Keplerate {Mo132}-Stearic Acid Conjugates: Supramolecular Synthons for the Design of Dye-Loaded Nanovesicles, Langmuir-Schaefer Films, and Infochemical Applications.

Self-assembly gives rise to the versatile strategies of smart material design but requires precise control on the supramolecular level. Here, inorganic-organic synthons (conjugates) are produced by covalently grafting stearic acid tails to giant polyoxometalate (POM) Keplerate-type {Mo132} through an organosilicon linker (3-aminopropyltrimethoxysilane, APTMS). Using the liposome production approach, the synthons self-assemble to form hollow nanosized vesicles (100-200 nm in diameter), which can be loaded with organic dyes─eriochrome black T (ErChB) and fluorescein (FL)─where the POM layer serves as a membrane with subnanopores for cell-like communication. The dye structure plays an essential role in embedding dyes into the vesicle's shell, which opens the way to control the colloidal stability of the system. The produced vesicles are moved by an electric field and used for the creation of an infochemistry scheme with three types of logic gates (AND, OR, and IMP). To design 2D materials, synthons can form spread films, from simple addition on the water-air interface to lateral compression in the Langmuir bath, and highly ordered structures appear, demonstrating electron diffraction in Langmuir-Schaefer (LS) films. These results show the significant potential of POM-based synthons and nanosized vesicles to supramolecular design the diversity of smart materials.

Sorption-oxidation mechanism for the removal of arsenic (III) using Cu-doped ZnO in an alkaline medium.

1-D oxides Zn1-xCuxO and spherical composites Zn1-xCuxO/CuO were obtained by thermolysis of formate-glycolate complexes Zn1-xCux (HCOO)(OCH2CH2O)1/2 (0 ≤ x ≤ 0.15). The structural and property characteristics showed that Cu was introduced into the Zn site of the ZnO lattice to form the Zn0.95Cu0.05O solid solution. The concentration of copper in the precursors regulates the topological and structural features of the formation of Zn1-xCuxO oxides, which determine their sorption and photocatalytic properties. The materials were tested in As3+ photooxidation reaction under UV and visible radiation. It has been established that Cu+ is an effective dopant in the composition of 1-D oxide Zn1-xCuxO (0 ≤ x < 0.1). The presence of Cu2+ in the shell of Zn1-xCuxO/CuO composite reduces the photoactivity of the material. The maximum efficiency of arsenic extraction (up to 80% for Zn0.95Cu0.05O) was achieved from dilute arsenic-containing solutions (3.8 mg/L As) and an adsorbent concentration of 0.8 g/L for 24 h. In saturated solutions (380 mg/L As) this value is reduced by a factor of 100. According to XPS data, the primary process is As3+ sorption on the catalyst surface followed by its oxidation to As5+. Using the EPR method it was found that singly charged oxygen vacancies V O + $$ {V}_O^{+} $$ associated with Cu in Zn1-xCuxO are directly involved in the photostimulated oxidation of As3+. PRACTITIONER POINTS: Two types of Zn1-x Cux O photocatalysts were obtained by thermolysis of the Zn1-x Сux (HCOO)(OCH2 CH2 O)1/2 complex (0 ≤ x ≤ 0.15) in air. Sorption of arsenic from dilute solutions reaches 80% on 1-D oxide Zn0.95 Cu0.05 O. Sorption of As3+ on the catalyst surface is at primary process followed by its oxidation to As5+ . Removal of As3+ from alkaline solutions occurs due to successful combination of sorption and photocatalytic properties of the 1-D oxides Zn1-x Cux O.

Production of Graft Copolymers of Cod Collagen with Butyl Acrylate and Vinyl Butyl Ether in the Presence of Triethylborane-Prospects for Use in Regenerative Medicine.

Collagen is a suitable material for regenerative medicine because it is characterized by its good biocompatibility. However, due to its fibrillar structure, it cannot organize itself into three-dimensional porous structures without additional modification. The introduction of synthetic monomer elements into the collagen macromolecules is a technique used to form three-dimensional, collagen-based, branched, and crosslinked structures. New types of graft copolymers made from cod collagen with a butyl acrylate and vinyl butyl ether copolymer in aqueous dispersion were obtained in the presence of triethylborane by a radical mechanism. The process of graft copolymer formation proceeded as usual by radical initiation, through radicals formed during triethylborane oxidation by oxygen residues, collagen borination, and reversible inhibition with the participation of a boroxyl radical. The characteristics of the graft copolymers were determined using methods of physical and chemical analysis (GPC, SEM, IR spectroscopy, etc.), while the cytotoxicity was assessed using the MTT assay method. It is shown that the grafting of alternating blocks of butyl acrylate and vinyl butyl ether to the protein macromolecules results in changes in the morphological pattern of the graft co-polymer in comparison with native collagen. This is manifested in the development of consolidations around the collagen fibers of the structural matrices, with the co-polymer cellular structure consisting of interpenetrating pores of unequal size. Additionally, it is important that the graft co-polymer solutions are not toxic at a certain concentration. The above properties confirm the promising nature of the technique's application as the basis for producing new materials for regenerative medicine.

The Trend, Characteristics and Treatment Outcomes in Patients with Tuberculosis Undergoing Thoracic Surgery in the Kyrgyz Republic between 2017 and 2021.

Surgery has played an important role in managing complicated tuberculosis in former Soviet Union countries, including the Kyrgyz Republic. However, published information is limited. This study aimed to document the trend, characteristics and outcomes of tuberculosis patients who underwent thoracic surgery, using routinely collected data. Between 2017 and 2021, 4-7% of tuberculosis patients in the Kyrgyz Republic underwent thoracic surgery in two centres in Bishkek and Osh. In 2021, case records were retrieved in 264 (78%) of 340 patients undergoing thoracic surgery in the country. The most common indications for surgery were pleural exudate/empyema in 127 (44%) and tuberculoma in 83 (32%). Most patients (73%) underwent surgery within 30 days of starting TB treatment. Two-thirds of patients underwent radical surgery, and surgical outcomes were excellent in 99% of patients with one death. Post-operatively, 63 (23%) patients had no TB detected by the histology, with the two most common specified conditions being lung cancer and pulmonary hydatid disease. TB treatment was stopped in these patients. Of the 201 patients with confirmed TB after surgery, TB-treatment success was documented in 163 (81%), died/failure/lost to follow-up in 10 (5%) and not evaluated in 28 (14%). This study shows that thoracic surgery is feasible, safe and effective in the routine programme setting. Recommendations are made to strengthen referral and monitoring systems.

Scaffold Chemical Model Based on Collagen-Methyl Methacrylate Graft Copolymers.

Polymerization of methyl methacrylate (MMA) in aqueous collagen (Col) dispersion was studied in the presence of tributylborane (TBB) and p-quinone: 2,5-di-tert-butyl-p-benzoquinone (2,5-DTBQ), p-benzoquinone (BQ), duroquinone (DQ), and p-naphthoquinone (NQ). It was found that this system leads to the formation of a grafted cross-linked copolymer. The inhibitory effect of p-quinone determines the amount of unreacted monomer, homopolymer, and percentage of grafted poly(methyl methacrylate) (PMMA). The synthesis combines two approaches to form a grafted copolymer with a cross-linked structure-"grafting to" and "grafting from". The resulting products exhibit biodegradation under the action of enzymes, do not have toxicity, and demonstrate a stimulating effect on cell growth. At the same time, the denaturation of collagen occurring at elevated temperatures does not impair the characteristics of copolymers. These results allow us to present the research as a scaffold chemical model. Comparison of the properties of the obtained copolymers helps to determine the optimal method for the synthesis of scaffold precursors-synthesis of a collagen and poly(methyl methacrylate) copolymer at 60 °C in a 1% acetic acid dispersion of fish collagen with a mass ratio of the components collagen:MMA:TBB:2,5-DTBQ equal to 1:1:0.015:0.25.

Coagulation removal of nickel (II) ions by ferric chloride: Efficiency and mechanism.

Removal of heavy metal ions, in particular, divalent nickel ions from natural and wastewater, is of great importance for the environment. Nickel (II) ions are very toxic and provoke many diseases. The purpose of this work was to study the possibility of removing toxic nickel (II) ions from polluted water using an iron (III) chloride (FeCl3) coagulant. It is shown that the removal of nickel ions from aqueous solution by iron (III) hydroxide precipitate formed during the coagulation process at pH 7 and 8 is described with satisfactory accuracy by the classical adsorption isotherms of Freundlich, Langmuir, and Dubinin-Radushkevich. The studies performed with the use of X-ray powder diffraction and thermal analyses, IR, Raman, and Mössbauer spectroscopy have shown that the uptake of nickel ions by iron (III) hydroxide precipitate is due to simple physical adsorption and is not accompanied by the formation of mixed iron and nickel compounds. No alloying of the formed iron (III) hydroxide precipitate with nickel ions takes place either. The formed iron (III) hydroxide precipitate is a two-line ferrihydrite having the gross formula Fe2 O3 × 3H2 O. Its sorption capacity for nickel ions is almost an order of magnitude higher than that of some mineral and carbon sorbents, and at pH 7 and 8, it is 60.5 and 141.9 mg/g, respectively. PRACTITIONER POINTS: Coagulant FeCl3 cleans contaminated solutions from Ni(II) ions. Iron (III) hydroxide precipitated at pH 7 and 8 is a two-line ferrihydrite Fe2 O3  × 3H2 O. Removing of Ni(II) ions is described by classical adsorption isotherms. The most complete removal of Ni(II) ions occurs at pH = 8.

Graft Polymerization of Acrylamide in an Aqueous Dispersion of Collagen in the Presence of Tributylborane.

Graft copolymers of collagen and polyacrylamide (PAA) were synthesized in a suspension of acetic acid dispersion of fish collagen and acrylamide (AA) in the presence of tributylborane (TBB). The characteristics of the copolymers were determined using infrared spectroscopy and gel permeation chromatography (GPC). Differences in synthesis temperature between 25 and 60 °C had no significant effect on either proportion of graft polyacrylamide generated or its molecular weight. However, photomicrographs taken with the aid of a scanning electron microscope showed a breakdown of the fibrillar structure of the collagen within the copolymer at synthesis temperatures greater than 25 °C. The mechanical properties of the films and the cytotoxicity of the obtained copolymer samples were studied. The sample of a hybrid copolymer of collagen and PAA obtained at 60 °C has stronger mechanical properties compared to other tested samples. Its low cytotoxicity, when the monomer is removed, makes materials based on it promising in scaffold technologies.

Exciton Luminescence and Optical Properties of Nanocrystalline Cubic Y2O3 Films Prepared by Reactive Magnetron Sputtering.

This paper presents a comprehensive study of the energy structure, optical characteristics, and spectral-kinetic parameters of elementary excitations in a high-purity nanocrystalline cubic Y2O3 film synthesized by reactive magnetron sputtering. The optical transparency gaps for direct and indirect interband transitions were determined and discussed. The dispersion of the refractive index was established based on the analysis of interference effects. It was found that the refractive index of the Y2O3 film synthesized in this study is higher in order of magnitude than that of the films obtained with the help of other technologies. The intrinsic emission of Y2O3 film has been discussed and associated with the triplet-singlet radiative relaxation of self-trapped and bound excitons. We also studied the temperature behavior of the exciton luminescence of Y2O3 for the first time and determined thermal activation barriers. The optical energy and kinetic parameters of cubic Y2O3 films were analyzed in comparison with those of the monoclinic films of yttrium oxide. The main difference between the optical properties of cubic and monoclinic Y2O3 films was established, which allowed for a supposition of their application prospects.

Grafting of Methyl Methacrylate onto Gelatin Initiated by Tri-Butylborane-2,5-Di-Tert-Butyl-p-Benzoquinone System.

Graft gelatin and poly(methyl methacrylate) copolymers were synthesized in the presence of the tributylborane-2,5-di-tert-butyl-p-benzoquinone (2,5-DTBQ) system. The molecular weight parameters and morphology of the polymer indicate that it has a cross-linked structure. Obtained data confirm the simultaneous formation of a copolymer in two ways: "grafting from" and "grafting to". It leads to the cross-linked structure of a copolymer. This structure was not obtained for copolymers synthesized in the presence of other initiating systems: azobisisobutyronitrile; tributylborane; azobisisobutyronitrile and tributylborane; azobisisobutyronitrile, tributylborane, and 2,5-di-tert-butyl-p-benzoquinone. In these cases, the possibility of the formation of the copolymer, simultaneously in two ways, was excluded. Graft gelatin and poly(methyl methacrylate) copolymers synthesized in the presence of the tributylborane-2,5-di-tert-butyl-p-benzoquinone system are promising in terms of their use in scaffold technologies due to the three-dimensional mesh structure, providing a high regenerative potential of materials.

Biomarkers in PTSD-susceptible and resistant veterans with war experience of more than ten years ago: FOCUS ON cortisol, thyroid hormones, testosterone and GABA.

In the present study we measured the concentrations of cortisol, thyroid hormones, testosterone, and GABA (gamma aminobutyric acid) in am blood plasma samples of combatants with an at least 10 year history of military psychological trauma (N = 74) divided in groups that either suffer from post-traumatic stress disorder (PTSD) (N = 37) or are resistant (N = 37) as well as in a control group without traumatic experience in the anamnesis, (N = 34). PTSD symptoms were assessed using the Clinician-Administered PTSD Scale (CAPS). The results show that the am blood cortisol levels of individuals that were exposed to war zone experiences irrespective susceptibility for or resistance to PTSD were significantly higher than the values observed in the controls. Testosterone levels in PTSD patients differed neither from that observed in PTSD resistant nor control groups. In the resistant group testosterone levels were however significantly higher than in controls. The level of all thyroid hormones did not differ between the study groups. GABA level was significantly lower in the PTSD group compared with healthy controls. In the resistant group blood GABA levels were not significantly different from either PTSD patients or controls. In conclusion, the current data show that cortisol and to some extent testosterone may serve as biomarker of war zone stress per se, even if trauma was experienced at least ten years before, rather than of only PTSD or resistance to PTSD. GABA, in contrast, can be considered a potential marker of the protracted nature of PTSD.

Self-Assembly of Ag2S Colloidal Nanoparticles Stabilized by MPS in Water Solution.

Self-assembly of colloidal Ag2S nanoparticles (NPs) was studied in the presence of (3-mercaptopropyl)trimethoxysilane (MPS). Solutions with different molar ratios of Ag2S/MPS were prepared. The appearance of nano- and microtubes was detected. Self-organized NPs were studied with optical microscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and high-resolution transmission electron microscopy (HRTEM). Silicon nuclear magnetic resonance spectroscopy (29Si NMR) was used to study polycondensation of MPS molecules. Geometrical parameters of the nano- and microtubes depended on the molar ratio of Ag2S/MPS. The scheme and mechanism of self-assembly of Ag2S NPs in nanotubes in the presence of MPS were proposed. The effect of MPS on the preservation of the initial stoichiometry of Ag2S NPs was discussed.

Enzymatic Hydrolysis of Marine Collagen and Fibrinogen Proteins in the Presence of Thrombin.

: Enzymatic hydrolysis of native collagen and fibrinogen was carried out under comparable conditions at room temperature. The molecular weight parameters of proteins before and after hydrolysis by thrombin were monitored by gel-penetrating chromatography (GPC). An analysis of the experiment results shows that the molecular weight parameters of the initial fibrinogen (Fn) and cod collagen (CC) are very similar. High molecular CC decays within the first minute, forming two low molecular fractions. The main part (~80%) falls on the fraction with a value of Mw less than 10 kDa. The initial high molecular fraction of Fn with Mw ~320-340 kDa is not completely hydrolyzed even after three days of control. The presence of low molecular fractions with Mw ~17 and Mw ~10 kDa in the solution slightly increases within an hour and noticeably increases for three days. The destruction of macromolecules of high molecular collagen to hydrolysis products appears almost completely within the first minute mainly to the polymer with Mw ~10 kDa, and enzymatic hydrolysis of fibrinogen proceeds slower than that of collagen, but also mainly to the polymer with Mw ~10 kDa. Comparative photos of the surfaces of native collagen, fibrinogen and the scaffold based on them were obtained.

Immunological outcomes in infants with ROP after dexamethasone and aminophylline.

This research aims to improve anaesthesia services given to preterm infants by the use of dexamethasone and aminophylline administrated under sevoflurane, and to analyze its effect on the cell-mediated immunity (CD4+CD25+Foxp3+(T-reg) and CD4+CD25highFoxp3+CD127low). We have examined 74 premature babies with retinopathy of prematurity (ROP) at the 3-5 stages during the 25-32 week gestation period (1-6 months after birth). Both immunomodulators had no significant effect on clinical parameters after one dose (P > .05). Aminophylline (2.4% solution, 0.1 mL/kg or 0.132 mL per infant on average) and dexamethasone (0.4% solution, 0.1 mg/kg or 0.132 mL per infant on average) were intravenously injected 15 minutes before the end of the surgery. Required anaesthesia depth was maintained with inhalation anaesthetic (1.5-2.0 IAC), and the minimum fresh gas flow was not less than 2 L. Blood samples were taken from the vein (anaesthesia induction stage) into the tubes containing EDTA (the anticoagulant), stored at 20-25°C, and then, processed and stained within 24 hours after sampling. Both immunomodulators had no significant effect on clinical parameters after one dose (P > .05). Short-term shift in regulatory T-cell level affected by dexamethasone has a negative effect combined with further withdrawal effect that this hormonal drug has. Aminophylline has such clinical effects as improving pulmonary ventilation, decrease in apnoea frequency, and improving blood gas indices. Aminophylline has less expressed but more prolonged positive effect during the day when used for several days. It may lead to a persistent positive effect with progressive treatment outcomes.

Kinetic selection of nonradiative excitation in photonic nanoparticles Gd2O3:Er.

In the present work, we separate and classify four different pathways for UV-vis energy conversion with participation of Gd3+def and Er3+ ions located at dissimilar structural sites in the Gd2O3 lattice. The Gd3+def centers represent host cations with a distorted environment due to the nearest defects of the anionic sublattice. Two non-equivalent types of both Gd3+def donor and Er3+ acceptor centers occupying C2 and S6 structural sites are selected in Gd2O3:Er nanoparticles by the spectral-kinetic method. Such structural features provide the realization of several parallel channels of nonradiative Gd3+def→ Er3+ energy migration and lead to a multimodal distribution of emission centers over the lifetime of the Er3+ excited states. The widths and the maxima of the kinetic parameter distributions depend on the degree of disorder in the nearest environment of Gd3+def donor centers. Our data show the possibility of practical realization of what is regarded as an additional pathway for the enhancement of excitation nonradiative transport in photonic devices.