The role of metallic nano- and microparticles in the development of inflammation has not yet been investigated. Soft tissue biopsy specimens of the bone bed taken during surgical revisions, as well ...as supernatants obtained from the surface of the orthopedic structures and dental implants (control), were examined. Investigations were performed using X-ray microtomography, X-ray fluorescence analysis, and scanning electron microscopy. Histological studies of the bone bed tissues were performed. Nanoscale and microscale metallic particles were identified as participants in the inflammatory process in tissues. Supernatants containing nanoscale particles were obtained from the surfaces of 20 units of new dental implants. Early and late apoptosis and necrosis of immunocompetent cells after co-culture and induction by lipopolysaccharide and human venous blood serum were studied in an experiment with staging on the THP-1 (human monocytic) cell line using visualizing cytometry. As a result, it was found that nano- and microparticles emitted from the surface of the oxide layer of medical devices impregnated soft tissue biopsy specimens. By using different methods to analyze the cell-molecule interactions of nano- and microparticles both from a clinical perspective and an experimental research perspective, the possibility of forming a chronic immunopathological endogenous inflammatory process with an autoimmune component in the tissues was revealed.
Multiple studies have demonstrated that various nanoparticles (NPs) stimulate osteogenic differentiation of mesenchymal stem cells (MSCs) and inhibit adipogenic ones. The mechanisms of these effects ...are not determined. The aim of this paper was to estimate Wharton's Jelly MSCs phenotype and humoral factor production during tri-lineage differentiation per se and in the presence of silicon-gold NPs. Silicon (SiNPs), gold (AuNPs), and 10% Au-doped Si nanoparticles (SiAuNPs) were synthesized by laser ablation, characterized, and studied in MSC cultures before and during differentiation. Humoral factor production (
= 41) was analyzed by Luminex technology. NPs were nontoxic, did not induce ROS production, and stimulated G-CSF, GM-CSF, VEGF, CXCL1 (GRO) production in four day MSC cultures. During MSC differentiation, all NPs stimulated CD13 and CD90 expression in osteogenic cultures. MSC differentiation resulted in a decrease in multiple humoral factor production to day 14 of incubation. NPs did not significantly affect the production in chondrogenic cultures and stimulated it in both osteogenic and adipogenic ones. The major difference in the protein production between osteogenic and adipogenic MSC cultures in the presence of NPs was VEGF level, which was unaffected in osteogenic cells and 4-9 times increased in adipogenic ones. The effects of NPs decreased in a row AuNPs > SiAuNPs > SiNPs. Taken collectively, high expression of CD13 and CD90 by MSCs and critical level of VEGF production can, at least, partially explain the stimulatory effect of NPs on MSC osteogenic differentiation.
The purpose of this study was to provide an immuno-mediated substantiation of the etiopathogenesis of mucositis and peri-implantitis based on the results of experimental, laboratory and clinical ...studies. The biopsy material was studied to identify impregnated nanoscale and microscale particles in the structure of pathological tissues by using X-ray microtomography and X-ray fluorescence analyses. Electron microscopy with energy-dispersive analysis identified the composition of supernatants containing nanoscale metal particles obtained from the surfaces of dental implants. The parameters of the nanoscale particles were determined by dynamic light scattering. Flow cytometry was used to study the effect of nanoscale particles on the ability to induce the activation and apoptosis of immunocompetent cells depending on the particles' concentrations during cultivation with the monocytic cell line THP-1 with the addition of inductors. An analysis of the laboratory results suggested the presence of dose-dependent activation, as well as early and late apoptosis of the immunocompetent cells. Activation and early and late apoptosis of a monocytic cell line when THP-1 was co-cultured with nanoscale metal particles in supernatants were shown for the first time. When human venous blood plasma was added, both activation and early and late apoptosis had a dose-dependent effect and differed from those of the control groups.
To the present, different efficient but expensive, multistage, and time-consuming technologies have been developed to deliver ribonucleic acids (RNA) into eukaryotic cells. Here, we report a simple ...and feasible solution to design RNA nanocarriers based on nucleic acid condensation by bi- and trivalent metal ions during thermal cycling. Efficient RNA conversion to nanoparticles with small size (10-50 nm) suitable for transfection was achieved using cations Ni
2+
, Co
2+
or Cu
2+
alone or in combination with Ca
2+
at the specially selected concentrations (2.0 mM-3.5 mM), low ionic strength, and narrow pH range (8.0-8.5). Other ions - Mn
2+
, Zn
2+
, Tb
3+
, or Gd
3+
- caused RNA-cleaving effect that was abolished in the presence of Ni
2+
, Co
2+
, Zn
2+
, or Cu
2+
. Naked RNA-metal ion nanoparticles were extremely unstable in phosphate buffer and sensitive to serum ribonucleases (RNases), and this problem was solved by treatment with polyarginines-16 and 8. Polyarginine-stabilized nanoparticles, containing malachite green (MG) aptamer RNA and metal cations, crossed the cell membrane, dissociated in the cytoplasm, and preserved the functionality of transported RNA, as judged from efficient transfection of human embryonic kidney 293 cells. The technology, involving RNA condensation by metal cations, can be used as a cheap alternative to produce nanoscale carriers to deliver various RNAs into cells in vitro and in vivo.
Communicated by Ramaswamy H. Sarma
Here, we propose and study several types of quartz surface coatings designed for the high-performance sorption of biomolecules and their subsequent detection by a photonic crystal surface mode (PC ...SM) biosensor. The deposition and sorption of biomolecules are revealed by analyzing changes in the propagation parameters of optical modes on the surface of a photonic crystal (PC). The method makes it possible to measure molecular and cellular affinity interactions in real time by independently recording the values of the angle of total internal reflection and the angle of excitation of the surface wave on the surface of the PC. A series of dextrans with various anchor groups (aldehyde, carboxy, epoxy) suitable for binding with bioligands have been studied. We have carried out comparative experiments with dextrans with other molecular weights. The results confirmed that dextran with a Mw of 500 kDa and anchor epoxy groups have a promising potential as a matrix for the detection of proteins in optical biosensors. The proposed approach would make it possible to enhance the sensitivity of the PC SM biosensor and also permit studying the binding process of low molecular weight molecules in real time.
The emission of nanoscale particles from the surfaces of dental implants leads to the cumulative effect of particle complexes in the bone bed and surrounding soft tissues. Aspects of particle ...migration with the possibility of their involvement in the development of pathological processes of systemic nature remain unexplored. The aim of this work was to study protein production during the interaction of immunocompetent cells with nanoscale metal particles obtained from the surfaces of dental implants in the supernatants. The ability to migrate nanoscale metal particles with possible involvement in the formation of pathological structures, in particular in the formation of gallstones, was also investigated. The following methods were used: microbiological studies, X-ray microtomography, X-ray fluorescence analysis, flow cytometry, electron microscopy, dynamic light scattering, and multiplex immunofluorescence analysis. For the first time, titanium nanoparticles in gallstones were identified by X-ray fluorescence analysis and electron microscopy with elemental mapping. The multiplex analysis method revealed that the physiological response of the immune system cells, in particular neutrophils, to nanosized metal particles significantly reduced TNF-a production both through direct interaction and through double lipopolysaccharide-induced signaling. For the first time, a significant decrease in TNF-a production was demonstrated when supernatants containing nanoscale metal particles were co-cultured with proinflammatory peritoneal exudate obtained from the peritoneum of the C57Bl/6J inbred mice line for one day.
The transparent titanium-zirconium-containing gel was obtained using heteroligand coordination compounds (namely, alkoxoacetylacetonates) as the precursors. The high-dispersive system “ZrTiO4 – ...carbon”, formed after drying of such gel and carbonization of the obtained xerogel, was used to study the evolution of microstructure for the product (ZrTiO4) during thermal treatment in air for 1 h in the temperature range from 500 °C to 1000°С. It was stated that the formation of crystalline phase occurred in the narrow range 690-730°С. The thermal treatment at 500 °C and 600°С allowed obtaining micro- and mesoporous X-ray amorphous products of the composition ZrTiO4, with the specific surface area falling in the range 82–150 m2/g. At the higher temperatures the single-phase nanocrystalline powder was prepared (the specific surface area amounted to 2.5–15 m2/g). Particle coarsening took place more extensively at temperatures ≥700°С was shown. For the ZrTiO4 nanopowder crystallized under the mildest conditions at the temperature of 700 °C, chemoresistive gas-sensitive properties were studied for the first time. The material showed a high reproducible response at 1–20% O2 and 200–10,000 ppm H2 at a relatively low detection operating temperature of 450 °C.
Display omitted
•Method for the preparation of transparent Ti–Zr -containing gel was developed.•The production of high-porous ZrTiO4 on the basis of such gel was studied.•The evolution of its structure in various synthetic conditions was investigated.•The possibility of ZrTiO4 high resistive response to O2 and H2 at 450 °C was shown for the first time.
Interaction between porphyrins and quantum dots (QD) via energy and/or charge transfer is usually accompanied by reduction of the QD luminescence intensity and lifetime. However, for CdSe/ZnS-Cys QD ...water solutions, kept at 276 K during 3 months (aged QD), the significant increase in the luminescence intensity at the addition of
meso
-tetrakis (p-sulfonato-phenyl) porphyrin (TPPS
4
) has been observed in this study. Aggregation of QD during the storage provokes reduction in the quantum yield and lifetime of their luminescence. Using steady-state and time-resolved fluorescence techniques, we demonstrated that TPPS
4
stimulated disaggregation of aged CdSe/ZnS-Cys QD in aqueous solutions, increasing the quantum yield of their luminescence, which finally reached that of the fresh-prepared QD. Disaggregation takes place due to increase in electrostatic repulsion between QD at their binding with negatively charged porphyrin molecules. Binding of just four porphyrin molecules per single QD was sufficient for total QD disaggregation. The analysis of QD luminescence decay curves demonstrated that disaggregation stronger affected the luminescence related with the electron-hole annihilation in the QD shell. The obtained results demonstrate the way to repair aged QD by adding of some molecules or ions to the solutions, stimulating QD disaggregation and restoring their luminescence characteristics, which could be important for QD biomedical applications, such as bioimaging and fluorescence diagnostics. On the other hand, the disaggregation is important for QD applications in biology and medicine since it reduces the size of the particles facilitating their internalization into living cells across the cell membrane.
We propose and demonstrate dendrimer-based coatings for a sensitive biochip surface that enhance the high-performance sorption of small molecules (i.e., biomolecules with low molecular weights) and ...the sensitivity of a label-free, real-time photonic crystal surface mode (PC SM) biosensor. Biomolecule sorption is detected by measuring changes in the parameters of optical modes on the surface of a photonic crystal (PC). We describe the step-by-step biochip fabrication process. Using oligonucleotides as small molecules and PC SM visualization in a microfluidic mode, we show that the PAMAM (poly-amidoamine)-modified chip's sorption efficiency is almost 14 times higher than that of the planar aminosilane layer and 5 times higher than the 3D epoxy-dextran matrix. The results obtained demonstrate a promising direction for further development of the dendrimer-based PC SM sensor method as an advanced label-free microfluidic tool for detecting biomolecule interactions. Current label-free methods for small biomolecule detection, such as surface plasmon resonance (SPR), have a detection limit down to pM. In this work, we achieved for a PC SM biosensor a Limit of Quantitation of up to 70 fM, which is comparable with the best label-using methods without their inherent disadvantages, such as changes in molecular activity caused by labeling.
The detection of double bonds in polymers exploited as scaffold materials, e.g. hyaluronic acid (HA) derivatives, is crucial for their further applications. The quantity variations of unsaturated ...units significantly affect the photoinduced crosslinking degree responsible for the mechanical properties of scaffolds. We demonstrate a simple, selective and rapid quantitative method that enables the detection of double bond moieties in polymers. The approach is based on a reaction with potassium permanganate which is spectrophotometrically confirmed. The effect of glycidyl methacrylate concentration and various reaction catalysts introduced at the stage of HA modification, as well as the change of double bond concentration over time, has been investigated using the proposed method. In addition, the developed quantitative method can be utilized for rapid and efficient detection of unreacted double bonds after photopolymerization as a tool for monitoring conversion over time.
PDF
