CLINICOROENTGENOLOGICAL PECULIARITIES OF THE CONGENITAL AND ACQUIRED CRANIOFACIAL ANOMALIES.

The aim of the research was to study the relationship between the X-ray changes in the bones of the skull, the structure of the upper respiratory tract and concomitant general somatic diseases in patients with congenital and acquired craniomaxillofacial anomalies. The study included 52 patients aged 1 to 3 and 3 to 7 years, with congenital and acquired lower micrognathia in 19 (36.53±5.3)% and upper micrognathia in 33 (63.46±5.3)%. There were used clinical methods (questioning, examination, palpation), instrumental methods (multispiral computer tomography, X-ray cephalometric analysis of the bones of the facial skeleton, oropharynx, and bony pharynx). The obtained results of the clinical and radiographic examination made it possible to assert that among the patients with congenital defects of the jaws, not only changes in the facial skeleton dominate, mostly in the form of upper micrognathia and, to a lesser extent, lower micrognathia, but also the presence of somatic developmental defects in the form of disorders of the nervous system, pathologies of ENT-organs and ophthalmic defects. The identified malformations caused the violations of a number of important functions: breathing, swallowing, chewing, and speech formation. This connection was followed in particular in patients with syndromic craniosynostosis, namely, underdevelopment of the skull base combined with upper micrognathia and retroposition of the maxillary complex in the skull. The frequency and spectrum of concomitant somatic pathology depended on the nature of dentofacial anomalies. All patients with upper micrognathia had craniostenosis with the deformations of the brain skull and eye sockets. Among the patients with lower micrognathia, all those examined were found to have disorders of the development of the ENT-organs.

MICROSTRUCTURE OF BIOPOLYMER MICRO-FIBROUS SCAFFOLD AND ITS INFLUENCE ON THE ABILITY TO RETAIN MEDICINES AND TISSUE REGENERATION.

The aim of the research is to study the microstructure, antibiotic-absorbing and framework capacity of the fibrous non-woven PCL matrices designed by us for the regeneration of tissues and capillaries. Samples of microfibrous non-woven matrices made by our technology out of polycaprolactone PCL (invention patent of Ukraine № 119958) were used in the work. Antibiotic retention in samples of matrix materials was evaluated during the 1st, 3rd, 5th, 7th, 14th, 18th and 21st days of the experiment. The experimental part of the research was performed using 30 laboratory animals (rabbits). On the basis of microscopic studies of the biopolymer microfiber matrices obtained by us, the relationship between the increase in polymer concentration in the sucrose melt and the increase in the percentage of thicker microfibers was determined. Microbiological analysis of the antibiotic-absorbing capacity of the obtained microfibrous biopolymer non-woven matrices determined that lincomycin impregnated into polymer matrices is characterized by less stability during storage than cefazolin. Antibiotic concentrations of the impregnated matrix material samples were actively maintained at the level of control values for a period of 5 days. The pathomorphological analysis of soft tissues at all times of subcutaneous implantation in the experiment made it possible to determine the fact of regeneration of tissues and the microcirculatory channel through the entire thickness of the fibrous matrix. This was confirmed by a significant decrease in the area of the connective tissue matrix per vessel from (49345.18+485.63) µm2 to (24797.47+480.28) µm2, an increase in the cross-sectional area of vessels from (697.61+21.79) µm2 to (1321.23+24.82) µm2 and a decrease in the thickness of vascular walls from (3.2+0.05) µm to (2.65+0.07) µm (p<0.01) from the periphery to the center of the frame. These facts, in our opinion, confirm the framework function of the polymer matrix synthesized by us, which is also a means of one-time local delivery of the medicine to the tissues in the damaged area.

EFFECTIVENESS OF THE APPLICATION OF THE DEVELOPED BIOPOLYMER FIBROUS MATRIX WITH CENOBONE® BIOGEL FOR THE RECONSTRUCTION OF BONE TISSUE DEFECTS OF THE JAWS.

The aim of the research was to study the framework ability of the fibrous non-woven PCL matrices we've created during the restoration of bone tissue.There were performed some spectroscopic, histological and immunohistochemical, radiological and clinical analyses of the effectiveness of microfibrous non-woven PCL polycaprolactone matrices developed by us, in the work. The obtained results of morphological studies of bone tissue in the experiment of the implantation of a fibrous matrix indicated an increase in reparative osteogenesis in the form of an increase in osteoid areas up to 34.38% (p<0.05) at an early period. The analysis of clinical data showed the effectiveness of the frame developed by us, which was confirmed by the absence of pronounced compaction of bone tissue in group III, in contrast to group II, where, on the contrary, the use of granulate based on hydroxyapatite and tricalcium phosphate has led to a significant increase in density indices of 974.53+19.74 HU p<0.05, which did not exceed 36.8% of indices of the group III 615.17+24.53 HU p<0.05.The matrix material developed by us is not only a means of delivering some other substances and materials into the damaged area, but also serves as a kind of framework for the restoration of bone tissue.

A Step Toward Making VMAT TBI More Prevalent: Automating the Treatment Planning Process.

PURPOSE: Our purpose was to automate the treatment planning process for total body irradiation (TBI) with volumetric modulated arc therapy (VMAT). METHODS AND MATERIALS: Two scripts were developed to facilitate autoplanning: the binary plug-in script automating the creation of optimization structures, plan generation, beam placement, and setting of the optimization constraints and the stand-alone executable performing successive optimizations. Ten patients previously treated in our clinic with VMAT TBI were used to evaluate the efficacy of the proposed autoplanning process. Paired t tests were used to compare the dosimetric indices of the produced auto plans to the manually generated clinical plans. In addition, 3 physicians were asked to evaluate the manual and autoplans for each patient in a blinded retrospective review. RESULTS: No significant differences were observed between the manual and autoplan global Dmax (P < .893), planning target volume V110% (P < .734), kidneys Dmean (P < .351), and bowel Dmax (P < .473). Significant decreases in the Dmean to the lungs and lungs-1cm (ie, lungs with 1-cm inner margin) volumes of 5.4% ± 6.4% (P < .024) and 6.8% ± 7.4% (P < .017), respectively, were obtained with the autoplans compared with the manual plans. The autoplans were selected 77% of the time by the reviewing physicians as equivalent or superior to the manual plans. The required time for treatment planning was estimated to be 2 to 3 days for the manual plans compared with approximately 3 to 5 hours for the autoplans. CONCLUSIONS: Large reductions in planning time without sacrificing plan quality were obtained using the developed autoplanning process compared with manual planning, thus reducing the required effort of the treatment planning team. Superior lung sparing with the same target coverage and similar global Dmax were observed with the autoplans as compared with the manual treatment plans. The developed scripts have been made open-source to improve access to VMAT TBI at other institutions and clinics.

[Migraine in the real-life clinical practice: results of the observational study of diagnosis and treatment patterns in the urban population of the Russian Federation]. / Migren' v real'noi klinicheskoi praktike: rezul'taty nablyudatel'nogo issledovaniya patternov diagnostiki i lecheniya sredi gorodskogo naseleniya Rossiiskoi Federatsii.

OBJECTIVE: Analysis of real-life clinical practice data regarding the patterns of diagnosis and treatment of migraine in the Russian Federation. MATERIAL AND METHODS: An observational real-world cohort study was conducted from January 2013 to December 2018 (over a 5-year period) to analyze the electronic database of 5 large private clinic chains in Moscow and St. Petersburg. RESULTS: Among 1.15 million people who sought medical care, «G43 Migraine¼ diagnosis was established in 6.650 people, which accounted for 0.6%. A total of 54% of patients were diagnosed by a neurologist, while 35% by a GP. In roughly half the cases, to diagnose migraine, the doctors had to resort to additional methods of examination. While 53% of patients had indications for preventive treatment, it was prescribed only to 12% of those. Of these, the treatment strategy chosen for 29% of patients was changed: either the intragroup/intergroup switching of the medicinal product took place, or the combined treatment was prescribed. CONCLUSION: In the real-life outpatient clinical practice, the level of diagnosis of migraine is extremely low. Additional methods of examination are excessively used for the diagnosis of migraine. The insufficient use of preventive medication and common use of therapies with unsubstantiated efficacy in migraine result in frequent changes in the treatment strategy.

Interactions between nanoparticles in nanosuspension.

Nanoparticles are particles with a characteristic dimension below 100 nm. The properties of nanoparticles differ substantially from those of "big" colloidal particles (size bigger than 1 µm) because radius of surface forces, which is around 100 nm, is greater than or comparable with the nanoparticles size. The latter means that each nanoparticle could be completely covered by the surface forces of the neighbouring particles at small enough separation. It also means that the well-known Derjaguin approximation cannot be applied directly and some modifications are required. Pairwise interaction between nanoparticles can be used only at an extremely low volume fraction of nanoparticles (below some critical volume fraction, which is ~0.02%), and above this concentration a new theory based on many-particle interactions should be applied, which is yet to be developed. Some recent progress in the area of interaction between nanoparticles is reviewed and the properties of nanosuspensions based on interaction between nanoparticles are described. The authors have not attempted to cover all available literature in the area but instead have tried to underline the fundamental problems in the area which need to be addressed.

Spectroscopic features of ultrahigh-pressure impact glasses of the Kara astrobleme.

The state of substances under ultrahigh pressures and temperatures (UHPHT) now raises a special interest as a matter existing under extreme conditions and as potential new material. Under laboratory conditions only small amounts of micrometer-sized matter are produced at a pressure up to 100 GPa and at room temperature. Simultaneous combination of ultrahigh pressures and temperatures in a lab still requires serious technological effort. Here we describe the composition and structure of the UHPHT vein-like impact glass discovered by us in 2015 on the territory of the Kara astrobleme (Russia) and compare its properties with impact glass from the Ries crater (Germany). A complex of structural and spectroscopic methods presents unusual high pressure marks of structural elements in 8-fold co-ordination that had been described earlier neither in synthetic nor natural glasses. The Kara natural UHPHT glasses being about 70 Ma old have well preserved initial structure, presenting some heterogeneity as a result of partial liquation and crystallization differentiation where an amorphous component is proposed to originate from low level polymerization. Homogeneous parts of the UHPHT glasses can be used to deepened fundamental investigation of a substance under extreme PT conditions and to technological studies for novel material creations.

The effect of adsorption kinetics on the rate of surfactant-enhanced spreading.

A comparison of the kinetics of spreading of aqueous solutions of two different surfactants on an identical substrate and their short time adsorption kinetics at the water/air interface has shown that the surfactant which adsorbs slower provides a higher spreading rate. This observation indicates that Marangoni flow should be an important part of the spreading mechanism enabling surfactant solutions to spread much faster than pure liquids with comparable viscosities and surface tensions.

Surfactant-enhanced spreading: Experimental achievements and possible mechanisms.

Surfactants are broadly used to improve wetting properties of aqueous formulations. The improvement is achieved by essential reduction of liquid/air and solid/liquid interfacial tensions resulting in the decrease of contact angle. For moderately hydrophobic substrates, there is a range of surfactants providing complete wetting of substrate. With the decrease of substrate surface energy, this range of surfactants reduces very quickly and only trisiloxane surfactant solutions are capable to wet completely such highly hydrophobic substrates as polypropylene and parafilm. That is why these surfactants are referred to as superspreaders. The most intriguing feature of wetting surfactant solutions is their ability to spread much faster than pure liquids with spread area, S, being proportional to time, t, S~t, as compared to S~t(0.2) for pure liquids, which wet completely the solid substrate. Trisiloxane surfactant solutions spread faster than other aqueous surfactant solutions, which also provide complete wetting, being superspreaders in the sense of spreading rate as well. The mechanism of fast spreading of surfactant solutions on hydrophobic substrates and much higher spreading rates for trisiloxane solutions are to be explained. Below the available experimental data on superspreading and surfactant-enhanced spreading are analysed/summarised, and possible mechanisms governing the fast spreading are discussed.

Wetting films of aqueous solutions of Silwet L-77 on a hydrophobic surface.

The formation of wetting films of aqueous solutions of Silwet L-77 on hydrophobic substrates takes place only at concentrations above the critical aggregation concentration (CAC). At concentrations above the critical wetting concentration (CWC) a new phenomenon was found: the formation of multilayered spots of thicker films in the wetting film of aqueous solutions of Silwet L-77 on hydrophobic surfaces. An expansion of the thicker spots within the film and the formation of "channels" between the spots and the edge of the film led to a continuous shrinkage of the wetting film and its disappearance in the end. We suggested that the multiple thicker films originate from the multilayer structuring of trisiloxane bilayers within the wetting film.

Mixtures of catanionic surfactants can be superspreaders: Comparison with trisiloxane superspreader.

HYPOTHESIS: Mixed solutions of cationic and anionic surfactants show considerable synergism in their wetting behaviour, but their spreading is affected considerably by the phase separation processes. The valuable information about wetting properties of synergetic mixtures can be obtained by using mixtures in which phase separation occurs at concentrations above cmc. EXPERIMENTS: Spreading properties of mixed solutions of cationic and anionic surfactants over highly hydrophobic substrate such as polyethylene are investigated and compared with those for trisiloxane superspreader. Experiments are performed at relative humidity of 40% and 80%. Interfacial tension at water/air and water/alkane interfaces is measured to explain spreading performance. FINDINGS: Catanionic solutions can wet hydrophobic substrates nearly as effective as solutions of trisiloxane superspreader. The spreading factor reaches 70% of that of superspreader for the most effective mixed solution. The spreading slows down earlier at high surfactant concentrations. At room humidity (40%) spread area has a maximum vs concentration. However, the maximum was not observed at higher humidity 80%. Humidity does not affect the short-time spreading rate, but it influences considerably the time when spreading slows down. The spreading rate of mixed solutions is smaller than that of superspreader despite the same spreading exponent α=0.5.

Foam drainage placed on a porous substrate.

A model for drainage/imbibition of a foam placed on the top of a porous substrate is presented. The equation of liquid imbibition into the porous substrate is coupled with a foam drainage equation at the foam/porous substrate interface. The deduced dimensionless equations are solved using a finite element method. It was found that the kinetics of foam drainage/imbibition depends on three dimensionless numbers and the initial liquid volume fraction. The result shows that there are three different regimes of the process. Each regime starts after initial rapid decrease of a liquid volume fraction at the foam/porous substrate interface: (i) rapid imbibition: the liquid volume fraction inside the foam at the foam/porous substrate interface remains constant close to a final liquid volume fraction; (ii) intermediate imbibition: the liquid volume fraction at the interface with the porous substrate experiences a peak point and imbibition into the porous substrate is slower as compared with the drainage; (iii) slow imbibition: the liquid volume fraction at the foam/porous substrate interface increases to a maximum limiting value and a free liquid layer is formed between the foam and the porous substrate. However, the free liquid layer disappears after some time. The transition points between these three different drainage/imbibition regimes were delineated by introducing two dimensionless numbers.

Fluoro- vs hydrocarbon surfactants: why do they differ in wetting performance?

Fluorosurfactants are the most effective compounds to lower the surface tension of aqueous solutions, but their wetting properties as related to low energy hydrocarbon solids are inferior to hydrocarbon trisiloxane surfactants, although the latter demonstrate higher surface tension in aqueous solutions. To explain this inconsistency available data on the adsorption of fluorosurfactants on liquid/vapour, solid/liquid and solid/vapour interfaces are discussed in comparison to those of hydrocarbon surfactants. The low free energy of adsorption of fluorosurfactants on hydrocarbon solid/water interface should be of a substantial importance for their wetting properties.

Adsorption layer properties of alkyltrimethylammonium bromides at interfaces between water and different alkanes.

We measured the interfacial tensions of aqueous solutions against different oil phases using drop profile analysis tensiometry (PAT-1, Sinterface Technologies, Germany) for decyl- and dodecyltrimethylammonium bromide (C10TAB and C12TAB) in phosphate buffer (10 mM, pH7). The following alkanes were used as oil phases: hexane, heptane, octane, nonane, decane, dodecane and tetradecane. The obtained equilibrium interfacial tension isotherms were fitted by the Frumkin Ionic Compressibility model (FIC). The surfactants adsorb at the water/oil interface in competition with the oil molecules. At high surfactant surface coverage this competitive adsorption is manifested in two ways. First, for short chain surfactants, the oil molecules are embedded into the adsorption layer. Second, for long chain surfactants, the short alkane chains of the oil molecules are squeezed out from the adsorption layer due to strong mutual interaction between surfactants' chains.

Ionic strength and pH as control parameters for spontaneous surface oscillations.

A system far from equilibrium, where the surfactant transfer from a small drop located in the aqueous bulk to the air-water interface results in spontaneous nonlinear oscillations of surface tension, is theoretically and experimentally considered. The oscillations in this system are the result of periodically arising and terminating Marangoni instability. The surfactant under consideration is octanoic acid, the dissociated form of which is much less surface-active than the protonated form. Numerical simulations show how the system behavior can be controlled by changes in pH and ionic strength of the aqueous phase. The results of numerical simulations are in good agreement with experimental data.

Effect of water hardness on surface tension and dilational visco-elasticity of sodium dodecyl sulphate solutions.

The complementary drop and bubble profile analysis and maximum bubble pressure tensiometry are used to measure the dynamic surface tension of aqueous SDS solutions in the presence of hardness salts (CaCl(2) and MgCl(2) in the ratio of 2:1 at concentrations of 6 and 40FH). The presence of hardness salts results in an essential increase of the SDS adsorption activity, which indicates the formation of Ca(DS)(2) and Mg(DS)(2) in the SDS solutions. The surface tension isotherms of SDS in presence of Ca(DS)(2) and Mg(DS)(2) are described using the generalised Frumkin model. The presence of hardness salts accelerates the ageing of SDS solutions as compared with the addition of 0.01 M NaCl due to a faster hydrolysis and hence formation of dodecanol. These results are used to estimate the possible concentration of dodecanol in the studied SDS solutions. The buoyant bubble profile method with harmonic surface oscillations is used to measure the dilational rheology of SDS solutions in presence of hardness salts in the frequency range between 0.005 Hz and 0.2 Hz. The visco-elasticity modulus in the presence of hardness salts is higher as compared with its values in the presence of 0.01 M NaCl additions. The ageing of SDS solutions leads to an essential increase of the visco-elastic modulus.

Aggregation in colloidal suspensions: effect of colloidal forces and hydrodynamic interactions.

The forces acting in colloidal suspensions and affecting their stability and aggregation kinetics are considered. The approximations used for these forces in numerical simulations and the importance of the balanced account for both colloidal forces and hydrodynamic interactions are discussed. As an example the results of direct numerical simulations of kinetics of aggregation either with account for hydrodynamic interaction between particles or without it are compared by varying the parameters of the interaction potential between particles and fraction of solid. Simulations are based on the Langevin equations with pairwise interaction between particles and take into account Brownian, hydrodynamic and colloidal forces. It is confirmed that the neglecting of hydrodynamic interaction results in an accelerated growth of aggregates. The results of numerical simulations of aggregation kinetics are compared with well known analytical solutions.

Dynamics of interfacial layers-experimental feasibilities of adsorption kinetics and dilational rheology.

Each experimental method has a certain range of application, and so do the instruments for measuring dynamic interfacial tension and dilational rheology. While the capillary pressure tensiometry provides data for the shortest adsorption times starting from milliseconds at liquid/gas and tens of milliseconds at liquid/liquid interfaces, the drop profile tensiometry allows measurements in a time window from seconds to many hours. Although both methods together cover a time range of about eight orders of magnitude (10(-3) s to 10(5) s), not all surfactants can be investigated with these techniques in the required concentration range. The same is true for studies of the dilational rheology. While drop profile tensiometry allows oscillations between 10(-3) Hz and 0.2 Hz, which can be complemented by measurements with capillary pressure oscillating drops and the capillary wave damping method (up to 10(3) Hz) these six orders of magnitude in frequency are often insufficient for a complete characterization of interfacial dilational relaxations of surfactant adsorption layers. The presented analysis provides a guide to select the most suitable experimental method for a given surfactant to be studied. The analysis is based on a diffusion controlled adsorption kinetics and a Langmuir adsorption model.

Auto-oscillation of surface tension: effect of pH on fatty acid systems.

Spontaneous nonlinear oscillations of surface tension produced by transfer of either octanoic or nonanoic acids from a droplet situated in the bulk water to the air/water interface are studied experimentally. It is shown that the oscillation amplitude decreases significantly with the increase of pH of aqueous phase. At pH > 6.5, detectable oscillations for the two fatty acids studied do not exist. The results are discussed in terms of the mechanism proposed recently for spontaneous oscillations produced by transfer of nonionic surfactants.

Recognition and dissociation kinetics in the interfacial molecular recognition of barbituric acid by amphiphilic melamine-type monolayers.

Progress in the understanding of interfacial molecular recognition kinetics is obtained by use of the sweeping technique for experimental studies of the reaction kinetics between a host monolayer and a non-surface-active species dissolved in the aqueous subphase. The experimental results show that the interfacial recognition reaction between a 2C(11)H(23)-melamine (2,4-di(n-undecylamino)-6-amino-1,3,5-triazine) monolayer and dissolved barbituric acid is reversible when the 2C(11)H(23)-melamine/barbituric acid monolayer is transferred back onto a pure water subphase. The kinetics of the recognition and dissociation reaction is experimentally and theoretically investigated. The approximate additive theoretical model developed recently is extended to consider the dissociation kinetics of the interfacial supramolecular complex. The kinetic constants for the recognition and dissociation reactions in the mixed monolayer consisting of 2C(11)H(23)-melamine and 2C(11)H(23)-melamine/barbituric acid complex are determined. It is shown that the kinetic constant of the recognition reaction is nearly independent of temperature, whereas that of the dissociation reaction increases with increasing temperature.