bluuebunny/crossref_metadata_2025 huggingface dataset:
The Magnetohydrodynamic Effect and Its Associated Material Designs for Biomedical Applications: A State‐of‐the‐Art Review
Authors: Gregory Thomas Stanley , Cheng Rui , Tang Guoyi , Mao Leidong , Tse Zion Tsz Ho
Published: February 2016

The presented article discusses recent advances in biomedical applications of classical magnetohydrodynamics (MHD), with a focus on operating principles and associated material considerations. These applications address novel approaches to common biomedical problems from microparticle sorting for lab‐on‐a‐chip devices to advanced physiological monitoring techniques. 100 papers in the field of MHDs are reviewed with a focus on studies with direct biomedical applications. The body of literature is categorized into three primary areas of research including material considerations for MHD applications, MHD actuation devices, and MHD sensing techniques. The state of the art in the field is examined and research topics are connected to provide a wide view of the field of biomedical MHDs. As this field develops, the need for advanced simulation and material design will continue to increase in importance in order to further expand its reach to maturity. As the field of biomedical MHDs continues to grow, advances toward microscale transitions will continue to be made, maintaining its clinically driven nature and moving toward real‐world applications.
Unprecedented J‐Aggregated Dyes in Pure Organic Solvents
Authors: Manzano Hegoi , Esnal Ixone , Marqués‐Matesanz Tamara , Bañuelos Jorge , López‐Arbeloa Iñigo , Ortiz María J. , Cerdán Luis , Costela Angel , García‐Moreno Inmaculada , Chiara Jose Luis
Published: February 2016

The design and synthesis of the first organic dyes enabling spontaneous formation of stable J‐aggregates in common organic solvents without additives is described. The new dyes are O‐BODIPYs with a B‐spiranic 4,4‐diacyloxyl substitution pattern. Key to the effectiveness of the J‐aggregation process is the high conformational rigidity of the B‐spiranic molecular design as well as the orthogonal disposition of the B‐diacyloxyl substituent and the meso‐aryl group with respect to the mean plane of the boradiazaindacene. Atomistic simulations, both in vacuum and in a solvent cage, support the dynamics of the J‐aggregation process as well as its dependence on the alkylation pattern of the BODIPY chromophore. A detailed analysis of the photophysical and laser properties of the new dyes provides convincing evidence for the unambiguous assignment of these J‐aggregates and their dependence on the environmental conditions.
Remote‐Controllable Molecular Knob in the Mesomorphic Helical Superstructures
Authors: Kim Dae‐Yoon , Lee Sang‐A , Park Minwook , Choi Yu‐Jin , Yoon Won‐Jin , Kim Jin Soo , Yu Yeon‐Tae , Jeong Kwang‐Un
Published: February 2016

A programed light‐responsive chiral liquid crystal (LC) containing four photochromic azobenzene moieties covalently connected to a central bicyclic chiral core (abbreviated as AZ4ICD) is newly designed, precisely synthesized, and efficiently applied as a remote‐controllable molecular knob for the optically tunable thin film. First of all, phase evolutions and ordered structures of AZ4ICD are systematically investigated by a combination of thermal, microscopic, scattering, and simulation techniques. Wide‐angle X‐ray diffractions of oriented AZ4ICD samples indicate that the AZ4ICD molecule itself basically forms layer structures: one is a low‐ordered chiral smectic A LC phase (SmA*) with 5.61 nm layer periodicity at high temperatures, and two highly ordered smectic crystal (SmCr1 and SmCr2) phases are subsequently formed at lower temperatures with the anticlinically tilted molecular packing structures. The helical superstructures of chiral nematic LC phase (N*) can be spontaneously constructed by doping AZ4ICD chiral agents into the achiral nematic molecules. Due to the bent conformational geometry of AZ4ICD, the thermal window of blue LC phase (BP) is expanded by stabilizing the double twisted cylindrical building blocks. Remote‐controllable phase transformations in the mesomorphic helical superstructures are demonstrated by tuning the wavelength of light.
High‐Performance Hybrid White Organic Light‐Emitting Diodes with Superior Efficiency/Color Rendering Index/Color Stability and Low Efficiency Roll‐Off Based on a Blue Thermally Activated Delayed Fluorescent Emitter
Authors: Wu Zhongbin , Luo Jiajia , Sun Ning , Zhu Liping , Sun Hengda , Yu Ling , Yang Dezhi , Qiao Xianfeng , Chen Jiangshan , Yang Chuluo , Ma Dongge
Published: February 2016

Thermally activated delayed fluorescence (TADF)‐based white organic light‐emitting diodes (WOLEDs) are highly attractive because the TADF emitters provide a promising alternative route to harvest triplet excitons. One of the major challenges is to achieve superior efficiency/color rendering index/color stability and low efficiency roll‐off simultaneously. In this paper, high‐performance hybrid WOLEDs are demonstrated by employing an efficient blue TADF emitter combined with red and green phosphorescent emitters. The resulting WOLED shows the maximum external quantum efficiency, current efficiency, and power efficiency of 23.0%, 51.0 cd A−1, and 51.7 lm W−1, respectively. Moreover, the device exhibits extremely stable electroluminescence spectra with a high color rendering index of 89 and Commission Internationale de L'Eclairage coordinates of (0.438, 0.438) at the practical brightness of 1000 cd m−2. The achievement of these excellent performances is systematically investigated by versatile experimental and theoretical evidences, from which it is concluded that the utilization of a blue‐green‐red cascade energy transfer structure and the precise manipulation of charges and excitons are the key points. It can be anticipated that this work might be a starting point for further research towards high‐performance hybrid WOLEDs.
Gelatin Microspheres as Vehicle for Cardiac Progenitor Cells Delivery to the Myocardium
Authors: Feyen Dries A. M. , Gaetani Roberto , Deddens Janine , van Keulen Danielle , van Opbergen Chantal , Poldervaart Michelle , Alblas Jacqueline , Chamuleau Steven , van Laake Linda W. , Doevendans Pieter A. , Sluijter Joost P. G.
Published: February 2016

Inadequate cell retention and survival in cardiac stem cell therapy seems to be reducing the therapeutic effect of the injected stem cells. In order to ameliorate their regenerative effects, various biomaterials are being investigated for their potential supportive properties. Here, gelatin microspheres (MS) are utilized as microcarriers to improve the delivery and therapeutic efficacy of cardiac progenitor cells (CPCs) in the ischemic myocardium. The gelatin MS, generated from a water‐in‐oil emulsion, are able to accommodate the attachment of CPCs, thereby maintaining their cardiogenic potential. In a mouse model of myocardial infarction, we demonstrated the ability of these microcarriers to substantially enhance cell engraftment in the myocardium as indicated by bioluminescent imaging and histological analysis. However, despite an observed tenfold increase in CPC numbers in the myocardium, echocardiography, and histology reveals that mice treated with MS‐CPCs show marginal improvement in cardiac function compared to CPCs only. Overall, a straightforward and translational approach is developed to increase the retention of stem cells in the ischemic myocardium. Even though the current biomaterial setup with CPCs as cell source does not translate into improved therapeutic action, coupling this developed technology with stem cell‐derived cardiomyocytes can lead to an effective remuscularization therapy.
Enantiodivergent Brucine Diol‐Catalyzed 1,3‐Dipolar Cycloaddition of Azomethine Ylides with α,β‐Unsaturated Ketones
Authors: Li Jian‐Yuan , Kim Hun Young , Oh Kyungsoo
Published: February 2016

Enantiodivergent catalyst systems were developed using metals with different ionic radii and a multifunctional brucine diol (BD) ligand. The catalytic use of purported 1:1 Cu‐BD complexes in the 1,3‐dipolar cycloaddition of azomethine ylides with chalcones resulted in the selective formation of endo‐pyrrolidines in 87–96% ees with an absolute stereochemical outcome of (2R,3S,4R,5S). In contrast, an opposite absolute stereochemical outcome was observed by using the catalysts derived from Ag(I) salts and BD. The demonstration of enantiodivergent approaches to a broad class of substrates/reaction types underlines their synthetic value in asymmetric synthesis.

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Effect of Graphite Oxide Dispersion Evaluated with Multifractal on Mechanical Properties and Thermal Stability of Poly(3hydroxybutyrate‐co‐4hydroxybutyrate)/Graphite Oxide Biocomposites
Authors: Yang Jia , Wang Yuli , Chen Qiang , Qin Gang , Liu Shuzheng
Published: February 2016

Poly(3hydroxybutyrate‐co‐4hydroxybutyrate) [P(3HB‐co‐4HB)]/graphite oxide (GO) composites were fabricated using a solution mixing method. The GO structures in the composites were analyzed by using transmission electron microscopy, Raman spectroscopy, and X‐ray diffraction. The fracture morphology of the samples was evaluated by the multifractal, and the effect of GO dispersion on the mechanical properties and the thermal stability were discussed for the P(3HB‐co‐4HB) and the composites. It was found that the interlayer spacing of the GO increased due to the intercalation of the polymer into the GO platelets. As the GO content increased, the relative multifractal spectrum increased, but the mechanical properties declined for the composites, indicating that the filler agglomeration effect overcame the reinforcement benefits for the high loadings of the GO. Moreover, both good dispersion and high content of the GO platelets increased the thermal stability of the composites. Therefore, the relative multifractal spectrum width of the fracture morphology was related to the mechanical properties and the thermal stability of the composites.
One‐Dimensional Ferroelectric Nanostructures: Synthesis, Properties, and Applications
Authors: Liang Longyue , Kang Xueliang , Sang Yuanhua , Liu Hong
Published: February 2016

One‐dimensional (1D) ferroelectric nanostructures, such as nanowires, nanorods, nanotubes, nanobelts, and nanofibers, have been studied with increasing intensity in recent years. Because of their excellent ferroelectric, ferroelastic, pyroelectric, piezoelectric, inverse piezoelectric, ferroelectric‐photovoltaic (FE‐PV), and other unique physical properties, 1D ferroelectric nanostructures have been widely used in energy‐harvesting devices, nonvolatile random access memory applications, nanoelectromechanical systems, advanced sensors, FE‐PV devices, and photocatalysis mechanisms. This review summarizes the current state of 1D ferroelectric nanostructures and provides an overview of the synthesis methods, properties, and practical applications of 1D nanostructures. Finally, the prospects for future investigations are outlined.
From Lithium‐Oxygen to Lithium‐Air Batteries: Challenges and Opportunities
Authors: Geng Dongsheng , Ding Ning , Hor T. S. Andy , Chien Sheau Wei , Liu Zhaolin , Wuu Delvin , Sun Xueliang , Zong Yun
Published: February 2016

Lithium‐air batteries have become a focus of research on future battery technologies. Technical issues associated with lithium‐air batteries, however, are rather complex. Apart from the sluggish oxygen reaction kinetics which demand efficient oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) catalysts, issues are also inherited from the nature of an open battery system and the use of reactive metal lithium as anode. Lithium‐air batteries, which exchange oxygen directly with ambient air, face more challenges due to the additional oxidative agents of moisture, carbon dioxide, etc. which degrade the metal lithium anode, deteriorating the performance of the batteries. In order to improve the cycling performance one must hold a full picture of lithium‐oxygen electrochemistry in the presence of carbon dioxide and/or moisture and fully understand the fundamentals of chemistry reactions therein. Recent advances in the exploration of the effect of moisture and CO2 contaminants on Li‐O2 batteries are reviewed, and the mechanistic understanding of discharge/charge process in O2 at controlled level of moisture and/or CO2 are illustrated. Prospects for development opportunities of Li‐air batteries, insight into future research directions, and guidelines for the further development of rechargeable Li‐air batteries are also given.
Piperidine‐Catalyzed 1,3‐Dipolar Cycloaddition of Diazoesters to Enones
Authors: Huang Jiayao , Wu Minghu , Hu Liqiang , Guo Haibin , Sun Shaofa
Published: February 2016

An organocatalytic 1,3‐dipolar cycloaddition of diazoesters to enones has been developed. The reaction is catalyzed by a secondary amine to give substituted pyrazoles in high yields and excellent regioselectivity.
Total Synthesis of Coibacin D by Using Enantioselective Allylation and Metathesis Reactions
Authors: Kolská Kristýna , Ghavre Mukund , Pour Milan , Hybelbauerová Simona , Kotora Martin
Published: February 2016

The first asymmetric total synthesis of coibacin D, a metabolite isolated from the marine cyanobacterium cf. Oscillatoria sp., was achieved in six steps starting from simple hept‐6‐en‐1‐ol. The synthetic strategy was based on a chiral Brønsted acid catalyzed enantioselective allylboration and a Ru‐carbene complex catalyzed sequential ring‐closing and cross‐metathesis strategy. The recorded spectroscopic data and the sign of the optical rotation of the synthesized coibacin D were in agreement with the published data for the isolated compound, which confirmed the proposed structure and absolute configuration.
Ethnicity influences disease characteristics and symptom severity in allergic rhinitis patients in Malaysia
Authors: Amini Peyman , Abdullah Maha , Seng Lee Sing , Karunakaran Thanusha , Hani Norzhafarina , Bakar Saraiza Abu , Latiff Amir Hamzah Abdul , Fong Seow Heng , Yeow Yap Yoke
Published: February 2016

Background

The number of available reports regarding the influence of ethnicity on clinical features of allergic rhinitis (AR), especially disease severity in tropical climates, is limited. We aimed to compare clinical parameters and disease severity in AR patients of different ethnicities.

Methods

Malay, Chinese, and Indian AR patients (n = 138) with confirmed sensitivity to Dermatophagoides pteronyssinus, Dematophagoides farinae, and Blomia tropicalis were tested for mite‐specific immunoglobulin E (sIgE) levels. A detailed questionnaire was used to collect data on nasal symptom score (NSS), ocular symptom score (OSS), sum of symptoms score (SSS), quality of life score (QLS), symptomatic control score (SCS), and total sum of scores (TSS) and correlate the derived data with patients’ demography, mite‐polysensitivity, and sIgE levels.

Results

AR‐related symptoms were most severe in Malays and least in Chinese (p < 0.01). Age (r = 0.516 to 0.673, p < 0.05) and duration of AR (r = 0.635 to 0.726, p < 0.01) correlated positively with severity domains (NSS, SSS, QLS, and TSS) in Chinese. Duration of concurrent allergies was highest in Malays (p < 0.05). Polysensitivity predicted increased sIgE levels in Malays (r = 0.464 to 0.551, p < 0.01) and Indians (r = 0.541 to 0.645, p < 0.05) but affected NSS, SSS, and TSS only in Indians (r = 0.216 to 0.376, p < 0.05). sIgE levels were lowest among Chinese but correlated strongly with NSS, OSS, SSS, and TSS (r = 0408 to 0.898, p < 0.05).

Conclusion

Clinical parameters in AR may be influenced by race. Symptoms were most severe among Malays but did not correlate with other variables examined. Although Indian ethnicity did not impact disease severity, duration of concurrent allergies and mite‐polysensitivity was associated with more severe disease. Age, duration of disease, and sIgE levels may be useful indicators of disease severity in Chinese.
Orthogonale Assemblierung von Proteinen auf DNA‐Nanostrukturen mithilfe von Relaxasen
Authors: Sagredo Sandra , Pirzer Tobias , Aghebat Rafat Ali , Goetzfried Marisa A. , Moncalian Gabriel , Simmel Friedrich C. , de la Cruz Fernando
Published: February 2016

DNA‐bindende Proteine erlauben die sequenzspezifische Modifikation von DNA‐basierten Nanostrukturen. Hier untersuchen wir die Eignung von Relaxaseproteinen – speziell TrwC, TraI und MobA – für die Nanofabrikation. Relaxasen sind Komponenten des bakteriellen Konjugationsmechanismus, bei dem Plasmide zwischen Bakterien ausgetauscht werden, wobei sie an DNA durch eine kovalente Phosphotyrosinbindung binden. Wir untersuchen die Anbindung der Relaxasen an zwei prototypische DNA‐Origamistrukturen – stabförmige Sechs‐Helix‐Bündel und flache rechteckige Origami‐Platten. Die Proteine zeigen orthogonale Anbindungseigenschaften mit Ausbeuten von 40–50 % pro Bindestelle, vergleichbar mit alternativen Funktionalisierungsmethoden. Die Ausbeuten variieren zwischen den Origamistrukturen und hängen auch von der Position der Bindestellen ab. Aufgrund ihrer Spezifität für einzelsträngige Zielsequenzen und ihrer orthogonalen Anbindeeigenschaften sind Relaxasen eine einzigartige Erweiterung des molekularen Werkzeugkastens für die Modifikation von DNA‐Nanostrukturen.
Kristallstruktur‐geleitetes Design selbstorganisierender RNA‐Nanodreiecke
Authors: Boerneke Mark A. , Dibrov Sergey M. , Hermann Thomas
Published: February 2016

RNA‐Nanotechnologie nutzt RNA‐Strukturmotive zur Konstruktion von Molekülarchitekturen im Nanomaßstab, die sich durch selektive Basenpaar‐Wechselwirkungen selbstorganisieren. Hier berichten wir über Kristallstruktur‐geleitetes Design von stabilen RNA‐Nanodreiecken, die sich durch Selbstorganisation aus kurzen Oligonukleotiden bilden. Eine Kristallstrukturbestimmung eines Nanodreiecks von 81 Nukleotiden mit 2.6 Å Auflösung zeigt das bisher kleinste in sich geschlossene Nanoobjekt, das vollständig aus doppelsträngiger RNA besteht. Da die Eckbausteine des Nanodreiecks Ligand‐bindende RNA‐Schalter enthalten, ergibt sich die Möglichkeit, die Selbstorganisation und Dissoziation durch externe Liganden zu kontrollieren.
Krypton Derivatization of an O2‐Tolerant Membrane‐Bound [NiFe] Hydrogenase Reveals a Hydrophobic Tunnel Network for Gas Transport
Authors: Kalms Jacqueline , Schmidt Andrea , Frielingsdorf Stefan , van der Linden Peter , von Stetten David , Lenz Oliver , Carpentier Philippe , Scheerer Patrick
Published: February 2016

[NiFe] hydrogenases are metalloenzymes catalyzing the reversible heterolytic cleavage of hydrogen into protons and electrons. Gas tunnels make the deeply buried active site accessible to substrates and inhibitors. Understanding the architecture and function of the tunnels is pivotal to modulating the feature of O2 tolerance in a subgroup of these [NiFe] hydrogenases, as they are interesting for developments in renewable energy technologies. Here we describe the crystal structure of the O2‐tolerant membrane‐bound [NiFe] hydrogenase of Ralstonia eutropha (ReMBH), using krypton‐pressurized crystals. The positions of the krypton atoms allow a comprehensive description of the tunnel network within the enzyme. A detailed overview of tunnel sizes, lengths, and routes is presented from tunnel calculations. A comparison of the ReMBH tunnel characteristics with crystal structures of other O2‐tolerant and O2‐sensitive [NiFe] hydrogenases revealed considerable differences in tunnel size and quantity between the two groups, which might be related to the striking feature of O2 tolerance.
Orthogonal Protein Assembly on DNA Nanostructures Using Relaxases
Authors: Sagredo Sandra , Pirzer Tobias , Aghebat Rafat Ali , Goetzfried Marisa A. , Moncalian Gabriel , Simmel Friedrich C. , de la Cruz Fernando
Published: February 2016

DNA‐binding proteins are promising reagents for the sequence‐specific modification of DNA‐based nanostructures. Here, we investigate the utility of a series of relaxase proteins—TrwC, TraI, and MobA—for nanofunctionalization. Relaxases are involved in the conjugative transfer of plasmids between bacteria, and bind to their DNA target sites via a covalent phosphotyrosine linkage. We study the binding of the relaxases to two standard DNA origami structures—rodlike six‐helix bundles and flat rectangular origami sheets. We find highly orthogonal binding of the proteins with binding yields of 40–50 % per binding site, which is comparable to other functionalization methods. The yields differ for the two origami structures and also depend on the position of the binding sites. Due to their specificity for a single‐stranded DNA target, their orthogonality, and their binding properties, relaxases are a uniquely useful addition to the toolbox available for the modification of DNA nanostructures with proteins.
Oxide‐Modified Nickel Photocatalysts for the Production of Hydrocarbons in Visible Light
Authors: Zhao Yufei , Zhao Bo , Liu Jinjia , Chen Guangbo , Gao Rui , Yao Siyu , Li Mengzhu , Zhang Qinghua , Gu Lin , Xie Jinglin , Wen Xiaodong , Wu Li‐Zhu , Tung Chen‐Ho , Ma Ding , Zhang Tierui
Published: February 2016

Metallic nickel nanostructures that were partially decorated by discrete nickel oxide layers were fabricated by in situ reduction of calcinated Ni‐containing layered double hydroxide nanosheets, the structure of which was confirmed by extended X‐ray absorption fine structure spectroscopy, X‐ray photoelectron spectroscopy, and transmission electron microscopy. The existence of the abundant interfaces between the surface Ni oxide overlayer and metallic Ni altered the geometric/electronic structure of the Ni nanoparticles, making them apt for CO activation under light irradiation. Most importantly, the unique structure favors the C−C coupling reaction on its surface, which confers the catalyst unexpected reaction power towards higher hydrocarbons at moderate reaction conditions. This study leads to a green and sustainable approach for the photocatalytic production of highly valuable chemical fuels.
Identification of microsatellite loci and examination of genetic structure for the endangered springsnails Juturnia kosteri and Pyrgulopsis roswellensis in the Chihuahuan Desert
Authors: Holste Danielle R. , Inoue Kentaro , Lang Brian K. , Berg David J.
Published: February 2016

Desert spring ecosystems harbour many endemic species that are threatened with extinction owing to human activities. Springsnails (superfamily Truncatelloidea) are among the most diverse freshwater snail groups in desert springs of western North America. They occupy geographically narrow ranges, often consisting of a single spring or spring complex.

Microsatellite markers were developed via high‐throughput de novo sequencing for two endangered springsnail species, Juturnia kosteri and Pyrgulopsis roswellensis, endemic to springs on Bitter Lake National Wildlife Refuge (BLNWR) near Roswell, New Mexico, USA. Genetic diversity, population structure, effective population size (Ne), and historic demography were assessed in two populations for each species.

A large number of putative markers were identified, of which 14 loci for J. kosteri and 18 loci for P. roswellensis showed polymorphism. Genetic diversity and Ne were greater in P. roswellensis than J. kosteri. Significant genetic differentiation (FST = 0.187–0.288) was found among populations for both species, indicating currently limited gene flow. Neither species showed signs of recent population bottlenecks.

Analyses with microsatellite markers revealed fine‐scale population genetic structure in both species, unlike a previous study using mitochondrial DNA sequences. Although these species co‐occur on BLNWR, slightly different genetic characteristics between them suggest that they may have different evolutionary and demographic histories. Small Ne relative to census size indicates strong genetic drift in these populations. Future efforts should be directed to identifying causes of such strong drift.

Because there are limited numbers of microsatellite markers available for springsnails, the markers identified in this study should be useful for congeners via cross‐species amplification. Understanding current genetic variation and structure of these species is not only required for species recovery, but will also be useful for comparisons among many aquatic organisms endemic to springs of western North America.

Copyright © 2016 John Wiley & Sons, Ltd.
The Functional Anatomy of the Carpometacarpal Complex in Anthropoids and Its Implications for the Evolution of the Hominoid Hand
Authors: Selby Michael S. , Simpson Scott W. , lovejoy C. Owen
Published: February 2016

Previously, we described several features of the carpometacarpal joints in extant large‐bodied apes that are likely adaptations to the functional demands of vertical climbing and suspension. We observed that all hominids, including modern humans and the 4.4‐million‐year‐old hominid Ardipithecus ramidus, lacked these features. Here, we assess the uniqueness of these features in a large sample of monkey, ape, and human hands. These new data provide additional insights into the functional adaptations and evolution of the anthropoid hand. Our survey highlights a series of anatomical adaptations that restrict motion between the second and third metacarpals (MC2 and MC3) and their associated carpals in extant apes, achieved via joint reorganization and novel energy dissipation mechanisms. Their hamate‐MC4 and ‐MC5 joint surface morphologies suggest limited mobility, at least in Pan. Gibbons and spider monkeys have several characters (angled MC3, complex capitate‐MC3 joint topography, variably present capitate‐MC3 ligaments) that suggest functional convergence in response to suspensory locomotion. Baboons have carpometacarpal morphology suggesting flexion/extension at these joints beyond that observed in most other Old World monkeys, probably as an energy dissipating mechanism minimizing collision forces during terrestrial locomotion. All hominids lack these specializations of the extant great apes, suggesting that vertical climbing was never a central feature of our ancestral locomotor repertoire. Furthermore, the reinforced carpometacarpus of vertically climbing African apes was likely appropriated for knuckle‐walking in concert with other novel potential energy dissipating mechanisms. The most parsimonious explanation of the structural similarity of these carpometacarpal specializations in great apes is that they evolved independently. Anat Rec, 299:583–600, 2016. © 2016 Wiley Periodicals, Inc.
Production of α‐ketobutyrate using engineered Escherichia coli via temperature shift
Authors: Zhang Chenglin , Qi Junsheng , Li Yanjun , Fan Xiaoguang , Xu Qingyang , Chen Ning , Xie Xixian
Published: February 2016

Alpha‐ketobutyrate has been widely used in medicine and food additive industry. Because chemical and enzymatic methods are associated with many deficiencies, the recent focus shifted to fermentation for the production of α‐ketobutyrate. In this study, a genetically engineered strain THRDΔrhtAΔilvIH/pWSK29‐ilvA was constructed, starting from an L‐threonine‐producing strain, by overexpressing threonine dehydratase (TD), reducing α‐ketobutyrate catabolism and L‐threonine export. The shake flask cultivation of THRDΔrhtAΔilvIH/pWSK29‐ilvA allowed the production of 16.2 g/L α‐ketobutyrate. Accumulation of α‐ketobutyrate severely inhibited the cell growth. To develop a better TD expression system and avoid the usage of the expensive inducer IPTG, a temperature‐induced plasmid pBV220‐ilvA was selected to transform the strain THRDΔrhtAΔilvIH for α‐ketobutyrate production. The initial temperature was maintained at 35°C to guarantee normal cell growth, and then elevated to 40°C to induce the expression of TD. Under optimized conditions, the α‐ketobutyrate titer reached 40.8 g/L after 28 h of fermentation, with a productivity of 1.46 g/L/h and a yield of 0.19 g/g glucose, suggesting large‐scale production potential. Biotechnol. Bioeng. 2016;113: 2054–2059. © 2016 Wiley Periodicals, Inc.
A study of the competency of third year medical students to interpret biochemically based clinical scenarios using knowledge and skills gained in year 1 and 2
Authors: S. Gowda Veena Bhaskar , Nagaiah Bhaskar Hebbani , Sengodan Bharathi
Published: February 2016

Medical students build clinical knowledge on the grounds of previously obtained basic knowledge. The study aimed to evaluate the competency of third year medical students to interpret biochemically based clinical scenarios using knowledge and skills gained during year 1 and 2 of undergraduate medical training. Study was conducted on year 3 MBBS students at AIMST University, Malaysia. Clinical scenarios (25) were constructed and administered to student volunteers, making sure at least one question from each system of year 2 was represented. Feedback was obtained on a five‐point Likert scale regarding perception of learning biochemistry in MBBS year 1 versus 2. Mean score of test was 18 (72.11%). Performance was comparatively better in questions related to topics learnt in year 1 and reinforced in year 2 compared to those learnt for first time in year 2. In the feedback obtained, 31% strongly agreed and 56% agreed understanding the subject was helped more by learning biochemistry in year 2 than in year 1. Likewise, 36% strongly agreed and 56% agreed appreciating the importance of biochemistry in patient diagnosis was helped more by learning biochemistry in year 2 than year 1. Thirty one percent strongly agreed and 54% agreed that year 1 biochemistry would have been more relevant if case discussions were done simultaneously. Students retain basic science subjects better and appreciate the importance of basic sciences in patient diagnosis if they are reinforced in the context of clinical situations. © 2016 by The International Union of Biochemistry and Molecular Biology, 44:202–207, 2016.
Taraxerol 4‐Methoxybenzoate, an in vitro Inhibitor of Photosynthesis Isolated from Pavonia multiflora A. St‐Hil. (Malvaceae)
Authors: Lopes Leandra Gobira , Tavares Gabriela Lopes , Thomaz Luciana Dias , Sabino José Ricardo , Borges Keyller Bastos , Vieira Paulo Cezar , Veiga Thiago André Moura , de Souza Borges Warley
Published: February 2016

A phytochemical study of Pavonia multiflora A. St‐Hil. (Malvaceae) led to the isolation through chromatographic techniques of 10 secondary metabolites: vanillic acid (1), ferulic acid (2), p‐hydroxybenzoic acid (3), p‐coumaric acid (4), loliolide (5), vomifoliol (6), 4,5‐dihydroblumenol A (7), 3‐oxo‐α‐ionol (9), blumenol C (10), and taraxerol 4‐methoxybenzoate (8), the latter being a novel metabolite. Their structures were identified by 1H‐ and 13C‐NMR, using one‐ and two‐dimensional techniques, and X‐ray crystallography. In this work, we report the effect of compounds 5 and 8 on several photosynthetic activities in an attempt to search for new compounds as potential herbicide agents that affect photosynthesis. Both compounds inhibited the electron flow from H2O to methyl viologen; therefore, they act as Hill reaction inhibitors. Using polarographic techniques and studies of the fluorescence of chlorophyll a, the interaction sites of these compounds were located at photosystem II.
Essential Oil Composition of Phagnalon sordidum (L.) from Corsica, Chemical Variability and Antimicrobial Activity
Authors: Brunel Marion , Vitrac Caroline , Costa Jean , Mzali Fatima , Vitrac Xavier , Muselli Alain
Published: February 2016

The chemical composition of Phagnalon sordidum (L.) essential oil was investigated for the first time using gas chromatography and chromatography/mass spectrometry. Seventy‐six compounds, which accounted for 87.9% of the total amount, were identified in a collective essential oil of P. sordidum from Corsica. The main essential oil components were (E)‐β‐caryophyllene (14.4%), β‐pinene (11.0%), thymol (9.0%), and hexadecanoic acid (5.3%). The chemical compositions of essential oils from 19 Corsican locations were investigated. The study of the chemical variability using statistical analysis allowed identifying direct correlation between the three populations of P. sordidum widespread in Corsica and the essential oil compositions they produce. The in vitro antimicrobial activity of P. sordidum essential oil was evaluated and it exhibited a notable activity on a large panel of clinically significant microorganisms.
Chemical Composition and Allelopathic Potential of Essential Oils from Tipuana tipu (Benth.) Kuntze Cultivated in Tunisia
Authors: El Ayeb‐Zakhama Asma , Sakka‐Rouis Lamia , Bergaoui Afifa , Flamini Guido , Jannet Hichem Ben , Harzallah‐Skhiri Fethia
Published: February 2016

In Tunisia, Tipuana tipu (Benth.) Kuntze is an exotic tree, which was introduced many years ago and planted as ornamental street, garden, and park tree. The present work reported, for the first time, the chemical composition and evaluates the allelopathic effect of the hydrodistilled essential oils of the different parts of this tree, viz., roots, stems, leaves, flowers, and pods gathered in the area of Sousse, a coastal region, in the East of Tunisia. In total, 86 compounds representing 89.9 – 94.9% of the whole oil composition, were identified in these oils by GC‐FID and GC/MS analyses. The root essential oil was clearly distinguished for its high content in sesquiterpene hydrocarbons (β‐caryophyllene, 1 (44); 24.1% and germacrene D, 2 (53); 20.0%), while those obtained from pods, leaves, stems, and flowers were dominated by non‐terpene hydrocarbons. The most important ones were n‐tetradecane (41, 16.3%, pod oil), 1,7‐dimethylnaphthalene (43, 15.6%, leaf oil), and n‐octadecane (77, 13.1%, stem oil). The leaf oil was rich in the apocarotene (E)‐β‐ionone (4 (54); 33.8%), and the oil obtained from flowers was characterized by hexahydrofarnesylacetone (5 (81); 19.9%) and methyl hexadecanoate (83, 10.2%). Principal component and hierarchical cluster analyses separated the five essential oils into three groups and two subgroups, each characterized by the major oil constituents. Contact tests showed that the germination of lettuce seeds was totally inhibited by the root essential oil tested at 1 mg/ml. The inhibitory effect on the shoot and root elongation varied from −1.6% to −32.4%, and from −2.5% to −64.4%, respectively.
Active‐Site‐Directed Inhibitors of Prolyl Oligopeptidase Abolish Its Conformational Dynamics
Authors: López Abraham , Herranz‐Trillo Fátima , Kotev Martin , Gairí Margarida , Guallar Víctor , Bernadó Pau , Millet Oscar , Tarragó Teresa , Giralt Ernest
Published: February 2016

Deciphering conformational dynamics is crucial for understanding the biological functions of proteins and for designing compounds targeting them. In particular, providing an accurate description of microsecond–millisecond motions opens the opportunity for regulating protein–protein interactions (PPIs) by modulating the dynamics of one interacting partner. Here we analyzed the conformational dynamics of prolyl oligopeptidase (POP) and the effects of active‐site‐directed inhibitors on the dynamics. We used an integrated structural biology approach based on NMR spectroscopy and SAXS experiments complemented by MD simulations. We found that POP is in a slow equilibrium in solution between open and closed conformations, and that inhibitors effectively abolished this equilibrium by stabilizing the enzyme in the closed conformation.
Stenting of the left pulmonary artery after palliation of hypoplastic left heart syndrome
Authors: Noonan Patrick , Kudumula Vikram , Anderson Ben , Ramchandani Bharat , Miller Paul , Dhillon Rami , Mehta Chetan , Stumper Oliver
Published: February 2016

Background

Left pulmonary artery stenosis and hypoplasia is a well‐recognized complication following surgical palliation of hypoplastic left heart syndrome. These lesions produce increased after load in a circulation in series so need to be effectively treated.

Methods

Between 2000 and 2011, 86 patients after surgical palliation for hypoplastic left heart syndrome had left pulmonary artery stents implanted. Median age at implantation was 4.7(1.3–15.2) years and median weight was 16.4(9.3–55.2) kg. Uncovered peripheral vascular stents were implanted (median diameter 10(8–15) mm). This is a retrospective review of the incidence of in‐stent restenosis over the medium to long term.

Results

During primary stenting procedures, there were 2/88(2.3%) major complications of stent migration with no stroke or mortality. Follow‐up was for a median period of 4.1(0.5–13.4) years. Follow‐up catheter procedures were performed after a median time of 2.3(0.02–9.6) years in 59 patients (68.6%). 55/59(93.2%) had at most mild restenosis (≤10% loss of stent lumen) and 47/59(79.6%) had no evidence of any restenosis at all caused by neointimal in‐growth. Freedom from reintervention was 77% at 5 years including stent dilation to compensate for somatic growth. Freedom from reintervention for restenosis was 93% at 5 years. Restenosis was successfully treated with standard balloon angioplasty or restenting. There was only 1/94 (1.1%) major complication in the follow‐up catheterizations of stent embolization with successful transcatheter retrieval.

Conclusions

Stenting of the left pulmonary artery after Norwood/Fontan palliation is safe and effective. Stents can be redilated to match somatic growth. The incidence of neointimal proliferation is extremely low and can be addressed by balloon dilation or stent implantation. © 2016 Wiley Periodicals, Inc.
Very late stent thrombosis with second generation drug eluting stents compared to bare metal stents: Network meta‐analysis of randomized primary percutaneous coronary intervention trials
Authors: Philip Femi , Stewart Susan , Southard Jeffrey A.
Published: February 2016

Background

The relative safety of drug‐eluting stents (DES) and bare‐metal stents (BMS) in primary percutaneous coronary intervention (PPCI) in ST elevation myocardial infarction (STEMI) continues to be debated. The long‐term clinical outcomes between second generation DES and BMS for primary percutaneous coronary intervention (PCI) using network meta‐analysis were compared. Methods: Randomized controlled trials comparing stent types (first generation DES, second generation DES, or BMS) were considered for inclusion. A search strategy used Medline, Embase, Cochrane databases, and proceedings of international meetings. Information about study design, inclusion criteria, and sample characteristics were extracted. Network meta‐analysis was used to pool direct (comparison of second generation DES to BMS) and indirect evidence (first generation DES with BMS and second generation DES) from the randomized trials. Results: Twelve trials comparing all stents types including 9,673 patients randomly assigned to treatment groups were analyzed. Second generation DES was associated with significantly lower incidence of definite or probable ST (OR 0.59, 95% CI 0.39–0.89), MI (OR 0.59, 95% CI 0.39–0.89), and TVR at 3 years (OR 0.50: 95% CI 0.31–0.81) compared with BMS. In addition, there was a significantly lower incidence of MACE with second generation DES versus BMS (OR 0.54, 95% CI 0.34–0.74) at 3 years. These were driven by a higher rate of TVR, MI and stent thrombosis in the BMS group at 3 years. There was a non‐significant reduction in the overall and cardiac mortality [OR 0.83, 95% CI (0.60–1.14), OR 0.88, 95% CI (0.6–1.28)] with the use of second generation DES versus BMS at 3 years. Conclusions: Network meta‐analysis of randomized trials of primary PCI demonstrated lower incidence of MACE, MI, TVR, and stent thrombosis with second generation DES compared with BMS. © 2016 Wiley Periodicals, Inc.
A rectovaginal fistula after treatment with bevacizumab. A dangerous side effect needing emergency treatment
Authors: Galanopoulos Michail , Ladias Spyridon , Tzannetakou Xanthippi , Tsigaridas Athanasios , Sarafis Alexandros , Liatsos Christos , Kalafatis Evangelos
Published: February 2016

Key Clinical Message

Despite its effectiveness in the treatment of malignant tumors, bevacizumab is associated with a variety of side effects such as the formation of fistulas (i.e., tracheoesophageal, colovaginal, or rectovaginal). It is important to recognize immediately the emergence of this entity in order to discontinue bevacizumab permanently and treat the fistula.
One‐Pot Deoxygenation of Fructose to Furfuryl Alcohol by Sequential Dehydration and Decarbonylation
Authors: Dai Jinhang , Fu Xing , Zhu Liangfang , Tang Jinqiang , Guo Xiawei , Hu Changwei
Published: February 2016

Fructose was deoxygenated to furfuryl alcohol (FFA) by tandem dehydration and decarbonylation in one pot over the AlCl3⋅6 H2O/Pd(OAc)2 catalyst combination to give a high FFA yield of 40.6 %. AlCl3⋅6 H2O behaves as an effective Lewis acid to catalyze the dehydration of fructose to 5‐hydroxymethylfurfural (HMF), and subsequently, Pd(OAc)2 catalyzes the removal of a CO moiety from HMF to produce FFA selectively. The hydroxyl group on the HMF intermediate was stabilized by poly(1‐vinyl‐2‐pyrrolidinone) through an intermolecular hydrogen bond, which accelerated the dehydration of fructose and inhibited the hydrogenation of HMF by formic acid. The decarbonylation of HMF was promoted and the unwanted decomposition of fructose was inhibited through the use of 4 Å molecular sieves. This research highlights a “one‐pot” catalytic system to transform renewable carbohydrates into fine chemicals by tandem dehydration and decarbonylation reactions without the separation or purification of HMF.
Fabrication of Chitosan Membranes with High Flux by Magnetic Alignment of In Situ Generated Fe3O4
Authors: Xing Ruisi , Wu Hong , Zhao Cuihong , Gomaa Hassan , Zhao Jing , Pan Fusheng , Jiang Zhongyi
Published: February 2016

Hybrid membranes with in situ generated Fe3O4 were fabricated by combining infiltration and magnetic alignment. Typically, a chitosan (CS) membrane containing iron ions was produced and then immediately immersed in NaOH solution. Fe3O4 was in situ generated when OH− infiltrated into the CS networks, and meanwhile a magnetic field was applied to tune their distribution. The characterization results indicated that Fe3O4 decreased the crystallinity of CS, favored the generation of a free‐volume cavity, and aligned along the magnetic lines. For comparison, hybrid membranes without application of the magnetic field were produced. When used in pervaporation for ethanol dehydration, the hybrid membrane with magnetic alignment exhibited an enhanced flux compared to that without magnetic alignment.
Effect of Additives on the Pulsed‐Galvanostatic Electrodeposition of Iron Nanoparticles from Formamide Media
Authors: Baloch Marya , López Carmen M.
Published: February 2016

Iron‐based nanoparticles have many technological applications ranging from energy storage to biomedicine. Their use in energy‐storage devices depends on their efficient incorporation into functional electrodes, a purpose for which pulsed‐galvanostatic electrodeposition (PG‐ECD) is an ideal method. In this study, we used PG‐ECD to prepare Fe‐nanoparticle electrodes from formamide media, and we investigated the morphology of the electrodeposits and the electrochemical properties of the plating solutions as a function of the additives used. We found evidence of unusual behavior for the sodium dodecyl sulfate additive, which acted as a supporting electrolyte under our chosen conditions, and fairly typical behavior for acetylacetone and poly(ethylene glycol) dimethyl ether. All three additives showed that they could be used to control the morphology of the electrodeposits, albeit through mechanisms in some cases different than those typical in aqueous solutions.
Improving the Electrocatalytic Activity of Pt Monolayer Catalysts for Electrooxidation of Methanol, Ethanol and Ammonia by Tailoring the Surface Morphology of the Supporting Core
Authors: Liu Jie , Chen Bin , Ni Zhengyang , Deng Yida , Han Xiaopeng , Hu Wenbin , Zhong Cheng
Published: February 2016

The front cover artwork is provided by the group of Dr. Cheng Zhong, Tianjin University (Tianjin, China). The image shows the presence of a high density of catalytically active defect sites such as surface atomic steps on the flower‐like Pt‐based particles, as revealed by atomic‐resolution spherical‐aberration‐corrected transmission electron microscopy. Read the full text of the Article at 10.1002/celc.201500451.
Comparison of MLR, OPLS, and SVM as potent chemometric techniques used to estimate in vitro metabolic stability
Authors: Ulenberg Szymon , Belka Mariusz , Bączek Tomasz
Published: February 2016

In the drug development pipeline, metabolic stability is not only one of the most limiting factors when it comes to drug candidate approval but is also one of the most resource‐consuming and time‐consuming ones regarding in vitro studies. With the popularization of the in silico approach in the drug discovery process and the application of many excellent chemometric techniques in predicting the properties of compounds, the authors focused on developing a model able to estimate the in vitro half‐life of arylpiperazine derivatives. The aim of the presented study was to develop a regression model and compare the performance of three potent methods (multiple linear regression (MLR), orthogonal partial least squares (OPLS), and support vector machine (SVM)) when predicting in vitro half‐life values. Of the three studied techniques, SVM proved to be the most accurate (RMSESVM = 0.054 for both sets, RMSEMLR = 0.072 for both sets, and RMSEOPLS = 0.073 for both sets) and provided the best predictability (Q2 = 0.8410; for MLR, Q2 = 0.7263; and for OPLS, Q2 = 0.7490). Hence, SVM regression provides valuable predictions and seems to be a promising technique not only for developing regression models but also for studying quantitative structure‐metabolic stability relationships. Copyright © 2016 John Wiley & Sons, Ltd.
New Concepts for Increasing the Efficiency in Directed Evolution of Stereoselective Enzymes
Authors: Sun Zhoutong , Wikmark Ylva , Bäckvall Jan‐E. , Reetz Manfred T.
Published: February 2016

Directed evolution of stereo‐ and regioselective enzymes constitutes a prolific source of catalysts for asymmetric transformations in organic chemistry. In this endeavor (iterative) saturation mutagenesis at sites lining the binding pocket of enzymes has emerged as the method of choice, but uncertainties regarding the question of how to group many residues into randomization sites and how to choose optimal upward pathways persist. Two new approaches promise to beat the numbers problem effectively. One utilizes a single amino acid as building block for the randomization of a 10‐residue site, the other also employs only one but possibly different amino acid at each position of a 9‐residue site. The small but smart libraries provide highly enantioselective epoxide hydrolase or lipase mutants, respectively.
Redox Switches for Single‐Molecule Magnet Activity: An Ab Initio Insight
Authors: Vieru Veacheslav , Chibotaru Liviu F.
Published: February 2016

A dinuclear CoII complex (1) featuring unprecedented anodic and cathodic switches for single‐molecule magnet (SMM) activity has been recently investigated (J. Am. Chem. Soc. 2013, 135, 14670). The presence of sandwiched radicals in different oxidation states of this compound mediates magnetic coupling between the high‐spin (S=3/2) cobalt ions, which gives rise to SMM activity in both the oxidized ([1(OEt2)]+) and reduced ([1]−) states. This feature represents the first example of a SMM exhibiting fully reversible, dual ON/OFF switchability. Here we apply ab initio and broken‐symmetry DFT calculations to elucidate the mechanisms responsible for magnetic properties and magnetization blocking in these compounds. It is found that due to the strong delocalization of the magnetic molecular orbital, there is a strong antiferromagnetic interaction between the radical and cobalt ions. The lack of high axiality of the cobalt centres explains why these compounds possess slow relaxation of magnetization only in an applied dc magnetic field.