bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bioinspired Production of Antibacterial Sucrose Isomerase‐Sponge for the Synthesis of Isomaltulose
Authors: Wu Lingtian , Qiu Juanjuan , Wu Shanshan , Liu Xiaoliu , Liu Chao , Xu Zheng , Li Sha , Xu Hong 
Published: November 2016

AbstractIsomaltulose is a new functional sweetener that possesses biological characteristics and can be obtained by enzymatic synthesis using sucrose as substrate. In this study, the sucrose isomerase (SIase) was successfully immobilized on the sponge synthesized with ϵ‐poly‐l‐lysine and gelatin. The inhibition zones proved that the sponge possessed a significant bacteriostatic function, which can effectively prevent the collapse of the scaffolds of the immobilized enzymes. The immobilized SIase activity reached up to 71.58 U g−1 (the SIase loading was about 153.43 mg g−1), and the activity recovery was approximately 84.50%. After immobilization, the optimum pH of SIase decreased from 6.0 to 5.5 and the optimum temperature increased from 30 °C to 40 °C. The affinity of SIase to substrate was basically unchanged. Immobilized SIase still exhibited more than 90% sucrose conversion after 13 consecutive cycles, which indicated that it had a good operational stability. Furthermore, the immobilized SIase has the potential for isomaltulose production, with 200 g L−1 sucrose solution as its substrate in the food industry. Isomaltulose was isolated in 83.58% yield and high purity (97.3%).magnified image
N‐Iodosuccinimide‐Promoted Rapid Access to Indeno[1,2‐c]pyrroles via [3+2] Annulation of Enamine‐alkynes
Authors: Santhi Jampani , Baire Beeraiah 
Published: November 2016

AbstractWe have developed a metal‐free, N‐iodosuccinimide (NIS)‐promoted, cascade strategy for the efficient synthesis of biologically important indeno[1,2‐c]pyrroles via a [3+2] annulation process of enamine‐alkynes. This methodology had shown a very broad scope for diversely functionalized enamines and alkynes. We have also developed a one‐pot, multicomponent strategy for the direct synthesis of indeno‐pyrroles from diynones via enamine‐alkynes. Control experiments supported the involvement of NIS as an electrophilic activator via an ionic mechanism rather than a radical pathway.magnified image
A Kinase‐Independent One‐Pot Multienzyme Cascade for an Expedient Synthesis of Guanosine 5′‐Diphospho‐d‐mannose
Authors: Pfeiffer Martin , Bulfon Dominik , Weber Hansjoerg , Nidetzky Bernd 
Published: November 2016

AbstractBiomimetic synthesis routes towards the important natural d‐mannosyl donor guanosine 5′‐diphospho‐d‐mannose (GDP‐Man) rely on kinase‐catalyzed nucleotide triphosphate (NTP)‐dependent phosphorylations of d‐mannose (Man), to give d‐mannose 6‐phosphate or α‐d‐mannose 1‐phosphate (αMan 1‐P) as an intermediate product. A GDP‐Man synthesis not requiring the kinase/NTP system would be practical and cost‐effective. Here, we have developed a multienzyme cascade towards GDP‐Man, characterized in that αMan 1‐P was obtained by a diastereoselective phosphatase‐catalyzed phosphorylation of Man. α‐d‐Glucose 1‐phosphate (αGlc 1‐P), prepared in situ through phosphorylase‐catalyzed conversion of sucrose in the presence of inorganic phosphate, was used as an expedient phosphoryl donor. The incipient αMan 1‐P and guanosine triphosphate (GTP) were converted into GDP‐Man by a highly manno compared to gluco selective nucleotidyltransferase. Pyrophosphatase was additionally required to hydrolyze the pyrophosphate released from the GTP, thus driving the reaction towards GDP‐Man. The enzymatic cascade was operated with the αMan 1‐P and the GDP‐Man formation decoupled from one another (sequential mode) or having all steps run concurrently (simultaneous mode). Detailed time course analysis revealed that kinetic pull due to the constant removal of the intermediate αMan 1‐P in simultaneous‐mode reactions was important to promote phosphorylation of Man from αGlc 1‐P in high efficiency, avoiding loss of sugar 1‐phosphates by hydrolysis. Under optimized conditions for the one‐pot transformation involving four enzymes, 100 mM (67 g L−1) GDP‐Man was prepared from 140 mM sucrose and phosphate, using 400 mM Man as the phosphoryl acceptor. The product was recovered by anion‐exchange and size‐exclusion chromatography in ≥95% purity in about 50% yield (100 mg). These results demonstrate for the first time the practical use of a phosphorylase‐phosphatase combi‐catalyst as an alternative to the canonical kinase for the anomeric phosphorylation of the sugar substrate in nucleoside diphospho‐sugar synthesis. Phosphorylation from inorganic phosphate via the intermediate αGlc 1‐P rather than from NTP, particularly GTP, appears advantageous specifically in cases where the sugar acceptor is a bulk commodity that can be applied in suitable excess to the phosphatase reaction.magnified image
Gold(I)‐Catalyzed Carboaminations of Allenes by N‐Allyltetrahydro‐β‐carbolines: An Experimental and Theoretical Study
Authors: Gobé Valérian , Dousset Maxime , Retailleau Pascal , Gandon Vincent , Guinchard Xavier 
Published: November 2016

AbstractN‐Allyltetrahydro‐β‐carbolines bearing a pendant allene undergo unprecedented gold(I)‐catalyzed cyclizations proceeding with an allyl migration from the nitrogen to the allene moiety. The initial product of the gold‐catalyzed cyclization evolves either via isomerization or Cope rearrangement, leading to different scaffolds. Density function theory (DFT) calculations established that the allyl migration occurs in an asynchronous suprafacial manner.magnified image
Live birth sex ratios and father's geographic origins in Jerusalem, 1964–1976
Authors: Groeger J. , Opler M. , Kleinhaus K. , Perrin M. C. , Calderon‐Margalit R. , Manor O. , Paltiel O. , Conley D. , Harlap S. , Malaspina D. 
Published: November 2016

AbstractObjectiveTo examine whether ancestry influenced sex ratios of offspring in a birth cohort before parental antenatal sex selection influenced offspring sex.MethodsWe measured the sex ratio as the percent of males according to countries of birth of paternal and maternal grandfathers in 91,459 live births from 1964 to 1976 in the Jerusalem Perinatal Study. Confidence limits (CI) were computed based on an expected sex ratio of 1.05, which is 51.4% male.ResultsOf all live births recorded, 51.4% were male. Relative to Jewish ancestry (51.4% males), significantly more males (1,761) were born to Muslim ancestry (54.5, 95% CI = 52.1–56.8, P = 0.01). Among the former, sex ratios were not significantly associated with paternal or maternal age, education, or offspring's birth order. Consistent with a preference for male offspring, the sex ratio decreased despite increasing numbers of births over the 13‐year period. Sex ratios were not affected by maternal or paternal origins in North Africa or Europe. However, the offspring whose paternal grandfathers were born in Western Asia included fewer males than expected (50.7, 50.1‐51.3, P = 0.02), whether the father was born abroad (50.7) or in Israel (50.8). This was observed for descendents of paternal grandfathers born in Lebanon (47.6), Turkey (49.9), Yemen & Aden (50.2), Iraq (50.5), Afghanistan (50.5), Syria (50.6), and Cyprus (50.7); but not for those from India (51.5) or Iran (51.9). The West Asian group showed the strongest decline in sex ratios with increasing paternal family size.ConclusionsA decreased sex ratio associated with ancestry in Western Asia is consistent with reduced ability to bear sons by a subset of Jewish men in the Jerusalem cohort. Lower sex ratios may be because of pregnancy stress, which may be higher in this subgroup. Alternatively, a degrading Y chromosome haplogroup or other genetic or epigenetic differences on male germ lines could affect birth ratios, such as differential exposure to an environmental agent, dietary differences, or stress. Differential stopping behaviors that favor additional pregnancies following the birth of a daughter might exacerbate these lower sex ratios.
Robust graft survival and normalized dopaminergic innervation do not obligate recovery in a Parkinson disease patient
Authors: Kordower Jeffrey H. , Goetz Christopher G. , Chu Yaping , Halliday Glenda M. , Nicholson Daniel A. , Musial Timothy F. , Marmion David J. , Stoessl A. Jon , Sossi Vesna , Freeman Thomas B. , Olanow C. Warren 
Published: November 2016

ObjectiveThe main goal of dopamine cell replacement therapy in Parkinson disease (PD) is to provide clinical benefit mediated by graft survival with nigrostriatal reinnervation. We report a dichotomy between graft structure and clinical function in a patient dying 16 years following fetal nigral grafting.MethodsA 55‐year‐old levodopa‐responsive woman with PD received bilateral putaminal fetal mesencephalic grafts as part of an NIH‐sponsored double‐blind sham‐controlled trial. The patient never experienced clinical benefit, and her course was complicated by the development of graft‐related dyskinesias. Fluorodopa positron emission tomography demonstrated significant increases postgrafting bilaterally. She experienced worsening of parkinsonism with severe dyskinesias, and underwent subthalamic nucleus deep brain stimulation 8 years after grafting. She died 16 years after transplantation.ResultsPostmortem analyses confirmed the diagnosis of PD and demonstrated >300,000 tyrosine hydroxylase (TH)‐positive grafted cells per side with normalized striatal TH‐immunoreactive fiber innervation and bidirectional synaptic connectivity. Twenty‐seven percent and 17% of grafted neurons were serine 129‐phosphorylated α‐synuclein positive in the left and right putamen, respectively.InterpretationThese findings represent the largest number of surviving dopamine neurons and the densest and most widespread graft‐mediated striatal dopamine reinnervation following a transplant procedure reported to date. Despite this, clinical recovery was not observed. Furthermore, the grafts were associated with a form of dyskinesias that resembled diphasic dyskinesia and persisted in the off‐medication state. We hypothesize that the grafted cells produced a low level of dopamine sufficient to cause a levodopa‐independent continuous form of diphasic dyskinesias, but insufficient to provide an antiparkinsonian benefit. ANN NEUROL 2017;81:46–57
Spontaner Aufbau einer organisch‐anorganischen Nukleinsäure‐Z‐DNA‐Doppelhelix‐Struktur
Authors: Kulikov Vladislav , Johnson Naomi A. B. , Surman Andrew , Hutin Marie , Kelly Sharon M. , Hezwani Mohammed , Long De‐Liang , Meyer Gerd , Cronin Leroy 
Published: November 2016

AbstractWir berichten hier über ein hybrides organisch‐anorganisches Polyoxometallat, Na2[(HGMP)2Mo5O15]⋅7 H2O (1) (mit GMP=Guanosinmonophosphat), das sich spontan zu einer Struktur zusammenfügt, deren Dimensionen jenen der natürlich vorkommenden linkshändigen Z‐Form der DNA verblüffend ähnlich sind. Die Helixparameter in der Kristallstruktur dieser neuen Verbindung, wie Anstieg pro Windung und helikale Verdrillung pro Dimer, sind nahezu identisch zur DNA, was einen eingehenden Vergleich von beiden Strukturen erlaubt. Zirkulardichroismus (CD) in Lösung zeigt, dass Verbindung 1 auch in Lösung ausgedehnte Sekundärstrukturen aufweist. Gelelektrophorese‐Untersuchungen weisen die Bildung nichtkovalenter Addukte mit natürlichen Plasmiden nach. Damit können wir einen Weg aufzeigen, auf dem einfache, hybride organisch‐anorganische Monomere, wie in Verbindung 1, sich spontan zu einer Doppelhelix zusammenlagern können, ohne dass dazu eine kovalent gebundene lineare Sequenz von Nuklein‐Säure‐Base‐Paaren nötig wäre.
Supramolecular Nanofibrillar Thermoreversible Hydrogel for Growth and Release of Cancer Spheroids
Authors: Li Yunfeng , Khuu Nancy , Gevorkian Albert , Sarjinsky Sharon , Therien‐Aubin Heloise , Wang Yihe , Cho Sangho , Kumacheva Eugenia 
Published: November 2016

AbstractGrowth of three‐dimensional cancer spheroids (CSs) in man‐made hydrogels mimicking natural extracellular matrix is an important and challenging task. Herein, we report on a supramolecular temperature‐responsive hydrogel designed for the growth and subsequent release of CSs. A filamentous hydrogel was formed at 37 °C from an aqueous suspension of cellulose nanocrystals surface‐functionalized with temperature‐responsive polymer molecules. The encapsulation of cells in the hydrogel enabled effective growth of CSs with dimensions determined by the concentration of cellulose nanocrystals in the hydrogel. On demand release of CSs without loss of cell viability and spheroid integrity was achieved upon hydrogel cooling. The tumorigenic properties of the released CSs were examined by encapsulating and re‐growing them in fibrin hydrogel. The results in this work can be used in fundamental cancer research and in cancer drug screening.
Microencapsulation of tea tree oil by spray‐drying with methyl cellulose as the emulsifier and wall material together with chitosan/alginate
Authors: Zhang Song , Chen Juan , Yin Xueqiong , Wang Xuyu , Qiu Bining , Zhu Li , Lin Qiang 
Published: November 2016

ABSTRACTAmphiphilic methyl cellulose (MC) was used as the emulsifier and the internal wall material to increase the microencapsulation efficiency (ME) of tea tree oil (TTO) and the stability of the emulsion for spray‐drying. The results of microscopy images, zeta potential, and microencapsulation efficiency indicated that the wall material components affected the morphology, stability, and ME of the microcapsules. The microcapsules with the wall materials of MC/chitosan (CTS)/alginate (ALG) were spherical and had higher ME than those with monocomponent or bicomponents of MC, CTS, or ALG, or triple components of MC/ALG/CTS. Spray drying conditions were optimized to find the optimum microencapsulation conditions. The highest ME 89.4% and the highest oil embedding rate (ER) 90.4% were obtained through spray‐dying the emulsion of 0.8 mL TTO embraced by 0.4 g MC, 0.6 g CTS, and 3 g ALG at the drying conditions of inlet air temperature 210 °C, needling frequency 2 s, and pump flow rate 55 r/min. Microencapsulation obviously decreased the release of TTO. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44662.
Preparation and thermomechanical properties of nanocrystalline cellulose reinforced poly(lactic acid) nanocomposites
Authors: Zhang Ping , Gao De , Zou Pingping , Wang Bingtao 
Published: November 2016

ABSTRACTA two‐step process was developed to prepare nanocrystalline cellulose (NCC) reinforced poly(lactic acid) (PLA) nanocomposites using polyethylene glycol (PEG) as a compatibilizer. It was composed of solvent mixing and melt blending. The NCC was well dispersed in the PLA matrix. A network was formed at high NCC‐to‐PEG ratio at which the amount of the PEG was not enough to cover all the surfaces of the NCC. The formation of the network was confirmed by the occurrence of a plateau for the storage modulus at low frequency. The incorporation of the PEG and NCC could improve the crystallinity of the PLA. The elongation at break increased from 11.0% for the neat PLA to 106.0% for the composites including 6 wt % NCC, impact strength was improved from 0.864 to 2.64 kJ m−2 and tensile strength did not change significantly for the same 6 wt % NCC composites. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44683.
Nonlinear MPC Controller Design for AIR Supply of PEM Fuel Cell Based Power Systems
Authors: Ouyang Quan , Chen Jian , Wang Fan , Su Hongye 
Published: November 2016

AbstractThe air supply system, which provides the oxygen for the fuel cell stack, is one of the most important subsystems of the proton exchange membrane fuel cell (PEMFC). In order to improve the performance of the air supply, a small rechargeable lithium‐ion battery is utilized to start up the PEMFC system and provide buffer power supply for the load demand. With energy consumption of the compressor considered, a power coordinating algorithm utilizing a virtual potential field approach is presented to manage the power demand for the PEMFC and the battery while maintaining the battery's state of charge. A nonlinear observer is designed to estimate the unmeasurable states of the air supply system and its convergence is proven. A nonlinear MPC method is proposed to control the air flow and ensure the adequate oxygen supply. Simulation results are provided to validate the performance of the power management algorithm and the air supply control method. Compared with the results of the MPC algorithm and the nonlinear MPC method for the PEMFC system without an auxiliary battery, the method designed here has better performance.
Transformation of Free and Dipeptide‐Bound Glycated Amino Acids by Two Strains of Saccharomyces cerevisiae
Authors: Hellwig Michael , Börner Marie , Beer Falco , van Pée Karl‐Heinz , Henle Thomas 
Published: November 2016

AbstractThe yeast Saccharomyces cerevisiae transforms branched‐chain and aromatic amino acids into higher alcohols in the Ehrlich pathway. During microbiological culturing and industrial fermentations, this yeast is confronted with amino acids modified by reducing sugars in the Maillard reaction (glycation). In order to gain some preliminary insight into the physiological “handling” of glycated amino acids by yeasts, individual Maillard reaction products (MRPs: fructosyllysine, carboxymethyllysine, pyrraline, formyline, maltosine, methylglyoxal‐derived hydroimidazolone) were administered to two strains of S. cerevisiae in a rich medium. Only formyline was converted into the corresponding α‐hydroxy acid, to a small extent (10 %). Dipeptide‐bound pyrraline and maltosine were removed from the medium with concomitant emergence of several metabolites. Pyrraline was mainly converted into the corresponding Ehrlich alcohol (20–60 %) and maltosine into the corresponding α‐hydroxy acid (40–60 %). Five specific metabolites of glycated amino acids were synthesized and characterized. We show for the first time that S. cerevisiae can use glycated amino acids as a nitrogen source and transform them into new metabolites, provided that the substances can be transported across the cell membrane.
Multicenter midterm follow‐up results using the gore septal occluder for atrial septal defect closure in pediatric patients
Authors: Grohmann Jochen , Wildberg Christian , Zartner Peter , Abu‐Tair Tariq , Tarusinov Gleb , Kitzmüller Erwin , Schmoor Claudia , Stiller Brigitte , Kampmann Christoph 
Published: November 2016

ObjectivesTo assess the safety and efficacy of the Gore Septal Occluder (GSO) used for device‐closure of significant secundum‐type atrial septal defects (ASD II) focusing on pediatric patients.BackgroundThe GSO is a patch‐like double disc device. Due to its design, it is assumed to be safe, even when implanted in ASDs with deficient retro‐aortic rims.MethodsMulticenter retrospective analysis of consecutive children and adolescents with a GSO in situ for at least 12 months according to a 1‐ to 4‐year midterm follow‐up.ResultsHundred and seventy three pediatric patients were enrolled. At implantation, median age was 6 years (range 0.7–17.9), median body weight and length were 21 kg (6.4–95) and 119 cm (65–193). Median follow‐up period was 20 months (range 12–51). ASD anatomy was comprised of single defects in 131 patients (76%), multi‐fenestrated defects in 42 (24%), and deficient retro‐aortic rims in 33 (19%). Follow‐up confirmed an overall closure‐rate of 95.4%. Small residual shunts were reported in eight patients (4.6%) without need for any re‐intervention. Complications were classified as minor events both during the initial procedure (9 patients, 5.2%) and on follow‐up (another 9 patients), including transient AV block II in three patients (1.8%) and four snare‐retrievals (2.4%) during the initial procedure.ConclusionsPeriprocedural and midterm follow‐up data have shown the GSO to be effective and safe for ASD device closure in children and adolescents. GSO may be considered the first‐choice device in deficient retro‐aortic rims and multi‐fenestrated defects, when covering most of the atrial septum is necessary. © 2016 Wiley Periodicals, Inc.
Revealing Germylene Compounds to Attain Superbasicity with Sigma Donor Substituents: A Density Functional Theory Study
Authors: Biswas Abul Kalam , Ganguly Bishwajit 
Published: November 2016

AbstractCompounds of GeII are shown for the first time to function as superbases. Two B(N=PiPr3)2 groups attached to a germanium(II) center show a gas‐phase proton affinity of 296.2 kcal mol−1, which is close to the range of a hyperbase as revealed by B3LYP‐D3/6‐31G(2d,p) level of theory. These DFT calculations showed better agreement of geometrical parameters for the reported stable germylene compound 1 than previously reported calculations. A systematic study with different substitutions of GeII revealed that such a system can achieve basicity close to a hyperbase. The stabilities of these superbases were examined with dimerization energy and singlet–triplet state energy difference (ΔES–T). Furthermore, the calculated gas‐phase proton affinity values also show good correlation with the most negative valued point (Vmin) in electron‐rich regions from the molecular electrostatic potential. The high PA values of compounds were also supported by ionization potential, electron affinity, absolute electronegativity, and absolute hardness calculations. The energetics for the reaction with BH3 and AlMe3 further suggest that the lone pair of GeII can act as a Lewis base and display higher donor–acceptor bond strengths.
Solid‐phase extraction with metal–organic frameworks for the analysis of chiral compounds
Authors: Tang Bo , Zhang Jun‐Hui , Zi Min , Chen Xue‐Xian , Yuan Li‐Ming 
Published: November 2016

AbstractMetal–organic frameworks (MOFs) are excellent porous materials with nanoscale cavities and high surface areas, which make them promising as novel adsorbents in solid‐phase extraction (SPE). In this article we report a new application of the chiral MOF [Zn2(D‐Cam)2(4,4′‐bpy)]n in SPE used for the measurement of the enantiomeric excess (ee) of (±)‐1,1′‐bi‐2‐naphthol. Several important experimental parameters that may influence the extraction efficiency were investigated and optimized. Under the optimum conditions, a good linearity (R2 > 0.999) was found between the ee value and the reciprocal of the peak areas. When compared with the actual ee measured using chiral HPLC, the SPE‐based assay also showed good accuracy and precision. The results showed that SPE based on chiral MOFs as adsorbents is a simple and effective method for the determination of the ee values of chiral compounds.
Selective Synthesis of Cyclic Carbonate by Salalen–Aluminum Complexes and Mechanistic Studies
Authors: Cozzolino Mariachiara , Rosen Tomer , Goldberg Israel , Mazzeo Mina , Lamberti Marina 
Published: November 2016

AbstractSalalen–aluminum complexes were synthesized and used as catalysts in the reactions of CO2 with different epoxides. The reaction of cyclohexene oxide and CO2 was thoroughly investigated. In particular, the effect of the reaction conditions (nature and equivalents of the co‐catalyst, CO2 pressure, and temperature) and of the ligands (substituents on the ancillary ligand, nature of the labile ligand, and nature of the nitrogen‐donor atoms) on the results of this reaction was studied. The cycloaddition reaction of CO2 with terminal epoxides bearing different functional groups was realized. Moreover, NMR mechanistic studies provided information on the catalytic cycle. Interestingly, the characterization of an intermediate species in the mechanism of the reaction of cyclohexene oxide with CO2, catalyzed by one of the salalen–aluminum complexes, was accomplished.