Correction to: Iron oxides nanoparticles (IOs) exposed to magnetic field promote expression of osteogenic markers in osteoblasts through integrin alpha-3 (INTa-3) activation, inhibits osteoclasts activity and exerts anti-inflammatory action.

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Iron oxides nanoparticles (IOs) exposed to magnetic field promote expression of osteogenic markers in osteoblasts through integrin alpha-3 (INTa-3) activation, inhibits osteoclasts activity and exerts anti-inflammatory action.

BACKGROUND: Prevalence of osteoporosis is rapidly growing and so searching for novel therapeutics. Yet, there is no drug on the market available to modulate osteoclasts and osteoblasts activity simultaneously. Thus in presented research we decided to fabricate nanocomposite able to: (i) enhance osteogenic differentiation of osteoblast, (i) reduce osteoclasts activity and (iii) reduce pro-inflammatory microenvironment. As a consequence we expect that fabricated material will be able to inhibit bone loss during osteoporosis. RESULTS: The α-Fe2O3/γ-Fe2O3 nanocomposite (IOs) was prepared using the modified sol-gel method. The structural properties, size, morphology and Zeta-potential of the particles were studied by means of XRPD (X-ray powder diffraction), SEM (Scanning Electron Microscopy), PALS and DLS techniques. The identification of both phases was checked by the use of Raman spectroscopy and Mössbauer measurement. Moreover, the magnetic properties of the obtained IOs nanoparticles were determined. Then biological properties of material were investigated with osteoblast (MC3T3), osteoclasts (4B12) and macrophages (RAW 264.7) in the presence or absence of magnetic field, using confocal microscope, RT-qPCR, western blot and cell analyser. Here we have found that fabricated IOs: (i) do not elicit immune response; (ii) reduce inflammation; (iii) enhance osteogenic differentiation of osteoblasts; (iv) modulates integrin expression and (v) triggers apoptosis of osteoclasts. CONCLUSION: Fabricated by our group α-Fe2O3/γ-Fe2O3 nanocomposite may become an justified and effective therapeutic intervention during osteoporosis treatment.

A new approach to spectroscopic and structural studies of the nano-sized silicate-substituted hydroxyapatite doped with Eu3+ ions.

Nanocrystalline silicate-substituted hydroxyapatites Ca10-xEux(PO4)4(SiO4)2(OH)2 (where x = 0.5, 1.0, 2.0, 5.0 mol%) doped with Eu3+ ions were synthesized using a microwave assisted hydrothermal method and heat-treated in the temperature range from 700 to 1000 °C. The concentration of optically active Eu3+ ions was established in the range of 0.5-5 mol% to investigate the preference of occupancy sites. The structural and morphological properties of the obtained biomaterials were determined by using XRD (X-Ray Powder Diffraction), TEM (Transmission Electron Microscopy) and SEM (Scanning Electron Microscopy) techniques as well as infrared (IR) spectroscopy. The average particle sizes were calculated to be in the range from 20 nm to 80 nm by the Rietveld method. The charge compensation mechanism in europium(iii)-doped silicate-substituted hydroxyapatite was proposed in the Kröger-Vink-notation. The luminescence properties (the emission, excitation spectra and emission kinetics) of the Eu3+ ion-doped apatite were recorded depending on the dopant concentration. The existence of Eu2+ ions was confirmed by the emission spectra.

Lithium ions (Li+) and nanohydroxyapatite (nHAp) doped with Li+ enhance expression of late osteogenic markers in adipose-derived stem cells. Potential theranostic application of nHAp doped with Li+ and co-doped with europium (III) and samarium (III) ions.

Lithium (Li+) ion due to its excellent bioactivity is one of the most well-studied element in bone-tissue engineering. In this study, we fabricated nanohydroxyapatite (nHAp) doped with Li+ ions (5 mol% Li+:nHAp) and co-doped with lanthanide ions. We investigated the effects of nHAp, 5 mol% Li+:nHAp or Li+ alone, on osteogenic differentiation of human Adipose Tissue-derived Stem Cells (hASCs), their proliferation, mitochondrial dynamics and apoptosis. Moreover, we monitored cell proliferation after treatment with samarium (III) (Sm3+) and europium (III) (Eu3+) ions co-doped 5 mol% Li+:nHAp as well as their luminescent property. The hASCs treated with 5 mol% Li+:nHAp and Li+ ions proliferated more rapidly and differentiated effectively than control cells without undergoing apoptosis. Both, 5 mol% Li+:nHAp and Li+ ions improved osteogenic differentiation of hASCs. Moreover they decreased expression of glycogen synthase kinase 3ß (GSK3ß) while increased ß-catenin mRNA level. In addition, Li+, nHAp and 5 mol% Li+:nHAp improved mitochondrial dynamics and enhanced expression of neural differentiation marker genes. Collectively, the study indicates on pro-osteogenic and anti-apoptotic properties of nHAp doped with Li+ and Li+ alone. Moreover, unique properties of 5 mol% Li+:nHAp and 5 mol% Li+:nHAp co-doped with rare earth ions, such as Sm3+ and Eu3+ have shed a promising light on their potential application in theranostics.

The Effect of Co0.2Mn0.8Fe2O4 Ferrite Nanoparticles on the C2 Canine Mastocytoma Cell Line and Adipose-Derived Mesenchymal Stromal Stem Cells (ASCs) Cultured Under a Static Magnetic Field: Possible Implications in the Treatment of Dog Mastocytoma.

Cobalt manganese ferrite nanoparticles have application potential in the biomedical field, however there is limited information concerning the biological response. The aim of this work was to investigate the cytotoxic potential of cobalt-manganese ferrite nanoparticles in canine mastocytoma tumor cells (C2) and adipose-derived mesenchymal stromal stem cells (ASCs) cultured under a static magnetic field (MF). In this study, we investigated the viability and proliferation rate of ASC and C2 cells cultured with Co0.2Mn0.8Fe2O4 nanoparticles under 0.5T MF. We observed cells morphology and measured intracellular ROS generation. Thermal observations were used to characterize the thermotrophic cell behavior in different condition and RNA level of heat shock proteins and apoptotic genes was measured. Nanoparticles reduced cell viability, caused cell damage, i.e., through the formation of reactive oxygen species (ROS) and increased transcriptional level of apoptotic genes (Bcl-2, Bax, p53, p21). In addition, we have found that C2 mastocytoma cells cultured with metal oxide nanoparticles under MF exhibited unexpected biological responses, including thermotolerance and apoptotic response induced by the expression of heat shock proteins and ROS produced under a MF. Our results suggest that stimulation using MF and Co0.2Mn0.8Fe2O4 nanoparticles is involved in mechanisms associated with controlling cell proliferative potential signaling events. We can state that significant differences between normal and cancer cells in response to nanoparticles and MF are apparent. Our results show that nanoparticles and MF elevate the temperature in vitro in tumor cells, thereby increasing the expression of ROS as well as heat shock proteins.

Multifunctional nanocrystalline calcium phosphates loaded with Tetracycline antibiotic combined with human adipose derived mesenchymal stromal stem cells (hASCs).

Osteoconductive drug delivery system composed of nanocrystalline calcium phosphates (Ca10(PO4)6(OH)2/ß-Ca3(PO4)2) co-doped with Yb(3+)/Er(3+) ions loaded with Tetracycline antibiotic (TC) was developed. Their effect on human adipose derived mesenchymal stromal stem cells (hASCs) as a potential reconstructive biomaterial for bone tissue regeneration was studied. The XRD and TEM measurements were used in order to determine the crystal structure and morphology of the final products. The characteristics of nanocomposites with the TC and hASCs as potential regenerative materials as well as the antimicrobial activity of the nanoparticles against: Staphylococcus aureus ATCC 25923 as a model of the Gram-positive bacteria, Escherichia coli ATCC 8739 of the Gram-negative bacteria, were shown. These combinations can be a promising material for theranostic due to its regenerative, antimicrobial and fluorescent properties.

A new approach in the synthesis of La(1-x)Gd(x)FeO3 perovskite nanoparticles--structural and magnetic characterization.

A series of highly crystalline orthoferrite nanoparticles (type La(1-x)Gd(x)FeO3, where x = 0 to 1) were prepared using the self-combustion method. Extensive studies including X-ray diffraction, Rietveld refinement and Fourier transform infrared spectroscopy as well as Raman spectroscopy confirmed the orthorhombic space group Pnma of the obtained materials. The calculated average grain size for powders is in the range of 30 to 80 nm. Magnetic characterization of the La(1-x)Gd(x)FeO3 series, performed at 1.72 K, indicated an antiferromagnetic state characterized by some canting of iron magnetic moments, in good agreement with the data reported for similar fine-particle systems.

Functional up-converting SrTiO3:Er(3+)/Yb(3+) nanoparticles: structural features, particle size, colour tuning and in vitro RBC cytotoxicity.

SrTiO3 nanoparticles co-doped with a broad concentration range of Er(3+) and Yb(3+) ions were fabricated using the citric route as a function of annealing temperatures of 500-1000 °C. The effect of a broad co-dopant concentration range and sintering temperature on structural and up-conversion properties was investigated in detail by X-ray diffraction techniques and optical spectroscopy. The TEM technique was used to estimate the mean particle size, which was around 30 nm for the inorganic product annealed at 600 °C. Up-conversion emission color tuning was achieved by particle size control. Power dependence of the green and red emissions was found to be a result of temperature determination in the operating range of SrTiO3 nanoparticles and a candidate for the fast and local microscopic heating and heat release induced by IR irradiation. The color changed from white-red-yellow-green upon an increase of sintering temperature, inducing changes in the surface-to-volume ratio and the number of optically active ions in particle surface regions. The cytotoxic activity of nanoparticles on human red blood cells was investigated, showing no harmful effects up to a particle concentration of 0.1 mg ml(-1). The cytotoxic response of a colloidal suspension of nanoparticles to RBC cells was connected with the strong affinity of SrTiO3 particles to the cell membranes, blocking the transport of important biological solutes.

Multifunctional lanthanide and silver ion co-doped nano-chlorapatites with combined spectroscopic and antimicrobial properties.

Nanocrystalline chlorapatites (Ca10(PO4)6Cl2) doped with lanthanide ions (Eu(3+), Er(3+) and Yb(3+)) and co-doped with silver ions (Ag(+)) were synthesized by a hydrothermal synthesis route. XRD, TEM, and SAED measurements indicated that the powders are single phased and crystallize with a hexagonal structure with good dispersion. The results showed well crystallized chlorapatite grains with a diameter of about 45 nm. The antimicrobial activity of the nanoparticles against Escherichia coli ATCC 11229 and ATCC 25922, Klebsiella pneumoniae ATCC 700603, and Pseudomonas aeruginosa PAO1 and ATCC 27853 was studied. The best activity was observed for the Eu(3+),Ag(+):Ca10(PO4)6Cl2 and Eu(3+),Ag(+),Yb(3+):Ca10(PO4)6Cl2 compositions. These multifunctional nanocrystalline powders could be used as a promising antimicrobial agent and material for bio-detection.

Role of the sintering temperature and doping level in the structural and spectral properties of Eu-doped nanocrystalline YVO4.

A sol-gel approach was employed to prepare nanosized YVO(4) nanopowders doped with Eu(3+) ions. Raw nanomaterials were thermally treated at 700-1000 °C for 3 h. X-ray diffraction (XRD) analysis demonstrated that single-phase nanopowders with high crystallite dispersion were obtained. Our studies were focused on relating the luminescence properties of the Eu(3+) dopant to the nanocrystallite (NC) size. Depending on the thermal treatment, the average NC size was calculated to range from 20 nm to 1.1 µm. We have found that the size effect manifests mainly in the expansion of the cell volume and broadening of XRD peaks, as indicated by Rietveld analysis. Moreover, emission and excitation spectra, although typical for the Eu(3+) ions, demonstrated some degree of correlation with the calcination temperature and doping concentration. To explain these differences a detailed analysis of the luminescence spectra by the Judd-Ofelt theory has been performed.

Synthesis, structure, and optical properties of LiEu(PO3)4 nanoparticles.

A wet chemical approach was employed for the preparation of LiEu(PO(3))(4) nanoparticles. XRD, Raman spectroscopy, TEM, SAED, and IR measurements were used in order to determine the crystal structure and morphology of the obtained product. Complete optical studies including absorption, excitation, emission, and kinetic measurements were performed. At least two components of the (5)D(0) → (7)F(0) transition were found, indicating the existence of more than one crystallographic position of the Eu(3+) ions. Asymmetry parameter R as well as the covalence of the Eu-O bond were found to decrease with the grain growth.

Preparation and spectroscopy characterization of Eu:MgAl2O4 nanopowder prepared by modified Pechini method.

In the present work, a modified Pechini method was employed to prepare nanostructured MgAl2O4 spinel powders doped with Eu3+ ions. The XRD analyses demonstrated that the powders were single-phase spinel nanopowders with high crystallite dispersion. The average spinel particle size was determined to be approximately 15 nm for calcination at 700 degrees C, and approximately 20 at 1000 degrees C. The emission and excitation spectra measured for the samples calcinated at 700 and 1000 degrees C demonstrated characteristic spectra of Eu3+ ions as well as were measured the emission spectra of Eu2+ ions for the samples calcinated at 700 degrees C. The effect of MgAl2O4 grain sizes on luminescence properties was noticed. To explain these differences a detailed analysis of luminescence spectra by the Judd-Ofelt theory has been performed.