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Using the method of the joint crystallization of solutions of nitrate salts with ultrasonic treatment, xerogels and highly dispersed mesoporous powders of the following composition are synthesized: (CeO2)1 – x(Nd2O3)x (x = 0.02; 0.05; 0.10), Gd1 – xSrxCo0.5O3 – δ (x = 0.1, 0.15, 0.2, 0, 25), Gd0.4Sr0.1Ni0.5O3 – δ, and Gd0.125La0.125Sr0.25Co0.5O3 – δ; and based on them, nanoceramic materials with a crystalline cubic structure of the fluorite type, as well as an orthorhombic and tetragonal structure of the perovskite type with CSR ~ 55–90 nm (1300°С), respectively, are obtained. The physicochemical properties of the resulting ceramics are studied; it is revealed that it has an open porosity of 7–11% for the composition (CeO2)1 – x(Nd2O3)x and 17–42% for materials with the Gd1 – xSrxCo0.5O3 – δ, Gd0.4Sr0.1Ni0.5O3 – δ, and Gd0.125La0.125Sr0.25Co0.5O3 – δ composition. Materials based on cerium oxide predominantly have the ionic (ion transport numbers ti = 0.71–0.89 in the range 300–700°С) type of electrical conductivity due to the formation of mobile oxygen vacancies in the heterovalent substitution of Ce4+ by Nd3+; and σ700°С = 0.31 × 10–2 S/cm Solid solutions based on nickelate and lanthanum cobaltite have mixed electron-ionic conductivity, σ700°С = 0.59 × 10–1 S/cm with transfer numbers te = 0.92–0.99 and ti = 0.08–0.01. The prospects for using the obtained ceramic materials as solid oxide electrolytes and electrodes for medium-temperature fuel cells (FCs) are shown. [ABSTRACT FROM AUTHOR]

This article describes the production of nanodisperse xerogel and powders (average CSR size of 9 nm) in the ZrO2–Y2O3–Al2O3 system by coprecipitation of hydroxides. A strong highly porous ceramic has been produced from the initial powder with the composition of [(ZrO2)0.97(Y2O3)0.03]0.8(Al2O3)0.2 with pore forming additives using patented solid phase sintering. Using Doppler sonography, the volume of blood flow in arteriolas and capillaries has been estimated 150 and 250 days after implantation of plates. Therefore, the microcirculatory Doppler sonography seems to be a promising intravital method of estimating blood flow in the zone of plates from biocompatible nonresorbable material and, probably, inside the plates. It has been found that the ceramic plates based on zirconium dioxide in the body of experimental animals do not result in a negative reaction of animal's body. The in vivo experimental results make it possible to state that the obtained bioceramic based on zirconium dioxide is a promising material for endoprosthetics. [ABSTRACT FROM AUTHOR]

By the joint crystallization of solutions of nitrate salts, fine powders of La1 – xSrxNiO3, La1 ‒xSrx-CoO3, and La1 –xSrxFe0.7Ni0.3O3 (x = 0.30 and 0.40) are synthesized. They have a specific pore volume of 0.018–0.035 cm3/g and a specific surface area of 15–31 m2/g. On their basis, ceramic nanomaterials of a given composition with CSR ~ 64–70 nm (1300°С) are obtained. The physicochemical properties of the obtained ceramic are studied; it is revealed that the ceramic is a solid solution with open porosity in a range of 17–30% and a high value of the relative density of 94%. In terms of their physicochemical properties (open porosity, density, coefficient of thermal expansion), the obtained ceramic materials are promising as solid oxide cathodes for intermediate-temperature fuel cells. [ABSTRACT FROM AUTHOR]

Mesoporous nanosized aerogels, xerogels, and powders in the ZrO2–Y2O3–CeO2 and ZrO2‒Y2O3–Al2O3 systems have been obtained by liquid-phase synthesis methods. The thermolysis, phase composition, and textural features of the synthesized materials have been studied. It has been found that the predominance of Lewis acid sites (LASs) on the surface of their particles indicates its lower hydroxylation and, as a consequence, a lower degree of agglomeration of the obtained materials. [ABSTRACT FROM AUTHOR]

Isoniazid concentrations were measured in the serum, liver, and lungs of the animals 1, 3, 6, and 24 hours after administration of isoniazid in a dose of 10 mg/kg via various routes (orally, intramuscularly, and lymphotropically--into the pretracheal cellular space) guinea-pig blood and organs in the experiment on 36 guinea-pigs. Within the first 1-3 hours after intramuscular injection of isoniazid, its concentrations in the serum and lungs were higher than those with other routes of administration. With lymphotropic and oral routes, the levels of the drug were very similar in all the studied media in the first 6 hours, but later its hepatic accumulation after lymphotropic administration proved to be considerably lower than via other routes. The lymphotropic injection of isoniazid provides its therapeutic concentrations in the blood and in the lung and simultaneously creates prerequisites for reducing the incidence and severity of hepatotoxic adverse reactions.

A trial entered 136 patients with active tuberculosis of the lungs. 86 patients received conventional chemotherapy and a course of microwave therapy. Control patients received chemotherapy alone. Phagocyte cell viability and NB-test served as assessment laboratory criteria. Millimetric waves in the treatment of pulmonary tuberculosis potentiate the treatment efficacy documented as more rapid infiltration resolution and cavern closure through the mechanism of normalization of phagocyte cell function. The choice of wave length is principal: 5.6 mm waves affect phagocyte function negatively, 6.4 mm waves produce more significant positive effect in young patients with new local lesions while 7.1 mm waves in older patients and in severe involvement. In vitro radiation of the patients' blood using different wave lengths and subsequent performance of NB-test provides objective information for choice of optimal treatment regimen.

NBT test basal values and those after cell stimulation with killed BCG culture were measured by spectrophotometry in alveolar macrophages isolated from bronchoalveolar lavage fluid, in peripheral blood neutrophils and monocytes of 49 patients with newly detected pulmonary tuberculosis. Stimulation coefficient was estimated as the ratio of induced to spontaneous NBT-test values. The findings evidence that spontaneous NBT-test values are regularly growing in all three cell types, and the stimulation coefficients lowers as the process grows in severity at the expense of pulmonary tissue disintegration and bronchial obstruction; these parameters adequately reflect the status of the body specific reactivity. Significant correlations were revealed between spontaneous NBT-test parameters in all 3 cell types and their stimulation coefficients. This permits a conclusion that spontaneous and induced NBT-test of the peripheral blood cells may help assess alveolar macrophage function.

Some bioenergetic patterns were studied in blood and blood plasma of patients with pulmonary tuberculosis as well as--in rats after long-term daily administration of rifampycin and isoniazid at therapeutic doses. A series of bioenergetic patterns, estimated simultaneously, enabled to detect the side reactions caused by chemotherapy before occurrence of clinical symptoms. Correlation was analysed between these patterns and the routine biochemical tests used for evaluation of the drug side effects. A scheme describing relationship between amino acid transamination in blood plasma and reactions of energy metabolism is presented. The scheme shows the sequence of activation of various enzymatic reactions in blood plasma after an increase in consumption of tissue energy resources in various tissues.

Long-term administration of therapeutic doses of rifampicin and isoniazid or their combination induces an activation of NAD-dependent enzymes in the plasma and red cells of experimental rats. The ATP/ADP ratio decrease in all the experimental groups, while the degree of pyridine nucleotide reduction rises due to a combined action of the drugs. This effect is similar to the state of hypoxia.