Comparison of Culture and a Novel 5' Taq Nuclease Assay for Direct Detection of Campylobacter fetus subsp. venerealis in Clinical Specimens from Cattle

A Campylobacter fetus subsp. venerealis-specific 5' Taq nuclease PCR assay using a 3' minor groove binder-DNA probe (TaqMan MGB) was developed based on a subspecies-specific fragment of unknown identity (S. Hum, K. Quinn, J. Brunner, and S. L. On, Aust. Vet. J. 75:827-831, 1997). The assay specifically detected four C. fetus subsp. venerealis strains with no observed cross-reaction with C. fetus subsp. fetus-related Campylobacter species or other bovine venereal microflora. The 5' Taq nuclease assay detected approximately one single cell compared to 100 and 10 cells in the conventional PCR assay and 2,500 and 25,000 cells from selective culture from inoculated smegma and mucus, respectively. The respective detection limits following the enrichments from smegma and mucus were 5,000 and 50 cells/inoculum for the conventional PCR compared to 500 and 50 cells/inoculum for the 5' Taq nuclease assay. Field sampling confirmed the sensitivity and the specificity of the 5' Taq nuclease assay by detecting an additional 40 bulls that were not detected by culture. Urine-inoculated samples demonstrated comparable detection of C. fetus subsp. venerealis by both culture and the 5' Taq nuclease assay; however, urine was found to be less effective than smegma for bull sampling. Three infected bulls were tested repetitively to compare sampling tools, and the bull rasper proved to be the most suitable, as evidenced by the improved ease of specimen collection and the consistent detection of higher levels of C. fetus subsp. venerealis. The 5' Taq nuclease assay demonstrates a statistically significant association with culture (2 = 29.8; P < 0.001) and significant improvements for the detection of C. fetus subsp. venerealis-infected animals from crude clinical extracts following prolonged transport.

Isolation and characterization of a methionine adduct of DOPA o-quinone

The o-quinone of DOPA, an important intermediate implicated in many biological processes, has been found to react with methionine. The product has been isolated and studied, and tentative structure has been assigned.

Isolation, characterization and mapping of temperature-sensitive mutants of mycobacteriophage I3

Eighteen temperature-sensitive mutants of mycobacteriophage I3 have been isolated and partially characterized. All the mutants were defective in vegetative replication. Based on temperature shift experiments with the temperature sensitive mutants, the thermosensitive phase of the phage development period has been characterized for each mutant. The genes have been mapped by recombination analysis. The early, continuous and middle genes seem to cluster on the genetic map

Synthesis, characterization and photocatalytic activity of MxCe1-xVO4 (M = Li, Ca and Fe)

Non-stoichiometric substituted cerium vanadates, MxCe1-xVO4 (M = Li, Ca and Fe), were synthesized by solid-state reactions. The crystal structure was analyzed by powder X-ray diffraction and it exhibits a tetragonal zircon Structure, crystallizing in the space group I4(1)/amd with a = 7.3733(4) and c = 6.4909(4) angstrom and Z = 4. Particle sizes were in the range of 600-800 nm, as observed by scanning electron microscopy. The thermal analysis of the compounds showed phase stability up to 1100 degrees C. The UV diffuse reflectance spectra indicated that the compounds have band gaps in the range of 2.6-2.9 eV. The photocatalytic activity of these Compounds was investigated for the first time for the degradation of different dyes, and organics, the oxidation of cyclohexane and the hydroxylation of benzene. The degradation of dyes was modeled using the Langmuir-Hinshelwood kinetics, while the oxidation of cyclohexane and hydroxylation of benzene were modeled using a free radical mechanism and a series reaction mechanism, respectively.

Structural and functional characterization of dendritic arbors and GABAergic synaptic inputs on interneurons and principal cells in the rat basolateral amygdala

The basolateral amygdala (BLA) is a complex brain region associated with processing emotional states, such as fear, anxiety, and stress. Some aspects of these emotional states are driven by the network activity of synaptic connections, derived from both local circuitry and projections to the BLA from other regions. Although the synaptic physiology and general morphological characteristics are known for many individual cell types within the BLA, the combination of morphological, electrophysiological, and distribution of neurochemical GABAergic synapses in a three-dimensional neuronal arbor has not been reported for single neurons from this region. The aim of this study was to assess differences in morphological characteristics of BLA principal cells and interneurons, quantify the distribution of GABAergic neurochemical synapses within the entire neuronal arbor of each cell type, and determine whether GABAergic synaptic density correlates with electrophysiological recordings of inhibitory postsynaptic currents. We show that BLA principal neurons form complex dendritic arborizations, with proximal dendrites having fewer spines but higher densities of neurochemical GABAergic synapses compared with distal dendrites. Furthermore, we found that BLA interneurons exhibited reduced dendritic arbor lengths and spine densities but had significantly higher densities of putative GABAergic synapses compared with principal cells, which was correlated with an increased frequency of spontaneous inhibitory postsynaptic currents. The quantification of GABAergic connectivity, in combination with morphological and electrophysiological measurements of the BLA cell types, is the first step toward a greater understanding of how fear and stress lead to changes in morphology, local connectivity, and/or synaptic reorganization of the BLA.

Microsomal 11-Alpha-hydroxylation of progesterone in Aspergillius ochraceus: Part I: Characterization of the hydroxylase system

Microsomes (105,000xg sediment) prepared from induced cells of A.ochraceus was found to hydroxylate progesterone to 11-Alpha-hydroxyprogesterone (11a-OHP) in high yields (85-�90% in 30 min.) in the presence of NADPH and O2. The pH optimum for the hydroxylase was found to be 7.7. However, for the isolation of active microsomes grinding of the mycelium should be carried out at pH 8.3. Metyrapone, carbon monoxide, SKF-525A, p-CMB and N-methyl maleimide inhibited the hydroxylase activity indicating the involvement of cytochrome P-450 system. The inhibition of the hydroxylase by cytochrome Image and the presence of high levels of NADPH-cytochrome Image reductase in induced microsomes suggest that the reductase could be one of the components in the hydroxylase system.

An elegant direct route for the preparation of pyridinium, ammonium and alkali metal hexafluorotitanates (IV)

Pyridinium hexafluorotitanate (IV) has been prepared by a one step procedure. Addition of titanium tetrachloride to pyridinium poly(hydrogen fluoride) yields nearly quantitative amounts of pyridinium hexafluorotitanate(IV). Making use of pyridinium hexafluorotitanate as precursor, ammonium and alkali metal (Na, K, Rb, and Cs) hexafluorotitanates have been prepared in good yields. These salts have been characterised by IR, N.M.R. (1H, 13C and 19F), X-ray powder diffraction data and chemical analysis.

Pyridinium poly(hydrogen fluoride). A versatile fluorinating reagent preparation and characterization of nonmetal and metal complex fluoro salts

Abstract is not available.

Purification and Characterization of a New Indole Oxygenase from the Leaves of Tecoma stans L.

A new indole oxygenase from the leaves of Tecoma stans was isolated and purified to homogenity. The purified enzyme system catalyzes the conversion of indole to anthranilic acid. It is optimally active at pH 5.2 and 30°C. Two moles of oxygen are consumed and one mole of anthranilic acid is formed for every mole of indole oxidized. Dialysis resulted in complete loss of the activity. The inactive enzyme could be reactivated by the addition of concentrated dialysate. The enzyme is not inhibited by copperspecific chelators, non-heme iron chelators or atebrin. It is not a cuproflavoprotein, unlike the other indole oxygenases and oxidases.

Formulation and characterization of drug-loaded microparticles using distillers dried grain kafirin

Kafirin, a protein extracted from sorghum grain, has been formulated into microparticles and proposed for use as a delivery system owing to the resistance of kafirin to upper gastrointestinal digestion. However, extracting kafirin from sorghum distillers dried grains with solubles (DDGS) may be more efficient, because the carbohydrate component has been removed by fermentation. This study investigated the properties and use of kafirin extracted from DDGS to formulate microparticles. Prednisolone, an anti-inflammatory drug that could benefit from a delayed and targeted delivery system to the colon, was loaded into DDGS kafirin microparticles by phase separation with sodium chloride. Scanning electron micrographs revealed that the empty and prednisolone-loaded microparticles were round in shape and varied in size. Surface binding studies indicated prednisolone was loaded within the microparticles rather than being solely bound on the surface. These findings demonstrate DDGS kafirin can be formulated into microparticles and loaded with medication. Future studies could investigate the potential applications of DDGS kafirin microparticles as an orally administered targeted drug-delivery system.

Direct electrochemical formation of nanostructured amorphous Co(OH)2 on gold electrodes with enhanced activity for the oxygen evolution reaction.

The oxides of cobalt have recently been shown to be highly effective electrocatalysts for the oxygen evolution reaction (OER) under alkaline conditions. In general species such as Co3O4 and CoOOH have been investigated that often require an elevated temperature step during their synthesis to create crystalline materials. In this work we investigate the rapid and direct electrochemical formation of amorphous nanostructured Co(OH)2 on gold electrodes under room temperture conditions which is a highly active precursor for the OER. During the OER some conversion to crystalline Co3O4 occurs at the surface, but the bulk of the material remains amorphous. It is found that the underlying gold electrode is crucial to the materials enhanced performance and provides higher current density than can be achieved using carbon, palladium or copper support electrodes. This catalyst exhibits excellent activity with a current density of 10 mA cm-2 at an overpotential of 360 mV with a high turnover frequency of 2.1 s-1 in 1 M NaOH. A Tafel slope of 56 mV dec-1 at low overpotentials and a slope of 122 mV dec-1 at high overpotentials is consistent with the dual barrier model for the electrocatalytic evolution of oxygen. Significantly, the catalyst maintains excellent activity for up to 24 hr of continuous operation and this approach offers a facile way to create a highly effective and stable material.

The Alpha-Method Direct Transcription In Path Constrained Dynamic Optimization

Numerically discretized dynamic optimization problems having active inequality and equality path constraints that along with the dynamics induce locally high index differential algebraic equations often cause the optimizer to fail in convergence or to produce degraded control solutions. In many applications, regularization of the numerically discretized problem in direct transcription schemes by perturbing the high index path constraints helps the optimizer to converge to usefulm control solutions. For complex engineering problems with many constraints it is often difficult to find effective nondegenerat perturbations that produce useful solutions in some neighborhood of the correct solution. In this paper we describe a numerical discretization that regularizes the numerically consistent discretized dynamics and does not perturb the path constraints. For all values of the regularization parameter the discretization remains numerically consistent with the dynamics and the path constraints specified in the, original problem. The regularization is quanti. able in terms of time step size in the mesh and the regularization parameter. For full regularized systems the scheme converges linearly in time step size.The method is illustrated with examples.

Direct estimation of an element of order matrix from H-1 NMR spectra of strongly dipolar coupled spins

NMR spectra of molecules oriented in thermotropic liquid crystalline media provide information on the molecular structure and order. The spins are generally strongly dipolar coupled and the spectral analyse require the tedious and time consuming numerical iterative calculations. The present study demonstrates the application of multiple quantum spin state selective detection of single quantum transitions for mimicking the homonuclear decoupling and the direct estimation of an element of ordering matrix. This information is utilized to estimate the nearly accurate starting dipolar couplings for iterative calculations. The studies on the spectra of strongly dipolar coupled five and six interacting spin systems are reported.

Synthesis and Characterization of Carbon-Coated LiNi1/3Co1/3Mn1/3O2 in a Single Step by an Inverse Microemulsion Route

Layered LiNi1/3Co1/3Mn1/3O2, which is isostructural to LiCoO2, is considered as a potential cathode material. A layer of carbon coated on the particles improves the electrode performance, Which is attributed to an increase of the grain connectivity and also to protection of metal oxide from chemical reaction. The present work involves in situ synthesis of carbon-coated submicrometer-sized particles of LiNi1/3Co1/3Mn1/3O2 in an inverse microemulsion medium in the presence of glucose. The precursor obtained from the reaction is heated in air at 900 degrees C for 6 h to get crystalline LiNi1/3Co1/3Mn1/3O2. The carbon coating is found to impart porosity as well as higher surface area in relation to bare samples of the compound. The electrochemical characterization studies provide that carbon-coated LiNi1/3Co1/3Mn1/3O2 samples exhibit improved rate capability and cycling performance. The carbon coatings are shown to suppress the capacity fade, which is normally observed for the bare compound. Impedance spectroscopy data provide additional evidence for the beneficial effect of a carbon coating on LiNi1/3Co1/3Mn1/3O2 particles.