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Our results clearly indicate that polyphenols protect human derived cells against DNA strand breaks and oxidative DNA damage effects of NDMA, NPYR or BaP, three carcinogenic compounds which occur in the environment.

Ischemie changes in 31 samples of lateral retmacula excised at surgical realignment in patients with isolated symptomatic patellofemoral malalignment resistant to conservative treatment were evaluated with conventional histology, electron microscopy, immunohistochemistry, and molecular biology. Morphologic and ultrastructural changes associated with ischemia including hypervascularization and increased vascular endothelial growth factor release were identified in painful patellofemoral malalignment. It is hypothesized that periodic short episodes of ischemia could be implicated in the pathogenesis of anterior knee pain in most cases of isolated symptomatic patellofemoral malalignment in active young patients by triggering neural proliferation.

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Solute binding proteins (SBPs) form a heterogeneous protein family that is found in all kingdoms of life. In bacteria, the ligand-loaded forms bind to transmembrane transporters providing the substrate. We present here the SBP repertoire of Pseudomonas aeruginosa PAO1 that is composed of 98 proteins. Bioinformatic predictions indicate that many of these proteins have a redundant ligand profile such as 27 SBPs for proteinogenic amino acids, 13 proteins for spermidine/putrescine, or 9 proteins for quaternary amines. To assess the precision of these bioinformatic predictions, we have purified 17 SBPs that were subsequently submitted to high-throughput ligand screening approaches followed by isothermal titration calorimetry studies, resulting in the identification of ligands for 15 of them. Experimentation revealed that PA0222 was specific for γ-aminobutyrate (GABA), DppA2 for tripeptides, DppA3 for dipeptides, CysP for thiosulphate, OpuCC for betaine, and AotJ for arginine. Furthermore, RbsB bound D-ribose and D-allose, ModA bound molybdate, tungstate, and chromate, whereas AatJ recognized aspartate and glutamate. The majority of experimentally identified ligands were found to be chemoattractants. Data show that the ligand class recognized by SPBs can be predicted with confidence using bioinformatic methods, but experimental work is necessary to identify the precise ligand profile.Chemosensory signal transduction has been extensively studied in Escherichia coli [2] that has four chemoreceptors with a periplasmic ligand binding domain (LBD) and an aerotaxis receptor that senses signals in the cytosol. Chemoreceptors can be stimulated by direct signal binding to the LBD and/or by the recognition of signal loaded solute binding proteins (SBPs) [6]. Interestingly, all four E. coli chemoreceptors can be stimulated by SBP binding causing chemotaxis to sugars, dipeptides, and autoinducer-2 [7-10].Many other bacteria contain more chemoreceptors, which are mostly of unknown function [11,12], and significant efforts are being made by the scientific community to identify the ligands they recognize. Among the model organisms to study chemoreceptors is the human pathogen Pseudomonas aeruginosa PAO1 that has 26 chemoreceptor genes [13]. The functions of a significant number of P. aeruginosa chemoreceptors has been identified and receptors for amino acids and GABA [14,15], polyamines and histamine [16], nitrate [17], α-ketoglutarate [18], or inorganic phosphate [19,20] have been reported. However, screening experiments using ligand libraries have failed to identify ligands that bind to many other P. aeruginosa chemoreceptors. This may indicate that the ligand(s) is (are) not contained in the compound library used for screening or, alternatively, that the receptor is activated by the binding of signal-loaded SBPs. The abundance of SBP mediated chemoreceptor activation in E. coli, the failure to identify directly binding ligands for P. aeruginosa chemoreceptors and the evidence for SBP mediated chemoreceptor activation in other spec...