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BACKGROUND AND PURPOSE In 2016, one person died and four others had mild-to-severe neurological symptoms during a phase I trial of the fatty acid amide hydrolase (FAAH) inhibitor BIA 10-2474. EXPERIMENTAL APPROACH Pharmacodynamic and pharmacokinetic studies were performed with BIA 10-2474, PF-04457845 and JNJ-42165279 using mice, rats and human FAAH expressed in COS cells. Selectivity was evaluated by activity-based protein profiling (APBB) in rats. BIA 10-2474 effect in stroke-prone spontaneously hypertensive rats (SHRSP) was investigated. KEY RESULTS BIA 10-2474 was 10-fold less potent than PF-04457845 in inhibiting human FAAH in situ but inhibited mouse brain and liver FAAH with ED50 values of 13.5 and 6.2 μg·kg-1 , respectively. Plasma and brain BIA 10-2474 levels were consistent with in situ potency and neither BIA 10-2474 nor its metabolites accumulated following repeat administration. FAAH and α/β-hydrolase domain containing 6 were the primary targets of BIA 10-2474 and, at higher exposure levels, ABHD11, PNPLA6, PLA2G15, PLA2G6 and androgen-induced protein 1. At 100 mg·kg-1 for 28 days, the level of several lipid species containing arachidonic acid increased. Daily treatment of SHRSP with BIA 10-2474 did not affect mortality rate or increased the incidence of haemorrhage or oedema in surviving animals. CONCLUSIONS AND IMPLICATIONS BIA 10-2474 potently inhibits FAAH in vivo, similarly to PF-04457845 and interacts with a number of lipid processing enzymes, some previously identified in human cells as off-targets particularly at high levels of exposure. These interactions occurred at doses used in toxicology studies, but the implication of these off-targets in the clinical trial accident remains unclear.

Calcarenite stone samples from a historic building (Bizerte, Tunisia) were collected and treated under different environmental conditions with several consolidating products: alkoxysilane (ethyl silicate), a surfactant-templated novel sol–gel, Ca(OH)2, and SiO2 nanoparticles. These were subjected to marine aerosol accelerated aging cycles and studied by several non-destructive tests and techniques to assess the stability of the products. Results show that weathering caused by salt crystallization is not inhibited but it is slowed down due to the enhancement of superficial mechanical properties (surface cohesion and micro-hardness) achieved after one month of treatments application. A high or low relative humidity of the consolidation environment significantly affects the final mechanical and aesthetical physical properties and therefore conditions the durability of the treated substrates, even producing higher damage than observed in the blank specimens, depending on the product.

Background and Purpose Catechol-O-methyltransferase (COMT) is an important target in the levodopa treatment of Parkinson's disease; however, the inhibitors available have problems, and not all patients benefit from their efficacy. Opicapone was developed to overcome those limitations. In this study, opicapone's pharmacological properties were evaluated as well as its potential cytotoxic effects.

Seven silicate rocks used as ornamental stones and having different surface finishing were submitted to salt fog atmospheres in order to compare different susceptibilities to alteration. Polished, honed, hammered and flamed finishing types were tested. Rocks come from Portugal, Brazil and Angola and are widely commercialized. Samples covered quartz rich rocks, silica saturated and undersaturated rocks, mono and plurimineralic rocks, coarse and fine grained rocks. Mineral composition, texture and open porosity showed to be important parameters which determine mass loss among samples, but the finishing type was very effective within samples. Mass loss and porosity increase are higher on hammered samples, contrasted with the lowest loss values on polished samples. The effect of surface hydrophobicity and roughness on the samples having polished finishing was also analysed by atomic force microscopy (AFM) and water contact angle (WCA), indicating that texture and mineral diversity influence the hydrophobic character of the rock surfaces.

Mediterranean calcarenite stones are exposed to several weathering processes related to the climate and environment, producing alteration features conducing to loss of cohesion in their structures. Samples of these building materials were collected from the Spanish Fort of Bizerte (Tunisia) to carry out laboratory tests in order to assess the consolidation effect of the nowadays most frequently used products and most innovative consolidation materials based in nanoparticles. Stone specimens were consolidated with the most employed alkoxysilane product (ethyl silicate), with a surfactant-templated novel sol-gel product (that avoids the tendency to crack) and with inorganic products based on calcium hydroxide nanoparticles (Ca(OH)) and silica nanoparticles (SiO) under very humid and dry environmental conditions. Samples were characterized by scanning electron microscopy, peeling test, superficial hardness, drilling resistance, water absorption by capillarity and under vacuum, water desorption and spectrophotometry, before and after one month of the application of the products to evaluate their consolidation effect under different environmental conditions. The results show great differences in the consolidation effect and in the changes produced in the physical properties of the substrate after using alkoxysilane products (even nanostructured) or products based in nanoparticles. In the case of alkoxysilane and nanostructured products, especially exposed to high RH conditions, the mechanical properties of the substrate, internal and surface, increase. In both cases a layer on the substrate which occludes the pores is generated maintaining a hydrophobic behavior after one month causing drastic changes in the hydric behavior with visually detectable aesthetic changes. In the case of inorganic nanoparticles, changes in the porosity of the substrate caused by the creation of micropores occur in both cases. In the case of SiO nanoparticles, moderate physical changes occur in dry conditions resulting in less shrinkage and color changes. Finally, Ca(OH) nanoparticles are the products with the lowest surface and internal consolidation effectiveness which barely change the physical properties of the stone., This work has been carried out at Instituto de Geociencias (CSIC,UCM) and supported by Rafael Fort and GEOMATERIALES (S2009/MAT-1629) Program. The work was also supported by a JAE-PreDoc fellowship program (2010–2014) of the Spanish National Research Council (CSIC) and the Adaptability and Employment Program of the European Social Fund (ESF 2007–2013).

The aim of this study is the comparison between different treatments (anatase and two conventional biocides: Biotin T and Anios) for preventing biodeterioration of mortars. The treatments were applied both in the laboratory on mortar slabs and in situ on walls of Palácio Nacional da Pena (Sintra, Portugal). Mortar slabs treated with anatase (pure and Fe3+ doped) applied as a coating or by mixing within the mortar were prepared, and their surfaces characterized by different methodologies. The mortars were inoculated with cyanobacteria and chlorophyta species, incubated for a period of 4 months and the chlorophyll content quantified by extraction method and fluorescence emission. For comparison purposes untreated mortar slabs were inoculated, incubated and finally treated with the biocides. After two weeks the respective chlorophyll contents was quantified.In situ studies in two external walls of Palácio Nacional da Pena covered by organisms were also performed by direct application of aqueous solutions of the three products, and the efficiency of the treatment monitored by spectrophotometry using the CIELAB method. Lichens and other phototrophic microorganisms were identified by direct observation with a microscope and cyanobacteria, green microalgae, bacteria and fungi by DNA-based molecular analysis targeting the 16S and 18S ribosomal RNA genes.The results show that anatase is a better agent for preventing biodeterioration than the two tested conventional biocides, both in mortars slabs and in situ studies. In fact, photographic and colorimetric records made in two external walls of Palácio Nacional da Pena after two weeks of treatments application showed that lichens and other phototrophic microorganisms disappear from the places where anatase was applied. © 2010 Elsevier Ltd., We wish to thank the Departamento de Quimica - REQUIMTE for technical and experimental support. Acknowledge- ments are also due to the CICEGe-FCT/UNL, for SEM-EDX facilities, and to the DCT-FCT/UNL, for the use of the terrace for external conditions experiments. This is a TCP CSD2007-00058 paper.

In this study opicapone´s pharmacological properties were evaluated as well as its potential cytotoxic effects. The pharmacodynamic effects of opicapone were explored by evaluating rat catechol-O-m...

In this work, we present a comparative case study of “ ortho- ” and “ meta -nitrated” catecholic inhibitors of catechol- O -methyltransferase (COMT), with regard to their interaction with the catalytic site of the enzyme and the in vitro regioselective formation of their mono- O -methyl ether metabolites. In particular, the effects of altering the attachment position of the inhibitors9 side-chain substituent, within the classic nitrocatechol pharmacophore, were investigated. For this purpose, we compared two simple regioisomeric nitrocatechol-type inhibitors of COMT, BIA 3-228 and BIA 8-176, which contain the benzoyl substituent attached at the meta and ortho positions, respectively, relative to the nitro group. The two compounds were slowly O -methylated by COMT in vitro, but the particular substitution pattern of each compound was shown to have a profound impact on the regioselectivity of their O -methylation. To provide a plausible interpretation of these results, a comprehensive analysis of the protein-inhibitor interactions and of the relative chemical susceptibility to O -methylation of the catechol hydroxyl groups was performed by means of docking simulations and ab initio molecular orbital calculations. The major structural and chemical factors that determine the enzyme regioselectivity of O -methylation were identified, and the X-ray structure of the complex of COMT with S -adenosyl-l-methionine and BIA 8-176 is herein disclosed. This is the first reported structure of the soluble form of COMT complexed with a nitrocatecholic inhibitor having a bulky substituent group in adjacent position ( ortho ) to the nitro group. Structural and dynamic aspects of this complex are analyzed and discussed, in the context of the present study.

Catechol-O-methyltransferase (COMT, EC 2.1.1.6) plays a central role in the metabolic inactivation of neurotransmitters and neuroactive xenobiotics possessing a catechol motif. 1-(3,4-Dihydroxy-5-nitrophenyl)-2-phenyl-ethanone (BIA 3-202) is a novel nitrocatechol-type inhibitor of COMT, the potential clinical benefit of which is currently being evaluated in the treatment of Parkinson's disease. In the present work we characterize the molecular interactions of BIA 3-202 within the active site of COMT and discuss their implication on the regioselectivity of metabolic O-methylation. Unrestrained flexible-docking simulations suggest that the solution structure of this complex is better described as an ensemble of alternative binding modes, in contrast to the well defined bound configuration revealed by the X-ray structures of related nitrocatechol inhibitors, co-crystallized with COMT. The docking results wherein presented are well supported by experimental evidence, where the pattern of in vitro enzymatic O-methylation and O-demethylation reactions are analyzed. We propose a plausible explanation for the paradoxical in vivo regioselectivity of O-methylation of BIA 3-202, as well as of its related COMT inhibitor tolcapone. Both compounds undergo in vivo O-methylation by COMT at either meta or para catechol hydroxyl groups. However, results herein presented suggest that, in a subsequent step, the p-O-methyl derivatives are selectively demethylated by a microsomal enzyme system. The overall balance is the accumulation of the m-O-methylated metabolites over the para-regioisomers. The implications for the general recognition of nitrocatechol-type inhibitors by COMT and the regioselectivity of their metabolic O-methylation are discussed.

The three-dimensional X-ray structure of cytochrome c3 from a sulfate reducing bacterium, Desulfovibrio desulfuricans ATCC 27774 (107 residues, 4 heme groups), has been determined by the method of molecular replacement [Frazão et al. (1994) Acta Crystallogr. D50, 233-236] and refined at 1.75 A to an R-factor of 17.8%. When compared with the homologous proteins isolated from Desulfovibrio gigas, Desulfovibrio vulgaris Hildenborough, Desulfovibrio vulgaris Miyazaki F, and Desulfomicrobium baculatus, the general outlines of the structure are essentialy kept [heme-heme distances, heme-heme angles, His-His (axial heme ligands) dihedral angles, and the geometry of the conserved aromatic residues]. The three-dimensional structure of D. desulfuricans ATCC 27774 cytochrome c3Dd was modeled on the basis of the crystal structures available and amino acid sequence comparisons within this homologous family of multiheme cytochromes [Palma et al. (1994) Biochemistry 33, 6394-6407]. This model is compared with the refined crystal structure now reported, in order to discuss the validity of structure prediction methods and critically evaluate the steps used to predict protein structures by homology modeling. The four heme midpoint redox potentials were determined by using deconvoluted electron paramagnetic resonance (EPR) redox titrations. Structural criteria (electrostatic potentials, heme ligand orientation, EPR g values, heme exposure, data from protein-protein interaction studies) are invoked to assign the redox potentials corresponding to each specific heme in the three-dimensional structure.