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Objectives: Intraoperative tumor visualization with 5-aminolevulinic acid (5-ALA) induced protoporphyrin IX (PpIX) fluorescence is widely applied for improved resection of high-grade gliomas. However, visible fluorescence is present only in a minority of low-grade gliomas (LGGs) according to current literature. Nowadays, antiepileptic drugs (AEDs) are frequently administered to LGG patients prior to surgery. A recent in-vitro study demonstrated that AEDs result in significant reduction of PpIX synthesis in glioma cells. The aim of this study was thus to investigate the role of 5-ALA fluorescence in LGG surgery and the influence of AEDs on visible fluorescence. Patients and Methods: Patients with resection of a newly diagnosed suspected LGG after 5-ALA (25 mg/kg) administration were initially included. During surgery, the presence of visible fluorescence (none, mild, moderate, or bright) within the tumor and intratumoral fluorescence homogeneity (diffuse or focal) were analyzed. Tissue samples from fluorescing and/or non-fluorescing areas within the tumor and/or the assumed tumor border were collected for histopathological analysis (WHO tumor diagnosis, cell density, and proliferation rate). Only patients with diagnosis of LGG after surgery remained in the final study cohort. In each patient, the potential preoperative intake of AEDs was investigated. Results: Altogether, 27 patients with a histopathologically confirmed LGG (14 diffuse astrocytomas, 6 oligodendrogliomas, 4 pilocytic astrocytomas, 2 gemistocytic astrocytomas, and one desmoplastic infantile ganglioglioma) were finally included. Visible fluorescence was detected in 14 (52%) of 27. In terms of fluorescence homogeneity (n = 14), 7 tumors showed diffuse fluorescence, while in 7 gliomas focal fluorescence was noted. Cell density (p = 0.03) and proliferation rate (p = 0.04) was significantly higher in fluorescence-positive than in fluorescence-negative samples. Furthermore, 15 (56%) of 27 patients were taking AEDs before surgery. Of these, 11 patients (73%) showed no visible fluorescence. In contrast, 10 (83%) of 12 patients without prior AEDs intake showed visible fluorescence. Thus, visible fluorescence was significantly more common in patients without AEDs compared to patients with preoperative AED intake (OR = 0,15 (CI 95% 0.012-1.07), p = 0.046). Conclusions: Our study shows a markedly higher rate of visible fluorescence in a series of LGGs compared to current literature. According to our preliminary data, preoperative intake of AEDs seems to reduce the presence of visible fluorescence in such tumors and should thus be taken into account in the clinical setting.

A course of dihydroquercetin (antioxidant) injections to 5-month-old Wistar rats with sulpiride-induced benign prostatic hyperplasia led to reduction of proliferative activity in the glandular structures and to attenuation of the inflammatory reaction in the tissue. Prostatic antioxidant/prooxidant balance returned to normal after the treatment.

2,6-Di-tert-butyl-p-quinone 1′-phthalazynylhydrazone (HL) is synthesized; the total energies and geometry of the possible hydrazone tautomeric forms are calculated by quantum chemical methods. The hydrazone phthalazone tautomer is shown to be the most stable, which is well consistent with the 1H NMR spectroscopic data for hydrazone. An X-ray crystallographic analysis is performed of the hydrazone-based Zn(II) trinuclear complex, in which zinc atoms are linked by the diazine bridge of the phthalazine cycle and two pivalate bridges. The geometric properties of the monodeprotonated hydrazone residue in the complex are similar to the calculated data for the phthalazone hydrazone tautomeric form.

Experiments on Wistar rats showed that cisplatin and carboplatin induced similar morphological alterations in the ovaries. Both agents reduced the number of structural and functional elements, but the effect of cisplatin was more pronounced. Morphological changes observed in the early period after injection of the preparations were accompanied by prolongation of the estrous cycle, which was longer in rats treated with carboplatin. Partial and reversible sterility was observed in females at the early terms after cisplatin treatment.

The possibility of boosting antifibrotic activity of testicular hyaluronidase immobilized on polyethylene oxide with spiperone was studied on the bleomycin models of a single (partially reversible pneumofibrosis) and repeated (irreversible pneumofi brosis) injuries to the alveolar epithelium in C57Bl/6 mice. The antifibrotic effect was more pronounced after successive treatment with immobilized hyaluronidase and spiperone than after individual treatment with each of the compounds: no collagen deposition in the parenchyma of bleomycin-damaged lungs was found. The decrease in inflammatory cell (lymphocytes, macrophages, neutrophils, plasma cells) infi ltration of the alveoli and alveolar tracts interstitium in mice treated by immobilized hyaluronidase and spiperone did not differ from the anti-inflammatory effect of spiperone monotherapy.

Productivity of spermatogenesis and the population of spermatogonial cells were substantially reduced in male Wistar rats 3 months after administration of cytostatic drug paclitaxel, damaging stem spermatogonia. However, signs of reparative regeneration appeared in the testicular tissue. In animals receiving paclitaxel in combination with granulocyte CSF, the same period of observation, the number of spermatogonia and the effi ciency of spermatogenesis at the same terms of the study did not differ from those in intact animals. Intensive recovery processes started 1 month earlier than after administration of paclitaxel alone. These data attest to pronounced potentiating effect of granulocyte CSF on reparative regeneration of the testicular tissue.

Bottom sediments from the central zone of the Sea of Okhotsk were preliminarily dated. The petromagnetic parameters of two groups of samples formed at cold and warm climatic stages were studied. Warm oxygen isotopic stages and substages were characterized by the coexistence of pseudo-single-domain allogenic magnetite and predominant magnetite and greigite (pyrrhotite) grains subject to biologic control. At cold stages, sediments containing a mixture of pseudo-single-domain and multidomain terrigenous magnetite particles accumulated. The petromagnetic curves agree with the normalized standard oxygen isotopic curve over the last 350 kyr of the column section.

The paper examines the effect of the wetting time on the contact angle θ of WC and Ti wetting by Ni 3 A melt. It is shown that the equilibrium θ value varies between 38 and 0°. It is established that the miscibility of WC in Ni 3 Al intermetallic compound is 3 to 4% at T = 1500°C. A differential thermal analysis has revealed that the liquid phase in the WC–Ni 3 Al system shows up 20 to 25°C lower than the melting point of pure Ni 3 Al. A microstructural analysis has shown that WC–Ni 3 Al alloys contain two phases: WC-based phase and solid solution of WC in Ni 3 Al. The work of adhesion is calculated; it shows that chemical interaction prevails. The microstructure of the contact area is analyzed.

The effect of the holing time on the wetting angle (θ) of tungsten and titanium carbides by the melt of the Ni3Al intermetallic compound is investigated. It is shown that the equilibrium value of θ varies from 38 to 0 deg. It is established that the solubility of WC in the Ni3Al intermetallic compound equals 3–4% at t = 1500°C. The temperature of the appearance of the liquid phase in the WC-Ni3Al system is determined by differential thermal analysis. This temperature turned out to be 20–25°C lower than for pure Ni3Al. It is revealed that the WC-Ni3Al alloys consist of two phases. The first phase is based on WC, and the second phase is based on the solid solution of tungsten carbide in Ni3Al. The values of the adhesion work, which indicate that the chemical interaction is prevalent in this system, are calculated. The microstructure of the contact region is evaluated.

A microwave digestion procedure with the use of specially designed autoclaves and a domestic microwave oven is proposed for the mass-spectrometric determination of the elemental composition of bottom sediments. The throughput of sample preparation in routine analysis was considerably increased because of the elimination of a purification step. Reaction mixture compositions and microwave digestion conditions were chosen to reach complete decomposition (within the limits of error of semiquantitative ICP MS analysis) of Baikal bottom sediments with respect to the majority of elements. It was found that the procedure is unsuitable for the determination of Sn, Zr, Nb, Hf, As, and Sb. The approximate concentrations of elements in a BIL-1 certified reference material of Baikal bottom sediments were found: Tl, 0.52 ± 0.16 ppm; Bi, 0.33 ± 0.10 ppm; I, 14.3 ± 4.3 ppm; Cd, 0.31 ± 0.09 ppm; and Pb, 0.24 ± 0.07 ppm.

Intraperitoneal injection of paclitaxel (Mitotax) in a single dose of 40 mg/kg was followed by an increase in the number of mitotic granulocytic and erythroid cells, hypoplasia, and pancytopenia of the bone marrow in CBA/CaLac mice. The test preparation decreased the number of hematopoietic precursor cells for erythropoiesis and granulocytopoiesis, but increased the count of polyploid cells and incidence of structural and genomic abnormalities in bone marrow cells. These changes were reversible.

A simple, reliable, and high-performance method has been proposed for direct determination of the isotopic composition of authigenic uranium in silica lacustrine sediments. The method is based on studying the kinetics of the selective extraction of authigenic uranium from sediments with weak solutions of ammonium hydrocarbonate followed by the ICP-MS analysis of the nuclides. To estimate the contamination of authigenic uranium by terrigenous one, the contents of 232Th and some other clastogenic elements in the extracts were measured simultaneously. The selectivity of extraction of authigenic uranium from the sediments treated with a 1% NH4HCO3 solution appeared to be no worse than 99%. The method was used to analyze the isotopic composition of authigenic uranium at several key horizons of a core dated before. The measurements directly prove that the 234U/238U values in Baikal water varied depending on climate, which contradicts the previous statements. The measured 234U/238U ratios in paleo-Baikal water match the values reconstructed from isotopic data for total uranium in the sediments on the supposition that the U/Th ratio is constant in the terrigenous part of the sediment. Direct experimental determination of total and authigenic nuclides in sediments enhances the potentiality of the method for absolute 234U-230Th dating of carbonate-barren lacustrine sediments, including those from Lake Baikal, within the intervals corresponding to the periods of glaciation, where the sediments contain a large fraction of terrigenous component. Given the fractions of terrigenous and authigenic uranium are accurately determined, we have an opportunity to study the variability of the sources of terrigenous matter and to refine the previous model for reconstructing the climate humidity in East Siberia.

We studied processes of proliferation and differentiation of hemopoietic precursor cells in mice treated with granulocyte CSF under conditions of cytostatic myelodepression. It was found that the hemostimulating effect of original granulocyte CSF preparation consists in accelerated maturation of hemopoietic precursors and increased content of DNA-synthesizing CFU-GM in the bone marrow.

Modern status of pharmacopoeian HPLC analysis and its main shortcomings are discussed. The philosophy "special analytical method for each substance" has to be revised, and as an alternative, a principle of creation of universal methods realized by means of HPLC analyzers is proposed. A prototype of such analyzer is described. The device was designed on the basis of a Milichrome A-02 gradient chromatograph with spectrophotometric detector and reverse phase column.

The content of hemopoietic precursors in the bone marrow, its morphological composition, production of hemopoietic growth factors by cells of the hemopoietic microenvironment, erythropoietic activity, and plasma content of endogenous erythropoietin were studied in CBA/CaLac mice with hypoplasia of hemopoiesis induced by adriamycin in a maximum permissible dose. Cytostatic treatment affected production of substances determining erythropoietic activity by adherent and nonadherent cells of the bone marrow. Erythropoietic activity of peripheral blood plasma considerably increased. Recovery of erythroid hemopoiesis was determined by the effects of endogenous erythropoietin and other substances secreted by cells of the hemopoietic microenvironment and present in the peripheral blood.

We studied the reactions of granulocytic hemopoietic stem after acute hypoxia and during the development of posthypoxic encephalopathy. Damage to brain structures was associated with intensification of the bone marrow hemopoiesis due to activation of hemopoiesis-inducing microenvironment and more intense formation of hemopoietic islets, despite reduced proliferative capacity of granulocytic precursors.

Experiments on the emergence of a counterflow in gas-generating cells with high continuous electrodes and a small electrode–membrane gap, in which the bubble layer abruptly extends over the entire cross-section of the cell, may be explained in terms of a “two-speed” model of interacting jets of the bubble layer and the free liquid developed earlier. The viscous-flow model provides only a qualitative description of the phenomenon. The difference in the magnitude of the electrode screening with gas and the gas content near the surface as parameters of macroscopic models of electrolyzers is stressed. The role played by the electrolyte oversaturation with gas in the bubble layer formation dynamics is analyzed. The relative coefficient of hydraulic loss in the initial part of the flow is estimated.

We studied structural and functional organization of the bone marrow, production of hemopoietic growth factors by hemopoietic cells, and plasma colony-stimulating and erythropoietic activities in CBA/CaLac mice treated with etoposide. The effects of etoposide on cultured hemopoietic and microenvironmental cells were also evaluated. Our results indicate that hemopoietic growth factors secreted by adherent bone marrow cells play the major role in the normalization of hemopoiesis during etoposide-induced myelosuppression.

The mechanistim of carbon black (CB) effects on the thermo-oxidative degradation of linear low density polyethylene (LLDPE) was studied. Quantitative measurement, in both the kinetic and diffusion mode, of the kinetics of LLDPE's thermo-oxidative degradation was done in four ways as follows: (i) in the absence of both CB and a stabilizer; (ii) in the absence of a stabilizer but in the presence of CB (Black Pearl 3700) (2), (iii) without CB but in the presence of an amine stabilizer (AI) (iv) with both CB and AI. The stabilizer chosen for this study was polymerized 1,2-dihydro-2,2,4-trimethylquinoline (Trademark: Naugard Super Q). Measurements were done at 180° C, the AI concentration being (1.1–9.8)×10−2 mol/kg, based upon a molecular mass of 0.874 kg/mol for the monomer unit. CB concentration was 5% by weight while oxygen pressure pO2=(50–300) mm Hg. Quantitative parameters for the thermo-oxidative degradation of LLDPE were established for kinetic and diffusion conditions. The kinetics of the inhibited thermo-oxidative degradation of LLDPE, in the presence of an amine antioxidant such as Naugard Super Q, was found to be essentially no different than the degradation kinetics in the presence of hindered phenolic antioxidants. It was shown that CB may act as an inhibitor albeit a rather weak one. However, during inhibition of the thermo-oxidative degradation of LLDPE with AI, CB shows itself to be an effective synergist, especially over the AI concentration range of from (2 to 6) × 10−2 mol/kg (0.4–1.2% by weight). The most probable explanation for this synergy lies in the adsorption of stabilizer radical In onto the surface of the CB particles and a resultant decrease in the value of the rate constant k10 of the chain transfer reaction between a polymer molecule RH and Inhibitor radical In .

Pharmacological blockade of dopamine- and serotoninergic structures with haloperidol and cyproheptadine, respectively, attenuated hyperplasia of bone marrow granulocytopoiesis and erythropoiesis (cyproheptadine) caused by conflict situation. At the same time, haloperidol and, especially, cyproheptadine normalized suppressed erythropoiesis and modulated activated granulocytopoiesis under conditions of paradoxical sleep deprivation. These results indicate that central regulation of hemopoietic stems is mediated by different neurotransmitter mechanisms. Erythropoiesis depends on the state of serotoninergic structures, while granulocytopoiesis is regulated both by the dopamine- and serotoninergic systems.

Immune reactions of the progeny of female Wistar rats injected with paclitaxel a single MPD of 1 and 3 months before mating with intact males were studied. Thymic hyperplasia was detected in the progeny of female rats mated 1 month after treatment. Disorders in the antibody-specific and antibody-nonspecific mechanisms of the immune response were detected in the progeny of females mated with intact males 3 months after cytostatic treatment.

In patients with lung cancer and malignant tumors of the head and neck, erythrocyte hyperpolarization associated with the opening of Ca2+-activated potassium channels develops with lower rate and amplitude compared with that in healthy donors. Restoration of normal membrane potential is Ca2+-ATPase-dependent. The rate of restoration is significantly higher in patients with tumors. Two groups with different hyperpolarization response and their dynamics during chemotherapy were identified in patients with lung cancer. Ca2+-induced erythrocyte hyperpolarization and its dynamics during cytostatic therapy depend on tumor localization and histological type.

Intravenous injection of antitumor drug vepeside in the maximum tolerated dose (MTD) stimulated free radical oxidation processes in rats. Activities of blood aminotransferases and alkaline phosphatase changed. Morphological study of the liver revealed fatty degeneration, hepatocyte necrosis, and inflammatory infiltration.

Antitumor drug paclitaxel administered in MTD to female rats 1, 3, and 6 months before mating with intact males had a toxic effect on the progeny. We observed increased anteand postnatal mortality, decelerated physical development, low rate of formation of sensorimotor reflexes, impaired learning capacity, and disturbed adaptation behavior. Antenatal mortality considerably increased in the progeny of rats receiving the drug 3 months before mating. The maximum number of pathological changes in viable progeny was found in rats treated with the cytostatic 6 months before mating.

The morphology and function of the ovaries at the early and late terms after single intravenous injection of paclitaxel in the maximum tolerated dose (MTD) were studied in female Wistar rats. Evaluation of the structural and functional elements of the female gonads showed that the targets for the drug were primordial, bi-and multilayer follicles. The number of graafian follicles and corpora lutea did not decrease. A more pronounced (copared to the control) depletion of the ovarian reserve potentialities was detected during the remote period. The drug did not decrease mating capacity and efficiency. On the other hand, high fetal mortality was observed in females treated with paclitaxel, which decreased with lengthening of the period between the cytostatic treatment and mating.

The involvement of PI3K, ERK and p38-dependent signaling system in the regulation of functional activity of erythroid precursors after blood loss (30% of circulating volume) was studied. We demonstrated the important role of PI3K and p38 in the suppression of differentiation of erythroid precursors the contribution of p38 to stimulation of mitotic activity of erythroid CFU, which maintains the growth potential of the precursors at the optimal physiological level. The classical MAPK/ERK-kinase pathway does not determine the proliferative and differentiation status of erythroid CFU.

Quantitative and qualitative composition of hemopoietic tissue and the intensity of proliferation and differentiation of committed hemopoietic precursors are studied in mice treated with adriamycin, cyclophosphane, or 5-fluorouracil. It is shown that intense maturation of colony-forming units results in rapid regeneration of hemopoiesis even under conditions of reduced proliferation of these cells, whereas inhibition of their differentiation suppresses restoration of bone marrow cellularity despite intense proliferation of hemopoietic precursors.

Pronounced regenerative effects of alkaloid napelline extracted from Aconitum baicalense on granulocytic hemopoiesis were revealed in the model of cytostatic myelosuppression. Activation of functions of hemopoietic progenitor cells along with increased feeder capacity of the stromal elements in the hemopoiesis inducing microenvironment with decreased levels mesenchymal progenitor cells in the bone marrow are the mechanisms underlying the hemostimulating action of this substance.

Investigations and numerical representation of chemical transformation mechanisms occurring during polymer processing have recently become a very important problem. In this paper a model put forward to describe the interrelation of mechanical degradation and thermal oxidation phenomena during PE extrusion. This model permits determination of changes in molecular weight, the amounts of reacted oxygen and the quantities of accumulated peroxide together with the amount of the inhibitor used during extrusion. These parameters have a significant affect on the physical and mechanical properties of the polymer and make it possible to assess its lifetime in finished products under operating conditions.

Studies of mechanical and thermooxidative degradation and stabilization of polymers were widely developed in late fifties-early sixties. As a result, the main features of these rather complicated processes became more or less clear. Monographs and summing up the results of investigations in this field, have appeared lately.

Chemical transformations occurring during melt processing of polymers such as polyethylene are described in terms of kinetics of relevant reactions. A model is developed which takes into consideration; chemical, thermal, and mechanical effects, autocatalitic reactions, as well as the role of inhibitors. The calculated predictions are verified with the experimental data. The results are used to make recommendations for the improvements of the melt extrusion process.

We studied the effects of lipopolysaccharide, interferon-γ, interleukin-1, or tumor necrosis factor-α and combination treatment with tumor necrosis factor-α and interleukin-1 or interferon-γ on the expression of sialoadhesin receptors on the membrane of bone marrow macrophages, macrophage adherent ability, and production of nitric oxide by these cells. Sialoadhesin expression was evaluated by binding of macrophages to sheep erythrocytes labeled with radioactive 51Cr. Treatment of bone marrow cells with interferon-γ improved adhesive properties of macrophages, but did not modulate expression of sialoadhesin. Interleukin-1 and tumor necrosis factor-α had no effect on the test parameters. Combination treatment with these cytokines enhanced binding of sheep erythrocytes to macrophages. Administration of lipopolysaccharide or combination treatment with interferon-γ and tumor necrosis factor-α increased the count of macrophages adhering to plastic and stimulated expression of sialoadhesin. Combination treatment with interferon-γ and tumor necrosis factor-α stimulated production of nitric oxide by bone marrow macrophages. Blockade of nitric oxide synthesis had no effect on adhesive properties of macrophages and expression of sialoadhesin.

Hemopoiesis-stimulating activity of immobilized oligonucleotide preparation was studied on the model of cytostatic myelosuppression induced by injection of cyclophosphamide and 5-fluorouracil. Immobilized oligonucleotides stimulated regeneration of erythro- and granulocytopoiesis in the bone marrow under conditions of cytostatic treatment. The counts of neutrophilic granulocytes and platelets in the peripheral blood increased. The stimulatory effect of the drug was more manifest in animals with active behavior. The mechanism of immobilized oligonucleotide effect was based on stimulation of functional activity of erythroid and granulocytic macrophage precursors.

Population of spermatogonia was reduced in 2, 3, and 6 months after single intravenous injection of antitumor drug paclitaxel in maximum tolerated dose (MTD). The count of Sertoli cell increased in 3 months after the start of the experiment. The maturity of the seminiferous tubule epithelium was lower than in intact rats. Spermatogenesis productivity did not differ from that in intact animals 6 months after start of the experiment. These data indicate that regeneration of the spermatogenous tissue after paclitaxel treatment is realized via renewal of the spermatogenic epithelium, but considering the amount of spermatogonial cell population, the recovery rate would be low.

Reactions of methyl and ethyl hetaryl ketones in the CCl4/solid KOH system in the presence of 18 crown-6 at room temperature yield the corresponding 2-hetaryl-2-trichloromethyloxiranes in 8–22% yields. Reactions of sterically hindered ketones of the type (hetaryl)COCHR2 (R = Me, Et) with CCl4/OH- form the corresponding a-hydroxy ketones of the type (hetaryl)COC(OH)R2 in 28–44% yields.

The kinetics of thermal and thermo-oxidative degradation of polystyrene (PS) alone and in the presence of 4,4′-isopropylidene bis (2,6-dibromophenol) were investigated. It was shown that the retardant affects the thermo-oxidative degradation of PS. Thermal volatilisation analysis (TVA), subambient TVA, FT-IR spectroscopy and GC-MS techniques were used for the separation and characterisation of the various degradation products. The main products of thermo-oxidative degradation were styrene, carbon dioxide, water, benzaldehyde, α-methylstyrene, phenol, phenylacetaldehyde and acetophenone.

Alkylation of 2 furanyl- and 2-thienylalkyl ketoximes with alkyl, allyl, and propargyl halides in the two phase catalytic system sol. K2CO3/C6H6/18-crown-6 at room temperature causes the formation of mixtures of E- and Z-isomers of the corresponding O-ethers with yields of 32–74%. Partial E/Z-isomerization takes place during the reaction.

Alkyl(2-furyl), alkyl(2-thienyl), and methyl pyridyl ketones form stoichiometric inclusion complexes with β-cyclodextrins. Reduction of these complexes in aqueous solution of Na2CO3 at room temperature yields the corresponding secondary alcohols with an optical yield which attains 27%.

The sonochemical Grignard cross-coupling of 3-bromothiophene with chlorotrimethylsilane in THF affords (3-thienyl) trimethylsilane in 75% yield.

Reactions of 3-acetylthiophene with C1-C4-alkyl iodides in a two-phase benzene/solid KOH system in the presence of l8-crown-6 afford di-C-alkylated derivatives-(3-thienyl)COCHR2 in satisfactory yields (∼50%) with high regioselectivity (70–100%).

C 14 H 13 Cl 2 N 5 cristallise dans P2 1 /c avec a=11,057, b=13,802, c=9,168 A, β=91,07 O , Z=4; affinement jusqu'a R=0,039. Le systeme purine est plan avec une liaison courte C ar -N exocyclique de 1,331 A. L'empilement est caracterise par des interctions d'empilement entre l'heterocycle et l'atome Cl

The vapour-phase oxidation of 2-methylfuran (silvan) in air over vanadium-molybdenum oxide catalysts under specific conditions was unexpectedly found to afford 5-methylenefuran-2(5H)-one (protoanemonin) which is otherwise difficult to obtain.

A novel method for N-alkylation of azyridine-2-oarboxylic acid derivatives with benzyl chloride under phase-transfer conditions or using KF/Al2 O3 as a base was developed. The latter variant of this method was applied to carry out the key step of the alternative synthesis of the dipeptide (S,S)-Bz-Azy-Val-OMe.