Abstract  OBJECTIVE: To determine whether nicardipine, a dihydropyridine, inhibits the ability of calcium gluconate to reverse magnesium-induced toxicity.

METHODS: The reversal of magnesium-induced neuromuscular blockade of skeletal muscle in the presence of nicardipine was assessed using a nerve stimulator. Nicardipine (12 mg) or an equivalent volume of saline was administered intramuscularly to 19 nonpregnant rabbits in a randomized, blinded manner. Magnesium sulfate, 800 mg, was then infused intravenously in all animals, an amount sufficient to cause toxicity as measured by depression of skeletal muscle twitch and by average serum levels of 10.4 mEq/L. Calcium gluconate (300 mg) was then infused in all animals, and reversal of neuromuscular blockade was measured using the nerve stimulator to compare the saline- and nicardipine-treated groups.

RESULTS: Administration of calcium gluconate was equally effective in reversing magnesium-induced toxicity in both the control and test groups.

CONCLUSION: Nicardipine does not block the ability of calcium gluconate to reverse magnesium-induced neuromuscular blockade.

Abstract  In this work, a one-pot strategy for directly converting fructose into 2,5-diformylfuran (DFF) over Mo-containing Keggin heteropolyacids (HPAs) in open air is developed. H3 PMo12 O40 HPA is found to show high activity and selectivity to the formation of DFF owing to its higher Brønsted acidity and moderate redox potential. The partial substitution of the H(+) in H3 PMo12 O40 with Cs(+) leads to the heterogenization of the HPA by forming its cesium salts Csx H3-x PMo12 (x=0.5, 1.5, and 2.5). A satisfactory yield of 69.3% to DFF is obtained over Cs0.5 H2.5 PMo12 polyoxometalate after deliberate optimization of the reaction conditions. The heterogenized polyoxometalate could be recycled and reused without significant loss of catalytic activity for five runs. The produced DFF could be separated from the resulting mixture by an adsorption-desorption method using activated carbon as the adsorbent and furfural as the desorbent. A highest isolated yield of 58.2% is obtained.

Abstract  Enzymatic fuel cells have received considerable attention because of their potential for direct conversion of abundant raw materials such as cellulose to electricity. The use of multi-enzyme cascades is particularly attractive as they offer the possibility of achieving a series of complex reactions at higher efficiencies. Here we reported the use of a DNA-guided approach to assemble a five-component enzyme cascade for direct conversion of cellulose to gluconic acid and H2O2. Site-specific co-localization of β-glucosidase and glucose oxidase resulted in over 11-fold improvement in H2O2production from cellobiose, highlighting the benefit of substrate channeling. Although a more modest 1.5-fold improvement in H2O2production was observed using a five-enzyme cascade, due to H2O2inhibition on enzyme activity, these results demonstrated the possibility to enhance the production of gluconic acid and H2O2directly from cellulose by DNA-guided enzyme assembly.

Abstract  The two electrophilic Vilsmeier-Haack reagents POCl3.DMF 2 or (CF3SO2)2O.DMF 3 mediate the one-step and selective conversion of O-triethylsilyl (O-TES), O-tert-butyldimethylsilyl (O-TBDMS), O-tert-butyldiphenylsilyl (O-TBDPS), and O-triisopropylsilyl (O-TIPS) ethers of D-glucal to the corresponding C(6)-O-formates.

Abstract  Despite the increasing clinical use of topical platelet-rich plasma (PRP) to enhance tissue healing and regeneration, there is no properly standardized method of autologous PRP gel preparation. This study examined the effect of the centrifugation time and gravitational force (g) on the platelet recovery ratio of PRP and determined the most effective centrifugation conditions for preparing PRP. Two-step centrifugations for preparing PRP were used in 39 subjects who had consented prior to the study's start. The separating centrifugation (Step 1, used to separate whole blood into its two main components: red blood cells and plasma) was tested from 500g to 1900g at 200g increments for 5 minutes (min), and from 100g to 1300g at 200g increments for 10 minutes. After separating centrifugation, upper plasma layer was transferred to another plain tube for the condensation centrifugation and remaining lower cell layer was discarded. The condensation centrifugation (Step 2, used to condense the platelets in the separated plasma) was tested at 1000g for 15 min, 1500g for 15 min, 2000g for 5 min and 3000g for 5 min, additionally at 1000g for 10 min and 1500g for 10 min. Platelet gelation was induced by adding 10% calcium gluconate to final PRP with volume ratio of 1:10. The optimal separating centrifugation conditions were followed by 900g for 5 minutes and the condensation conditions were followed by 1500g for 15 minutes, of which recovery ratios were 92.0 ± 3.1% and 84.3 ± 10.0%, respectively.

Abstract  Gold (Au) catalysts have been rarely investigated for the oxidation of glucose in the absence of a base. These conditions are critical, however, to enable the sequential one-pot combination of cellulose hydrolysis and glucose oxidation. Here we evaluate the catalytic performance and stability of Au nanoparticles supported on metal oxides for the oxidation of glucose to gluconic acid under unadjusted pH and acidic conditions. The study provides insights into the deactivation of the catalysts caused by leaching and hydrothermal sintering of Au nanoparticles, as well as by adsorption of reactive species. We found that lowering the surface density of Au on metal oxides decreases the sintering rate of the Au nanoparticles and hence enhances the stability and activity of the catalysts.

Abstract  The effects of reverse osmosis (RO) membrane type on the rejection efficiency of boric acid, monoborate and boron complexes with D-mannitol, sodium D-gluconate and N-methyl D-glucamine was revealed. The membranes examined included: XLE, TW-30, BW-30 and SW-30, supplied by DOW (TM) FILMTEC (TM). The mass transport coefficients: permeability and reflection coefficient were determined for each species in boric acid-polyol aqueous system. The influence of the membrane type upon these coefficients was evaluated and quantitative, comparative analysis of the efficacy of boron rejection at varying permeate flux, the feedwater boron content, the alcohol/boron molar ratio and the pH was conducted. It was found that boron rejection in the above systems was determined by the extent of boric acid transport, even when boric acid constituted only a minor component of the feedwater. At high permeate flux the effectiveness in boric acid rejection decreased in the following descending membrane order: SW-30 > BW-30 > TW-30 > XLE. The results presented here enable the selection of the best membrane, the most suitable operating conditions for boron separation by RO in the presence or absence of polyols, and for quantitative prediction of the efficiency of boron removal with various RO membranes. (C) 2013 Elsevier B.V. All rights reserved.

Abstract  Screen-printed carbon electrodes have been modified with tetrathiafulvalene and sulfite oxidase enzyme for the sensitive and selective detection of sulfite. Amperometric experimental conditions were optimized taking into account the importance of quantifying sulfite in wine samples and the inherent complexity of these samples, particularly red wine. The biosensor responds to sulfite giving a cathodic current (at +200 mV vs screen-printed Ag/AgCl electrode and pH 6) in a wide concentration range, with a capability of detection of 6 μM (α=β=0.05) at 60°C. The method has been applied to the determination of sulfite in white and red samples, with averages recoveries of 101.5% to 101.8%, respectively.

Abstract  An emerging approach toward development of injectable, self-setting, and fully biodegradable bone substitutes involves the combination of injectable hydrogel matrices with a dispersed phase consisting of nanosized calcium phosphate particles. Here, novel injectable composites for bone regeneration have been developed based on the combination of ultrapure alginate as the matrix phase, crystalline CaP [monetite and poorly crystalline hydroxyapatite (HA)] powders as both a dispersed mineral phase and a source of calcium for cross-linking alginate, glucono-delta-lactone (GDL) as acidifier and glycerol as both plasticizer and temporary sequestrant. The composites were maximized with respect to CaP content to obtain the highest amount of osteoconductive filler. The viscoelastic and physicochemical properties of the precursor compounds and composites were analyzed using rheometry, elemental analysis (for calcium release and uptake), acidity [by measuring pH in simulated body fluid (SBF)], general biocompatibility (subcutaneous implantation in rabbits), and osteocompatibility (implantation in femoral condyle bone defect of rabbits). The gelation of the resulting composites could be controlled from seconds to tens of minutes by varying the solubility of the CaP phase (HA vs. monetite) or amount of GDL. All composites mineralized extensively in SBF for up to 11 days. In vivo, the composites also disintegrated upon implantation in subcutaneous or bone tissue, leaving behind less degradable but osteoconductive CaP particles. Although the composites need to be optimized with respect to the available amount of calcium for cross-linking of alginate, the beneficial bone response as observed in the in vivo studies render these gels promising for minimally invasive applications as bone-filling material.

Abstract  The synthesis and structure-activity relationship (SAR) of thiophene-C-glucosides have been explored, and the human sodium-dependent glucose cotransporter 2 (hSGLT2) inhibitory activities and rat urinary glucose excretion (UGE) effects of 3a-f were evaluated. As a result, they showed good hSGLT2 inhibitory activities and rat UGE effects. In particular, the chlorothiophene derivative 3f showed remarkable inhibitory activity against hSGLT2.

Abstract  [reaction: see text] Glucal 3-carbamates 1 and 7 underwent oxidative cyclization with iodobenzene diacetate or iodosobenzene in the presence of Rh2(OAc)4, providing mannosamine 2-N,3-O-oxazolidinones. With iodosobenzene, incorporation of 4-penten-1-ol provided a readily separable anomeric mixture of n-pentenyl glycosides, with the anomers exhibiting pronounced differences in reactivity as glycosyl donors. N-acylation of the sugar oxazolidinones led to alpha-selective glycosyl donors for the elaboration of various 2-mannosamine frameworks. Alternatively, the anomeric n-pentenyl glycosides of N-Cbz 2-mannosamine oxazolidinones were converted separately to oxazolidinone-opened derivatives 28alpha and 28beta. These served as stereoconvergent glycosyl donors, and the alpha-linked products were readily advanced to a variety of N-acetylmannosamine (ManNAc) frameworks, using an intramolecular O-->N acetyl transfer as the final step.

Abstract  A multifunctional mediating system for bioelectrocatalytic oxidation of glucose is described. It comprises a conducting polymer, poly(3,4-ethylenodioxythiophene), carbon nanotubes modified with 4-(pyrrole-1-yl) benzoic acid that provide carboxyl groups that aid immobilization of glucose oxidase in a conductive three-dimensional network, tetrathiafulvalene that mediates electron exchange with the enzyme. This composite produces a system that is capable of effective oxidation of glucose to gluconic acid at pH7. The current is concentration dependent to at least 60mM and maintains 77% of initial response for 35 days. Data supporting the utility of this system for electrochemical sensing and biofuel cell technology are presented.

Abstract  All presently used batteries contain reactive, corrosive or toxic components and require strong cases, usually made of steel. As a battery is miniaturized, the required case dominates its size. Hence, the smallest manufactured batteries are about 50 mm3 in size, much larger then the integrated circuits or sensors of functional analytical packages, as exemplified by implantable glucose sensors for diabetes management. The status of the miniaturization of the power sources of such implantable packages is reviewed. Three microcells, consisting only of potentially harmless subcutaneously implantable anodes and cathodes, are considered. Because their electrolyte would be the subcutaneous interstitial fluid, the cells do not have a case. One potentially implantable cell has a miniature Nafion-coated Zn anode and a biocompatible hydrogel-shielded Ag/AgCl cathode. The core innovation on which the cell is based is the growth of a hopeite-phase Zn2+ conducting solid electrolyte film on the discharging anode. The film blocks the transport of O2 to the Zn, preventing its corrosion, while allowing the necessary transport of Zn2+. The second cell, with the same anode, would have a bioinert hydrogel-shielded wired bilirubin oxidase-coated carbon cathode, on which O2 dissolved in the subcutaneous fluid would be electroreduced to water. In the third cell, the glucose of the subcutaneous interstitial would be electrooxidized to gluconolactone at an implanted wired glucose anode, similar to that tested now for continuous glucose monitoring in diabetic people, and O2 in the subcutaneous fluid would be electroreduced to water on its wired bilirubin oxidase cathode.

Abstract  In this paper, the influence of carbon and silica particle slurry concentration up to 20 g/l (4 vol%) on regime transition, gas hold-up, and volumetric mass transfer coefficient is studied in a 2-dimensional slurry bubble column. From high speed video image analysis, the average large bubble diameter, the frequency of occurrence of large bubbles, the gas-liquid interfacial area, and the large bubble hold-up are obtained. The liquid side mass transfer coefficient is calculated from the volumetric mass transfer coefficient and the gas-liquid interfacial area. The lyophilic silica particles are rendered lyophobic by a methylation process to study the influence of particle wettability. The influence of organic electrolyte (sodium gluconate) and the combination of electrolyte and particles is also studied. It is found that lyophilic silica, lyophobic silica, and lyophobic carbon particles at concentrations larger than 2 g/l (0.4 vol%) decrease the gas hold-up and shift the regime transition point (where the first large bubbles appear) to a lower gas velocity. The volumetric mass transfer coefficient increases with gas velocity, increases with electrolyte concentration, decreases with slurry concentration, and is higher for lyophobic particles. The liquid side mass transfer coefficient increases with gas velocity, bubble diameter, and is higher for lyophobic particles. A correlation for the mass transfer coefficient based on dimensionless numbers is proposed for the heterogeneous regime.

Abstract  We originally identified senescence marker protein 30 (SMP30) as a distinctive protein whose expression decreases in an androgen-independent manner with aging. Here, we report its sequence homology found in two kinds of bacterial gluconolactonases (GNLs) by using the blast search. Then, through a biochemical study, we identify SMP30 as the lactone-hydrolyzing enzyme GNL of animal species. SMP30 purified from the rat liver had lactonase activity toward various aldonolactones, such as d- and l-glucono-delta-lactone, d- and l-gulono-gamma-lactone, and d- and l-galactono-gamma-lactone, with a requirement for Zn(2+) or Mn(2+) as a cofactor. Furthermore, in SMP30 knockout mice, no GNL activity was detectable in the liver. Thus, we conclude that SMP30 is a unique GNL in the liver. The lactonase reaction with l-gulono-gamma-lactone is the penultimate step in l-ascorbic acid (AA) biosynthesis, and the essential role of SMP30 in this synthetic process was verified here by a nutritional study using SMP30 knockout mice. These knockout mice (n = 6), fed a vitamin C-deficient diet, did not thrive; i.e., they displayed symptoms of scurvy such as bone fracture and rachitic rosary and then died by 135 days after the start of receiving the deficient diet. The AA levels in their livers and kidneys at the time of death were <1.6% of those in WT control mice. In addition, by using the SMP30 knockout mouse, we demonstrate that the alternative pathway of AA synthesis involving d-glucurono-gamma-lactone operates in vivo, although its flux is fairly small.

Abstract  Kinetic investigation of oxidation of glucose and fructose, by alkaline solution of N-chloronicotinamide (NCN) has been carried out in the temperature range 308-328 K. The reaction shows first order in [alkali] and [substrate] and zero order in oxidant. Addition of nicotinamide (NA) has no effect. Increase in ionic strength of the medium does not change the rate. Effect of temperature on the rate of oxidation has been followed to show the validity of the Arrhenius equation and various activation parameters have been computed. The stoichiometry of the reaction was found to be 1:1. 1,2-enediol is found to be the reactive intermediate. Gluconic acid and formic acid are the products of oxidation for glucose and fructose, respectively.

Abstract  Allylamides of gluconic acid were synthesized by the reaction of allylamine with lactones using dimethyl formamide as a solvent. In this reaction, hydroxyl groups were protected by trimethylsilyl groups via three different pathways that connect sugar units onto the polysiloxane chains. A series of well-defined polysiloxanes with pendent sugar units were prepared by hydrosilation of the trimethylsilyl-protected allylamides with hydric polysiloxanes in the presence of the Platinum dioxide as a catalyst. The catalytic activity and selectivity were discussed in detail. All products were characterized by FT-IR, H-1 NMR, and C-13 NMR spectroscopy, respectively. Furthermore, the shapes of molecular aggregates of target polymers in water were studied by transmission electron microscopy, which reveals that the transitions of micelles-morphologies from spheres to vesicles can be controlled by adjusting hydrogen content of primary materials or by changing initial solvents. (c) 2006 Elsevier Ltd. All rights reserved.

Abstract  Nano- and micro-sized LiFePO4 powders were synthesized by a sodium gluconate (C6H11NaO7)-assisted hydrothermal synthesis method at 220 degrees C for 10 h with pH = 2-7. The resulting powders were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), and energy-dispersive X-ray spectrometer (EDS). The obtained data showed that the pH of synthesis solution played a key role in the formation of the LiFePO4 powders with different morphologies, such as ball-like microspheres, irregular microspheres with the agglomerated rods and particles, sphere-like nanoparticles and nano-ellipsoids. The results from electrochemical performance measurements revealed that the charge-discharge cycling characteristics of the samples were strongly dependent on their morphologies. In particular, the ellipsoidal LiFePO4 nanoparticles with the average size of 70-90 nm showed the highest initial discharge capacity of 150 mA h g(-1) at 0.1 C rate, and cycling stability of the ellipsoidal LiFePO4 nanoparticles was optimum among all the samples prepared due to their dual advantages of high tap density and good diffusion property. The present study offers a simple morphology-controllable route, without carbon coating or doping with supervalent cations, to synthesize and to design high performance cathode materials for lithium-ion batteries. (C) 2013 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.

Abstract  The real-time dynamic heterogeneity of the gelation process of the amino acid derivative Fmoc-tyrosine (Fmoc-Y) is studied using particle tracking microrheology. To trigger gelation, glucono-δ-lactone (GdL) is added, which gradually lowers the p H over several hours. The onset of self-assembly in the system is signified by a sharp drop in the mean-squared displacement of embedded particles, a phenomenon that is found to correlate with the p H of the system reaching the pK(a) of Fmoc-Y. The gel point is identified and found to be dependent on the GdL concentration. Analysis of embedded probe particle dynamics allows the heterogeneity of the sample to be quantified, using three metrics: the heterogeneity ratio (HR), the non-Gaussian parameter of the van Hove correlation function (N and the bin distribution of the mean-squared displacement (MSD) of single particles (f(z)). Results from the three techniques are found to be approximately comparable, with increases in heterogeneity observed in all samples for incubation times t(w) = 0-3 hours. The final heterogeneity in all samples is found to be remarkably low compared to other systems previously reported in the literature.

Abstract  Tetranuclear copper(II) complexes containing alpha-D-glucose-1-phosphate (alpha-D-Glc-1P), [Cu4(mu-OH){mu-(alpha-D-Glc-1P)}2(bpy)4(H2O)2]X3 [X = NO3 (1a), Cl (1b), Br (1c)], and [Cu4(mu-OH){mu-(alpha-D-Glc-1P)}2(phen)4(H2O)2](NO3)3 (2) were prepared by reacting the copper(II) salt with Na2[alpha-D-Glc-1P] in the presence of diimine ancillary ligands, and the structure of 2 was characterized by X-ray crystallography to comprise four {Cu(phen)}2+ fragments connected by the two sugar phosphate dianions in 1,3-O,O' and 1,1-O mu4-bridging fashion as well as a mu-hydroxo anion. The crystal structure of 2 involves two chemically independent complex cations in which the C2 enantiomeric structure for the trapezoidal tetracopper(II) framework is switched according to the orientation of the alpha-D-glucopyranosyl moieties. Temperature-dependent magnetic susceptibility data of 1a indicated that antiferromagnetic spin coupling is operative between the two metal ions joined by the hydroxo bridge (J = -52 cm(-1)) while antiferromagnetic interaction through the Cu-O-Cu sugar phosphate bridges is weak (J = -13 cm(-1)). Complex 1a readily reacted with carboxylic acids to afford the tetranuclear copper(II) complexes, [Cu4{mu-(alpha-D-Glc-1P)}2(mu-CA)2(bpy)4](NO3)2 [CA = CH3COO (3), o-C6H4(COO)(COOH) (4)]. Reactions with m-phenylenediacetic acid [m-C6H4(CH2COOH)2] also gave the discrete tetracopper(II) cationic complex [Cu4{mu-(alpha-D-Glc-1P)}2(mu-m-C6H4(CH2COO)(CH2COOH))2(bpy)4](NO3)2 (5a) as well as the cluster polymer formulated as {[Cu4{mu-(alpha-D-Glc-1P)}2(mu-m-C6H4(CH2COO)2)(bpy)4](NO3)2}n (5b). The tetracopper structure of 1a is converted into a symmetrical rectangular core in complexes 3, 4, and 5b, where the hydroxo bridge is dissociated and, instead, two carboxylate anions bridge another pair of Cu(II) ions in a 1,1-O monodentate fashion. The similar reactions were applied to incorporate sugar acids onto the tetranuclear copper(II) centers. Reactions of 1a with delta-D-gluconolactone, D-glucuronic acid, or D-glucaric acid in dimethylformamide resulted in the formation of discrete tetracopper complexes with sugar acids, [Cu4{mu-(alpha-D-Glc-1P)}2(mu-SA)2(bpy)4](NO3)2 [SA = D-gluconate (6), D-glucuronate (7), D-glucarateH (8a)]. The structures of 6 and 7 were determined by X-ray crystallography to be almost identical with that of 3 with additional chelating coordination of the C-2 hydroxyl group of D-gluconate moieties (6) or the C-5 cyclic O atom of D-glucuronate units (7). Those with D-glucaric acid and D-lactobionic acid afforded chiral one-dimensional polymers, {[Cu4{mu-(alpha-D-Glc-1P)}2(mu-D-glucarate)(bpy)4](NO3)2}n (8b) and {[Cu4{mu-(alpha-D-Glc-1P)}2(mu-D-lactobionate)(bpy)4(H2O)2](NO3)3}n (9), respectively, in which the D-Glc-1P-bridged tetracopper(II) units are connected by sugar acid moieties through the C-1 and C-6 carboxylate O atoms in 8b and the C-1 carboxylate and C-6 alkoxy O atoms of the gluconate chain in 9. When complex 7 containing d-glucuronate moieties was heated in water, the mononuclear copper(II) complex with 2-dihydroxy malonate, [Cu(mu-O2CC(OH)2CO2)(bpy)] (10), and the dicopper(II) complex with oxalate, [Cu2(mu-C2O4)(bpy)2(H2O)2](NO3)2 (11), were obtained as a result of oxidative degradation of the carbohydrates through C-C bond cleavage reactions.

Abstract  Applicability of a skin test induced by dinitrofluorobenzene [DNFB] to quantification of the actual level of cellular immunity [CI] in vivo and its level after an experimental immunomodulation intervention were evaluated in two breeds [40 animals in each] of fattening bulls [10-11 months old]. At the selected methodical procedure of intensity determination of the delayed type of hypersensitivity [DTH], its average value reached 4.5 + 1.5 mm in 80 animals, while in 77.5 % of bulls its level ranged from 3.6 to 9.6 mm. in 18.7 % from 2.0 to 3.5 mm and in 3.8 % remained less than 2.0 mm Evident expression of the reaction points to the possibility of application of the used methodical procedure of the skin test using DNFB to quantify the level of CI response in vivo in cattle. Percentual representation of animals according to the intensity of skin reaction [Tab. I] and concentration of total serum immunoglobulins [CS-Ig] and serum IgG [Tab. II] indicates the different cellular and humoral state of animals in investigated breeds. This is also confirmed by the recorded average values of mentioned parameters which were significantly lower [P < 0.01; or 0.05] In animals of the first breed [4.0 +/- 1.3 mm; 28.3 +/- 4.4 U ZST, 18.4 +/- 3.5 g . l-1] than in breed 2 [4.9 +/- 1.6 mm: 32.5 +/- 3.8 U ZST; 20.3 +/- 3.5 g . l-1]. The animals of each breed were divided into four experimental groups with the approximately equal actual levels of DTH [Tab. III]. Immunomodulation effects of a single administration of soluble fungal glucal [Pleurotus ostreatus] at the dose 5 mg [RFG 5 group] and 10 mg . kg-1 [RFG 10 group] and levamisol [Nilverm inj.] at the dose 5 mg . kg-1 [L 5 group] on CI response tested on day 30 after application were compared to the control. While animals of breed 1 demonstrated positive glucal effects. for both doses used on DTH reaction to DNFB, both in comparison to its level before application [P < 0.5] and to the level of control animals after its application [P < 0.05; or 0.01], [Tab. III]. similar effects of glucan were recorded in the bulls of breed 2 no. Potentiating effects of levamisol [5 mg . kg-1] on DTH to DNFB were observed in none of the breeds.

Abstract  beta-1,4-Galactosyltransferase has been investigated with regard to its acceptor specificity and used in the synthesis of galactosides with 5-thioglucose, glucal, deoxynojirimycin, modified N-acetylglucosamine, and glucose derivatives as acceptors. The galactoside products are potentially useful as endoglycosidase or glycosyltransferase inhibitors or as intermediates for the synthesis of complex oligosaccharides. The conformation of each enzyme product has been investigated with NMR; all are shown to possess similar glycosidic torsional angles based on a significant NOE between H-1 of Gal and H-4 of the acceptor. Comparison of the transferase reactions with the beta-1,4-galactosidase-catalyzed galactosyl transfer reactions indicates that the transferase reactions provide exclusively a beta-1,4-glycosidic linkage while the galactosidase reactions predominantly form a beta-1,6-glycosidic linkage.

Abstract  A pregnant, miniature horse mare had clinical signs of hepatoencephalopathy and concurrent hypocalcemia. The signs included dullness, inappetence, blindness, head pressing, weakness, muscle fasiculations, uveitis, and urinary incontinence. Hepatic dysfunction and hypocalcemia were confirmed by serum biochemical analysis. The mare was treated successfully with a continuous infusion of Ringer solution, calcium gluconate, dextrose, B-complex vitamins, sodium ampicillin, and flunixin meglumine; topical administration of ophthalmic ointments; and decompression of the urinary bladder. Histologic examination of a liver biopsy specimen revealed acute hepatic necrosis, which likely was associated with administration of a vaccine of equine origin 2 months earlier.

Abstract  The catalyst of highly dispersed gold nanoparticle supported on active carbon was prepared by sodium citrate reduction-colloid gold immobilization method, and its catalytic activity was evaluated by the liquid phase catalytic oxidation reaction of glucose to gluconic acid. The research results show that the sodium citrate amounts have important influence on the size of gold particles in gold colloidal preparation and the catalytic activity of Au/C catalyst obtained. The decrease of the activity for repeatedly used Au/C catalyst may be attributed to the decrease of the Au delta+-O delta- binding state on the catalyst surface. At the same time the catalytic activity for the liquid phase oxidation of glucose was compared between the prepared Au/C catalyst and the commercial Pd/C catalyst, and the results indicated that the Au/C catalyst was advantageous over Pd/C catalyst.

Abstract  The efficient control of fermentation processes requires reliable monitoring systems. This paper describes a fully automated monitoring system based on the on-line combination of ultrafiltration and column liquid chromatography. An evaluation of the performance of a hollow-fibre ultrafiltration module is provided and a method for the determination of sugars, alcohols and organic acids during a gluconic acid and a beer fermentation is presented. The system can be used for at least 250 h with complex fermentation broths under both aerobic and anaerobic conditions without any detrimental effect on either the fermentation or the chromatographic part. Depending on the application 3-5 analyses can be performed every hour, using only 3.0 mul of sample per analysis. Using refractometric or direct UV detection the linear dynamic range is from 0.2 to 150 g l-1 for most of the compounds, while with a simple post-column derivatization procedure sugars can be determined in the low mg l-1 range.