In vitro activity of thiamphenicol against Haemophilus influenzae, Streptococcus pneumoniae and Streptococcus pyogenes clinical isolates

Objective. To determine in vitro activity of thiamphenicol and other clinically available antimicrobials against clinical isolates of Haemophilus influenzae, Streptococcus pneumoniae and Streptococcus pyogenes. Materials and Methods. We included in the study 875 clinical isolates from 20 Russian cities during 2018–2019. Among tested strains, 126 were H. influenzae, 389 – S. pneumoniae, 360 – S. pyogenes. Antimicrobial susceptibility testing was performed using broth microdilution method according to ISO 20776-1:2006. AST results were interpreted according to EUCAST v.11.0 clinical breakpoints. Results. The minimum inhibitory concentrations (MICs) of thiamphenicol did not exceed 2 mg/L for 94.4% of H. influenzae strains (MIC50 and MIC90 were 0.5 and 1 mg/L, respectively). Thiamphenicol was active against 76.9% of ampicillin-resistant H. influenzae strains (MIC of thiamphenicol 0.06 mg/L) did not exceed 2 mg/L. A total of 88.1% of S. pneumoniae strains resistant to erythromycin were highly susceptible to thiamphenicol (MIC < 2 mg/L). The MIC of thiamphenicol did not exceed 8 mg/L for 96.1% of S. pyogenes strains (MIC50 and MIC90 were 2 and 4 mg/L, respectively). Conclusions. Thiamphenicol was characterized by relatively high in vitro activity, comparable to that of chloramphenicol, against tested strains of H. influenzae, S. pneumoniae and S. pyogenes, including S. pneumoniae isolates with reduced susceptibility to penicillin

Characteristics and in vitro response of thin hydroxyapatite-titania films produced by plasma electrolytic oxidation of Ti alloys in electrolytes with particle additions

The enhancement of the biological properties of Ti by surface doping with hydroxyapatite (HA) is of great significance, especially for orthodontic applications. This study addressed the effects of HA particle size in the electrolyte suspension on the characteristics and biological properties of thin titania-based coatings produced on Ti–6Al–4V alloy by plasma electrolytic oxidation (PEO). Detailed morphological investigation of the coatings formed by a single-stage PEO process with two-step control of the electrical parameters was performed using the Minkowski functionals approach. The surface chemistry was studied by glow discharge optical emission spectroscopy and Fourier transform infrared spectroscopy, whereas mechanical properties were evaluated using scratch tests. The biological assessment included in vitro evaluation of the coating bioactivity in simulated body fluid (SBF) as well as studies of spreading, proliferation and osteoblastic differentiation of MC3T3-E1 cells. The results demonstrated that both HA micro- and nanoparticles were successfully incorporated in the coatings but had different effects on their surface morphology and elemental distributions. The micro-particles formed an irregular surface morphology featuring interpenetrated networks of fine pores and coating material, whereas the nanoparticles penetrated deeper into the coating matrix which retained major morphological features of the porous TiO2 coating. All coatings suffered cohesive failure in scratch tests, but no adhesive failure was observed; moreover doping with HA increased the coating scratch resistance. In vitro tests in SBF revealed enhanced bioactivity of both HA-doped PEO coatings; furthermore, the cell proliferation/morphometric tests showed their good biocompatibility. Fluorescence microscopy revealed a well-organised actin cytoskeleton and focal adhesions in MC3T3-E1 cells cultivated on these substrates. The cell alkaline phosphatase activity in the presence of ascorbic acid and β-glycerophosphate was significantly increased, especially in HA nanoparticle-doped coatings

COMPARATIVE EFFICACY OF CETIRIZINE GENERIC (MANUFACTURED BY EGIS, HUNGARY) AND ORIGINAL IN THE FORM OF DROPS IN COMPLEX TREATMENT OF ATOPIC DERMATITIS IN INFANTS

The article compares the efficacy of two medications containing cetirizine in the form of drops in treating atopic dermatitis in 6–24 months old children. It is shown that the use of both medications in complex treatment of atopic dermatitis children helps achieve a fast clinical effect. Cetirizine generic is no less effective than the original one in treatment of atopic dermatitis in children and is well accepted by the patients.Key words: atopic dermatitis, children, treatment, cetirizine.</strong

COMPARATIVE EFFICACY OF CETIRIZINE GENERIC (MANUFACTURED BY EGIS, HUNGARY) AND ORIGINAL IN THE FORM OF DROPS IN COMPLEX TREATMENT OF ATOPIC DERMATITIS IN INFANTS

The article compares the efficacy of two medications containing cetirizine in the form of drops in treating atopic dermatitis in 6–24 months old children. It is shown that the use of both medications in complex treatment of atopic dermatitis children helps achieve a fast clinical effect. Cetirizine generic is no less effective than the original one in treatment of atopic dermatitis in children and is well accepted by the patients.Key words: atopic dermatitis, children, treatment, cetirizine

AMRexpert – online platform for interpretation, verification and validation of antimicrobial susceptibility testing

Objective. To review the key principles and functionality of AMRexpert online platform. Materials and Methods. The information part of the platform is comprised of rules based on the EUCAST recommendations and various standards for interpreting the results of antimicrobial susceptibility testing (EUCAST, CLSI versions 2020-2022). The technical part of the platform was developed using C# programming language, Angular and Bootstrap frameworks. AST results of Serratia marcescens, Pseudomonas aeruginosa, Staphylococcus saprophyticus, Enterococcus faecium specific isolates were analyzed for practical testing of the platform using EUCAST v.12.0, 2022 interpretation criteria. Results. The developed platform for the evaluation of microbiological reports includes a wide list of expert rules, various standards for the interpretation of the AST results. Consistent data input, the ability to switch forms between several microorganisms, and the presentation of evaluation results in the form of blocks allows all necessary information to be structured. Practical use of the platform is available for various infectious pathogens. Fast and efficient interaction between users is provided by different options for sharing and saving the results. Conclusions. The web-based application evaluates microbiological reports in a comprehensive approach, with the ability to apply the results later to prescribe antimicrobial therapy. The platform for the interpretation, verification and validation of the AST results – AMRexpert can be accessed at https://amrexpert.ru

Mechanical properties of decellularized extracellular matrix coated with TiCaPCON film

For the first time the surface of decellularized extracellular matrix (DECM) was modified via deposition of a multicomponent bioactive nanostructured film for improvement of the DECM's mechanical properties. TiCaPCON films were deposited onto the surface of intact and decellularized ulna, radius, and humerus bones by magnetron sputtering of TiC<SUB>0.5</SUB> + 10%Ca<SUB>3</SUB>(PO<SUB>4</SUB>)<SUB>2</SUB> and Ti targets in a gaseous mixture of Ar + N<SUB>2</SUB>. The film structure was studied using x-ray diffraction, scanning and transmission electron microscopy, and Raman spectroscopy. The films were characterized in terms of their wettability, as well as adhesion strength to the intact bone and DECM substrates. The mechanical properties of TiCaPCON-coated samples were investigated by compression testing. In addition, humerus bones were evaluated during three-point bending tests. The results indicate that the tightly adhered films, uniformly covering the DECM surfaces, possessed hydrophilic characteristics. A maximum improvement in mechanical properties (250%) was observed for coated humerus samples. In case of decellularized radius bones, the compressive strength also increased by 150% after coating. The positive role of TiCaPCON films was less noticeable for ulna bones because of large data scattering. These results clearly indicate that the films acted as a rigid frame that increased the material compressive strength. Compared with intact bones, fracture in the TiCaPCON-coated DECM samples was characterized by rarer and larger cracks generated under higher critical loads. As a result, the samples were crushed into several large pieces and numerous tiny fragments. Although the film deposition increased the bone stiffness, the bending tests revealed that the flexural strength of the coated samples became 20%–25% lower than the strength of the film-free samples

Synthesis of boron nitride nanostructures from borates of alkali and alkaline earth metals

International audienceReactions of borates of alkali and alkaline earth metals with ammonia in a temperature range of 950-1250 °C are explored with respect to the nano-boron nitride syntheses. M 2 O(MO)·nB 2 O 3 borates, where M 2 = Li, Na, K, and M = Mg, Ca, Sr, Ba are studied for a molar ratio n = 0.5-5.0. It is found that various boron nitride (BN) nanostructures such as BN-nanotubes (BNNTs), graphene-like BN petals (BNGPs), and columnar porous BN (BNP) flakes grow depending on the borate composition and synthesis temperature. Both morphology and yield of BN-nanostructures depend on the basicity of the metal oxide and its fraction in the precursor borate. Borates of Li, Mg, and Ca demonstrate the highest ability to produce BNNTs. Borates of Na and K produce BNGPs in the whole range of investigated n values and temperatures. BNP flakes with pores of 10-100 nm are formed from Mg-borates with n andgt; 3. © 2015 The Royal Society of Chemistry

Growth of spherical boron oxynitride nanoparticles with smooth and petalled surfaces during a chemical vapour deposition process

International audienceA rich variety of hollow and solid (without internal hollow spaces) spherical boron oxynitride nanoparticles (BNO-NPs) with smooth or petalled surfaces were synthesized during a boron oxide-assisted chemical vapour deposition (BOCVD) process. Diverse BNO-NPs were obtained while utilizing different precursors, gas flow rates and synthesis temperatures in the range of 1200-1430 °C. The BNO-NP morphologies, atomic structures and spatially-resolved chemical compositions were studied by scanning (SEM) and transmission electron microscopy (TEM), X-ray diffraction (XRD), energy-dispersive X-ray, Fourier-transform infrared and confocal Raman spectroscopy. Particle size distributions were measured using dynamic light scattering under visual microscopic control. A growth model of different spherical BNO-NP types based on the detailed analysis of physical-chemical processes at different BOCVD stages was proposed. A new type of spherical BNO-NPs of "hedgehog" morphologies with BN nanowires on their surfaces was first predicted in accordance with the designed model and then experimentally verified. © 2016 The Royal Society of Chemistry

Synthesis of boron nitride nanostructures from borates of alkali and alkaline earth metals

Reactions of borates of alkali and alkaline earth metals with ammonia in a temperature range of 950-1250 °C are explored with respect to the nano-boron nitride syntheses. M 2 O(MO)·nB 2 O 3 borates, where M 2 = Li, Na, K, and M = Mg, Ca, Sr, Ba are studied for a molar ratio n = 0.5-5.0. It is found that various boron nitride (BN) nanostructures such as BN-nanotubes (BNNTs), graphene-like BN petals (BNGPs), and columnar porous BN (BNP) flakes grow depending on the borate composition and synthesis temperature. Both morphology and yield of BN-nanostructures depend on the basicity of the metal oxide and its fraction in the precursor borate. Borates of Li, Mg, and Ca demonstrate the highest ability to produce BNNTs. Borates of Na and K produce BNGPs in the whole range of investigated n values and temperatures. BNP flakes with pores of 10-100 nm are formed from Mg-borates with n andgt; 3. © 2015 The Royal Society of Chemistry

Boron Nitride Nanoparticles with a Petal-Like Surface as Anticancer Drug-Delivery Systems

International audienceNanoparticles (NPs) have a great potential as nanosized drug-delivery carriers. Such systems must safely deliver the drug to the site of the tumor without drug leakage, effectively penetrate inside cancer cells, and provide intracellular drug release. Herein we developed an original and simple method aimed at the fabrication of spherical boron nitride NPs (BNNPs), 100-200 nm in diameter, with peculiar petal-like surfaces via chemical vapor deposition. Such structures were found to be able to absorb a large amount of antitumor drug-killing tumor cells. They revealed low cytotoxicity and rapid cellular uptake. BNNPs were saturated with doxorubicin (DOX) and then dispersed. The BNNPs loaded with DOX (BNNPs-DOX) were stable at neutral pH but effectively released DOX at pH 4.5-5.5. MTT assay and cell growth testing showed that the BNNPs-DOX nanocarriers had been toxic for IAR-6-1 cells. BNNPs loaded with DOX penetrated into the neoplastic IAR-6-1 cells using endocytic pathways, and then DOX released into the cytoplasm and cell nuclei and resulted in cell death. © 2015 American Chemical Society