bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lipid Heterogeneity between Astrocytes and Neurons Revealed by Single‐Cell MALDI‐MS Combined with Immunocytochemical Classification
Authors: Neumann Elizabeth K. , Comi Troy J. , Rubakhin Stanislav S. , Sweedler Jonathan V. 
Published: February 2019

AbstractTranscriptomics characterizes cells based on their potential molecular repertoire whereas direct mass spectrometry (MS) provides information on the actual compounds present within cells. Single‐cell matrix‐assisted laser desorption/ionization (MALDI) MS can measure the chemical contents of individual cells but spectra are difficult to correlate to conventional cell types, limiting the metabolic information obtained. We present a protocol that combines MALDI‐MS with immunocytochemistry to assay over a thousand individual rat brain cells. The approach entwines the wealth of knowledge obtained by immunocytochemical profiling with mass spectral information on the predominant lipids within each cell. While many lipid species showed a high degree of similarity between neurons and astrocytes, seventeen significantly differed between the two cell types, including four phosphatidylethanolamines elevated in astrocytes and nine phosphatidylcholines in neurons.
Selective [5,5]‐Sigmatropic Rearrangement by Assembly of Aryl Sulfoxides with Allyl Nitriles
Authors: Zhang Lei , He Jia‐Ni , Liang Yuchen , Hu Mengjie , Shang Li , Huang Xin , Kong Lichun , Wang Zhi‐Xiang , Peng Bo 
Published: February 2019

AbstractAromatic [5,5]‐sigmatropic rearrangement is an appealing protocol for accessing 1,4‐substituted arenes. However, such a protocol has not been well utilized in organic synthesis because of the difficulties in the synthesis of the substrates, selectivity issues, and limited substrate scope. Described herein is a new [5,5]‐sigmatropic reaction utilizing readily available aryl sulfoxides and allyl nitriles. This reaction features mild reaction conditions, high chemo‐ and regioselectivity, excellent functional‐group compatibility, and broad substrate scope. Computational studies suggest that the success of the reaction can be attributed to the selective electrophilic assembly of the rearrangement precursors, in which a linear ‐C=C=N‐ linkage favors [5,5]‐sigmatropic rearrangement over the competitive [3,3]‐sigmatropic rearrangement.
Engineering Polymer‐Binding Bispecific Antibodies for Enhanced Pretargeted Delivery of Nanoparticles to Mucus‐Covered Epithelium
Authors: Huckaby Justin T. , Parker Christina L. , Jacobs Tim M. , Schaefer Alison , Wadsworth Daniel , Nguyen Alexander , Wang Anting , Newby Jay , Lai Samuel K. 
Published: February 2019

AbstractMucus represents a major barrier to sustained and targeted drug delivery to mucosal epithelium. Ideal drug carriers should not only rapidly diffuse across mucus, but also bind the epithelium. Unfortunately, ligand‐conjugated particles often exhibit poor penetration across mucus. In this work, we explored a two‐step “pretargeting” approach through engineering a bispecific antibody that binds both cell‐surface ICAM‐1 and polyethylene glycol (PEG) on the surface of nanoparticles, thereby effectively decoupling cell targeting from particle design and formulation. When tested in a mucus‐coated Caco‐2 culture model that mimics the physiological process of mucus clearance, pretargeting increased the amount of PEGylated particles binding to cells by around 2‐fold or more compared to either non‐targeted or actively targeted PEGylated particles. Pretargeting also markedly enhanced particle retention in mouse intestinal tissues. Our work underscores pretargeting as a promising strategy to improve the delivery of therapeutics to mucosal surfaces.
4,4′‐Diaponeurosporene‐Producing Bacillus subtilis Promotes the Development of the Mucosal Immune System of the Piglet Gut
Authors: Jing Yuchao , Liu Haofei , Xu Wenwen , Yang Qian 
Published: February 2019

ABSTRACTGut mucosal immune responses are known to act as the first line of defense against invasion of pathogenic microorganisms. Piglets have an incompletely developed gut mucosal immune system, making them sensitive to intestinal infections. Promoting the development of the mucosal immune system will increase the pathogen resistance of piglets. The aim of the present study was to investigate the effect of carotenoid (4,4′‐diaponeurosporene)‐producing Bacillus subtilis (B.s‐Dia) on intestinal mucosal immunity in piglets. We showed that oral administration to piglets of B.s‐Dia remarkably improved the development of Peyer's patches (PPs) (P < 0.01), and increased villus height (P < 0.01) and colon crypt depth (P < 0.01). In addition, B.s‐Dia also increased the number of intraepithelial lymphocytes (P < 0.01), while Bacillus subtilis (B.s) had no significant influence on it (P > 0.05). Moreover, B.s‐Dia also increased the number of SIgA+ cells (P < 0.01). Oral administration of either B.s or B.s‐Dia increased the number of CD4+ and CD8+ cells in ileum lamina propria (P < 0.01). These results indicate that B.s‐Dia contributes to a higher extent to porcine mucosal immune system development than B.s, and might serve as an immunopotentiator candidate. Anat Rec, 302:1800–1807, 2019. © 2019 American Association for Anatomy
Three‐Dimensional Geometric Morphometric Analysis of Treeshrew (Scandentia) Lower Molars: Insight into Dental Variation and Systematics
Authors: Selig Keegan R. , Sargis Eric J. , Silcox Mary T. 
Published: February 2019

ABSTRACTScandentia (treeshrews) is an order of small‐bodied Indomalayan mammals generally agreed to be a member of Euarchonta with Primates and Dermoptera (colugos). However, intraordinal relationships among treeshrews are less well understood. Although recent studies have begun to clarify treeshrew taxonomy using morphological and molecular datasets, previous analysis of treeshrew dentition has yielded little clarity in terms of species‐level relationships within the order. However, these studies made use of character‐based methods, scoring traits across the dental arcade, which depend on there being clear differences among taxa that can be encapsulated in coding schemes. Geometric morphometrics has the potential to capture subtler shape variation, so it may be better for examining similarities among closely related taxa whose teeth have a similar bauplan. We used three‐dimensional geometric morphometrics on a sample of treeshrew lower second molars and compared the patterns of variation to the results of previous studies. We captured 19 landmarks on a sample of 43 specimens representing 15 species. Using specimen‐based principal components analysis and between‐group principal component analysis, the two treeshrew families (Tupaiidae and Ptilocercidae) were well separated in morphospace. Moreover, several treeshrew species plot in morphospace according to the clades established in previous molecular work, with closely related species plotting closer to one another than to more distantly related species, suggesting that dental morphology can be useful when studying relationships among treeshrews. As most extinct treeshrews are known only from teeth, understanding morphological patterns in treeshrew molars is important for future work on the evolutionary history of Scandentia. Anat Rec, 302:1154–1168, 2019. © 2019 Wiley Periodicals, Inc.
Photostability of quantum dot micelles under ultraviolet irradiation
Authors: Chinnathambi Shanmugavel , Hanagata Nobutaka 
Published: February 2019

AbstractPhospholipid quantum dot micelles are useful for bio‐applications because of their amphiphilicity and exceptional biocompatibilities. We investigated the uptake of phospholipid [polyethylene glycol (PEG), biotin, and folic acid terminated] modified CdSe/ZnS quantum dot micelles by cancer cells and its photostability under ultrviolet light in the C spectrum (UV‐C) (254 nm) or UV‐A (365 nm) light irradiation. The stability of micelles to the exposure of UV‐C and UV‐A light was assessed. Biotin‐modified quantum dot micelles give photoluminescence enhancement under UV‐C light irradiation. Folate modified micelle under UV‐C and UV‐A results show considerable photoluminescence enhancement. Photoluminescence lifetime measurements showed 7.04, 8.11 and 11.42 ns for PEG, folate, and biotin terminated phospholipid micelles, respectively. Folate and biotin‐modified quantum dot micelles showed excellent uptake by HeLa cells under fluorescence confocal microscopy. Phospholipid CdSe/ZnS quantum dot micelles can be potentially used for diagnosis and treatment of cancer in the future.
Tandem Cell‐Free Protein Synthesis as a Tool for Rapid Screening of Optimal Molecular Chaperones
Authors: Yang Hyeon‐Jung , Lee Kyung‐Ho , Lim Hye Jin , Kim Dong‐Myung 
Published: February 2019

A simple and flexible method is developed for rapid screening of molecular chaperones that enhance the functional expression of recombinant proteins. A panel of molecular chaperones are transiently expressed in a reaction mixture of cell‐free protein synthesis and then a target protein is subsequently expressed in the presence of these presynthesized molecular chaperones. The biological activity of the cell‐free synthesized target protein is compared to identify the effective molecular chaperones. This strategy successfully identifies individual and combinations of bacterial molecular chaperones that markedly improved the functional expression of horseradish peroxidase. The authors believe that the presented strategy provides a versatile platform for the optimal production of functional proteins, and can also be extended to studies of other interacting proteins.
Sesquiterpenes from the Leaves ofMagnolia delavayiFranch. and Their Cytotoxic Activities
Authors: Xie Zhang‐Qiao , Ding Lin‐Fen , Wang De‐Sheng , Nie Wei , Liu Jiang‐Xin , Qin Jing , Song Liu‐Dong , Wu Xing‐De , Zhao Qin‐Shi 
Published: February 2019

AbstractThirteen sesquiterpenes including eight new ones, magnodelavins A−H (1–8), were obtained from the 95 % ethanolic extract of the leaves ofMagnolia delavayiFranch. The structures of the new compounds were determined by exhaustive1H‐,13C‐, 2D‐NMR, UV, IR, and HR‐ESI‐MS data, as well as X‐ray crystallographic analysis. Compounds9and10showed potent cytotoxic activities against HL‐60, A‐549, SMMC‐7721, MCF‐7, and SW480 human cancer cell lines in vitro using MTS assay.
Convergent Cascade Catalyzed by Monooxygenase–Alcohol Dehydrogenase Fusion Applied in Organic Media
Authors: Huang Lei , Aalbers Friso S. , Tang Wei , Röllig Robert , Fraaije Marco W. , Kara Selin 
Published: February 2019

AbstractWith the aim of applying redox‐neutral cascade reactions in organic media, fusions of a type II flavin‐containing monooxygenase (FMO‐E) and horse liver alcohol dehydrogenase (HLADH) were designed. The enzyme orientation and expression vector were found to influence the overall fusion enzyme activity. The resulting bifunctional enzyme retained the catalytic properties of both individual enzymes. The lyophilized cell‐free extract containing the bifunctional enzyme was applied for the convergent cascade reaction consisting of cyclobutanone and butane‐1,4‐diol in different microaqueous media with only 5 % (v/v) aqueous buffer without any addition of external cofactor. Methyl tert‐butyl ether and cyclopentyl methyl ether were found to be the best organic media for the synthesis of γ‐butyrolactone, resulting in about 27 % analytical yield.
Development of Trityl Group Anchored Solubilizing Tags for Peptide and Protein Synthesis
Authors: Yoshiya Taku , Tsuda Shugo , Masuda Shun 
Published: February 2019

AbstractRecently, solubilizing tag methods (Trt‐K and Trt‐R method) were developed for the challenging synthesis of peptides/proteins by means of native chemical ligation. In this system, the solubilizing tag can be attached to the Cys side chain by simply mixing the tag‐introducing reagent under acidic conditions. The tagged peptides/proteins exhibited high water solubility thanks to the introduction of redundant oligo‐Lys/Arg. In the final reaction, the tag can be quickly and cleanly detached by a standard deprotection reaction with trifluoroacetic acid. Herein, the development and application of these methods are described.
Phenazine Antibiotic‐Inspired Discovery of Bacterial Biofilm‐Eradicating Agents
Authors: Huigens Robert W. , Abouelhassan Yasmeen , Yang Hongfen 
Published: February 2019

AbstractBacterial biofilms are surface‐attached communities of slow‐growing and non‐replicating persister cells that demonstrate high levels of antibiotic tolerance. Biofilms occur in nearly 80 % of infections and present unique challenges to our current arsenal of antibiotic therapies, all of which were initially discovered for their abilities to target rapidly dividing, free‐floating planktonic bacteria. Bacterial biofilms are credited as the underlying cause of chronic and recurring bacterial infections. Innovative approaches are required to identify new small molecules that operate through bacterial growth‐independent mechanisms to effectively eradicate biofilms. One source of inspiration comes from within the lungs of young cystic fibrosis (CF) patients, who often endure persistent Staphylococcus aureus infections. As these CF patients age, Pseudomonas aeruginosa co‐infects the lungs and utilizes phenazine antibiotics to eradicate the established S. aureus infection. Our group has taken a special interest in this microbial competition strategy and we are investigating the potential of phenazine antibiotic‐inspired compounds and synthetic analogues thereof to eradicate persistent bacterial biofilms. To discover new biofilm‐eradicating agents, we have established an interdisciplinary research program involving synthetic medicinal chemistry, microbiology and molecular biology. From these efforts, we have identified a series of halogenated phenazines (HPs) that potently eradicate bacterial biofilms, and future work aims to translate these preliminary findings into ground‐breaking clinical advances for the treatment of persistent biofilm infections.
Nanocomposite scaffold seeded with mesenchymal stem cells for bone repair
Authors: Farshadi Maryam , Johari Behrooz , Erfani Ezadyar Elham , Gholipourmalekabadi Mazaher , Azami Mahmoud , Madanchi Hamid , Haramshahi Seyed Mohammad Amin , Yari Abazar , Karimizade Ayoob , Nekouian Reza , Samadikuchaksaraei Ali 
Published: February 2019

AbstractThe mechanical property of bone tissue scaffolds is one of the most important aspects in bone tissue engineering that has remained problematic. In our previous study, we fabricated a three‐dimensional scaffold from nano‐hydroxyapatite/gelatin (nHA/Gel) and investigated its efficiency in promoting bone regeneration both in vitro and in vivo. In the present study, the effect of adding silicon carbide (SiC) on the mechanical and biological behaviors of the nHA/Gel/SiC and bone regeneration in vivo were determined. nHA and SiC were synthesized and characterized by the X‐ray diffraction pattern and transmission electron microscope image. Layer solvent casting, freeze drying, and lamination techniques were applied to prepare these scaffolds. Then, the biocompatibility and cell adhesion behavior of the synthesized nHA/Gel/SiC scaffolds were investigated. For in vivo studies, rats were categorized into three groups: blank defect, blank scaffold, and rat bone marrow mesenchymal stem cells (rBM‐MSCs)/scaffold. After 1, 4, and 12 weeks post‐injury, the rats were sacrificed and the calvaria were harvested. Sections with a thickness of 5 µm thickness were prepared and stained with hematoxylin–eosin and Masson's Trichrome, and immunohistochemistry was performed. Our results showed that SiC effectively increased the mechanical properties of the nHA/Gel/SiC scaffold. No significant differences were observed in biocompatibility, cell adhesion, and cytotoxicity of the nHA/Gel/SiC in comparison with the nHA/Gel nanocomposite. Based on histological and immunohistochemical studies, both osteogenesis and collagenization were significantly higher in the rBM‐MSCs/scaffold group, quantitatively and qualitatively. The present study strongly suggests the potential of SiC as an alternative strategy to improve the mechanical and biological properties of bone tissue engineering scaffolds, and shows that the pre‐seeded nHA/Gel/SiC scaffold with rBM‐MSCs improves osteogenesis in the engineered bone implant.
Titanocene‐Catalyzed Sequential Carbocarboxylation of Dienes and Alkenes with Organic Halides and Carbon Dioxide in the Presence of nBuMgCl
Authors: Hang Wei , Zou Song , Xi Chanjuan 
Published: February 2019

AbstractA titanocene‐catalyzed regioselective carbocarboxylation of dienes or alkenes has been developed. This reaction proceeds efficiently to form flexible and versatile carboxylic acids in the presence of nBuMgCl by the combined use of dienes or alkenes with organic halides and CO2 as the carbon synthon and carboxyl group, respectively. 2,3‐Disubstituted 1,3‐butadienes were used to afford acrylic acids in excellent yields with various organic halides. In the most cases, the arylalkenes afforded benzylic acids in high yields under similar conditions. The titanocene catalyst plays important roles in the generation of radicals and allyl‐ or benzyl‐magnesium halides.
CuS and Cu2S as Cathode Materials for Lithium Batteries: A Review
Authors: Jiang Kyle , Chen Zonghai , Meng Xiangbo 
Published: February 2019

AbstractNowadays, lithium‐ion batteries (LIBs) take a very important role for energy storage. LIBs are dominant in consumer electronics, and they have also entered the market of hybrid electric vehicles (HEVs), plug‐in HEVs, and pure EVs. However, state‐of‐the‐art LIBs are electrochemically intercalation‐based and are still limited in energy density and power rates. To address these challenges and others (e. g. safety issues and cost), conversion‐based copper sulfides (CuxS, 1≤x≤2) have been investigated as alternative cathodes for improved electrochemical performance, that is, higher energy density, better cycling stability, and enhanced rate capability. In this work, we summarize the recent research progress on CuxS to gain a better understanding of the material's electrochemical mechanisms and develop feasible strategies for improving its performance.
Rhodium Phosphide: A New Type of Hydrogen Oxidation Reaction Catalyst with Non‐Linear Correlated Catalytic Response to pH
Authors: Yang Fulin , Bao Xi , Gong Dan , Su Lixin , Cheng Gongzhen , Chen Shengli , Luo Wei 
Published: February 2019

AbstractRh2P nanoparticles were colloidally synthesized and used as electrocatalysts toward the hydrogen oxidation reaction (HOR) in alkaline electrolyte for the first time. It was found that Rh2P exhibits remarkable catalytic performance, which is superior to Rh and even commercial Pt/C and can be attributed to the synergistic effect caused by the P atoms on the surface of Rh2P. This work might open up a new avenue for expanding the family of electrocatalysts with advanced HOR performance in alkaline electrolyte.
Guests Like Gear Levers: Donor Binding to Coordinatively Unsaturated Metal Sites in MIL‐101 Controls the Linker′s Rotation
Authors: Khudozhitkov Alexander E. , Arzumanov Sergey S. , Kolokolov Daniil I. , Kholdeeva Oxana A. , Freude Dieter , Stepanov Alexander G. 
Published: February 2019

AbstractWe present investigation of the effect of electron‐donor guests on framework mobility in the metal–organic framework (MOF) MIL‐101(Cr) monitored by solid state 2H NMR spectroscopy. In a guest‐free material, the mobile phenylene fragments of the terephthalate (TP) linkers populate two fractions with notably different kinetic parameters for torsional motion. Two fractions of rotational motion are indicative of non‐equivalence of TP linker binding to the Cr3O trimer, the primary building unit of the MIL‐101 framework. It is established that the interaction of the guest molecules with coordinatively unsaturated metal sites (CUS) of the MOF dramatically decreases torsional barriers for the linker motions, enhancing the rotation rate. This result is opposite to a more conventional slowing down effect on the linker rotation of the guests not selectively interacting with the adsorption sites inside the framework of the MOFs. The effect of coordination on both the torsional barrier and the rotation rate depends notably on the particular guest interacting with the CUS. The found effects of the guest on the rotational motion represent a basis for developing the strategy for ruling and controlling the linker rotation in MOFs with CUS. It is shown that if water occupies CUS, another guest (tert‐butanol, cyclohexanone) fails to competitively coordinate to the site.
Exponential Molecular Amplification by H2O2‐Mediated Autocatalytic Deprotection of Boronic Ester Probes to Redox Cyclers
Authors: Pallu Justine , Rabin Charlie , Creste Geordie , Branca Mathieu , Mavré François , Limoges Benoît 
Published: February 2019

AbstractHerein, a new molecular autocatalytic reaction scheme based on a H2O2‐mediated deprotection of a boronate ester probe into a redox cycling compound is described, generating an exponential signal gain in the presence of O2 and a reducing agent or enzyme. For such a purpose, new chemosensing probes built around a naphthoquinone/naphthohydroquinone redox‐active core, masked by a self‐immolative boronic ester protecting group, were designed. With these probes, typical autocatalytic kinetic traces with characteristic lags and exponential phases were obtained by using either UV/Visible or fluorescence optical detection, or by using electrochemical monitoring. Detection of concentrations as low as 0.5 μm H2O2 and 0.5 nm of a naphthoquinone derivative were achieved in a relatively short time (<1 h). From kinetic analysis of the two cross‐activated catalytic loops associated with the autocatalysis, the key parameters governing the autocatalytic reaction network were determined, indirectly showing that the analytical performances are currently limited by the slow nonspecific self‐deprotection of boronate probes. Collectively, the present results demonstrate the potential of this new exponential molecular amplification strategy, which, owing to its generic nature and modularity, is quite promising for coupling to a wide range of bioassays involving H2O2 or redox cycling compounds, or for use as a new building block in the development of more complex chemical reaction networks.
Heterogeneous Modeling Approach for Gas‐Limited Reactions in an Inclined Rotating Fixed Bed Reactor
Authors: Timaeus Robert , Hampel Uwe , Schubert Markus 
Published: February 2019

AbstractA heterogeneous modeling approach for an inclined rotating fixed bed reactor with concentric internal tube is introduced. The novel reactor is designed to intensify the mass transfer of gas‐limited heterogeneous catalyzed reactions by intermittent catalyst wetting, which is enabled exposing the packed bed to rotation and inclination. A simulation study for the hydrogenation of α‐methylstyrene is presented. In particular, the influence of period length and different wetting‐draining cycles on the space‐time yield of the reactor is analyzed.
Innovation in Knowledge Intensive Business Services (KIBS)
Authors: Doloreux David , Frigon Anthony 
Published: February 2019

AbstractThis article examines the determinants of innovation in knowledge intensive business services (KIBS), generally hypothesizing that differences in the effect of the determinants of innovation depend on the type of innovation developed within KIBS. The study results are based on estimates of two econometric models using data from a survey of 392 firms in the province of Ontario, Canada. © 2019 ASAC. Published by John Wiley & Sons, Ltd.