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In this study, graphitic carbon nitride (g-C3N4) was successfully coupled with TiO2 using hydrothermal method, to develop an advanced heterojunction photocatalyst. The interaction between g-C3N4 and TiO2 was confirmed through analysis of X-Ray spectroscopy (XPS) C 1s, N 1s, O 1s high resolution core level spectra of g-C3N4, TiO2 and g–C3N4–TiO2 heterojucntion. Further, through valence band spectra analysis, conduction band offset (0.12 eV) and valence band offset (0.28 eV) of g–C3N4–TiO2 heterojunction were estimated. Also, composite material was identified as type II heterojunction between g-C3N4 and TiO2. XRD, UV–vis, BET and HRTEM were employed to understand the changes in physicochemical properties. Photocatalytic hydrogen production rates were evaluated through water splitting experiments. Under visible light irradiation highest hydrogen production rate was achieved for g–C3N4–TiO2 heterojunction sample with high content of TiO2, and was about 1041 μmol/g.h. The improved photocatalytic activity of the heterojunction material was explained in detail.

Nowadays there is a worldwide growing interest in the Inkjet Printing technology owing to its potentially high levels of geometrical complexity, personalization and resolution. There is also social concern about usage, disposal and accumulation of plastic materials. In this work, it is shown that sugar-based biodegradable polyurethane polymers exhibit outstanding properties as polymer-matrix for gold nanoparticles composites. These materials could reach exceptional stabilization levels, and demonstrated potential as novel robust inks for Inkjet based Printing. Furthermore, a physical comparison among different polymers is discussed based on stability and printability experiments to search for the best ink candidate. The University of Seville logo was printed by employing those inks, and the presence of gold was confirmed by ToF-SIMS. This approach has the potential to open new routes and applications for fabrication of enhanced biomedical nanometallic-sensors using stabilized AuNP. Spanish Ministerio de Economía y Competitividad MINECO, (Grants Nos. CTQ2016- 78703-P and MAT2016-78703-P) Junta de Andalucía (Consolidation Grant for Research Group FQM135 and 2017/FQM-386, P-2018/809) University of Seville (V y VI Plan Propio PP2016-5937)

In photocatalysis, surface engineered CeO2 could be vital due to oxygen vacancies arise from multiple valency, i.e. Ce3+ and Ce4+. This study reports photocatalytic properties of g-C3N4/CeO2 composite synthesized by a facile method in the presence of l-arginine. Physicochemical properties of g-C3N4/CeO2 material were analyzed through various characterization techniques such as XRD, UV–Vis, physisorption, etc., and correlated with its photocatalytic activity. Observed bandgap of the synthesized composite material was in the visible region, around 2.8 eV which is less than that of typical ceria, but higher than bandgap of exfoliated g-C3N4. On the further side, N doping into CeO2 was confirmed through XPS analysis. It is estimated that synthesis method aided for the N doping, which further played key role in lowering the bandgap of g-C3N4/CeO2 composite. Finally, Photocatalytic activity of g-C3N4/CeO2 composite was analyzed through degradation of an herbicide i.e. diuron, and the study revealed the good performance of the catalyst. Keywords: CeO2, Graphitic carbon nitride, Photocatalysis, N doping, Herbicide

In this work, a novel combination of designed heat treatments and cold work performed on Al-6063 alloy was proposed. The consumption of aluminium and its alloys in the automotive and aeronautic industries has increased over the past few years, in the same way, as the consumption of material for manufacturing moulds for casting of plastic parts and dies for plastics and metals. Then, it is important to find a low-cost alternative to maximise the mechanical properties of aluminium, with a negligible effect on the ductility of the alloy, which is important due to thermal and mechanical fatigue on mould and dies. It is well known that precipitation hardening increases the mechanical and yield strength of aluminium alloys with a major ductility loss. However, the developed methodology consists of a solution heat treatment, followed by cold working (strain hardening), and lastly a heat treatment (precipitation hardening and stress reliever) to produce Al 6063 aluminium alloys with enhanced mechanical strength and with a negligible ductility loss. The proposed methodology increases around 23.45% of the tensile and yield strength, with a ductility reduction of less than 1.5% in the elastic materials region. The experimental tensile testing results are correlated with nanoindentation experimental results in order to confirm that the level of cold working is directly proportional to mechanical strength levels by two different characterisation techniques at a macro- and nanoscales, respectively.

In this work, an alternative statistical multiple linear robust regression methodology was used to analyze the experimental data obtained from tensile tests performed on heat treated samples of an aluminium 6063 alloy. The proposed methodology allows the identification of empirical relations between the ageing temperature and process time with the mechanical strength (UTS) and yield point (YS) of the alloy. Through these empirical relationships: a) $$ UTS=0.0932{T}_a{t}_A-0.1356{t}_A^2-0.0002434{T}_a^2{t}_A+0.00063{t}_A^3 $$ and b) $$ YS=5.10{T}_a-20.32{t}_A-0.05281{T}_a^2+0.2297{T}_a{t}_A+0.0001459{T}_a^3-0.0006192{T}_a^2{t}_A $$ , obtained by using the multiple linear robust regression methodology, it was possible to find that an ageing temperature of 192 °C for 120 min would produce the maximum strength levels for the Al-6063 alloy. For such alloy, empirical relationships were successfully determined for ageing heat treatment design.

This article presents a novel unit that integrates for the first time air sampling and preconcentration based on the use of fabric phase sorptive extraction principles. The determination of Tuta absoluta sexual pheromone traces in environmental air has been selected as analytical problem. For this aim, a novel laboratory-built unit made up of commercial brass elements as holder of the sol-gel coated fabric extracting phase has been designed and optimized. The performance of the integrated unit was evaluated analyzing environmental air sampled in tomato crops. The unit can work under sampling and analysis mode which eliminates any need for sorptive phase manipulation prior to instrumental analysis. In the sampling mode, the unit can be connected to a sampling pump to pass the air through the sorptive phase at a controlled flow-rate. In the analysis mode, it is placed in the gas chromatograph autosampler without any instrumental modification. It also diminishes the risk of cross contamination between sampling and analysis. The performance of the new unit has been evaluated using the main components of the sexual pheromone of Tuta absoluta [(3E,8Z,11Z)-tetradecatrien-1-yl acetate and (3E,8Z)-tetradecadien-1-yl acetate] as model analytes. The limits of detection for both compounds resulted to be 1.6 μg and 0.8 μg, respectively, while the precision (expressed as relative standard deviation) was better than 3.7%. Finally, the unit has been deployed in the field to analyze a number of real life samples, some of them were found positive.

In this work, aluminium 6061 alloy samples were subjected to a 5% CH3COOH pressurized oxidizing steam process and to sequential heat treatments. The heat treatments effect on the ultimate tensile strength UTS , yield strength YS , and its correlation with the corrosion current density i corr and the corrosion potential E corr , along with the coating formed on the alloy surface were characterized. Empirical equations were developed in order to describe the behavior and correlation among the process parameters on the YS , UTS , i corr and E corr . The X-ray diffraction XRD and the Energy Dispersive Spectroscopy EDS were used to characterize the chemical composition of the oxide layer formed after the oxidizing steam process and the designed heat treatments. Chemical reactions were proposed following the EDS results and the reactants (alloy and steam), finding the formation of aluminium carbonate Al 2 ( CO 3 ) 3 , which is unstable and decomposes in α − Al 2 O 3 alumina as the main phase, and the potential formation of a periclase oxide type ( MgO ) and a spinel oxide type ( MgAl 2 O 4 ) as the trailing phases, deposited on the material surface. According to the potentiodynamic polarization test results, the coated samples subjected to ageing (200 °C)-retrogression (250 °C)-reageing (150 °C) heat treatment showed an enhancement on its corrosion resistance without significant losses in the mechanical properties, when compared to the aluminium 6061-T6 alloy condition.

The synthesis and characterization of new highly biodegradable multipropargyl and comb-like copolyurethanes have been successfully achieved by the combination of step-growth polymerization and click chemistry. This work discloses a simple, accurate, and straightforward method to generate brush polymers with an excellent control of the branch nature, distribution, and density in the final materials. The introduction of controlled branching has led to a great variety of polymers, whose hydrophilic/lipophilic characters were adjusted as required. Furthermore, their stiffness, semicrystalline nature, and degradability were fine-tuned by appropriate selection of the monomers and their feed ratios. The presence of propargyl functional groups in the (co)polymers was confirmed by the presence of a thermal degradation step in the range from 450 °C to 455 °C. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016

Bactrocera oleae Gmelin, also known as olive fruit fly, is the main olive tree pest. It produces a severe effect not only on the productivity but also on the quality of the olive-related products. In fact, the oil obtained from infected olives has a lower antioxidant power. In addition, an increase of the oil acidity, peroxide index and UV-absorbance can also be observed. 1,7-dioxaspiro-[5,5]-undecane (DSU), is the main component of the sexual pheromone of this pest and may be used as marker of the pest incidence. In this context, the development of new methods able to detect the pheromones in several samples, including agri-food or environmental ones, is interesting. In this work, we synthesized a molecularly imprinted polymer (MIPS) layer over magnetic nanoparticles (Fe3O4@SiO2@MIP) for the selective recognition of DSU. They were prepared using DSU as template and 3-aminopropyltriethoxysilane (APTES) to associate the target analyte on the surface of the magnetic substrate and the later polymerization of ethylene glycol dimethacrylate (EGDMA) in presence of 2,2-azobisisobutyonnitrile (AIBN). The resulting Fe3O4@SiO2@MIP composite was characterized by different techniques. The maximum adsorption capacity of DSU on Fe3O4@SiO2@MIP in hexane was 32mg/g (5.3 times than that obtained for the non-imprinted composite). In addition, Fe3O4@SiO2@MIP showed a short equilibrium time (45min) and potential reusability. The combination of dispersive magnetic microsolid phase extraction and gas chromatography with mass spectrometric detection allows the determination of DSU in real samples at concentrations as low as 10μg/L with precision better than 7.5% (expressed as relative standard deviation). The relative recoveries are in the range between 95 and 99%, which indicates the potential of the methodology. Finally, it has been applied to real olive oil samples being the presence of the pest detected is some of them.

In the present work, the relation between ageing and retrogression temperatures on Al 6061 alloy hardness and ultimate tensile strength (UTS) was studied. It was found that higher UTS and hardness were obtained at higher ageing, retrogression temperatures, and lowest retrogression time. Controlling these parameters, alloy UTS has been improved 12% over T6 temper, showing a 40% reduction in time consumption during the thermal treatment. By means of a multiple linear regression method, a correlation has been established between UTS, hardness, and time/temperature for ageing and retrogression regimes, This correlation can be used to select adequate ageing temperature and retrogression time-temperature in order to obtain both specific UTS and hardness on aluminium 6061 alloy.

Porous titanium substrates coated by dripping-sedimentation technique with a novel bilayer of (45S5 / 1393) bioactive glasses are proposed to overcome some limitations of the use of titanium for implants, such as the stress shielding and the poor osseointegration. Composition, thickness, roughness and micromechanical behavior (P-h curves) of the coating and the influence of the porous titanium substrates have been characterized. Best results were found for the substrate with 30 vol.% of porosity and a range size of 355 ‒ 500 μm, since it enhanced the mechanical and biofunctional behavior, due to the good adhesion of the 1393 bioglass to the substrate and the greater bioactivity of the 45S5 bioglass, which would be in contact with the bone.

Introduction: Some studies report that exogenous surfactant administration has positive effects in asthma animal models as well as in asthma patients. We have previously shown that Beractant induces an antifibrotic phenotype in normal human lung fibroblasts and that phosphatidylethanolamine (PE) promotes this effect. Therefore, we aimed to assess the effect of a preparation of Beractant enriched with PE on matrix deposition in an experimental model of airway remodeling. Materials and Methods: Beractant enriched with PE (Beractant-PE) was prepared by adding the phospholipid at a final concentration of 0.75 mg mL-1. The experimental model was based on the one reported by Fraga-Iriso et al. (Arch Bronconeumol. 2009; 45(9):422–428). BALB/c mice were sensitized to crude egg extract (CEE) and challenged with inhaled CEE 3 times per week for 12 weeks. Beractant-PE (400 mg kg-1) (6 mice) or vehicle (18 mice) were administered via aerosol with a micronebulizer one hour before the CEE challenges. Animals were sacrificed and lung tissue samples were stained with Masson’s trichrome. The blue stained area (representative of connective tissue) was measured with the image J software by three blinded observers. Results: Measurements among observers had an intraclass correlation coefficient of 0.83. Mean fibrosis area in the positive controls was 0.78 ± 0.77 while in Beractant-PE treated animals was 0.28 ± 0.16 (p Conclusion: Inhaled Beractant-PE attenuates the fibrosis induced by prolonged allergen exposure in mice.

The present work describes the preparation of stable organic nanoparticles with potential use as “smart” drug delivery systems capable of encapsulating lipophilic molecules to exert their therapeutic action under the appropriate stimulus. A well-defined self-assembly hydrophilic-hydrophobic di-block copolymer has been synthesized via atom transfer radical polymerization (ATRP). The hydrophilic block is based on a random copolymer with DMA and HEMA units, while the hydrophobic component is a linear random copolymer of DEA and FMA. Stabilization of the nanoparticles by means of core cross-linking is addressed by Diels-Alder reactions between the furan rings of the hydrophobic blocks and the synthesized bisdienophiles; the influence of both the cross-linking agent and the degree of cross-linking in the process is discussed. The incorporation of a therapeutic agent (pilocarpine) and a lipophilic fluorescent molecule (pyrene) is evaluated. When pyrene was immersed into the micelles, there was a significant boost of the fluorescence emission (from 10- to 40-fold), due to the hydrophobic environment of the inner part of the nanoparticles. Pilocarpine is also able to be encapsulated by the prepared systems. Drug release is triggered by a reduction in the pH of the media and is strongly dependent on the degree of cross-linking achieved., We thank the Junta de Andalucía (Grant P12-FQM-1553) of Spain for financial support.

An improved method for the tert-butanesulfinylation of diacetone glucose with tert-butanesulfinyl chloride is reported. The method is based on a beneficial effect of catalytic DMAP, which enhances both the rate of the reaction and the enantioselectivity of the process to give (RS)-diastereomer 2RS with a 94 % de and in quantitative yield. (RS)-DAG sulfinate ester 2RS is an excellent intermediate for the synthesis of enantiopure tert-butyl sulfoxides. Grignard agents and organolithium reagents can displace smoothly the diacetone glucose moiety to give synthetically relevant enantiopure sulfoxides, including highly functionalized derivatives, in high yields and with high enantioselectivities. (RS)-DAG sulfinate ester 2RS is also an excellent N-sulfinylating agent; simple addition of LiHMDS (lithium hexamethyldisilazide) in THF gives (SS)-tert-butanesulfinamide, and N-tert-butanesulfinylimines are then formed in a two-step one-pot manner. N-Alkylated tert-butanesulfinamides are formed by the condensation of 2RS with lithium amides.

A portable device that integrates sampling and extraction is proposed in this work. The unit is fabricated using commercial and standardized elements which guarantees the construction reproducibility. Also, it is simple to be mounted and on-site deployed making possible the multi-site sampling. The device uses a commercial nylon membrane as extraction phase for the isolation of the target compounds, but it can be adapted to other flat sorptive phases thus expanding the applicability. Once mounted, the unit is stirred into the sample by means of a portable drill enhancing in that way the diffusion of the target analyte towards the extraction phase. The hydrodynamic behavior and the design have been optimized and the device has been finally used for the extraction benzophenones from swimming pool samples. These endocrine disruptive compounds are determined by liquid chromatography tandem mass spectrometry (LC–MS/MS) at concentrations as low as 0.1 μg/L with precision, expressed as relative standard deviation, better than 9.9%. The accuracy, calculated as relative recovery, was in the range from 74 to 111 % thus being considered appropriate.

In the present article, a novel extraction/stirring approach in the liquid phase microextraction context is presented. The new technique is based on octadecyl coated borosilicate disks which act as support of the organic extracting solvent thanks to hydrophobic interactions. The disk is integrated in a stirring element which favors the transference of the analytes to the extraction phase. The proposed extraction procedure has been characterized using the determination of nine herbicides in water samples by ultra performance liquid chromatography (UPLC) combined with ultraviolet (UV) detection as model analytical problem. All the variables involved in the extraction have been studied and optimized in depth and the optimized technique provides enrichment factors in the range from 79 to 839. The method has been analytically characterized on the basis of its linearity, sensitivity and precision. Limits of detection were in the range from 0.14 μg/L (atrazine) to 0.56 μg/L (terbumeton) with precision better than 7.3% (expressed as relative standard deviation). Relative recoveries were close to 100%, which demonstrated the applicability of the stir octadecyl-modified borosilicate disk for the proposed analytical problem.

In this article, magnetically confined hydrophobic nanoparticle microextraction is applied for the analysis of parabens in water samples by gas chromatography (GC)–mass spectrometry (MS). The hydrophobic magnetic nanoparticles (MNPs) are confined in a device by means of a mini-magnet which also allows the stirring of the unit. A thin layer of MNPs, which presents an optimal surface to volume ratio, is the responsible of the analytes extraction. Although the superficial area of the layer is lower than the potential one obtained with a perfect dispersion of the MNPs, the latter approach is hard to be performed with highly hydrophobic MNPs and therefore the proposed configuration is more useful from a practical point of view. This fact, together with the inherent stirring of the unit, enhances the kinetic extraction and therefore the sensitivity of the procedure compared to conventional dispersion conditions. The most influential extraction parameters were evaluated, including the pH and ionic strength of the sample, the stirring rate, the extraction time, the amounts of MNPs, the volume of sample and the elution conditions. Under the most favorable extraction parameters, the method showed good linearity, repeatability (relative standard deviation below 7.1%, n = 7) and sensitivity in the ng per liter range. The proposed method was demonstrated to be a simple, fast and efficient method for the analysis of parabens in sea and swimming pool water samples.

In this article, a solid-phase extraction approach, which takes advantage of the good extraction capabilities of hydrophobic magnetic nanoparticles (MNPs), is presented. The new approach involves the deposition of a thin layer of MNPs in a dedicated stirring unit based on the dual function of a mini-magnet. The system allows the extraction of the analytes in a simple and efficient way. The approach, which reduces the negative effect of the aggregation tendency of hydrophobic MNPs, is characterized for the resolution of a model analytical problem: the determination of some endocrine-disrupting phenols in water by liquid chromatography-photometric detection. All the variables involved in the extraction process have been clearly identified and optimized. The new extraction mode allows the determination of these compounds with limits of detection in the range from 0.15 μg/L (for 4-tert-octylphenol) to 2.7 μg/L (for 4-tert-butylphenol) with a relative standard deviation lower than 5.3 % (for 4-tert-butylphenol).

Retinitis pigmentosa (RP), the most frequent form of inherited retinal dystrophy is characterized by progressive photoreceptor degeneration. Many genes have been implicated in RP development, but several others remain to be identified. Using a combination of homozygosity mapping, whole-exome and targeted next-generation sequencing, we found a novel homozygous nonsense mutation in SAMD11 in five individuals diagnosed with adult-onset RP from two unrelated consanguineous Spanish families. SAMD11 is ortholog to the mouse major retinal SAM domain (mr-s) protein that is implicated in CRX-mediated transcriptional regulation in the retina. Accordingly, protein-protein network analysis revealed a significant interaction of SAMD11 with CRX. Immunoblotting analysis confirmed strong expression of SAMD11 in human retina. Immunolocalization studies revealed SAMD11 was detected in the three nuclear layers of the human retina and interestingly differential expression between cone and rod photoreceptors was observed. Our study strongly implicates SAMD11 as novel cause of RP playing an important role in the pathogenesis of human degeneration of photoreceptors. This work was supported by several grants from the Spanish Centre for Biomedical Network Research on Rare Diseases (CIBERER)(06/07/0036), Instituto de Salud Carlos III (ISCIII, Spanish Ministry of Health)/FEDER, including FIS (PI013/00226) and RETICS (RD09/0076/00101 and RD12/0034/0010), Ministry of Economy and Competitiveness (MINECO), including FEDER (BFU2012-36845), and BIO2011-27069, Conselleria de Educació of the Valencia Community (PROMETEOII/2014/025), Spanish National Organization of the Blind (ONCE) and the Spanish Fighting Blindness Foundation (FUNDALUCE). M.C. was sponsored by the Miguel Servet Program for Researchers in the Spanish National Health Service (CP12/03256) and RSA by Sara Borrel Postdoctoral Program (CD12/00676), both from the ISCIII/FEDER. A.A-F. was sponsored by CIBERER, RPC is supported by Fundación Conchita Rábago (FCR), L.C is sponsored by RETICS (RD12/0034/0010) from ISCIII and L.d.S. was supported by CAPES Foundation, Ministry of Education of Brazil.

In this article, a novel extraction approach, called stir frit microextraction (SFME), is presented. The new approach combines the extractive capability of a commercial polyethylene frit (20 μm of pore size) with the stirring in the same device. The proposed extraction procedure allows the determination of benzene, toluene, ethylbenzene, xylene isomers and styrene (BTEX-S) in water samples. The analytes are extracted on the frit, previously conditioned with methanol, under continuous magnetic stirring. Once the extraction is performed, the frit is transferred to a headspace vial where the volatile compounds are desorbed from the frit (90 °C, 30 min) in a headspace module and analyzed by gas chromatography/mass spectrometry. Headspace conditions (time and temperature) as well as extraction conditions (ionic strength, type of stirring, extraction time, stirring rate and sample volume) have been systematically evaluated. The method was characterized on the basis of its linearity, sensitivity and precision. Limits of detection were in the range from 18 ng/L (o-xylene) to 65 ng/L (benzene). The repeatability of the proposed method, expressed as relative standard deviation (RSD) varied between 3.8% (toluene) and 8.2% (m- and p-xylene). The recovery study carried out in different water samples provided an average recovery of 94%, which demonstrated the applicability of the stir frit microextraction for the analytical problem selected in this article.

A stir membrane liquid phase microextraction procedure working under the three-phase mode is proposed for the first time for the determination of six anti-inflammatory drugs in human urine. The target compounds are isolated and preconcentrated using a special device that integrates the extractant and the stirring element. An alkaline aqueous solution is used as extractant phase while 1-octanol is selected as supported liquid membrane solvent. After the extraction, all the analytes are determined by liquid chromatography (LC) with ultraviolet detection (UV). The analytical method is optimized considering the main involved variables (e.g., pH of donor and acceptor phases, extraction time, stirring rate) and the results indicate that the determination of anti-inflammatory drugs at therapeutic and toxic levels is completely feasible. The limits of detection are in the range from 12.6 (indomethacin) to 30.7 μg/L (naproxen). The repeatability of the method, expressed as relative standard deviation (RSD, n = 5) varies between 3.4 % (flurbiprofen) and 5.7 % (ketoprofen), while the enrichment factors are in the range from 35.0 (naproxen) to 72.5 (indomethacin).

A simple and rapid method for the determination of eleven phenols in water samples is presented. The target analytes are isolated by stir membrane liquid–liquid microextraction working under the three-phase mode. An alkaline aqueous solution is used as extractant phase while octanol is selected as supported liquid membrane solvent. The target analytes are separated and determined by liquid chromatography (LC) with ultraviolet detection (UV). All the variables involved in the extraction process have been studied in depth. Low detection limits (in the range from 82.1 ng/L for phenol to 452 ng/L for 2,4,5-trichlorophenol) were obtained. The repeatability, expressed as relative standard deviation (RSD), varied between 1.3% (for 4-nitrophenol) and 8.0% (for 4-chlorophenol). The enrichment factors were in the range from 168 (for 2,4,5-trichlorophenol) to 395 (for 3-chlorophenol). The proposed procedure was applied for the direct determination of the eleven phenols in some real water samples including river, well and tap waters. The accuracy was evaluated by means of a recovery study, the results being in the range of 87–120%.

In this article, a novel liquid phase microextraction technique, called stir membrane liquid–liquid microextraction (SM-LLME), is presented. The new approach combines the advantages of liquid phase microextraction and stirring in the same unit allowing the isolation and preconcentration of the analytes in a simple and efficient way. In the construction of the unit, a polymeric membrane is employed to protect the small volume of the extractant phase. The extraction technique is characterized for the resolution of a model analytical problem: the determination of five selected chlorophenols in water. A two-phase extraction mode is used for the extraction of the analytes with an organic solvent in which an in situ derivatization reaction takes place. The analytes are finally analyzed by gas chromatography/mass spectrometry. All the variables involved in the extraction process have been clearly identified and optimized. The new extraction mode allows the determination of chlorophenols with limits of detection in the range from 14.8 ng/L (for 2,4,5-trichlorophenol) to 22.9 ng/L (for 3-chlorophenol) with a relative standard deviation lower than 8.7% (for 2,6-dichlorophenol).

The adaptive response of endothelial cells to hypoxia involves a substantial remodeling of extracellular matrix (ECM). In endothelial cells hypoxia up-regulates lysyl oxidase (LOX), a key enzyme in ECM assembly, relevant to vascular homeostasis. However, the mechanism underlying this response has not been established. Hypoxia up-regulated LOX expression in endothelial cells (HUVEC and BAEC) and concomitantly increased LOX enzymatic activity. This effect was independent of autocrine factors released by hypoxic cells and relies on a transcriptional mechanism. Both mTOR blockade and HIF-1alpha knockdown slightly prevented LOX up-regulation by hypoxia, suggesting that HIF-1alpha is only partially responsible for this effect. In fact, serial promoter deletion and mutagenesis studies indicated a limited contribution of the previously described hypoxia response element (-75 bp). Interestingly, Smad over-expression further increased LOX transcriptional activity in endothelial cells exposed to hypoxia. Moreover, the increase in LOX expression triggered by hypoxia was significantly reduced by reactive oxygen species (ROS) inhibitors. Thus, our data support a role of Smad signaling and ROS in the up-regulation of LOX by hypoxia in endothelial cells.

Various chiral secondary alcohols have been used to study the dependence of the stereochemical outcome of sulfinate and phosphinate ester synthesis on the nature of the base used to catalyse the reaction. From this study it has been shown that the achiral stereodirecting base effect determined in the DAG methodology is a general behaviour in the asymmetric synthesis of sulfinate and phosphinate esters.

In this paper, the direct coupling between stir membrane extraction and infrared spectroscopy working under transmission mode is presented for the sensitive and selective determination of the total hydrocarbon index in waters. For this purpose, a new extraction unit was built using stainless steel in order to maximize the adsorption of the target analytes in the 40-microm-thick polytetrafluoroethylene membrane. The method allows the determination of hydrocarbons in the presence of grease, using hexadecane and stearic acid as model compounds, respectively. The proposal is optimized in depth, taking into account the main experimental variables such as membrane thickness, extraction time, and stirring and sample volume. Later on, the method was characterized on the basis of its linearity, precision, and limits of detection. The combination allows the determination of the hydrocarbon index with a limit of detection of 18 microg L(-1), the precision being (expressed as relative standard deviation) better than 4.3%. The analytical method provides a high sample throughput since some extractions can be performed in parallel, the relative standard deviation between devices being better than 8%. The proposed analytical method is finally compared in terms of analytical figures with counterpart ASTM method, recently presented.

In this work, we review the clinical and genetic data in 14 Latin American propionic acidemia (PA) and 15 methylmalonic aciduria (MMAuria) patients. In the PA patients, we have identified four different changes in the PCCA gene, including one novel one (c.414+5G>A) affecting the splicing process. The PCCB mutational spectrum included two prevalent changes accounting for close to 60% of the mutant alleles studied and one novel change (c.494G>C) which by functional analysis is clearly pathogenic. We have also identified the deep intronic change c.654+462A>G, and the results of the antisense treatment in the patient's cell line confirmed the functional recovery of PCC activity. All PA patients bearing out-of-frame mutations presented the disease earlier while patients bearing in hemizygous fashion p.E168K and p.R165W presented the disease later. Regarding the MMAuria patients, we have found three novel mutations in the MUT gene (c.1068G>A, c.1587_1594del8 and c.593delA) and one in the MMAB gene (c.349-1 G>C). Two patients with MMAuria with homocystinuria cblC type are carriers of the frequent c.271dupA mutation. All mut(0), cblB and cblC patients presented the symptoms early and in general had more neurological complications, while cblA and mut(-) patients exhibited a late-onset presentation, and in general the long-term outcome was better. The results presented in this work emphasize the importance of the genetic analysis of the patients not only for diagnostic purposes but also to research into novel therapies based on the genotype.

9 páginas, 4 figuras, 5 esquemas., A convergent and high-yielding approach for the asymmetric synthesis of sulforaphane 2 and four analogues differently substituted at the sulfinyl sulfur has been developed. The key step of the synthesis is the diastereoselective synthesis of sulfinate ester 23-S(S), using the DAG (diacetone-D-glucofuranose)-methodology. The biological activity of these compounds as inductors of phase II detoxifying enzyme has been studied by determining their ability to activate the cytoprotective transcription factor Nrf2., Financial support from the DGICyT (grant nos. CTQ2006-15515-CO2-01 and CTQ2007-61185) and the Junta de Andalucía (grants P06-FQM-01852 and P07-FQM-2774) is gratefully acknowledged. A.A. thanks the Ministerio de Ciencia e Innovación for a Ramón y Cajal contract. F.L. is supported by a predoctoral fellowship of the “Studienstiftung des Deutschen Volkes”.

The stereochemical outcome of the reaction of chiral secondary alcohols with a phosphinyl chloride was found to be highly dependent on the achiral base used. Thus, the reaction of the readily available sugar derived carbinols, 1 and 2 , with methylphenylphosphinyl chloride in the presence of triethylamine yields stereoselectively the corresponding S np-phosphinates 3 S p and 5 S p in 94 and 92% diastereomeric excess (de). Simply changing the base from triethylamine to pyridine affords R p-phosphinates 4 R p and 6 R p epimers to 3 S p and 5 S p at the phosphinyl phosphorus in 50 and 40% de respectively. These phosphinate esters were found to be good P-chiral transferring intermediates, they react with Grignard reagents under very mild conditions to give the corresponding phosphine oxides. Both enantiomers S p- and R p- o -anisylmethylphenylphosphine oxide (PAMPO) as well S p- and R p- methylphenylpropyl phosphine oxide were obained enantiomerically pure in high yields

The Diels–Alder reaction of enantiomerically pure (E)-γ-keto-α,β-unsaturated p-tolylsulphoxides 3 with cyclopentadiene give four easily separable diastereomers. The effect of several Lewis acids on the reaction was studied, finding a high endo selectivity with respect to the carbonyl group and moderate π-diastereoselectivity using BF3·Et2O as catalyst. The reactivity of compounds 3 as well as their endo selectivity are both higher than those observed for the corresponding (E)-3-sulfinylacrylates.

The stereochemical outcome of the reaction of chiral secondary alcohols with a phosphinyl chloride was found to be highly dependent on the achiral base used. Thus, the reaction of the readily available sugar derived carbinols, 1 and 2 , with methylphenylphosphinyl chloride in the presence of triethylamine yields stereoselectively the corresponding S np-phosphinates 3 S p and 5 S p in 94 and 92% diastereomeric excess (de). Simply changing the base from triethylamine to pyridine affords R p-phosphinates 4 R p and 6 R p epimers to 3 S p and 5 S p at the phosphinyl phosphorus in 50 and 40% de respectively. These phosphinate esters were found to be good P-chiral transferring intermediates, they react with Grignard reagents under very mild conditions to give the corresponding phosphine oxides. Both enantiomers S p- and R p- o -anisylmethylphenylphosphine oxide (PAMPO) as well S p- and R p- methylphenylpropyl phosphine oxide were obained enantiomerically pure in high yields

An efficient and general oxidative demetalation of (eta(3)-allyl)molybdenum complexes using pyridinium dichromate allows the introduction of a carbonyl group at an allylic terminus of the pi-system. The process takes place with high regiocontrol and can lead to the preparation of unsaturated ketones and lactones of high enantiopurity.

Chlorambucilamide derivatives involving chiral glycosyl glycerols derived from D-glucosamine were synthesized in good yield by coupling the chlorambucil moiety to the amino group of ω-amino-(ω-1)-hydroxyalkyl 2-acylamino-4,6-O-benzylidene-2-deoxy-β-D-glucopyranosides, and subsequent hydrolysis of the benzylidene group. The starting material was easily available from 2-acetamido-2-deoxy-D-glucose. The bonding of 2,3,4,6-tetra-O-pivaloyl-β-D-galactopyranosylamine to chlorambucil by formation of an amide function is also described. Chirality Chirality 14:199–203, 2002. © 2002 Wiley-Liss, Inc.