphene oxide-supported ferroferric oxide (Fe3O4/GO) nanocomposites (the average size of 30.08 nm) were controllably synthesized in the present study. The successful in situ growth of Fe3O4 nanoparticles on GO surface was ascribed to the oxygen-containing groups on GO. The magnetic separation was employed for Sb(III) removal from aqueous solutions and artificial intelligence techniques were adopted to reduce the number and cost of experiments, in order to render these nanocomposites of a practical value. The three methods, including response surface methodology (RSM), artificial neural network-genetic algorithm (ANN-GA) and artificial neural network-particle swarm optimization (ANN-PSO), were used to model and optimize the removal of Sb(III) from aqueous solutions. These three models were evaluated based on correlation coefficient (R2) and mean squared error (MSE). The higher R2 value and lower MSE of ANN-GA demonstrated the superiority of ANN-GA model over ANN-PSO and RSM models. Analysis of variance, gradient boosted regression trees (GBRT) and Garson method exhibited that contact time was the most influential variable for the Sb(III) removal. Fitting of isotherm data showed that the removal process was controlled by the monolayer adsorption on a homogeneous surface based on the values of R2, x2, sum of absolute errors (SAE) and average percentage errors (APE). The adsorption process followed the pseudo-second-order model, which was spontaneous and entropy-driven. It was observed that the adsorption process was accompanied with the redox reaction based on the XPS analysis. The regeneration experiments showed that the mesoporous Fe3O4/GO nanocomposites are an effective and reusable adsorbent within four regeneration cycles. [ABSTRACT FROM AUTHOR]