[reaction: see text] A simple, selective, rapid, and efficient procedure for the synthesis of secondary amines from the reductive alkylation of either aliphatic or aromatic nitro compounds and the corresponding amines is reported. Ammonium formate is used as the hydrogen source and Pd/C as the hydrogen transfer catalyst. The reaction is carried out at room temperature. The rate differences for the preferential formation of secondary over tertiary products are due to both steric and electronic factors.

The right Asphaltene Inhibitor (AI) selection is crucial for the control of asphaltene issues in oil production. Although many factors contribute for the asphaltene precipitation/deposition in the fields, the chemical selection process in the laboratory were often conducted only under ambient temperature and pressure. In this paper, we introduced a multifaceted approach for asphaltene inhibitor selection process to overcome the test condition discrepancy between laboratory and the fields. The importance of temperature on the performance of chemicals was evidenced by our high temperature optical scanning device results. The Coupon Deposition Test (CDT) clearly demonstrated the difference between deposition and precipitation behavior and the impact of the water phase on inhibitor performance. High pressure Asphaltene Rocking Cell (ARC) enabled to incorporate high pressure, high temperature and water conditions in the laboratory to show the difference of inhibitor performances. By incorporating field conditions such as temperature, brine composition and pressure into our tests, better recommendations can be achieved that would have not been possible with any optical, precipitation based technique. Furthermore, a suite of AI test methods which cover various field conditions brings a degree of refinement in product selection unmatched by any single method and allows for selection of the best asphaltene chemical program for a particular field through its life cycle.

Asphaltene deposition in capillaries is a tool that has been used in an attempt to better understand asphaltene deposition in the field. However, data reproducibility and inhibitor ranking present some challenges with this technique. An improved asphaltene capillary deposition unit and a novel experimental protocol were developed to address these problems and are presented here. Using untreated Gulf of Mexico oil, the current study generated reproducible amounts of asphaltene deposit inside the capillary. It further identified the fact that residual oil inside the capillary tube can be a limitation to inhibitor selection. Evaluating the amount of asphaltene depositing in the capillary as a function of time proved successful in addressing this issue and led to inhibitor performance differentiation.

The CyDye family of fluorescent dyes is currently the overwhelming choice for applications in proteomic analysis, using two-dimensional difference gel electrophoresis (2D-DIGE). Protein labeling with CyDyes is hampered by protein precipitation and gel smearing when used above minimal labeling. The solubility of labeled protein may be improved by introducing water solubilizing groups on the dye such as cysteic acids. However, addition of a negatively charged functionality will have the undesired effect of shifting the pI in relation to the unlabeled protein. These limitations have been addressed through the synthesis of highly water-soluble and pI balancing zwitterionic CyDye fluorophores (Z-CyDyes). The new dyes feature a cysteic acid motif, a titratable amine functionality and a NHS activated ester group. In side by side 2D-DIGE comparisons of Z-CyDyes and CyDyes, the new dyes significantly enhanced protein spot volume and the number of spots that were detected. Z-CyDyes have the potential to enhance the depth of proteome coverage and provide a general strategy for improving the performance of protein tagging reagents.

Securinine, a GABAA receptor antagonist, has been reported to enhance monocyte cell killing of Coxiella burnetii without obvious adverse effects in vivo. We employed multiplex 2D gel electrophoresis using Zdyes, a new generation of covalently linked fluorescent differential protein detection dyes to analyze changes in the monocyte proteome in response to Securinine. Securinine antagonism of GABAA receptors triggers the activation of p38. We used the differential protein expression results to guide a search of the literature and network analysis software to construct a systems biology model of the effect of Securinine on monocytes. The model suggests that various metabolic modulators (fatty acid binding protein 5, inosine 5′-monophosphate dehydrogenase, and thioredoxin) are at least partially reshaping the metabolic landscape within the monocytes. The actin bundling protein L-plastin, and the Ca2+ binding protein S100A4 also appear to have important roles in the immune response stimulated by Securinine. Fatty acid binding protein 5 (FABP5) may be involved in effecting lipid raft composition, inflammation, and hormonal regulation of monocytes, and the model suggests that FABP5 may be a central regulator of metabolism in activated monocytes. The model also suggests that the heat shock proteins have a significant impact on the monocyte immune response. The model provides a framework to guide future investigations into the mechanisms of Securinine action and with elaboration may help guide development of new types of immune adjuvants.

The electrochemical and electrocatalytic properties of two synthetic imidazole analogues of the redox cofactor pyrroloquinoline quinone (PQQ) were evaluated. Cyclic voltammetry measurements as a function of pH indicated that both 4,5-dihydro-4,5-dioxo-1H-imidazolo[5,4-f]quinoline-7,9-dicarboxylic acid (1) and 4,5-dihydro-4,5-dioxo-2-methyl-1H-imidazolo[5,4-f]quinoline-7,9-dicarboxylic acid (2) undergo a reversible reduction of the o-quinone moiety below pH 8 with potentials slightly more positive than those observed for PQQ. Upon incorporation into a polypyrrole membrane on the tip of a glassy carbon electrode, 1 and 2 exhibited electrocatalytic properties sufficient for the indirect amperometric detection of cysteine. The response for cysteine was linear up to 1 mM over a wide pH range. Detection limits (S/N ¼ 3) were in the mM range and dependent on the solution pH. Interference from redox active species such as dopamine and uric acid were minimized by the pH-dependent redox potentials of 1 and 2 and thus the ability to tune the detection potential.

Parallel syntheses of 2-hydro-, 2-methyl-, and 2-methoxycarbonylimidazo-7,9-dimethoxycarbonyl analogues of the oxidation-reduction cofactor pyrroloquinoline quinone [4,5-dihydro-4,5-dioxo-1H-pyrrolo[2,3-f]quinoline-2,7,9-tricarboxylic acid] have been developed. The properties of the imidazolo analogues in relation to the corresponding pyrrole analogues will be important in assessing the origins of catalysis and biological activity in the cofactor, which has recently been shown to be a vitamin.

Coxiella burnetii is an obligate intracellular bacterial pathogen and the causative agent of Q fever. Chronic Q fever can produce debilitating fatigue and C. burnetii is considered a significant bioterror threat. C. burnetii occupies the monocyte phagolysosome and although prior work has explained features of the host-pathogen interaction, many aspects are still poorly understood. We have conducted a proteomic investigation of human Monomac I cells infected with the Nine Mile Phase II strain of C. burnetii and used the results as a framework for a systems biology model of the host response. Our principal methodology was multiplex differential 2D gel electrophoresis using ZDyes, a new generation of covalently linked fluorescent protein detection dyes under development at Montana State University. The 2D gel analysis facilitated the detection of changes in posttranslational modifications on intact proteins in response to infection. The systems model created from our data a framework for the design of experiments to seek a deeper understanding of the host-pathogen interactions.