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The phase-field model of Wheeler, Boettinger and McFadden is extended to the case of fast solidification in which local non-equilibrium phenomena occur in the bulk phases and within the diffuse solid – liquid interface. Such an extension leads to the characteristic diffusion speeds of atoms (both within the diffuse interface and inside the bulk phases) and to the speed of the interface propagation. As a result, the model is described by a system of hyperbolic equations for the atomic diffusion transport as well as for the phase-field. This model is applied to the problem of solute trapping, which is accompanied by the entrapment of solute atoms beyond chemical equilibrium by a rapidly moving interface. The model predicts the beginning of complete solute trapping and diffusionless solidification at a finite solidification velocity.

Clinical study of the efficiency of Poetam (affinity-purified antibodies to recombinant human erythropoietin) in the treatment of anemia in patients with pubertal uterine hemorrhages proved that combined therapy with Poetam and iron preparation normalized erythron parameters, structural and metabolic status of erythrocytes, and ferrokinetic parameters of the peripheral blood sooner than monotherapy with Poetam or sorbifer.

Abstract We studied the role of β-adrenergic mechanisms of regulation of erythropoiesis in the formation of the erythron system reaction during severe hypoxia. Blockade of β-adrenoceptors after the incidence of hypoxic encephalopathy of different genesis was followed by an increase in the number of committed precursors in the bone marrow, hyperplasia of the erythroid hemopoietic stem, and rise in the count of peripheral blood erythrocytes. These changes were accompanied by decreased formation of abnormal erythrocytes.

Abstract We studied changes in the erythroid hemopoietic stem during blood loss of different severity. Stimulation of erythropoiesis during the posthemorrhagic period was related to functional activation of erythroid precursors, which resulted from changes in feeder capacity of cells from the hemopoiesis-inducing microenvironment and erythropoietic activity of the plasma. The development of encephalopathy under conditions of massive blood loss was accompanied by a reduction of erythroid hyperplasia due to a decrease in the number of proliferating erythroid precursor cells, despite high secretory activity of adherent myelokaryocytes, rise in erythropoietic activity of the plasma, increased formation of erythroid hemopoietic islets, and accelerated maturation of hemopoietic cells.

We studied changes in the erythroid hemopoietic stem during phenylhydrazine-induced hemolytic anemia. Stimulation of erythropoiesis was associated with increased functional activity of erythroid precursors, which resulted from changes in feeder capacity of hemopoiesis-inducing microenvironmental cells and erythropoietic activity of the plasma. The development of encephalopathy induced by a hemolytic poison was accompanied by a decrease in hyperplasia of bone marrow erythropoiesis. It was related to a decrease in the number of proliferating erythroid precursor cells. These changes accompanied the increase in the secretory function of adherent myelokaryocytes, rise in erythropoietic activity of the plasma, enhanced formation of erythroid hemopoietic islets, and accelerated maturation of hemopoietic cells.

Abstract: We studied changes in the erythroid hemopoietic stem during phenylhydrazine-induced hemolytic anemia. Stimulation of erythropoiesis was associated with increased functional activity of erythroid precursors, which resulted from changes in feeder capacity of hemopoiesis-inducing microenvironmental cells and erythropoietic activity of the plasma. The development of encephalopathy induced by a hemolytic poison was accompanied by a decrease in hyperplasia of bone marrow erythropoiesis. It was related to a decrease in the number of proliferating erythroid precursor cells. These changes accompanied the increase in the secretory function of adherent myelokaryocytes, rise in erythropoietic activity of the plasma, enhanced formation of erythroid hemopoietic islets, and accelerated maturation of hemopoietic cells.

We studied changes in the erythroid hemopoietic stem during phenylhydrazine-induced hemolytic anemia. Stimulation of erythropoiesis was associated with increased functional activity of erythroid precursors, which resulted from changes in feeder capacity of hemopoiesis-inducing microenvironmental cells and erythropoietic activity of the plasma. The development of encephalopathy induced by a hemolytic poison was accompanied by a decrease in hyperplasia of bone marrow erythropoiesis. It was related to a decrease in the number of proliferating erythroid precursor cells. These changes accompanied the increase in the secretory function of adherent myelokaryocytes, rise in erythropoietic activity of the plasma, enhanced formation of erythroid hemopoietic islets, and accelerated maturation of hemopoietic cells.

The current concept of eukaryotic DNA polymerases is considered, which are involved in nuclear DNA repair. The data are given on a new group of DNA polymerases that maintain the integrity of DNA structures without preliminary excision of damaged regions. A special attention is paid to specific features of the functioning of repair DNA polymerases in embryogenesis of the loach. A possible existence is discussed of the previously unknown pathway of DNA repair with participation of DNA polymerase δ as independent from the nuclear antigen of proliferating cells.

Cytological and histological studies of the thymus, bone marrow, peripheral blood, spleen, and lymph nodes in 6-9-month-old AKR/JY mice showed that the risk of thymic lymphoma in these animals increased with age. Generalization of the tumor process was observed in mice aged over 8 months and first involved the spleen, then the lymph nodes, bone marrow, and liver. A case of primary lymphoma in the spleen was detected.

Carboplatin injected intravenously in a maximum permissible dose to Wistar rats inhibited erythro- and granulocytopoiesis in the bone marrow, caused hyporegenerative anemia, leukopenia, and thrombocytopenia in the peripheral blood, led to hypoplasia of the thymus and spleen, and produced moderate apoptosis-inducing effects. These effects were observed within the first month after treatment. In mice carboplatin induced chromatid aberrations in the bone marrow and increased the count of erythrocytes with micronuclei. Moderate hypoplasia of erythro- and granulocytopoiesis and accelerated involution of the thymus were observed 3 and 6 months after cytostatic treatment. Our results indicate that carboplatin possesses higher myelotoxic activity compared to cisplatin.

We studied structural changes and biosynthetic processes in the gastric epithelium in patients with chronic duodenal ulcer. The severity of alterative ultrastructural changes in surface epithelial and glandular cells progressively increased from proximal to distal portion of the stomach. Biosynthesis of nucleic acids within the epithelium depended on the morphofunctional state of epitheliocytes. DNA biosynthesis in the fundus was less intensive. The intensity of RNA synthesis did not differ between various gastric regions. Our results suggest that structural and metabolic dimorphism of the fundic and pyloric epithelium underlies pathological changes in the mucosa during ulcer disease.

Abstract: The pyrolysis of trichlorosilane in the presence of different amounts of chloroform and the copyrolysis of HSiCl3 with buta-1,3-diene in the presence of 1 mol.% chloroform were studied. The enthalpies of formation of products resulting from the pyrolysis of HSiCl3 in the presence of chloroform were calculated by the quantum chemical method. Based on the thermochemical data as well as data from GLC and mass spectrometry, it was concluded from the condensate composition that introduction of chloroform into the zone of pyrolysis of HSiCl3 favors generation of silylenes.

The results of new isochoric heat capacity measurements of H2O + Na2CO3solutions as a function of temperature along several isochores in the near-critical region of pure water are reported. The measurements cover temperatures from 331 to 661 K at Na2CO3mole fraction 0.008869. The experiments were performed at seven densities between 245 and 875 kg-m−3. The measurements were made in a high-temperature, high-pressure, adiabatic, and nearly constant-volume calorimeter. Uncertainties of the isochoric heat capacity measurements are estimated to be 1–2% in the liquid phase, 2–3% in the vapor phase, and 4–5% near the critical point. Measurements were made in the two-phase (vapor–liquid, liquid–solid, vapor–solid) and three-phase (vapor–liquid–solid) regions. Two peaks in isochoric heat capacity have been found near the critical point of pure water. One of the peaks at TS1occurs on the three-phase (L–V–S) curve and another peak at TS2corresponds to a two-phase (L–S or V–S) curve. The experimental values of phase transition temperatures TS(ρ) on each isochore was determined. Uncertainty in the phase transition temperature measured was no greater than ±0.03 to 0.05 K.

Abstract: Pyrolysis of trichlorosilane (TCS) and copyrolysis of TCS with 1,3-butadiene were studied. The enthalpies and activation energies for the reactions of the products of TCS pyrolysis were found by quantum-chemical calculations. A direct study of the pyrolysis of TCS by mass spectrometry was carried out. Based on the thermochemical parameters found by quantum-chemical calculations and on the results of GLC and mass spectrometry concerning the composition of the pyrolysis products, it was concluded that the pyrolysis of TCS follows a scheme that includes formation of radicals and silylenes.

Abstract: Pyrolysis of hexamethyldisiloxane (HMDS) and its copyrolysis with chlorotrimethylsilane and tetrachlorosilane were studied. Based on the data of GLC analysis and on the mass spectrum of the condensate obtained after the pyrolysis of HMDS, it was concluded that HMDS acts as a source of dimethylsilanone. The results of the copyrolysis of HMDS with chlorotrimethylsilane used as a trapping reagent indicate that the dimethylsilanone generated from HMDS can be inserted into the Si−Cl and Si−O bonds. In the copyrolysis of HMDS with tetrachlorosilane serving as a trapping reagent for dimethylsilanone, both dimethylsilanone and dichlorosilanone are generated.

Unit activity in the medial preoptic and septal regions of the brain was studied in rabbits in response to changes in the local temperature and to systemic injection of leukocytic and bacterial pyrogens. A decrease in the discharge frequency of warmth receptors and activation of cold receptors were found under the influence of the pyrogens. Leukocytic pyrogen induced a faster decrease than bacterial pyrogens in the activity of warmth receptors. Temperature-neutral neurons did not respond significantly to pyrogens of either type.

We studied the effects of ultralow doses of antibodies to erythropoietin on antenatal and postnatal development of rat offspring. Daily administration of the preparation on days 1-6, 6-16, and 16-19 of pregnancy did not increase embryonic mortality and was not associated with congenital malformations, fetal growth retardation, high incidence of pathological changes in fetal organs, and delayed ossification (compared to control and intact animals). For evaluation of their embryotoxic effect manifested in the postnatal period ultralow doses of antibodies to erythropoietin were administered throughout pregnancy. The offspring of treated and intact rats did not differ in physical development, appearance of sensory and locomotor reflexes, locomotor, exploratory, and emotional behavior, and learning and adaptive capacities.

Single injection of quinine in a maximum tolerable dose to BALB/c mice caused morphological changes in the testes and suppressed spermatogenesis. Gonocytes in all layers of the spermatogenic epithelium, interstitial endocrinocytes, and sustenocytes proved to be sensitive to the toxic effect of the drug. The majority of detected morphological changes were reversible.

Single injection of quinine in a maximum tolerable dose to BALB/c mice caused morphological changes in the testes and suppressed spermatogenesis. Gonocytes in all layers of the spermatogenic epithelium, interstitial endocrinocytes, and sustenocytes proved to be sensitive to the toxic effect of the drug. The majority of detected morphological changes were reversible.

Based on main principles of porous silicon (por-Si) formation the research of producing containers for drug delivery systems was launched. Nanoparticles for loading medicine were obtained.

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ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.