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The study was performed for miscanthus introduced and grown in West Siberia. Transformation of miscanthus into bacterial nanocellulose was accomplished for the first time. The microbiological synthesis of bacterial nanocellulose using the Medusomyces gisevii Sa-12 symbiotic culture gave chemically pure bacterial nanocellulose with exceptionally high crystallinity index and content of Iα allomorph. [ABSTRACT FROM AUTHOR]

The effect of culture conditions on the bacterial cellulose (BC) yield synthesized by symbiotic culture Medusomyces gisevii Sa-12 grown in synthetic nutrient medium was studied for the first time. The conditions providing the maximum yield of bacterial cellulose were evaluated: the initial glucose concentration in the culture medium was 20-25 g/L, the temperature was 24-27°C, the ratio of the nutrient medium to the air volume was 1 : 10, and the content of the black tea extracts comprised 1.6-4.8 g/L. A sample of chemically pure BC with the following characteristics was obtained under the selected culture conditions: moisture--99.0%, degree of polymerization--4800, average width of microfibrillar ribbons--30.6 nm, degree of crystallinity--86%, and the content of triclinic modification Ia--98%. [ABSTRACT FROM AUTHOR]

Samples of ash prepared from oat husks and products of their chemical and enzymatic processing in the bacterial nanocellulose production cycle were studied. Their elemental composition and content of the main substance, silicon dioxide, were determined, and the IR spectra and X-ray diffraction patterns were taken. The purest silica was prepared from the dry residue after enzymatic hydrolysis of the product of nitric acid treatment of oat husks, which allows comprehensive use of organic and inorganic components of the vegetable raw material. [ABSTRACT FROM AUTHOR]

The concept of manufacturing valuable bacterial nanocellulose (BNC) from plant raw materials having a zero prime cost is substantiated. The process flowsheet involves the chemical transformation of the feedstock to obtain a pulp; enzymatic hydrolysis of the pulp to furnish a solution of reducing sugars, chiefly glucose; preparation of a nutrient broth based on the enzymatic hydrolysate; biosynthesis of nanocellulose microfibrils by the symbiotic Medusomyces gisevii Sa-12 culture; and purification of BNC. BNC has for the first time been synthesized from oat hulls and has a high degree of crystallinity of 88 ± 5% and is composed of 99% Iα-allomorph. [ABSTRACT FROM AUTHOR]

2,4-dichlorophenoxyacetic acid (2,4-D) and 4-chloro-2-methylphenoxyacetic acid (MCPA) are active substances in many weed-killer agents commonly used for the protection of crops. The literature data accompanied by our former studies showed that in weak-acid and neutral environments these compounds react with bivalent metal ions and form complexes of limited solubility in water. It was assumed that the formation of the complexes can also occur between metals present in soil and herbicides used for plant spraying, which can reduce the uptake of the metals by the above-ground parts of the plants. Our studies concerned copper, zinc and manganese determination in wheat cultured using the pot method under laboratory conditions. Cultures were treated after sprouting with either 2,4-D or MCPA. The content of copper, manganese and zinc was determined in the wheat straw. In comparison with the content in plants untreated with herbicides, the respective values were lower by ~50% for Mn, 20% for Cu and 13% for Zn. [ABSTRACT FROM AUTHOR]

Purpose: The aim of the study was to evaluate the serum concentration of YKL-40 (human cartilage glycoprotein-39) in the assessment of fibrosis stage in children compared to biopsy and prior to antiviral treatment for chronic hepatitis B. Material and methods: We determined serum level of YKL-40 (METRA, EIA kit, Quidel Corporation, San Diego, USA) after an overnight fast in 63 children (age range 4-17 years, mean 10 years) with biopsy-verified chronic HBeAg-positive hepatitis B. Fibrosis stage and inflammation grade were assessed in a blinded fashion according to Ishak et al. We defined advanced liver fibrosis as a score >2. Receiver operating characteristics (ROC) analysis was used to calculate the power of the assay to detect advanced liver fibrosis (AccuROC, Canada). Results: Serum concentration of YKL-40 was significantly higher in patients with chronic hepatitis B compared to controls (n=16) (38.5±19.2 vs 27.9±8.75 ng/mL; p=0.032). The ability of serum YKL-40 to differentiate children with advanced liver fibrosis (n=31; 49.2%) from those with mild fibrosis was not significant (AUC=0.387±0.072, p=0.12). This marker was not a good predictor of histologic inflammation either. Conclusion: Serum level of YKL-40 does not predict advanced liver fibrosis in children with chronic hepatitis B. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate if measurements of MMP-2, MMP-9, TIMP-1 and TIMP-2 have clinical applicability as markers of liver fibrosis and to assess the effect of long-term lamivudine treatment on liver fibrosis in children with chronic hepatitis B (chB). Material and methods: The observation was carried out on 41 children with biopsy proven chB (HBe/+/, HBVDNA/+/) who were nonresponders to previous IFNα therapy. Lamivudine was administered in the group of 29 children (3 mg/kg/day, maximum 100 mg/daily). The serum concentration of examined markers was measured with ELISA before and after 24 months of therapy. ROC analysis was used to calculate the power of the assays to detect advanced liver fibrosis (score >2 according to Batts&Ludwig). Results: Serum TIMP-1 and TIMP-2 levels were significantly higher and MMP-9 lower in children with chB compared to controls. There was a significant positive correlation between serum MMP-2 and negative correlation between MMP-9 level and the stage of liver fibrosis. The ability of serum MMP-9 to differentiate children with mild fibrosis from those with advanced fibrosis was significant (AUC=0.75; p=0.03). Other serum markers did not allow a useful prediction. 2-year lamivudine treatment did not improve histological fibrosis but it caused significant decrease of serum TIMP-2 (p=0.01) and increase of MMP-9 level (p=0.00005). Conclusions: MMP-9 is a better serum fibrosis marker than MMP-2, TIMP-1 and TIMP-2 to diagnose children with advanced liver fibrosis. The significant decrease of TIMP-2 and increase of MMP-9 level during therapy suggest antifibrotic effect of lamivudine in children with chB. [ABSTRACT FROM AUTHOR]

The study verifies the Black Sea wave model using field data obtained from the Katsiveli research platform. The WAM and mesoscale MM5 and WRF atmospheric models, which are used to calculate the wind field for the wave model, were recently adjusted to the Black Sea region at the Marine Hydrophysical Institute. The results of the work are presented as characteristics of the simulation quality used in world practice in other regions. The scatter index for a significant wave height is 70% in summer and 50% in winter. The values of the scatter index of wave parameters and wind speed appear to be at the same level as in semi-enclosed seas on the northern side of the Mediterranean Sea. It is shown that atmospheric simulation correctly reproduces the interaction between synoptic processes and the mountain range extending alongshore. Error sources in wave simulation are discussed. The most significant drawback is the possibility of mesoscale instability in the atmospheric model without assimilation of observation data within the computational domain. [ABSTRACT FROM AUTHOR]

Pulps prepared from oat husks via a method combining prehydrolysis, alkali delignification, and nitric acid treatment were demonstrated to possess high fermentability upon hydrolysis using multienzyme preparations, such as BrewZyme BGX and CelloLux-A. A dependence of the increment of the yield of reducing substances on the initial substrate concentration ranging from 15 to 120 g/dm was studied. The final yield of reducers at 72 h was shown to decline from 88 to 65% with an increase in the initial concentration of the substrate. [ABSTRACT FROM AUTHOR]

Purpose: Obesity, insulin resistance and dyslipidemia are the most significant risk factors of non-alcoholic fatty liver disease (NAFLD) but the role of adipokines in patomechanism of this disease is not clear. The aim of the study was to evaluate the serum levels of leptin, adiponectin and resistin in obese children with NAFLD. Material/Methods: The fasting serum levels of adipokines were determined in 44 consecutive obese children with suspected liver disease and in 24 lean controls. The degree of the ultrasound liver steatosis was graded according to Saverymuttu. Results: The fatty liver was confirmed in 33 children by ultrasonography (16 of them also showed an increased ALT activity). The serum leptin level was significantly higher and adiponectin level was lower in the obese children with NAFLD when compared to controls. Only adiponectin correlated with homeostasis model assessment of insulin resistance (HOMA-IR). Significant negative correlations were found between the ultrasonographic grades of liver steatosis and adiponectin and resistin levels. Serum adiponectin and resistin levels were lower in children with an advanced liver steatosis (grade 3, n=10) compared to patients with a mild steatosis (grade 1-2, n=23). The ability of serum adiponectin and resistin to differentiate children with an advanced liver steatosis from those with mild steatosis was significant. Conclusions: These data suggest a role of both adiponectin and resistin in the pathogenesis of NAFLD in obese children and confirm the association between adiponectin and insulin resistance. Adiponectin and resistin may be suitable serum markers in predicting an advanced liver steatosis in children with NAFLD. [ABSTRACT FROM AUTHOR]

The results of X-ray diffraction analysis of bacterial nanocellulose (BNC), synthesized by Komagataeibacter xylinus В-12429 and Komagataeibacter xylinus В-12431 producers in enzymatic hydrolyzates of miscanthus, oat hull, and synthetic nutrient medium, are presented. It is found by full-profile analysis that the dominant component in all BNC samples studied, independent of the producer and nutrient medium, is allomorph Іα, whose content varies from 96 to 100%. The following characteristics of the supramolecular structure of the samples have been determined: the degree of crystallinity, sizes of elementary fibrils and the shape of their cross section, and the coherence length of elementary fibrils along the fibril axis. [ABSTRACT FROM AUTHOR]

Bacterial nanocellulose, which was produced by Medusomyces gisevii Sa-12 cultured in enzymatic hydrolysates of Miscanthus, was studied by X-ray diffraction. The characteristics of the supramolecular structure of the crystalline component of cellulose samples, such as the degree of crystallinity and the size and shape of elementary fibrils, were determined. The atomic structure was compared with the known structural models of cellulose, and the synthesized bacterial nanocellulose was shown to be cellulose Iα. The lengths and angles of the triclinic unit cell were determined. The composition of the culture medium made from enzymatic hydrolysates of Miscanthus was found to have an effect on the shape and size of elementary fibrils and have no effect on the degree of crystallinity and the fraction of cellulose allomorph Іα. The use of Medusomyces gisevii Sa-12 as the producing organism allows the preparation of bacterial nanocellulose with a high degree of crystallinity in the range of 86–93% containing cellulose allomorph Іα as the major component. [ABSTRACT FROM AUTHOR]

Bacterial nanocellulose, which was produced by Medusomyces gisevii Sa-12 cultured in enzymatic hydrolysates of Miscanthus, was studied by X-ray diffraction. The characteristics of the supramolecular structure of the crystalline component of cellulose samples, such as the degree of crystallinity and the size and shape of elementary fibrils, were determined. The atomic structure was compared with the known structural models of cellulose, and the synthesized bacterial nanocellulose was shown to be cellulose Iα. The lengths and angles of the triclinic unit cell were determined. The composition of the culture medium made from enzymatic hydrolysates of Miscanthus was found to have an effect on the shape and size of elementary fibrils and have no effect on the degree of crystallinity and the fraction of cellulose allomorph Іα. The use of Medusomyces gisevii Sa-12 as the producing organism allows the preparation of bacterial nanocellulose with a high degree of crystallinity in the range of 86–93% containing cellulose allomorph Іα as the major component. [ABSTRACT FROM AUTHOR]

Abstract: Bacterial nanocellulose (BNC) samples were produced by the symbiotic culture Мedusomyces gisevii Sa-12 in synthetic nutrient medium and enzymatic hydrolysates of chemically treated oat hulls and studied by X-ray diffraction. The structural characteristics of the crystalline component of BNC samples were determined. A comparison of the X-ray diffraction patterns recorded in reflection and transmission geometry shows that the samples have an anisotropic structure. All BNC samples are characterized by a high degree of crystallinity (from 86 to 93%) and are mainly composed of the low-symmetry metastable phase Iα (its fraction is 93.6-100%). The Мedusomyces gisevii Sa-12 culture was found to produce highly crystalline BNC, with the low-symmetry phase Iα prevailing, regardless of the composition of the nutrient medium. [ABSTRACT FROM AUTHOR]

Two different methods A and B were used for preparing binuclear furanyl-azine metal complexes encapsulated in NaY zeolite. These new heterogeneous catalysts based on Fe(II) or Cu(II) complexes with a metal/ligand molar ratio of 2:1, were characterized by different spectroscopic techniques and chemical analysis which confirm the presence of the metal complexes inside the supercages of the zeolite. Mössbauer spectroscopy technique analysis confirms the presence of the Fe3+- complexes in octahedral coordination. The new heterogeneous catalysts were catalytic evaluated by phenol hydroxylation and compared with the encapsulated metal furanyl-azine complexes in NaY zeolite. The zeolite themselves do not present any activity and the presence of the metal complexes improve their activity. All heterogeneous catalysts enhance higher conversion of phenol to catechol. Image 1 • Binuclear furanyl-azine metal complexes were successfully encapsulated in NaY zeolite. • Characterization techniques confirm the presence of the metal complexes inside the supercages of the zeolite. • All the heterogeneous catalysts are active in phenol hydroxylation. • The phenol conversion under heterogeneous conditions is close to that obtained for homogeneous counerparts [ABSTRACT FROM AUTHOR]