Meta-Analysis of Mass Balances Examining Chemical Fate during Wastewater Treatment

Mass balances are an instructive means for investigating the fate of chemicals during wastewater treatment. In addition to the aqueous-phase removal efficiency (Φ), they can inform on chemical partitioning, transformation, and persistence, as well as on the chemical loading to streams and soils receiving, respectively, treated effluent and digested sewage sludge (biosolids). Release rates computed on a per-capita basis can serve to extrapolate findings to a larger scale. This review examines over a dozen mass balances conducted for various organic wastewater contaminants, including prescription drugs, estrogens, fragrances, antimicrobials, and surfactants of differing sorption potential (hydrophobicity), here expressed as the 1-octanol−water partition coefficient (KOW) and the organic carbon normalized sorption coefficient (KOC). Major challenges to mass balances are the collection of representative samples and accurate quantification of chemicals in sludge. A meta-analysis of peer-reviewed data identified sorption potential as the principal determinant governing chemical persistence in biosolids. Occurrence data for organic wastewater compounds detected in digested sludge followed a simple nonlinear model that required only KOW or KOC as the input and yielded a correlation coefficient of 0.9 in both instances. The model predicted persistence in biosolids for the majority (>50%) of the input load of organic wastewater compounds featuring a log10KOW value of greater than 5.2 (log10KOC > 4.4). In contrast, hydrophobicity had no or only limited value for estimating, respectively, Φ and the overall persistence of a chemical during conventional wastewater treatment

Immunotherapy with MVA-BN®-HER2 induces HER-2-specific Th1 immunity and alters the intratumoral balance of effector and regulatory T cells

MVA-BN®-HER2 is a new candidate immunotherapy designed for the treatment of HER-2-positive breast cancer. Here, we demonstrate that a single treatment with MVA-BN®-HER2 exerts potent anti-tumor efficacy in a murine model of experimental pulmonary metastasis. This anti-tumor efficacy occurred despite a strong tumor-mediated immunosuppressive environment characterized by a high frequency of regulatory T cells (Treg) in the lungs of tumor-bearing mice. Immunogenicity studies showed that treatment with MVA-BN®-HER2 induced strongly Th1-dominated HER-2-specific antibody and T-cell responses. MVA-BN®-HER2-induced anti-tumor activity was characterized by an increased infiltration of lungs with highly activated, HER-2-specific, CD8+CD11c+ T cells accompanied by a decrease in the frequency of Treg cells in the lung, resulting in a significantly increased ratio of effector T cells to Treg cells. In contrast, administration of HER2 protein formulated in Complete Freund’s Adjuvant (CFA) induced a strongly Th2-biased immune response to HER-2. However, this did not lead to significant infiltration of the tumor-bearing lungs by CD8+ T cells or the decrease in the frequency of Treg cells nor did it result in anti-tumor efficacy. In vivo depletion of CD8+ cells confirmed that CD8 T cells were required for the anti-tumor activity of MVA-BN®-HER2. Furthermore, depletion of CD4+ or CD25+ cells demonstrated that tumor-induced Treg cells promoted tumor growth and that CD4 effector cells also contribute to MVA-BN®-HER2-mediated anti-tumor efficacy. Taken together, our data demonstrate that treatment with MVA-BN®-HER2 controls tumor growth through mechanisms including the induction of Th1-biased HER-2-specific immune responses and the control of tumor-mediated immunosuppression

Asymmetric Organocatalytic Reactions of α,β-Unsaturated Cyclic Ketones

The 1,4-conjugate addition of nucleophiles to \u3b1,\u3b2-unsaturated carbonyl compounds represents one fundamental bond-forming reaction in organic synthesis. The development of effective organocatalysts for the enantioselective conjugate addition of malonate, nitroalkane and other carbon and heteroatom nucleophiles to cycloenones constitutes an important research field and has been explored in recent years. At the same time, asymmetric Diels-Alder reactions have been developed and often a mechanism has been demonstrated to be a double addition rather than synchronous. This review aims to cover literature up to the end of 2010, describing all the different organocatalytic asymmetric 1,4-conjugate additions even if they are listed as transfer hydrogenation, cycloadditions or desymmetrization of aromatic compounds

Metal perchlorates as Lewis acids: a powerful and versatile tool in organic synthesis

Metal perchlorates are compounds of great chemical interest since they own some unique properties, such as high electronegativity and relatively low charge density, poor complexing ability, high solubility in various organic solvents and kinetic stability under mild conditions. Besides forming polar media when dissolved in solvents, metal perchlorates recently found large employment as Lewis acid promoters in various organic transformations, both in developing new protocols for known and largely used reactions, both in promoting new kinds of reactivity. In this chapter we review our studies and results on the use of metal perchlorates as Lewis acids in various organic reactions under mild reaction conditions, compared with the most important ones appeared in the literature on the same topic. For instance, lithium perchlorate, the most used perchlorate in the past years especially as co-catalyst, proved to be a very efficient promoter for the Friedel Craft acylation of aromatic substrates. On the other hand, small amounts of anhydrous magnesium perchlorate can promote the formation of esters, carbonates and t-butyl ethers from alcohols, the Knoevenagel condensation between \u2013diketones and aldehydes, and multicomponent domino reactions to form functionalized 1,4-tetrahydropyridines. In some cases, such as in the esterification of alcohols with anhydrides and in the conversion of \u2013keto derivatives to the corresponding \u2013enamino derivatives, zinc perchlorate hexahydrate proved to be much more efficient than other Lewis acids. Notably, it is also able to catalyze the Fischer condensation of equimolecular amounts of acids and alcohols. Finally it is important to underline that under mild reaction conditions, i.e. relatively low temperatures and not highly acidic reaction media, metal perchlorates are safe chemical reagents