bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of transcatheter and surgical treatment of paravalvular leak: Results from a 5‐year follow‐up study
Authors: Zhang Youjun , Pan Xin , Qu Xinkai , Wang Cheng , Huang Estella , Ma Lan , Wu Weihua , Fang Weiyi
Published: October 2017

Objective

This study aimed to compare the efficacy and safety of two different treatments of paravalvular leak (PVL).

Background

PVL is a common complication after surgical valve replacement. Re‐operation is associated with high mortality, morbidity, and risk of re‐leak. Catheter‐based repair has emerged as a promising new therapy.

Methods and Results

Eighty‐seven consecutive patients with symptomatic PVL received either transcatheter (n = 46) or surgical (n = 41) treatment at Shanghai Chest Hospital between January 2009 and December 2015.The procedural and clinical success rates were similar between the transcatheter group and the surgical group (82.6 vs. 90.2%; P = 0.30; and 69.5 vs. 73.0%; P = 0.71, respectively). There were fewer in‐hospital total major adverse events in the transcatheter group (56.09 vs. 17.39%; P < 0.001), and transcatheter repair was more cost‐effective, with fewer blood transfusions, shorter procedure durations, shorter hospital stays, and less expenditure. However, there were six cases of hemolysis aggravation in the transcatheter group (13.04%). The 5‐year overall survival rates after transcatheter and surgical repair were 74.39 and 71.95% (P = 0.45), respectively, and the cardiac‐related survival rates were 84.08 and 74.72% (P = 0.19), respectively.

Conclusion

Transcatheter and surgical repairs are both effective treatments for selected patients with PVL. And, transcatheter closure seems to be safer and more cost‐effective. Nonetheless, this new treatment may be risky for post‐procedure hemolysis when unsuitable devices are used.
Predictors of in‐hospital effectiveness and complications of rotational atherectomy (from the ORPKI Polish National Registry 2014–2016)
Authors: Januszek Rafał , Siudak Zbigniew , Dziewierz Artur , Dudek Dariusz , Bartuś Stanisław
Published: October 2017

Objective

The aim of the study was to assess trends in the use and periprocedural outcomes of rotational atherectomy (RA) in Poland between January 2014 and December 2016.

Background

In recent years, due to the aging population, RA is becoming more commonly used to treat heavily calcified coronary artery stenoses.

Methods

Data were prospectively collected using the Polish Cardiovascular Intervention Society national registry on all percutaneous coronary intervention (PCI) procedures performed in Poland. In total, 1,175 RA procedures were recorded from 317,175 PCI procedures (incidence of 0.37%).

Results

Patients undergoing RA were older (71.7 ± 9.7 vs. 66.9 ± 10.8, P < 0.00001) and less often males (68.3% vs. 76.4%, P < 0.00001). The complication rate was significantly higher in the RA group (P = 0.0012) with the leading coronary artery perforation (CAP) (P < 0.0001). Complication frequency decreased significantly in the last 3 years and was accompanied by an increase in the percentage of radial access and patients with stable angina. Among several predictors of the use of RA during PCI in multivariate analysis, the strongest one was previous coronary artery by‐pass grafting (P < 0.0001), whereas the strongest, predictor of CAP was the RA procedure (P = 0.00004). The increase in RA frequency over the last 3 years may reflect population aging, some fluctuations in indications for RA and reimbursement policies.

Conclusions

We observed a substantial increase in the utilization of RA during PCIs performed in Poland; however, it still needs to be increased. Decreased frequency of RA procedures follows change in indications for RA and vascular access. Periprocedural complication rates significantly decreased over the last 3 years.
Percutaneous axillary arteriotomy closure during transcatheter aortic valve replacement using the MANTA device
Authors: De Palma Rodney , Rück Andreas , Settergren Magnus , Saleh Nawzad
Published: October 2017

Percutaneous aortic valve replacement is performed predominantly via the transfemoral approach. The transaxillary (subclavian) approach may be utilized if an alternative route access is required. Conventional access and closure for this approach necessitates open surgical techniques. We report a nonsurgical fully percutaneous axillary TAVR using a collagen‐based vascular closure device.
One‐year clinical and computed tomography follow‐up after implantation of bioresorbable vascular scaffolds in patients with coronary chronic total occlusions
Authors: Maeremans Joren , Verhaert David , Pereira Bruno , Frambach Peter , Van Mieghem Carlos , Barbato Emanuele , Willems Endry , Vrolix Mathias , Dens Jo
Published: October 2017

Objectives

To assess the safety and efficacy of everolimus‐eluting bioresorbable scaffolds (BRS) in the treatment of chronic total occlusions (CTO) using noninvasive multislice computed tomography (MSCT) angiography at one‐year follow‐up.

Background

Current evidence regarding the safety and efficacy of BRS for the percutaneous treatment of CTO is limited.

Methods

Between September 2013 and January 2016, patients who received one or more ABSORB BRSs were included at three centers. MSCT (including quantitative analysis) and clinical follow‐up were performed at one year.

Results

Forty‐one CTO patients were included. Mean age was 60 ± 11 years and the majority was male (83%). Average Japanese CTO (J‐CTO) score was 0.9 ± 0.9. Seventy‐one BRS were implanted in total with, on average, 1.7 ± 0.8 scaffolds/patient, and a total length of 43 ± 20 mm and diameter of 3.1 ± 0.4 mm. One noncardiac death took place. MSCT angiography was performed in 34 (83%) patients: all scaffolds were patent, except in one patient, in whom a patent target vessel was present on subsequent diagnostic angiography. MSCT quality was sufficient for quantitative analyses in 27 patients (46 scaffolds): median reference versus scaffold minimal lumen diameter and minimal lumen area were measured, and showed a small difference of 0.1 mm (−0.2–0.4) (lumen diameter stenosis = 3.0%) and 0.5 mm2 (−1.0–2.0) (lumen area stenosis = 4.2%).

Conclusions

The low number of events and high patency rate at 1 year are encouraging the further use of the ABSORB scaffold for CTOs with low J‐CTO score. Noninvasive MSCT angiography is a valid tool to assess scaffold patency, although its image resolution limits the use for quantitative measurements.
Structure Sensitivity of Acrolein Hydrogenation by Platinum Nanoparticles on BaxSr1−xTiO3Nanocuboids
Authors: Engelhardt Christopher M. , Kennedy Robert M. , Enterkin James A. , Poeppelmeier Kenneth R. , Ellis Donald E. , Marshall Christopher L. , Stair Peter C.
Published: October 2017

The structure sensitivity of Pt nanoparticles (PtN) for gas‐phase acrolein (AC) hydrogenation was probed for PtNon BaxSr1−xTiO3nanocuboid supports with (0 0 1) facets in a combined theoretical and experimental study. The in situ selectivity for allyl alcohol increased with the increase of the Sr concentration in the support, which corresponds to modifications in the stable Winterbottom shape and lattice strain of the Pt nanoparticles as a result of the interfacial energy between Pt and the BaxSr1−xTiO3supports. “Local model” nanofacets of the Pt surface, edge, and corner morphologies were developed as compact representations of adsorption and reaction sites. DFT was used as the primary modeling tool for the equilibrium adsorption states. We argue that adsorption on edge sites is critically important for the overall allyl alcohol selectivity of PtNcatalysts. A simple model was developed to represent PtNstrain effects caused by its interaction with the substrate. Bader topological atom, spherical volume averaging charge, and modified bond valence sum analyses were used to understand the bonding structure. Density of states analysis was performed for the structures of PtN, adsorbed AC, and intermediate products to examine adsorbate–particle interactions. The simulated hydrogenation of AC on PtNnanofacets was compared to the in situ hydrogenation of AC by PtNon BaxSr1−xTiO3to examine the effects of facet, edge, and corner sites on the overall selectivity.
Selective Catalytic Oxidation of Cyclohexene with Molecular Oxygen: Radical Versus Nonradical Pathways
Authors: Denekamp Ilse M. , Antens Martijn , Slot Thierry K. , Rothenberg Gadi
Published: October 2017

We study the allylic oxidation of cyclohexene with O2 under mild conditions in the presence of transition‐metal catalysts. The catalysts comprise nanometric metal oxide particles supported on porous N‐doped carbons (M/N:C, M=V, Cr, Fe, Co, Ni, Cu, Nb, Mo, W). Most of these metal oxides give only moderate conversions, and the majority of the products are over‐oxidation products. Co/N:C and Cu/N:C, however, give 70–80 % conversion and 40–50 % selectivity to the ketone product, cyclohexene‐2‐one. Control experiments in which we used free‐radical scavengers show that the oxidation follows the expected free‐radical pathway in almost all cases. Surprisingly, the catalytic cycle in the presence of Cu/N:C does not involve free‐radical species in solution. Optimisation of this catalyst gives >85 % conversion with >60 % selectivity to the allylic ketone at 70 °C and 10 bar O2. We used SEM, X‐ray photoelectron spectroscopy and XRD to show that the active particles have a cupric oxide/cuprous oxide core–shell structure, giving a high turnover frequency of approximately 1500 h−1. We attribute the high performance of this Cu/N:C catalyst to a facile surface reaction between adsorbed cyclohexenyl hydroperoxide molecules and activated oxygen species.
Performance of Nanofiltration‐Like Forward‐Osmosis Membranes for Aerobically Treated Palm Oil Mill Effluent
Authors: Abdullah Wan Nur Ain Shuhada , Lau Woei-Jye , Aziz Farhana , Emadzadeh Daryoush , Ismail Ahmad Fauzi
Published: October 2017

For the first time, engineered osmosis was performed using commercial nanofiltration (NF) membranes for the treatment process of aerobically treated palm oil mill effluent (AT‐POME). Compared to conventional forward‐osmosis (FO) membranes with dense rejection layer, the NF‐like FO membranes offer a higher water flux with minimum reverse solute flux provided appropriate solutes like divalent salts or polyelectrolytes were used in the draw solution. Both NF membranes were able to treat the AT‐POME by completely preventing the color component from passing through the permeate side under FO and pressure‐retarded osmosis (PRO) orientation. The water fluxes of the membranes were higher under PRO orientation owing to the reduced internal concentration polarization effect. Relatively loose membranes for the engineered osmosis application could address severe surface fouling of membranes tested under pressure‐driven filtration.
Editorial
Authors: Lange Rüdiger , Bauer Tobias
Published: October 2017

No abstract.
Chiral Discrimination through 1H NMR and Luminescence Spectroscopy: Dynamic Processes and Solid Strip for Chiral Recognition
Authors: Gangopadhyay Monalisa , Maity Arunava , Dey Ananta , Rajamohanan P. R. , Ravindranathan Sapna , Das Amitava
Published: October 2017

The appropriate choice of the host molecules with well‐defined optical activity (S‐H/R‐H) helps in the differentiation between two secondary ammonium ion‐derivative guest molecules with different optical activities (R‐G/S‐G) based on the fluorescence resonance energy transfer (FRET)‐based luminescence responses. Crown ether‐based host molecules with opposite chiral configurations (R‐H, S‐H) have been derived from 1,1′‐bi‐2‐naphthol (BINOL) derivatives that have axially chiral biaryl centers. These chiral crown ethers form host–guest complexes (i.e., [2]pseudorotaxanes) with chiral secondary ammonium ion derivatives (R‐G, S‐G). NMR spectroscopic studies show that the complexes are in a dynamic equilibrium in solution. Results of the 1H NMR and fluorescence spectroscopic studies indicate a head‐on orientation of the host and guest in the [2]pseudorotaxanes. The difference in the efficiency in the FRET‐based responses between anthracene and the BINOL derivatives allow efficient chiral discrimination of the guests. Isothermal titration calorimetry and NMR investigations reveal that inclusion complexes between hosts and guests of the same chirality (R‐H⋅R‐G, S‐H⋅S‐G) are more stable relative to those of opposite chirality (R‐H⋅S‐G, S‐H⋅R‐G). However, FRET‐based energy‐transfer efficiency is higher for R‐H⋅S‐G and S‐H⋅R‐G complexes. NMR spectroscopic studies show that the relative orientation of the guest in the host cavity is significantly different when the host binds a guest of the same or opposite chirality; furthermore, the latter is more favorable for FRET, thus enabling discrimination between enantiomers. Interestingly, chiral discrimination of guest ions could also be achieved by using silica surfaces modified with chiral host molecules.
Surface‐Enhanced Raman Spectroscopy Characterization of Salt‐Induced Aggregation of Gold Nanoparticles
Authors: Chan Matthew Y. , Leng Weinan , Vikesland Peter J.
Published: October 2017

Low‐frequency (<300 cm−1) vibrational interactions between gold surfaces and dissolved halides in water were investigated by surface‐enhanced Raman spectroscopy (SERS). Experiments with NaF, NaCl, NaBr, and NaI salts indicate that the Raman shifts of the Au‐X− SERS bands correlate with the bond strength of the corresponding covalent interaction. These low‐frequency SERS bands open up new means to investigate the aggregation of nanoparticles in aqueous environments.
Role of the Chalcogen (S, Se, Te) in the Oxidation Mechanism of the Glutathione Peroxidase Active Site
Authors: Bortoli Marco , Torsello Mauro , Bickelhaupt F. Matthias , Orian Laura
Published: October 2017

The front cover artwork is provided by the groups of Prof. Dr. F. Matthias Bickelhaupt (VU Amsterdam, The Netherlands) and Prof. Dr. Laura Orian (Università degli Studi di Padova, Italy). The GPx active sites resemble lightning bolts during a thunderstorm (S and Te mutants), and during a clear night for Sec‐GPx, associating its much higher anti‐oxidant power to the tremendously powerful positive lightning bolts. Read the full text of the article at 10.1002/cphc.201700743.
Improved Free‐Energy Landscape Quantification Illustrated with a Computationally Designed Protein–Ligand Interaction
Authors: Van Patten William J. , Walder Robert , Adhikari Ayush , Okoniewski Stephen R. , Ravichandran Rashmi , Tinberg Christine E. , Baker David , Perkins Thomas T.
Published: October 2017

Quantifying the energy landscape underlying protein–ligand interactions leads to an enhanced understanding of molecular recognition. A powerful yet accessible single‐molecule technique is atomic force microscopy (AFM)‐based force spectroscopy, which generally yields the zero‐force dissociation rate constant (koff) and the distance to the transition state (Δx≠). Here, we introduce an enhanced AFM assay and apply it to probe the computationally designed protein DIG10.3 binding to its target ligand, digoxigenin. Enhanced data quality enabled an analysis that yielded the height of the transition state (ΔG≠=6.3±0.2 kcal mol−1) and the shape of the energy barrier at the transition state (linear‐cubic) in addition to the traditional parameters [koff (=4±0.1×10−4 s−1) and Δx≠ (=8.3±0.1 Å)]. We expect this automated and relatively rapid assay to provide a more complete energy landscape description of protein–ligand interactions and, more broadly, the diverse systems studied by AFM‐based force spectroscopy.
How beta diversity and the underlying causes vary with sampling scales in the Changbai mountain forests
Authors: Tan Lingzhao , Fan Chunyu , Zhang Chunyu , von Gadow Klaus , Fan Xiuhua
Published: October 2017

This study aims to establish a relationship between the sampling scale and tree species beta diversity temperate forests and to identify the underlying causes of beta diversity at different sampling scales. The data were obtained from three large observational study areas in the Changbai mountain region in northeastern China. All trees with a dbh ≥1 cm were stem‐mapped and measured. The beta diversity was calculated for four different grain sizes, and the associated variances were partitioned into components explained by environmental and spatial variables to determine the contributions of environmental filtering and dispersal limitation to beta diversity. The results showed that both beta diversity and the causes of beta diversity were dependent on the sampling scale. Beta diversity decreased with increasing scales. The best‐explained beta diversity variation was up to about 60% which was discovered in the secondary conifer and broad‐leaved mixed forest (CBF) study area at the 40 × 40 m scale. The variation partitioning result indicated that environmental filtering showed greater effects at bigger grain sizes, while dispersal limitation was found to be more important at smaller grain sizes. What is more, the result showed an increasing explanatory ability of environmental effects with increasing sampling grains but no clearly trend of spatial effects. The study emphasized that the underlying causes of beta diversity variation may be quite different within the same region depending on varying sampling scales. Therefore, scale effects should be taken into account in future studies on beta diversity, which is critical in identifying different relative importance of spatial and environmental drivers on species composition variation.
Receptor uptake arrays for vitamin B12, siderophores, and glycans shape bacterial communities
Authors: Frank Steven A.
Published: October 2017

Molecular variants of vitamin B12, siderophores, and glycans occur. To take up variant forms, bacteria may express an array of receptors. The gut microbeBacteroides thetaiotaomicronhas three different receptors to take up variants of vitamin B12and 88 receptors to take up various glycans. The design of receptor arrays reflects key processes that shape cellular evolution. Competition may focus each species on a subset of the available nutrient diversity. Some gut bacteria can take up only a narrow range of carbohydrates, whereas species such asB. thetaiotaomicroncan digest many different complex glycans. Comparison of different nutrients, habitats, and genomes provides opportunity to test hypotheses about the breadth of receptor arrays. Another important process concerns fluctuations in nutrient availability. Such fluctuations enhance the value of cellular sensors, which gain information about environmental availability and adjust receptor deployment. Bacteria often adjust receptor expression in response to fluctuations of particular carbohydrate food sources. Some species may adjust expression of uptake receptors for specific siderophores. How do cells use sensor information to control the response to fluctuations? This question about regulatory wiring relates to problems that arise in control theory and artificial intelligence. Control theory clarifies how to analyze environmental fluctuations in relation to the design of sensors and response systems. Recent advances in deep learning studies of artificial intelligence focus on the architecture of regulatory wiring and the ways in which complex control networks represent and classify environmental states. I emphasize the similar design problems that arise in cellular evolution, control theory, and artificial intelligence. I connect those broad conceptual aspects to many testable hypotheses for bacterial uptake of vitamin B12, siderophores, and glycans.
Energy and speleogenesis: Key determinants of terrestrial species richness in caves
Authors: Jiménez‐Valverde Alberto , Sendra Alberto , Garay Policarp , Reboleira Ana Sofia P. S.
Published: October 2017

The aim of this study was to unravel the relative role played by speleogenesis (i.e., the process in which a cave is formed), landscape‐scale variables, and geophysical factors in the determination of species richness in caves. Biological inventories from 21 caves located in the southeastern Iberian Peninsula along with partial least square (PLS) regression analysis were used to assess the relative importance of the different explanatory variables. The caves were grouped according to the similarity in their species composition; the effect that spatial distance could have on similarity was also studied using correlation between matrices. The energy and speleogenesis of caves accounted for 44.3% of the variation in species richness. The trophic level of each cave was the most significant factor in PLS regression analysis, and epigenic caves (i.e., those formed by the action of percolating water) had significantly more species than hypogenic ones (i.e., those formed by the action of upward flows in confined aquifers). Dissimilarity among the caves was very high (multiple‐site βsim = 0.92). Two main groups of caves were revealed through the cluster analysis, one formed by the western caves and the other by the eastern ones. The significant—but low—correlation found between faunistic dissimilarity and geographical distance (r = .16) disappeared once the caves were split into the two groups. The extreme beta‐diversity suggests a very low connection among the caves and/or a very low dispersal capacity of the species. In the region under study, two main factors are intimately related to the richness of terrestrial subterranean species in caves: the amount of organic material (trophic level) and the formation process (genesis). This is the first time that the history of a cave genesis has been quantitatively considered to assess its importance in explaining richness patterns in comparison with other factors more widely recognized.
Synthesis and Isotope Effects on the Excited State Properties of N^N Bound [Ir(polypyridyl)2Cl2]PF6 Complexes
Authors: Soman Suraj , Younis Hamid M. , Browne Wesley R. , Vos Johannes G. , Pryce Mary T.
Published: October 2017

A versatile approach to the preparation of [Ir(LL)2Cl2](PF6) type complexes is reported, in which LL is an N^N bound polypyridyl ligand [X2bpy, X2phen, where X = H‐, CH3‐, (CH3)3C‐, or phenyl‐, and bpy = 2,2′‐bipyridyl, phen = 1,10‐phenanthroline] as well as their deuterated analogues. In the synthesis of [Ir(bpy)2Cl2]PF6 (I) and its deuterated analogue (III), the cyclometallated complexes [Ir(bpy)2(bpy‐C–N)](PF6)2 (II) and [Ir([D8]‐bpy)2([D8]‐bpy‐C–N)](PF6)2 (IV) were also obtained. The complexes are characterised by 1H NMR, UV/Vis absorption and emission spectroscopy. The effect of deuteration on emission quantum yields and emission lifetimes is discussed. The ready availability of these complexes through efficient scaleable synthetics routes opens new opportunities for their use, especially in energy related applications.
Large‐Scale Synthesis of Symmetric Tetramine Ligands by Using a Modular Double Reductive Amination Approach
Authors: Tretbar Maik , Stark Christian B. W.
Published: October 2017

Tetramine ligands play an important role in a broad range of transition metal catalyzed transformations. We here present a flexible and modular approach to this class of ligands using a double reductive amination strategy. Thus, the target molecules were prepared in a highly efficient manner in only three steps, from commercially available starting materials. Excellent overall yields, of up to 96 % were reached. Notably, chiral C2‐symmetric ligands are available using this procedure. All reactions are easily scalable and the tetramine ligands were obtained in excellent purity, while only a single chromatographic purification is required at the end of the three step sequence.
Triazacoronene Derivatives with Three peri‐Benzopyrano Extensions: Synthesis, Structure, and Properties
Authors: Liu Bo , Shi Donghui , Yang Yihui , Liu Dayong , Li Ming , Liu Ernu , Wang Xiaogang , Zhang Qiang , Yang Mingyu , Li Jing , Shi Xianying , Wang Wenliang , Wei Junfa
Published: October 2017

New π‐extended triazacoronene derivatives containing three peri‐benzopyrano extensions were successfully synthesized through tandem triflic acid catalyzed threefold Pictet–Spengler cyclization and K2CO3‐catalyzed ipso‐aromatic substitution in one pot. The structure was verified by X‐ray diffraction analysis and was found to form a sandwich‐type π trimer in the crystalline state. The π‐extended triazacoronenes showed reasonable solubility, high thermal stability, and remarkably repeatable electroluminescent emissions.
Stereoselective Intramolecular Dearomatizative [4+2] Cycloaddition of Linked Ethynylnaphthol–Benzofuran Systems
Authors: Beppu Shota , Arae Sachie , Furusawa Masaki , Arita Kosuke , Fujimoto Hitoshi , Sumimoto Michinori , Imahori Tatsushi , Igawa Kazunobu , Tomooka Katsuhiko , Irie Ryo
Published: October 2017

A base‐catalyzed stereoselective intramolecular dearomatizative [4+2] cycloaddition of o‐phenylene‐linked ethynylnaphthol–benzofuran systems was explored. In this reaction, we presume the involvement of electrophilic vinylidene o‐quinone methides (4π), which add across the electron‐rich furan double bonds (2π) to produce elaborate, fused oxa‐polyheterocyclic frameworks with consecutive quaternary and tertiary asymmetric carbon atoms as single diastereomers. The catalytic and enantioselective synthesis of these chiral fused polyheterocyclic structures is also feasible with the use of a prevalent cinchonidine or cinchonine chiral base.
Improvement of anaerobic digestion of landfill leachate by using coagulation‐flocculation, Fenton's oxidation and air stripping pretreatments
Authors: Smaoui Yosr , Mlaik Najwa , Bouzid Jalel , Sayadi Sami
Published: October 2017

In Tunisia, the anaerobic digestion process is regarded as a new alternative for the treatment of landfill leachate (LFL). Raw LFL contained high amounts of organic matter, high ammonia concentrations and low biodegradability. In order to improve anaerobic conditions and biogas yields, pretreatment using coagulation‐flocculation, Fenton oxidation (FO) and air stripping processes were investigated and compared in terms of biogas production. Air stripping process was optimized using Response Surface Methodology (RSM). Central Composite Design (CCD) was used with three factors. Under optimized conditions, removals of 85% ammonia, 26% chemical oxygen demand (COD) were achieved. Coagulation‐flocculation provided an increase in the effluent biodegradability with 46% of COD reduction. Fenton's oxidation allowed reducing 48% COD, 30% of biological oxygen demand (BOD5). The effect of pretreatments was investigated with the biochemical methane potential (BMP) assay. A comparison of three different pretreatment methods of LFL for biogas production was performed. Air stripping was demonstrated as providing a better biogas yield than other pretreatments which reached 588 mL/g CODint. The best methane yield was obtained using air stripping pretreatment under optimized conditions. It can result in more robust and effective anaerobic digestion. © 2017 American Institute of Chemical Engineers Environ Prog, 37: 1041–1049, 2018
The Impact of Self‐Reported Impulsivity on the Course of Weight Is Mediated by Disinhibited Eating
Authors: Legenbauer Tanja , Müller Astrid , de Zwaan Martina , Fischer Charlotte , Burgmer Ramona , Herpertz Stephan
Published: October 2017

This study investigates the impact of impulsivity and the mediating role of disinhibited eating behaviour (DEB) on weight and weight trajectories in a large data set including obese non‐treatment seeking individuals (obese control, n = 138) and obese individuals who were either receiving a conventional treatment program (n = 227) or bariatric surgery (n = 123). Data was assessed one, 4 and 9 years after baseline including self‐reports for impulsivity and DEB. Results suggest a significant association between impulsivity and body mass index, which is partially mediated by DEB. Longitudinally, the influence of impulsivity on the course of weight after 9 years was fully mediated by DEB in obese control but not in the treatment groups. The results indicate an interplay between impulsivity and DEB with respect to obesity. Further research is needed to clarify how the mediation works and when it exerts its effect, in order to identify those that might profit from a specific (impulsivity‐reducing) training. Copyright © 2017 John Wiley & Sons, Ltd and Eating Disorders Association.
Anaerobic biotransformation of N-methyl perfluorobutanesulfonamido ethanol and N-ethyl perfluorooctanesulfonamido ethanol
Authors: Lange Cleston C.
Published: October 2017

Some fluorochemical products are manufactured using N-methyl perfluorobutanesulfonamido ethanol (MeFBSE), a short-chain replacement for perfluorooctyl-based chemistries N-methyl and N-ethyl perfluorooctanesulfonamido ethanols (EtFOSE). The present study shows for the first time the anaerobic biodegradation of MeFBSE and EtFOSE in municipal digester sludge under methanogenic conditions. Both MeFBSE and EtFOSE were incubated for 108 d with anaerobic digester sludge. Although sterile controls did not remove MeFBSE, it was degraded in live sludge. The loss of MeFBSE coincided with production of N-methyl perfluorobutanesulfonamido acetate (MeFBSAA) and perfluorobutane sulfinate (PFBSI). The biodegradation appeared biphasic, with pseudo first-order loss between days 0 and 70, resulting in approximately 75% removal but no further depletion of MeFBSE between days 70 and 108. By day 108 MeFBSAA and PFBSI accounted for 57 and 40 mol% of initial dose, respectively. Mass balance values in live cultures on days 0, 10, 21, 29, 70, and 108 were 103, 92, 94, 100, 93, and 122%, respectively. The apparent first-order biodegradation rate constant for MeFBSE over the first 70 d was 0.0194 d−1, and the apparent half-life was 35.8 d. Incubation of EtFOSE with live digester sludge resulted in low-level formation of N-ethyl perfluorooctane-sulfonamido acetate and perfluorooctane sulfinate, which did not form in sterile controls. Although it was not measurably lost, 2 to 3% loss of EtFOSE was calculated based on product concentrations. The total product formation rate constant was determined by first-order kinetic evaluation over the first 72 d to estimate a first-order biodegradation rate constant for EtFOSE at 0.000374 d−1, and the apparent half-life time was 1860 d. Environ Toxicol Chem 2018;37:768–779. © 2017 SETAC
Factors affecting the dissipation of pharmaceuticals in freshwater sediments
Authors: Al-Khazrajy Omar S.A. , Bergström Ed , Boxall Alistair B.A.
Published: October 2017

Degradation is one of the key processes governing the impact of pharmaceuticals in the aquatic environment. Most studies on the degradation of pharmaceuticals have focused on soil and sludge, with fewer exploring persistence in aquatic sediments. We investigated the dissipation of 6 pharmaceuticals from different therapeutic classes in a range of sediment types. Dissipation of each pharmaceutical was found to follow first-order exponential decay. Half-lives in the sediments ranged from 9.5 (atenolol) to 78.8 (amitriptyline) d. Under sterile conditions, the persistence of pharmaceuticals was considerably longer. Stepwise multiple linear regression analysis was performed to explore the relationships between half-lives of the pharmaceuticals, sediment physicochemical properties, and sorption coefficients for the compounds. Sediment clay, silt, and organic carbon content and microbial activity were the predominant factors related to the degradation rates of diltiazem, cimetidine, and ranitidine. Regression analysis failed to highlight a key property which may be responsible for observed differences in the degradation of the other pharmaceuticals. The present results suggest that the degradation rate of pharmaceuticals in sediments is determined by different factors and processes and does not exclusively depend on a single sediment parameter. Environ Toxicol Chem 2018;37:829–838. © 2017 SETAC
Anisotropic adaptive stabilized finite element solver for RANS models
Authors: Sari J. , Cremonesi F. , Khalloufi M. , Cauneau F. , Meliga P. , Mesri Y. , Hachem E.
Published: October 2017

Aerodynamic characteristics of various geometries are predicted using a finite element formulation coupled with several numerical techniques to ensure stability and accuracy of the method. First, an edge‐based error estimator and anisotropic mesh adaptation are used to detect automatically all flow features under the constraint of a fixed number of elements, thus controlling the computational cost. A variational multiscale‐stabilized finite element method is used to solve the incompressible Navier‐Stokes equations. Finally, the Spalart‐Allmaras turbulence model is solved using the streamline upwind Petrov‐Galerkin method. This paper is meant to show that the combination of anisotropic unsteady mesh adaptation with stabilized finite element methods provides an adequate framework for solving turbulent flows at high Reynolds numbers. The proposed method was validated on several test cases by confrontation with literature of both numerical and experimental results, in terms of accuracy on the prediction of the drag and lift coefficients as well as their evolution in time for unsteady cases.
Toxicological parameters of albino rats fed with extruded snacks from Aerial yam (Dioscoria bulbifera) and African breadfruit seed (Treculia africana)
Authors: Olatoye Kazeem K. , Arueya Gibson L.
Published: October 2017

In this study, safety of novel food from aerial yam and Treculia africana, underutilized food materials with high‐nutritive value and health benefits were investigated. Animal experiment involving the use of thirty (30) male albino rats was conducted for 28 days.Thereafter, rats in all groups were sacrificed and blood samples collected for biochemical analysis and hematological assay. Some vital organs were harvested and used for histological analysis. Biochemical and hematological parameters were not significantly p ≤ .05 different among the treatment and controls. However there was an increase in monocytes, which is a reflection of immune boosting potential of the novel snack. No significant pathological changes were observed in liver and kidney of rats fed with this snack. Rats showed no signs of toxicity within the study period. These findings suggest that product may be safe and useful as an Immune adjuvant.
Mechanisms of lysophosphatidylcholine‐induced demyelination: A primary lipid disrupting myelinopathy
Authors: Plemel Jason R. , Michaels Nathan J. , Weishaupt Nina , Caprariello Andrew V. , Keough Michael B. , Rogers James A. , Yukseloglu Aran , Lim Jaehyun , Patel Vikas V. , Rawji Khalil S. , Jensen Samuel K. , Teo Wulin , Heyne Belinda , Whitehead Shawn N. , Stys Peter K. , Yong V. Wee
Published: October 2017

For decades lysophosphatidylcholine (LPC, lysolecithin) has been used to induce demyelination, without a clear understanding of its mechanisms. LPC is an endogenous lysophospholipid so it may cause demyelination in certain diseases. We investigated whether known receptor systems, inflammation or nonspecific lipid disruption mediates LPC‐demyelination in mice. We found that LPC nonspecifically disrupted myelin lipids. LPC integrated into cellular membranes and rapidly induced cell membrane permeability; in mice, LPC injury was phenocopied by other lipid disrupting agents. Interestingly, following its injection into white matter, LPC was cleared within 24 hr but by five days there was an elevation of endogenous LPC that was not associated with damage. This elevation of LPC in the absence of injury raises the possibility that the brain has mechanisms to buffer LPC. In support, LPC injury in culture was significantly ameliorated by albumin buffering. These results shed light on the mechanisms of LPC injury and homeostasis.
Glucocorticoids promote a glioma stem cell‐like phenotype and resistance to chemotherapy in human glioblastoma primary cells: Biological and prognostic significance
Authors: Kostopoulou Ourania N. , Mohammad Abdul‐Aleem , Bartek Jiri , Winter Julia , Jung Masany , Stragliotto Giuseppe , Söderberg‐Nauclér Cecilia , Landázuri Natalia
Published: October 2017

Glioma stem cells (GSCs) are glioblastoma (GBM) cells that are resistant to therapy and can give rise to recurrent tumors. The identification of patient‐related factors that support GSCs is thus necessary to design effective therapies for GBM patients. Glucocorticoids (GCs) are used to treat GBM‐associated edema. However, glucocorticoids participate in the physiological response to psychosocial stress, which has been linked to poor cancer prognosis. This raises concern that glucocorticoids affect the tumor and GSCs. Here, we treated primary human GBM cells with dexamethasone and evaluated GC‐driven changes in cell morphology, proliferation, migration, gene expression, secretory activity and growth as neurospheres. Dexamethasone treatment of GBM cells appeared to promote the development of a GSC‐like phenotype and conferred resistance to physiological stress and chemotherapy. We also analyzed a potential correlation between GC treatment and tumor recurrence after surgical excision in a population‐based consecutive cohort of 48 GBM patients, adjusted for differences in known prognostic factors concerning baseline and treatment characteristics. In this cohort, we found a negative correlation between GC intake and progression‐free survival, regardless of the MGMT methylation status. In conclusion, our findings raise concern that treatment of GBM with GCs may compromise the efficacy of chemotherapy and may support a GSC population, which could contribute to tumor recurrence and the poor prognosis of the disease.
Surface modification of bulk titanium substrates for biomedical applications via low‐temperature microwave hydrothermal oxidation
Authors: Cheng Alice , Goodwin W. Brandon , deGlee Ben M. , Gittens Rolando A. , Vernon Jonathan P. , Hyzy Sharon L. , Schwartz Zvi , Sandhage Kenneth H. , Boyan Barbara D.
Published: October 2017

Micro‐to‐nanoscale surface topographies of orthopaedic and dental implants can affect fluid wetting and biological response. Nanoscale features can be superimposed on microscale roughness of titanium (Ti) surfaces at high temperatures, resulting in increased osteoblast differentiation. However, high temperatures can compromise mechanical properties of the bulk material. Here, we have developed a novel low‐temperature microwave hydrothermal (MWHT) oxidation process for nanomodification of microrough (SLA) Ti surfaces. Nanoscale protuberances (20 –100 nm average diameter) were generated on SLA surfaces via MWHT treatment at 200°C in H2O, or in aqueous solutions of H2O2 or NH4OH, for times ranging from 1 to 40 h. The size, shape, and crystalline content of the nanoprotuberances varied with the solution used and treatment time. The hydrophilicity of all MWHT‐modified surfaces was dramatically enhanced. MG63 and normal human osteoblasts (NHOsts) were cultured on MWHT‐treated SLA surfaces. While most responses to MWHT‐modified surfaces were comparable to those seen on SLA controls, the MWHT‐generated nanotopography reduced osteocalcin production by NHOst cells, suggesting that specific nanotopographic characteristics differentially mediate osteoblast phenotypic expression. MWHT processing provides a scalable, low‐temperature route for tailoring nanoscale topographies on microroughened titanium implant surfaces with significantly enhanced wetting by water, without degrading the microscale surface structure of such implants. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 782–796, 2018.
Stimulation of a calcified cartilage connecting zone by GDF‐5‐augmented fibrin hydrogel in a novel layered ectopic in vivo model
Authors: Diederichs Solvig , Renz Yvonne , Hagmann Sébastien , Lotz Benedict , Seebach Elisabeth , Richter Wiltrud
Published: October 2017

Tissue engineering approaches for reconstructing full‐depth cartilage defects need to comprise a zone of calcified cartilage to tightly anchor cartilage constructs into the subchondral bone. Here, we investigated whether growth and differentiation factor‐5‐(GDF‐5)‐augmented fibrin hydrogel can induce a calcified cartilage‐layer in vitro that seamlessly connects cartilage‐relevant biomaterials with bone tissue. Human bone marrow stromal cells (BMSCs) were embedded in fibrin hydrogel and subjected to chondrogenesis with TGF‐β with or without GDF‐5 before constructs were implanted subcutaneously into SCID mice. A novel layered ectopic in vivo model was developed and GDF‐5‐augmented fibrin with BMSCs was used to glue hydrogel and collagen constructs onto bone disks to investigate formation of a calcified cartilage connecting zone. GDF‐5 significantly enhanced ALP activity during in vitro chondrogenesis while ACAN and COL2A1 mRNA, proteoglycan‐, collagen‐type‐II‐ and collagen‐type‐X‐deposition remained similar to controls. Pellets pretreated with GDF‐5 mineralized faster in vivo and formed more ectopic bone. In the novel layered ectopic model, GDF‐5 strongly supported calcified cartilage formation that seamlessly connected with the bone. Pro‐chondrogenic and pro‐hypertrophic activity makes GDF‐5‐augmented fibrin an attractive bioactive hydrogel with high potential to stimulate a calcified cartilage connecting zone in situ that might promote integration of cartilage scaffolds with bone. Thus, GDF‐5‐augmented fibrin hydrogel promises to overcome poor fixation of biomaterials in cartilage defects facilitating their long‐term regeneration. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 2214–2224, 2018.
In vitro study on the deterioration of polypropylene hernia repair meshes
Authors: Gil Dmitry , Rex James , Reukov Vladimir , Vertegel Alexey
Published: October 2017

Despite the relative safety of the procedure, hernia repairs are often associated with chronic post‐operative pain. Although this complication has been linked among others to mesh deterioration, details of the processes that lead this deterioration are still unknown. This work aims to bridge this gap by analyzing the chemical, physical and structural alterations in hernia repair meshes exposed to oxidative stress in vitro. Here, we developed a methodology to characterize effect of oxidation stress on structure and properties of polymeric hernia repair meshes. It was shown that structural changes in polypropylene meshes exposed to oxidative stress may involve formation of cross‐links between the polymer chains, chain scissions, and hydrogen bonds between the carboxyl groups, which are formed in the material during the oxidation. These effects result in mesh stiffening, ultimately leading to chronic post‐operative pain. Moreover, we demonstrated that Composix meshes are more vulnerable to the oxidative stress when compared with UltraPro meshes. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 2225–2234, 2018.
Genetically Determined Later Puberty Impacts Lowered Bone Mineral Density in Childhood and Adulthood
Authors: Cousminer Diana L , Mitchell Jonathan A , Chesi Alessandra , Roy Sani M , Kalkwarf Heidi J , Lappe Joan M , Gilsanz Vicente , Oberfield Sharon E , Shepherd John A , Kelly Andrea , McCormack Shana E , Voight Benjamin F , Zemel Babette S , Grant Struan FA
Published: October 2017

Later puberty associates with lower areal bone mineral density (aBMD), and both are risk factors for osteoporosis. However, the association between puberty timing–associated genetic variants and aBMD during development, and the causal relationship between puberty timing and aBMD, remain uncharacterized. We constructed sex-specific polygenic risk scores (GRS) consisting of 333 genetic variants associated with later puberty in European-descent children in the Bone Mineral Density in Childhood Study (BMDCS), consisting of a longitudinal cohort with up to seven assessments (n = 933) and a cross-sectional cohort (n = 486). These GRS were tested for associations with age- and sex-specific aBMD Z-scores at the lumbar spine (LS), femoral neck (FN), total hip, and distal radius, accounting for clinical covariates using sex-stratified linear mixed models. The causal relationship between puberty timing and aBMD was tested in the BMDCS and in publicly available adult data (GEFOS consortium) using two-sample Mendelian randomization (MR). The puberty-delaying GRS was associated with later puberty and lower LS-aBMD in the BMDCS in both sexes (combined beta ± SE = –0.078 ± 0.024; p = 0.0010). In the MR framework, the puberty-delaying genetic instrument also supported a causal association with lower LS-aBMD and FN-aBMD in adults of both sexes. Our results suggest that pubertal timing is causal for diminished aBMD in a skeletal site- and sex-specific manner that tracks throughout life, potentially impacting later risk for osteoporosis, which should be tested in future studies. © 2017 American Society for Bone and Mineral Research.
Biodegradation of polyethylene via complete solubilization by the action of Pseudomonas fluorescens, biosurfactant produced by Bacillus licheniformis and anionic surfactant
Authors: Mukherjee Shritama , RoyChaudhuri Uttam , Kundu Patit P
Published: October 2017

BACKGROUND

Long hydrocarbon (∼CH2) chain, absence of polar bonds and highly hydrophobic nature of polyethylene, make it one of most difficult environmental pollutants to degrade. In the present study, commercially available polyethylenes were treated with biosurfactant produced by Bacillus licheniformis, anionic surfactant and bacterially treated with Pseudomonas fluorescens in different combinations to achieve higher biodegradation.

RESULTS

Polyethylene was slightly oxidized by P. fluorescens in the first month and the oxidation of polyethylene induced by the biosurfactant during the second month was enhanced by the presence of lower amounts of carbonyl groups as observed in FTIR analysis. During the third month, highly oxidized polyethylene was entirely solubilized by the action of 10% SDS forming two‐layered liquid consisting of yellow oil‐like liquid as upper layer and an aqueous colourless lower layer. Biodegradable aliphatic acids, alcohols and short hydrocarbon molecules of 10–30 carbon chains were identified by GC–MS analysis in the aqueous solution. Weight loss of 7.13 ± 0.05% was also observed in polyethylene samples which were treated with SDS in the first month, then bacterially treated with P. fluorescens in the second month and finally treated with biosurfactant in the third month.

CONCLUSIONS

Polyethylene became biodegradable after complete solubilization in water by treating consecutively with Pseudomonas fluorescens in the first month, then with biosurfactant in the second month and finally treating with 10% sodium dodecyl sulphate (SDS) at 60 °C for the third month. Simultaneous treatment of polyethylene with P. fluorescens, surfactant and biosurfactant has a tremendous effect on the oxidation and biodegradation of polyethylene. © 2017 Society of Chemical Industry