Search

The process of stone formation in the human body remains incompletely understood, which requires clinical and laboratory studies and the formulation of a new endogenous, nanotechnological concept of the mechanism of origin and formation of crystallization centers. Previously, the mechanism of sialolithiasis was considered a congenital disease associated with the pathology of the ducts in the structure of the glands themselves. To date, such morphological changes of congenital nature can be considered from the position of the intrauterine formation of endogenous bacterial infections complicated by the migration of antigenic structures initiating the formation of crystallization centers. The present work is devoted to the study of the morphology and composition of stones obtained as a result of surgical interventions for sialolithiasis. Presumably, nanoparticles of metals and other chemical compounds can be structural components of crystallization centers or incorporated into the conditions of chronic endogenous inflammation and the composition of antigenic structures, in complexes with protein and bacterial components. X-ray microtomography, X-ray fluorescence analysis, scanning transmission electron microscopy and microanalysis, mass spectrometry, and Raman spectroscopy were used to study the pathogenesis of stone formation. Immunoglobulins (Igs) of classes A and G, as well as nanoparticles of metals Pb, Fe, Cr, and Mo, were found in the internal structure of the stones. The complex of antigenic structures was an ovoid calcified layered matrix of polyvid microbial biofilms, with the inclusion of metal nanoparticles and chemical elements, as well as immunoglobulins. The obtained results of clinical and laboratory studies allow us to broaden the view on the pathogenesis of stone formation and suggest that the occurrence of the calcification of antigenic structures may be associated with the formation of IgG4-associated disease. [ABSTRACT FROM AUTHOR]

We studied the toxic effects of cerium and fluoride species on human dental pulp stem cells and epithelial cells of Cercopithecus aethiops as a surrogate for the human oral mucosa. The sequential use of CeCl3 and NH4F solutions in equimolar sub-toxic concentrations enabled the possible toxic effects of individual components to be avoided, ensuring the preservation of the metabolic activity of the cells due to the formation of CeF3 nanoparticles. Cerium fluoride nanoparticles and terbium-doped cerium fluoride nanoparticles exhibited neither cytotoxicity nor genotoxicity to dental pulp stem cells, even at high concentrations (10−4 M). In millimolar concentrations (from 10−5–10−6 M), these nanoparticles significantly increased the expression of genes responsible for the cell cycle, differentiation and proliferation. The formation of cerium fluoride on the surface of the mucous membrane and teeth provided protection against the development of carious lesions, periodontitis, ROS attacks and other inflammatory diseases of the oral cavity. Luminescent CeF3: Tb nanoparticles enabled the visualization of tooth enamel microcracks.

Аim — to compare the constancy of maintaining the size of the air gap in standard surgical incisions of the oral mucosa using a diode laser performed by a manipulation robot and by the hand of a surgeon. Material and Methods — A manipulative robotic mechanism coupled with a medical instrument – a semiconductor laser with a nanosecond pulsed pumping driver with a wavelength of λ = 1260 μm was used for the study. A comparative tool for simulating manual movement was a working organ with a nozzle for holding in surgeon’s hand. The study was conducted on three typical trajectories: linear, semilunar and scalloped. The point coordinates were obtained by scanning the position of the reflector of the coordinate measuring machine in 100 passes with the calculation of the value of the standard deviation of the various measured quantities. Results — it was estimated that the magnitude of the spread of the air gap on typical trajectories between the laser tip and the treated biological tissue perfofmed by the robot is on the average 7 times less (p

Previously, we have suggested a hypothesis that the metabolic net water efflux from the cells is a key mechanism for metabolic controlling semipermeable properties of the cell membrane, dysfunction of which is a common consequence of cell pathology. The existence of the electrogenic Na/K-pump in the cell membrane, beating high ATP utilizing the machine in cell, which by activation of mitochondrial function stimulate endogen water formation making it as a key mechanism for the generation of metabolic water efflux from the cells and its dysfunction as a primary step of cell pathology. It is known that the intracellular concentration Ca2+([Ca]i) which is a strong inhibitor for Na/K-pump, controlling by intracellular cyclic nucleotides dependent systems that are extra sensitive to weak chemical and physical signals, unable to activate ionic channels in the membrane. In our earlier studies, we have shown that the activation of both cGMP-activated Ca-pump in the cell membrane and Na/Ca exchange in forwarding (F) mode and cAMP-activated Na/Ca exchange in reverse (R) mode by generating water efflux from the cells, having key roles in controlling low permeability membrane for inward Na+ current (INa) controlling semipermeable properties of membrane and gradient these ions on the membrane, i.e they have a protective function of cell preceding to inward water-induced decrease Na gradient on the cell membrane. It was shown that the soluble guanylate cyclase (sGC) which is sensitive even to water structure changes of cell bathing medium, serves as a sensor for activation cGMP-dependent FNa/Ca exchange while G proteins in the membrane are sensors for activation cAMP-dependent RNa/Ca exchange. The cGMP induced activation of Ca-pump and FNa/Ca exchange by the decrease of [Ca]i–induced activation of Na/K pump activate water efflux from the cell and controlling the Na gradient on the membrane. While the same function doing the cAMP-dependent RNa/Ca exchange because of its electrogenicity and [Ca]i–induced activation of mitochondrial formation water molecules. By our previous study have shown that the activation of cGMP-dependent FNa/Ca exchange has pain relief while the activation of cAMP-dependent RNa/Ca exchange pain generation effects. It was also shown also that 4Hz pulsing magnetic fields, which activation of cGMP- dependent FNa/Ca exchange have relaxation effects on heart muscles and depressed acetylcholine (Ach) sensitivity cell membrane sensitivity, pain relief and antitumor effects. The accumulation of our and literature data on pain and stress relief, antitumor and antivirus effects of 4Hz PMF allow us to hypothesizes that 4Hz–induced activation of cGMP-dependent F Na/Ca exchange can serve as a universal therapeutic tool to increase the resistance of the cells to pathological factors directed to reverse water efflux into water influx in the cells and increases inward Na current which is the primary step of cell pathology. To check this hypothesis, in this present work the 4Hz effect on voluntary patients who have been subjected by different stress on biochemical characteristics of blood we have studied which serve as a marker for pain–the stress of organism.

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

We studied the toxic effects of cerium and fluoride species on human dental pulp stem cells and epithelial cells of Cercopithecus aethiops as a surrogate for the human oral mucosa. The sequential use of CeCl3 and NH4F solutions in equimolar sub-toxic concentrations enabled the possible toxic effects of individual components to be avoided, ensuring the preservation of the metabolic activity of the cells due to the formation of CeF3 nanoparticles. Cerium fluoride nanoparticles and terbium-doped cerium fluoride nanoparticles exhibited neither cytotoxicity nor genotoxicity to dental pulp stem cells, even at high concentrations (10−4 M). In millimolar concentrations (from 10−5–10−6 M), these nanoparticles significantly increased the expression of genes responsible for the cell cycle, differentiation and proliferation. The formation of cerium fluoride on the surface of the mucous membrane and teeth provided protection against the development of carious lesions, periodontitis, ROS attacks and other inflammatory diseases of the oral cavity. Luminescent CeF3: Tb nanoparticles enabled the visualization of tooth enamel microcracks. [ABSTRACT FROM AUTHOR]

Copyright of Ajastan Kensabanakan Handes is the property of National Academy of Sciences of the Republic of Armenia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

FlhDC is a heterohexameric complex that acts as a master regulator of flagellar biosynthesis genes in numerous bacteria. Previous studies have identified a single flhDC operon encoding this complex. However, we found that two flhDC loci are present throughout Paraburkholderia , and two additional flhC copies are also present in Paraburkholderia unamae. Systematic deletion analysis in P. unamae of the different flhDC copies showed that one of the operons, flhDC1 , plays the predominant role, with deletion of its genes resulting in a severe inhibition of motility and biofilm formation. Expression analysis using promoter- lacZ fusions and real-time quantitative PCR support the primary role of flhDC1 in flagellar gene regulation, with flhDC2 a secondary contributor. Phylogenetic analysis shows the presence of the flhDC1 and flhDC2 operons throughout Paraburkholderia . In contrast, Burkholderia and other bacteria only carry the copy syntenous with flhDC2 . The variations in impact each copy of flhDC has on downstream processes indicate that regulation of FlhDC in P. unamae , and likely other Paraburkholderia species, is regulated at least in part by the presence of multiple copies of these genes. IMPORTANCE Motility is important in the colonization of plant roots by beneficial and pathogenic bacteria, with flagella playing essential roles in host cell adhesion, entrance, and biofilm formation. Flagellar biosynthesis is energetically expensive. Its complex regulation by the FlhDC master regulator is well studied in peritrichous flagella expressing enterics. We report the unique presence throughout Paraburkholderia of multiple copies of flhDC . In P. unamae , the flhDC1 copy showed higher expression and a greater effect on swim motility, flagellar development, and regulation of downstream genes, than the flhDC2 copy that is syntenous to flhDC in Escherichia coli and pathogenic Burkholderia spp. The flhDC genes have evolved differently in these plant-growth-promoting bacteria, giving an additional layer of complexity in gene regulation by FlhDC.