Production, purification, and quality assessment of borrelial proteins CspZ from Borrelia burgdorferi and FhbA from Borrelia hermsii.

Borrelia, spirochetes transmitted by ticks, are the etiological agents of numerous multisystemic diseases, such as Lyme borreliosis (LB) and tick-borne relapsing fever (TBRF). This study focuses on two surface proteins from two Borrelia subspecies involved in these diseases: CspZ, expressed by Borrelia burgdorferi sensu stricto (also named BbCRASP-2 for complement regulator-acquiring surface protein 2), and the factor H binding A (FhbA), expressed by Borrelia hermsii. Numerous subspecies of Borrelia, including these latter, are able to evade the immune defenses of a variety of potential vertebrate hosts in a number of ways.

Synthetic Peptide Antibodies as TNF-α Inhibitors: Molecularly Imprinted Polymer Nanogels Neutralize the Inflammatory Activity of TNF-α in THP-1 Derived Macrophages.

Tumor Necrosis Factor-α (TNF-α) is a cytokine that is normally produced by immune cells when fighting an infection. But, when too much TNF-α is produced as in autoimmune diseases, this leads to unwanted and persistent inflammation. Anti-TNF-α monoclonal antibodies have revolutionized the therapy of these disorders by blocking TNF-α and preventing its binding to TNF-α receptors, thus suppressing the inflammation.

Molecularly Imprinted Polymer Nanogels for Protein Recognition: Direct Proof of Specific Binding Sites by Solution STD and WaterLOGSY NMR Spectroscopies.

Molecularly imprinted polymers (MIPs) are tailor-made synthetic antibodies possessing specific binding cavities designed for a target molecule. Currently, MIPs for protein targets are synthesized by imprinting a short surface-exposed fragment of the protein, called epitope or antigenic determinant. However, finding the epitope par excellence that will yield a peptide "synthetic antibody" cross-reacting exclusively with the protein from which it is derived, is not easy.

The Impact of Plasma Membrane Lipid Composition on Flagellum-Mediated Adhesion of Enterohemorrhagic Escherichia coli.

Enterohemorrhagic (EHEC) O157:H7 is a major cause of foodborne gastrointestinal illness. The adhesion of EHEC to host tissues is the first step enabling bacterial colonization. Adhesins such as fimbriae and flagella mediate this process.

Solid-phase extraction of betanin and isobetanin from beetroot extracts using a dipicolinic acid molecularly imprinted polymer.

Betanin is a natural pigment with significant antioxidant and biological activities currently used as food colorant. The isolation of betanin is problematic due to its instability. In this work, we developed a fast and economic procedure based on molecularly imprinted solid-phase extraction (MISPE) for the selective clean-up of betanin and its stereoisomer isobetanin from beetroot extracts.

Molecularly Imprinted Polymer Coated Quantum Dots for Multiplexed Cell Targeting and Imaging.

Advanced tools for cell imaging are of great interest for the detection, localization, and quantification of molecular biomarkers of cancer or infection. We describe a novel photopolymerization method to coat quantum dots (QDs) with polymer shells, in particular, molecularly imprinted polymers (MIPs), by using the visible light emitted from QDs excited by UV light. Fluorescent core-shell particles specifically recognizing glucuronic acid (GlcA) or N-acetylneuraminic acid (NANA) were prepared.

Plastic Antibodies for Cosmetics: Molecularly Imprinted Polymers Scavenge Precursors of Malodors.

Molecularly imprinted polymers (MIPs) are synthetic antibody mimics capable of specific molecular recognition. Advantageously, they are more stable, easy to tailor for a given application and less expensive than antibodies. These plastic antibodies are raising increasing interest and one relatively unexplored domain in which they could outplay these advantages particularly well is cosmetics.

Triterpenes from the exudate of Gardenia urvillei.

A cycloartane gardurvilleic acid, three 3,4-seco-cycloartanes securvienol, secodienurvilleic acid, securvitriol, a 3,4;9,10-seco-cycloartane gardheptlactone, two dammaranes urvilone, urvilol, along with eight known cycloartanes and 3,4-seco-cycloartanes and four known dammaranes have been isolated from the bud exudate of Gardenia urvillei, an endemic tree to the New Caledonian dry forest. Two other dammarane derivatives have been obtained by semisynthesis. The structures of the original compounds were determined by spectroscopic methods and chemical correlations.

Betanin-Enriched Red Beetroot (Beta vulgaris L.) Extract Induces Apoptosis and Autophagic Cell Death in MCF-7 Cells.

Recent studies have pointed out the preventive role of beetroot extracts against cancers and their cytotoxic activity on cancer cells. Among many different natural compounds, these extracts contained betanin and its stereoisomer isobetanin, which belongs to the betalain group of highly bioavailable antioxidants. However, a precise identification of the molecules responsible for this tumor-inhibitory effect was still required.

Synthetic studies on hemicalide: development of a convergent approach toward the C1-C25 fragment.

Synthetic studies on hemicalide, a recently isolated marine natural product displaying highly potent antiproliferative activity and a unique mode of action, have highlighted a reliable Horner-Wadsworth-Emmons olefination to create the C6-C7 alkene and a remarkable efficient Suzuki-Miyaura coupling to form the C15-C16 bond, resulting in the development of a convergent approach toward the C1-C25 fragment.

Carbene-mediated functionalization of the anomeric C-H bond of carbohydrates: scope and limitations.

Herein we investigate the scope and limitations of a new synthetic approach towards α- and β-ketopyranosides relying on the functionalization of the anomeric C-H bond of carbohydrates by insertion of a metal carbene. A key bromoacetate grafted at the 2-position is the cornerstone of a stereoselective glycosylation/diazotransfer/quaternarization sequence that makes possible the construction of a quaternary center with complete control of the stereochemistry. This sequence shows a good tolerance toward protecting groups commonly used in carbohydrate chemistry and gives rise to quaternary disaccharides with good efficiency.

Relative stereochemical determination and synthesis of the C17-C25 δ-lactone fragment of hemicalide.

Hemicalide is a novel marine metabolite polyketide distinguished by a unique mechanism of action. Because of insufficient quantities of purified material, this natural product has evaded complete stereochemical assignments. Recently, we have determined the relative stereochemistry of the C8-C13 hexad by synthesizing the C1-C13 fragment.

Development of a novel method for quantification of sterols and oxysterols by UPLC-ESI-HRMS: application to a neuroinflammation rat model.

Cholesterol and oxysterols are involved as key compounds in the development of severe neurodegenerative diseases and in neuroinflammation processes. Monitoring their concentration changes under pathological conditions is of interest to get insights into the role of lipids in diseases. For numerous years, liquid chromatography coupled to mass spectrometry has been the method of choice for metabolites identification and quantification in biological samples.

Solvent/base effects in the selective domino synthesis of phenanthridinones that involves high-valent palladium species: experimental and theoretical studies.

The domino reaction of o-bromobenzamides 1a-m in the presence of K(2)CO(3) and the [PdCl(2)(PPh(3))(2)] catalyst granted a selective access to phenanthridinones 2 or to the new 1-carboxamide phenanthridinones 3 depending on the solvent, DMF or 1,4-dioxane, respectively. Investigations of the reaction parameters provided the first example of a direct correlation between the base dissociation and the solvent polarity on the selectivity observed. Moreover, mechanistic studies (NMR spectroscopy and ESI-MS monitoring) allowed us to characterize Pd(II) palladacycle 4 and biaryl species as common intermediates for these two domino processes.

Fluorinated diaminocyclopentanes as chiral sensitive NMR probes of RNA structure.

The supramolecular chiral recognition between rac-2a and several structured RNA leads to a distinct (19)F NMR signal splitting. The (19)F NMR analysis of the diastereomeric pairs formed upon binding of this racemic probe delivers a topological footprint of the RNA. This phenomenon can be exploited to investigate dynamic events involving structural equilibria, as demonstrated in a melting experiment.

Synthesis and biological evaluation of new penta- and heptacyclic indolo- and quinolinocarbazole ring systems obtained via Pd(0) catalysed reductive N-heteroannulation.

A short route, involving a tetramolecular condensation reaction and a Pd/C catalyst-H(2)-mediated reductive N-heteroannulation as the key-steps, has been found for the synthesis of some new penta- and heptacyclic indolo- (12), quinolino- (13) and indoloquinolinocarbazole (11) derivatives. HF-DFT (B3LYP) energy profiles and NMR calculations were carried out to help in the understanding of the experimental results. N-Alkylated indoloquinolinocarbazoles (16b, 17a, 17b and 18) were prepared and screened essentially toward some cancer-(G-quadruplex, DNA, topoisomerase I) and CNS-related (kinases) targets.

New ifosfamide analogs designed for lower associated neurotoxicity and nephrotoxicity with modified alkylating kinetics leading to enhanced in vitro anticancer activity.

Ifosfamide is a well known prodrug for cancer treatment with cytochrome P450 metabolism. It is associated with both antitumor activity and toxicities. Isophosphoramide mustard is the bisalkylating active metabolite, and acrolein is a urotoxic side product.

Structural and antitumor properties of the YSNSG cyclopeptide derived from tumstatin.

We previously demonstrated that the NC1[alpha3(IV)185-191] CNYYSNS peptide inhibited in vivo tumor progression. The YSNS motif formed a beta turn crucial for biological activity. The aim of the present study was to design a YSNSG cyclopeptide with a constrained beta turn on the YSNS residues more stable than CNYYSNS.

Novel seco-dibenzopyrrocoline alkaloid from Cryptocarya oubatchensis.

[structure: see text] A novel seco-dibenzopyrrocoline alkaloid, named oubatchensine 6, and five phenanthroindolizidines (1-5) were isolated from Cryptocarya oubatchensis, and their structures were elucidated. Displacement centrifugal partition chromatography was used to purify compounds 1 and 6. Structure determination of the latter was carried out by mass spectrometry, NMR spectroscopy, quantum chemistry, and computer-assisted structure determination.

Complete 1H- and 13C NMR assignments of saponins from roots of Gypsophila trichotoma Wend.

The assignments of 1H and 13C NMR spectra of two new aminoacyl triterpene saponins from roots of Gypsophila trichotoma Wend. are reported. In addition to 1D NMR methods, 2D NMR techniques (COSY, TOCSY, ROESY, HSQC, HMBC, and HSQC-TOCSY) were used for the assignments.

Five labdane diterpenoids from the seeds of Aframomum zambesiacum.

Five labdane diterpenoids, (3-5), zambesiacolactone A (7) and zambesiacolactone B (8), were isolated from the seeds of Aframomum zambesiacum (Baker) K. Schum., along with five known labdanes and a linear sesquiterpene, nerolidol.

Origin of chiral induction in radical reactions with the diastereoisomers (5R)- and (5S)-5-l-menthyloxyfuran-2[5H]-one.

Acetalization of 5-hydroxyfuran-2[5H]-one with l-menthol yields (5R)- (1) and (5S)-5-l-menthyloxyfuran-2[5H]-one (2) in equal amounts. The diastereomer 1 crystallizes preferentially. For the first time, the isolation of pure diastereoisomer 2 is reported.

Chrysopentamine, an antiplasmodial anhydronium base from Strychnos usambarensis leaves.

A new derivative of strychnopentamine was isolated from the leaves of Strychnos usambarensis. This compound, named chrysopentamine, was identified by detailed spectroscopic methods (UV, IR, HR-ESI-MS, 1D and 2D NMR). Chrysopentamine presented an original hydroxy substitution on C-14 and an aromatization of the ring D of strychnopentamine leading to anhydronium base properties and exhibited strong antiplasmodial properties (IC (50) less than 1 microM).

Diffusion coefficient of CO(2) molecules as determined by (13)C NMR in various carbonated beverages.

In this paper, the NMR technique was used, for the first time, to accurately determine the diffusion coefficient D of CO(2)-dissolved molecules in various carbonated beverages, including champagne and sparkling wines. This parameter plays an important role concerning the bubble growth during its rise through the liquid (see ref 3). The diffusion coefficient of CO(2)-dissolved molecules D was compared with that deduced from the well-known Stokes-Einstein equation and found to significantly deviate from the general trend expected from Stokes-Einstein theory, i.