"Geographical distribution of risk genotypes in pediatric patients with celiac disease in Spain".

Celiac disease is strongly associated with HLA DQ, specifically with haplotypes. DRB1*03-DQA1*05:01/DQB1*02:01 (DQ2.5),DRB1*07-DQA1*02:01/DQB1*02:02 (DQ2.

Thermal and Photocatalytic Performance of Unsaturated Polyester Resins Modified with TiO Nanoparticles as Panel Bodies for Vehicles.

The transport sector is the fastest growing contributor to climate emissions and experiences the highest growth in energy use. This study explores the use of TiO nanoparticles for obtaining photocatalytic nanocomposites with improved infrared reflectance properties. The nanocomposites were prepared by dispersing 0-20 wt% of TiO nanoparticles in an unsaturated polyester resin.

A noninvasive postoperative clinical score to identify patients at risk for postoperative pulmonary complications: the Air-Test Score.

Background: Postoperative pulmonary complications (PPCs) negatively affect morbidity, healthcare costs and postsurgical survival. Preoperative and intraoperative peripheral oxyhemoglobin saturation (SpO2) levels are independent risk factors for postoperative pulmonary complications (PPCs). The air-test assesses the value of SpO2 while breathing room-air.

Effects of oxygen on post-surgical infections during an individualised perioperative open-lung ventilatory strategy: a randomised controlled trial.

Background: We aimed to examine whether using a high fraction of inspired oxygen (FIO) in the context of an individualised intra- and postoperative open-lung ventilation approach could decrease surgical site infection (SSI) in patients scheduled for abdominal surgery.

Methods: We performed a multicentre, randomised controlled clinical trial in a network of 21 university hospitals from June 6, 2017 to July 19, 2018. Patients undergoing abdominal surgery were randomly assigned to receive a high (0.

Optimization of the Synthesis of Glycerol Derived Monoethers from Glycidol by Means of Heterogeneous Acid Catalysis.

We present an efficient and green methodology for the synthesis of glycerol monoethers, starting from glycidol and different alcohols, by means of heterogeneous acid catalysis. A scope of Brønsted and Lewis acid catalysts were applied to the benchmark reaction of glycidol and methanol. The selected catalysts were cationic exchangers, such as Nafion NR50, Dowex 50WX2, Amberlyst 15 and K10-Montmorillonite, both in their protonic form and exchanged with Al(III), Zn(II) and Fe(III).

Individualised perioperative open-lung approach versus standard protective ventilation in abdominal surgery (iPROVE): a randomised controlled trial.

Background: The effects of individualised perioperative lung-protective ventilation (based on the open-lung approach [OLA]) on postoperative complications is unknown. We aimed to investigate the effects of intraoperative and postoperative ventilatory management in patients scheduled for abdominal surgery, compared with standard protective ventilation.

Methods: We did this prospective, multicentre, randomised controlled trial in 21 teaching hospitals in Spain.

Glycerol as a source of designer solvents: physicochemical properties of low melting mixtures containing glycerol ethers and ammonium salts.

In this work we report the preparation of mixtures of several alkyl glyceryl ethers, as hydrogen bond donor compounds, with two ammonium salts, choline chloride and N,N,N-triethyl-2,3-dihydroxypropan-1-aminium chloride. The stability of the mixtures at different molar ratios and temperatures has been evaluated in order to determine the formation of low melting mixtures. Liquid and stable mixtures have been characterized and their physico-chemical properties such as density, viscosity, refractive index, conductivity and surface tension have been measured in the temperature range of 293.

Ecotoxicity and QSAR studies of glycerol ethers in Daphnia magna.

Glycerol is currently considered a raw, renewable material, which can be used to synthesize new glycerol derivatives that may be used as green solvents. However, these compounds must be environmentally evaluated before their use. The acute ecotoxicity of a series of mono-, di-, and trialkyl ethers synthesized from glycerol for the crustacean Daphnia magna has been studied.

Comparative ecotoxicology study of two neoteric solvents: Imidazolium ionic liquid vs. glycerol derivative.

In this study we have compared the acute ecotoxicity of two solvents, with very different structure and origin, but sharing many physical-chemical properties, so they can be used for similar purposes; a well-known ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF6]) and a solvent partially derived from biomass, 3-bis(2,2,2-trifluoroethoxy)propan-2-ol (BTFIP). We have used three biomodels (Vibrio fischeri, Daphnia magna and Danio rerio) and performed the comparison applying the Environmental, Health and Safety (EHS) hazard assessment. According to the results, ecotoxicity of [BMIM][PF6] and BTFIP is quite similar in the simplest model Vibrio fischeri, while in Daphnia magna [BMIM][PF6] is clearly more toxic.

Influence of Polarity and Activation Energy in Microwave-Assisted Organic Synthesis (MAOS).

The aim of this work was to determine the parameters that have decisive roles in microwave-assisted reactions and to develop a model, using computational chemistry, to predict a priori the type of reactions that can be improved under microwaves. For this purpose, a computational study was carried out on a variety of reactions, which have been reported to be improved under microwave irradiation. This comprises six types of reactions.

Polytopic bis(oxazoline)-based ligands for recoverable catalytic systems applied to the enantioselective Henry reaction.

Several kinds of polytopic chiral ligands (including ditopic, tritopic and tetratopic), based on the bis(oxazoline) and azabis(oxazoline) motifs, have been tested in the preparation of recoverable catalytic systems for the Henry reaction. The results obtained with the different ligands are, in general, good, but they point to the existence of a delicate balance between the coordinating ability of the ligand, the catalytic activity and the recovery of the catalyst by formation of the coordination polymer, related to the easiness to form oligomeric species in solution.

Predicting the enantioselectivity of the copper-catalysed cyclopropanation of alkenes by using quantitative quadrant-diagram representations of the catalysts.

We present a new methodology to predict the enantioselectivity of asymmetric catalysis based on quantitative quadrant-diagram representations of the catalysts and quantitative structure-selectivity relationship (QSSR) modelling. To account for quadrant occupation, we used two types of molecular steric descriptors: the Taft-Charton steric parameter (ν(Charton)) and the distance-weighted volume (V(W) ). By assigning the value of the steric descriptors to each of the positions of the quadrant diagram, we generated the independent variables to build the multidimensional QSSR models.

Bis(oxazoline)-based coordination polymers: a recoverable system for enantioselective Henry reactions.

An efficient release-capture strategy for the recovery and reuse of enantioselective catalysts in the Henry reaction is described. This strategy is based on the precipitation of an insoluble coordination polymer at the end of each reaction, allowing easy separation from products. The coordination polymer is formed through aggregation of Cu(II) ions with ditopic bisoxazoline-based chiral ligands.

Multiphase enantioselective Kharasch-Sosnovsky allylic oxidation based on neoteric solvents and copper complexes of ditopic ligands.

Recoverable multiphase enantioselective catalytic systems for the Kharasch-Sosnovsky oxidation of cycloalkenes with tert-butyl peroxybenzoate are described, based on the use of [BMIM][PF(6)] and a new solvent derived from glycerol as the catalyst reservoir phases, and chiral copper complexes with different ligands from the bis(oxazoline) family. The best results are obtained with the glycerol-derived solvent and a recently described azabisoxazoline-based ditopic ligand, allowing up to four uses of the catalytic phase with good results.

DFT studies on cobalt-catalyzed cyclotrimerization reactions: the mechanism and origin of reaction improvement under microwave irradiation.

A DFT computational mechanistic study of the [2+2+2] cyclotrimerization of a diyne with benzonitrile, catalyzed by a cobalt complex, has been carried out. Three alternative catalytic cycles have been examined together with the precatalytic step (responsible for the induction period). The favored mechanism takes place by means of an intramolecular metal-assisted [4+2] cycloaddition.

Accurate calculation of chemical shifts in highly dynamic H2@C60 through an integrated quantum mechanics/molecular dynamics scheme.

A new protocol combining classical MD simulations and DFT calculations is presented to accurately estimate the (1)H NMR chemical shifts of highly mobile guest-host systems and their thermal dependence. This strategy has been successfully applied for the hydrogen molecule trapped into C(60) fullerene, an unresolved and challenging prototypical case for which experimental values have never been reproduced. The dependence of the final values on the theoretical method and their implications to avoid over interpretation of the obtained results are carefully described.

Can enantioselectivity be computed in enthalpic barrierless reactions? The case of Cu(I)-catalyzed cyclopropanation of alkenes.

An extensive computational study has been carried out on different catalytic systems for cyclopropanation reactions based on copper. Most DFT schemes used present drawbacks that preclude the calculation of accurate absolute kinetic properties (energy barriers) of such systems, excepting the M05 and M06 suites of density functionals. On the other hand, there is a wide range of DFT methods capable of reproducing relative energy values, which can be easily translated into selectivities.

Applied biotransformations in green solvents.

The definite interest in implementing sustainable industrial technologies has impelled the use of biocatalysts (enzymes or cells), leading to high chemo-, regio- and stereoselectivities under mild conditions. As usual substrates are not soluble in water, the employ of organic solvents is mandatory. We will focus on different attempts to combine the valuable properties of green solvents with the advantages of using biocatalysts for developing cleaner synthetic processes.

Stereoselectivity induced by support confinement effects. Aza-pyridinoxazolines: A new family of C(1)-symmetric ligands for copper-catalyzed enantioselective cyclopropanation reactions.

Aza-pyridinoxazoline ligands, a new class of C(1)-symmetric ligands, are described and tested in the heterogeneous enantioselective catalysis of a cyclopropanation reaction, with the aim of improving surface confinement effects by the clay support on the reaction stereoselectivity. In the case of trans/cis diastereoselectivity, these surface effects lead to a systematic reversal of selectivity, cis-cyclopropanes being favored. Regarding the enantioselectivities, support confinement has a positive effect in the case of major cis-cyclopropane products, leading to moderate enantioselectivity values (60% ee).

Enantioselective catalysis with chiral complexes immobilized on nanostructured supports.

In this tutorial review, we discuss how recycling and stability advantages alone are frequently not sufficient to justify the effort necessary to immobilize chiral complexes unless additional advantages are found. Nanostructured solids with well-controlled surfaces and pores may act as nanoreactors, hindering or even blocking some of the reaction channels, and hence modifying the stereochemical result of the reaction. The use of support effects to improve or change the enantioselectivity is emerging as an interesting field, whose understanding might allow, in the near future, the design of chiral ligands better adapted to this strategy.

Linking homogeneous and heterogeneous enantioselective catalysis through a self-assembled coordination polymer.

Combining the advantages of homogeneous and heterogeneous enantioselective catalysis is possible through self-supported copper coordination polymers, based on a new kind of ditopic chiral ligand bearing two azabis(oxazoline) moieties. When the coordination polymer is used to catalyze a cyclopropanation reaction, it becomes soluble in reaction conditions but precipitates after reaction completion, allowing easy recovery and efficient reuse in the same reaction up to 14 times.

An efficient and straightforward access to sulfur substituted [2.2]paracyclophanes: application to stereoselective sulfenate salt alkylation.

A straightforward and high-yielding access to various [2.2]paracyclophanes possessing a sulfur-based functional group is reported, the key step being a SEAr reaction mediated by a sulfonium salt. The versatility of the methodology was exemplified by an original application in sulfenate salt chemistry, from which a remarkable chirality transfer was observed.

C1-symmetric versus C2-symmetric ligands in enantioselective copper-bis(oxazoline)-catalyzed cyclopropanation reactions.

A thorough experimental and theoretical study of the enantioselective cyclopropanation of alkenes catalyzed by chiral bis(oxazoline)- and azabis(oxazoline)-copper complexes, which comprise a new family of ligands that lack C2 symmetry, has been conducted. Surprisingly high enantioselectivities were observed with some of these ligands, which were rationalized on the basis of molecular modeling studies. The course of the asymmetric induction in connection with ligand symmetry and the implications for supported enantioselective catalysts are discussed.