bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification of prototypes from Ligustri Lucidi Fructus in rat plasma based on a data‐dependent acquisition and multicomponent pharmacokinetic study
Authors: Wang Yucheng , Feng Keyu , Li Mengrong , Han Lifeng , Wang Weiqiang , Si Dandan , Chen Xiaopeng , Yang Wenzhi , Gao Xiumei , Liu Erwei
Published: March 2020

The identification and quantization of traditional Chinese medicine (TCM) are a challenge for researchers and industry. Using untargeted analytical methods, the in vivo detection and identification of TCM compounds are difficult because of the significant interference of endogenous substances. Fortunately, the ongoing development of new analytical technologies, especially Q‐Orbitrap–MS, offers some solutions. Our team developed a holistic MS method, combining untargeted data‐dependent MS2 (dd‐MS2) modes to extensively identify TCM prototypes in vivo. The method was successfully applied to the analysis of Ligustri Lucidi Fructus (LLF). LLF is a widely used TCM with a remarkable nourishing effect on the liver and kidney. In the study, we aimed to identify the prototypes in rat plasma after oral administration of LLF extract. Following separation on an HSS T3 column, LLF extract and rat plasma were performed in untargeted dd‐MS2 mode. Forty‐seven compounds were characterized in rats plasma as prototypes of LLF extract. Furthermore, seven major prototypes were chosen as pharmacokinetic markers to investigate LLF's pharmacokinetic properties. The results provides comprehensive determination of compounds in LLF both in vitro and in vivo, which is important for quality control, pharmacology studies and clinical use of LLF.
Distribution of Nitrogen‐Fixation Genes in Prokaryotes Containing Alternative Nitrogenases
Authors: Addo Maame A. , Dos Santos Patricia C.
Published: March 2020

Biological nitrogen fixation is an inherent trait exclusive to a select number of prokaryotes. Although molybdenum nitrogenase is the dominant catalyst for dinitrogen reduction, some diazotrophs also contain one or two additional types of nitrogenase that use alternative metal content as the active‐site cofactor. The occurrence of alternative nitrogenases has not been well studied due to the discriminatory expression of the molybdenum nitrogenase and lack of comprehensive genomic data. This study reports on the genomic analysis of 87 unique species containing alternative nitrogenase sequences. The distribution of nitrogen‐fixing genes within these species from distinct taxonomic groups shows the presence of the minimum gene set required for nitrogen fixation, including catalytic and biosynthetic enzymes of the Mo‐dependent system (NifHDKENB) and the varying occurrence of additional Nif‐dedicated components. These include NifS and NifU, found primarily in aerobic species, thus suggesting that these genes are necessary to accommodate the high demand for Fe−S clusters during aerobic nitrogen fixation.
Retorting Photocorrosion and Enhanced Charge Carrier Separation at CdSe Nanocapsules by Chemically Synthesized TiO2 Shell for Photocatalytic Hydrogen Fuel Generation
Authors: Rao Vempuluru Navakoteswara , Pitchaimuthu Sudhagar , Ravi Parnapalle , Sathish Marappan , Han Hyungkyu , Venkatakrishnan Shankar Muthukonda
Published: March 2020

Metal chalcogenide‐based semiconductor nanostructures are promising candidates for photocatalytic or photoelectrocatalytic hydrogen generation. In order to protect CdSe from photocorrosion, a layer of TiO2 wrapped (shell) onto CdSe (core) nanocapsule via the post‐synthesis process. The morphology studies confirm that a thin crystalline TiO2 shell (3–8 nm) wrapped in all the three directions onto CdSe core and thickness of the shell can be controlled through modulating the titania precursor concentration. The feasibility of pristine CdSe nanocapsules and CdSe@TiO2 in transforming visible light to hydrogen conversion was tested through photocatalysis reaction. The CdSe@TiO2 nanocapsules generated a four‐fold high rate of hydrogen gas (21 mmol.h−1.g−1cat) than pristine CdSe. In order to understand the role of shell@core, we have studied the photoelectrochemical and impedance analysis. The CdSe@TiO2 nanocapsules showed higher photoelectric current generation and lower charge transfer resistance at electrode/electrolyte interfaces compared to pristine CdSe. These studies endorse that chemically synthesized crystalline TiO2 shell played a multifunctional role in (a) surface passivation from photocorrosion, (b) promoting photocharge carrier separation via tunneling process between CdSe and TiO2 interface. As a result, CdSe@TiO2 nanocapsules showed a high conversion efficiency of 12.9 % under visible light irradiation (328 mW.cm−2) and a TOF of 0.05018 s−1.
Oligophenyls with Multiple Disulfide Bridges as Higher Homologues of Dibenzo[c,e][1,2]dithiin: Synthesis and Application in Lithium‐Ion Batteries
Authors: Sonnenschein Christoph , Ender Christopher P. , Wang Faxing , Schollmeyer Dieter , Feng Xinliang , Narita Akimitsu , Müllen Klaus
Published: March 2020

Higher homologues of dibenzo[c,e][1,2]dithiin were synthesized from oligophenyls bearing multiple methylthio groups. Single‐crystal X‐ray analyses revealed their nonplanar structures and helical enantiomers of higher meta‐congener 6. Such dibenzo[1,2]dithiin homologues are demonstrated to be applicable to lithium‐ion batteries as cathode, displaying a high capacity of 118 mAh g−1 at a current density of 50 mA g−1.
Conformation‐Dependent Response to the Protonation of Diphenanthrioctaphyrin(1.1.1.0.1.1.1.0): A Route to Pseudorotaxane‐Like Structures
Authors: Szyszko Bartosz , Przewoźnik Monika , Białek Michał J. , Białońska Agata , Chmielewski Piotr J. , Latos‐Grażyński Lechosław
Published: March 2020

Diphenanthrioctaphyrin(1.1.1.0.1.1.1.0), an expanded carbaporphyrinoid incorporating two phenanthrenylene moieties, exists as two separate, yet interconvertible, locked stereoisomers. These species demonstrate complex dynamic behavior upon protonation, consisting in multiple conformational rearrangements and anion‐binding events. The formation of one of the final dicationic forms is accompanied by the inclusion of a complex anion(s) within the macrocyclic cavity yielding a pseudorotaxane‐like host–guest complex. Protonation with trifluoroacetic or dichloroacetic acids followed by neutralization afforded a conformation‐switching cycle, which involves six structurally different species. Analogous acidification with chiral 10‐camphorsulfonic acid and subsequent neutralization generated one of the free base stereoisomers with enantiomeric excess. Therefore, it was shown that the simple acid‐base chemistry of diphenanthrioctaphyrin can act as stimulus, inducing chirality into the system, allowing for the manipulation of the stereochemical information imprinted into the enantiomers of the macrocycle.
Absolute stereochemical determination of 1,2‐diols via complexation with dinaphthyl borinic acid
Authors: Torabi Kohlbouni Saeedeh , Sarkar Aritra , Zhang Jun , Li Xiaoyong , Borhan Babak
Published: March 2020

Rapid derivatization of chiral 1,2‐diols with dinaphthyl borinic acid (DBA) leads to a cyclic boronate, enabling the absolute stereochemical prediction via exciton‐coupled circular dichroic (ECCD) of the naphthyl groups. Aryl‐ and alkyl‐substituted 1,2‐diols derivatized with DBA yield a predictable ECCD, which is also in agreement with theoretical predictions derived from computationally minimized structures.
Rohstoffinnovationen und Rohstoffeffizienz
Authors: Teipel Ulrich , Schweppe Rainer
Published: March 2020

No abstract.
Axially Chiral Aryl‐Alkene‐Indole Framework: A Nascent Member of the Atropisomeric Family and Its Catalytic Asymmetric Construction
Authors: Wang Cong‐Shuai , Li Tian‐Zhen , Liu Si‐Jia , Zhang Yu‐Chen , Deng Shuang , Jiao Yinchun , Shi Feng
Published: March 2020

Summary of main observation and conclusion

A new class of axially chiral aryl‐alkene‐indole frameworks have been designed, and the first catalytic asymmetric construction of such scaffolds has been established by the strategy of organocatalytic (Z/E)‐selective and enantioselective (4+3) cyclization of 3‐alkynyl‐2‐indolylmethanols with 2‐naphthols or phenols (all >95 : 5 E/Z, up to 98% yield, 97% ee). This reaction also represents the first catalytic asymmetric construction of axially chiral alkene‐heteroaryl scaffolds, which will add a new member to the atropisomeric family. This approach has not only confronted the great challenges in constructing axially chiral alkene‐heteroaryl scaffolds but also provided a powerful strategy for the enantioselective construction of axially chiral aryl‐alkene‐indole frameworks.
The Reaction of Sulfur Dioxide Radical Cation with Hydrogen and its Relevance in Solar Geoengineering Models
Authors: Satta Mauro , Cartoni Antonella , Catone Daniele , Castrovilli Mattea Carmen , Bolognesi Paola , Zema Nicola , Avaldi Lorenzo
Published: March 2020

SO2 has been proposed in solar geoengineering as a precursor of H2SO4 aerosol, a cooling agent active in the stratosphere to contrast climate change. Atmospheric ionization sources can ionize SO2 into excited states of
, which quickly reacts with trace gases in the stratosphere. In this work we explore the reaction of
with
excited by tunable synchrotron radiation, leading to
(
), where H contributes to O3 depletion and OH formation. Density Functional Theory and Variational Transition State Theory have been used to investigate the dynamics of the title barrierless and exothermic reaction. The present results suggest that solar geoengineering models should test the reactivity of
with major trace gases in the stratosphere, such as H2 since this is a relevant channel for the OH formation during the nighttime when there is not OH production by sunlight. OH oxides SO2, triggering the chemical reactions leading to H2SO4 aerosol.
Hydrogen Evolution Reaction by Atomic Layer‐Deposited MoNx on Porous Carbon Substrates: The Effects of Porosity and Annealing on Catalyst Activity and Stability
Authors: Ramesh Rahul , Sawant Sandesh Y. , Nandi Dip K. , Kim Tae Hyun , Kim Deok Hyun , Han Seung‐Min , Jang Yujin , Ha Myoung Gyu , Cho Moo Hwan , Yoon Taeho , Kim Soo‐Hyun
Published: March 2020

Molybdenum‐based compounds are considered as a potential replacement for expensive precious‐metal electrocatalysts for the hydrogen evolution reaction (HER) in acid electrolytes. However, coating of thin films of molybdenum nitride or carbide on a large‐area self‐standing substrate with high precision is still challenging. Here, MoNx is uniformly coated on carbon cloth (CC) and nitrogen‐doped carbon (NC)‐modified CC (NCCC) substrates by atomic layer deposition (ALD). The as‐deposited film has a nanocrystalline character close to amorphous and a composition of approximately Mo2N with significant oxygen contamination, mainly at the surface. Among the as‐prepared ALD‐MoNx electrodes, the MoNx/NCCC has the highest HER activity (overpotential η≈236 mV to achieve 10 mA cm−2) owing to the high surface area and porosity of the NCCC substrate. However, the durability of the electrode is poor, owing to the poor adhesion of NC powder on CC. Annealing MoNx/NCCC in H2 atmosphere at 400 °C improves both the activity and durability of the electrode without significant change in the phase or porosity. Annealing at an elevated temperature of 600 °C results in formation of a Mo2C phase that further enhances the activity (η≈196 mV to achieve 10 mA cm−2), although there is a huge reduction in the porosity of the electrode as a consequence of the annealing. The structure of the electrode is also systematically investigated by electrochemical impedance spectroscopy (EIS). A deviation in the conventional Warburg impedance is observed in EIS of the NCCC‐based electrode and is ascribed to the change in the H+ ion diffusion characteristics, owing to the geometry of the pores. The change in porous nature with annealing and the loss in porosity are reflected in the EIS of H+ ion diffusion observed at high‐frequency. The current work establishes a better understanding of the importance of various parameters for a highly active HER electrode and will help the development of a commercial electrode for HER using the ALD technique.
Short‐Time Hydrothermal Treatment of Poplar Wood for the Production of a Lignin‐Derived Polyphenol Antioxidant
Authors: Zhang Tongtong , Zhou Hao , Fu Yingjuan , Zhao Yingjie , Yuan Zaiwu , Shao Zhiyong , Wang Zhaojiang , Qin Menghua
Published: March 2020

Artificial antioxidants are synthesized from fossil sources and are now widely used in the polymer, food, and cosmetics industries. The gradual depletion of fossil resources makes it practically significant and necessary to produce green antioxidants from renewable lignocellulosic resources. Herein, short‐time hydrothermal (STH) treatment was developed for production of lignin‐derived polyphenol antioxidants (LPAs) from poplar wood under conditions of high temperature and high pressure. LPA yields from 21.5 to 37.6 % on the basis of lignin in untreated wood were obtained by STH treatments as result of lignin depolymerization at 190–200 °C and 10 MPa in 5–8 min. Depolymerization reactions were confirmed by the much lower molecular weight of LPA (1076 g mol−1) than that of native lignin (4094 g mol−1). NMR spectroscopy revealed the structural features of lignin in the isolated LPA, namely syringyl and guaiacyl units with well‐preserved interunit linkages. A Folin–Ciocalteu assay indicated that each LPA molecule contained 5.4 phenolic hydroxyl groups on average, much more than other technical lignins. The remarkable antioxidant ability of LPA was verified by the radical‐scavenging index of 53.5–67.3, much higher than 0.2–11.1 of the commercial antioxidants butylated hydroxytoluene (BHT) and butylated hydroxyanisole (BHA). STH treatment only requires water and heat for production of high‐value antioxidant, which provides a green and sustainable method for the utilization of lignocelluloses.
Using the otolith sulcus to aid in prey identification and improve estimates of prey size in diet studies of a piscivorous predator
Authors: Byrd Barbie L. , Hohn Aleta A. , Krause Jacob R.
Published: March 2020

Diet studies are fundamental for understanding trophic connections in marine ecosystems. In the southeastern US, the common bottlenose dolphin Tursiops truncatus is the predominant marine mammal in coastal waters, but its role as a top predator has received little attention. Diet studies of piscivorous predators, like bottlenose dolphins, start with assessing prey otoliths recovered from stomachs or feces, but digestive erosion hampers species identification and underestimates fish weight (FW). To compensate, FW is often estimated from the least affected otoliths and scaled to other otoliths, which also introduces bias. The sulcus, an otolith surface feature, has a species‐specific shape of its ostium and caudal extents, which is within the otolith edge for some species. We explored whether the sulcus could improve species identification and estimation of prey size using a case study of four sciaenid species targeted by fisheries and bottlenose dolphins in North Carolina. Methods were assessed first on otoliths from a reference collection (n = 421) and applied to prey otoliths (n = 5,308) recovered from 120 stomachs of dead stranded dolphins. We demonstrated in reference‐collection otoliths that cauda to sulcus length (CL:SL) could discriminate between spotted seatrout (Cynoscion nebulosus) and weakfish (Cynoscion regalis) (classification accuracy = 0.98). This method confirmed for the first time predation of spotted seatrout by bottlenose dolphins in North Carolina. Using predictive models developed from reference‐collection otoliths, we provided evidence that digestion affects otolith length more than sulcus or cauda length, making the latter better predictors. Lastly, we explored scenarios of calculating total consumed biomass across degrees of digestion. A suggested approach was for the least digested otoliths to be scaled to other otoliths iteratively from within the same stomach, month, or season as samples allow. Using the otolith sulcus helped overcome challenges of species identification and fish size estimation, indicating their potential use in other diet studies.
Stable Ferromagnetic Crystal of Two‐Dimensional Manganese‐Chromium Oxalate with Supramolecular Cation
Authors: Kubo Kazuya , Yoshitake Masashi , Hoshino Norihisa , Noro Shin‐ichiro , Akutagawa Tomoyuki , Nakamura Takayoshi
Published: March 2020

A supramolecular cation of (m‐FAni+)(tst‐DCH[18]crown‐6), where m‐FAni+ and tst‐DCH[18]crown‐6 denote m‐fluoroanilinium and trans‐syn‐trans‐dicyclohexano[18]crown‐6, respectively, was introduced into a ferromagnetic {[MnIICrIII(oxalate)3]–} layer to obtain a stable organic‐inorganic hybridized crystal. The crystal structure of (m‐FAni+)(tst‐DCH[18]crown‐6){[MnIICrIII(oxalate)3]–} was constructed by alternate stacking of a two‐dimensional honeycomb layer of {[MnIICrIII(oxalate)3]–} and the supramolecular cations. Cyclohexyl moieties of tst‐DCH[18]crown‐6 penetrated the pores of the honeycomb layers, excluding solvent molecules in the crystal. The anionic layers showed ferromagnetic order of MnII and CrIII ions with S = 5/2 and S = 3/2 spins, respectively, at 5.5 K. Although the m‐FAni+ showed disorder with respect to 180° rotation of the aryl ring, no significant anomaly was observed in the dielectric response, suggesting that the disorder is static.
A Microporous MOF with Inorganic Nitrate Ions Immobilized on a Porous Surface Displaying Efficient C2H2 Separation and Purification
Authors: Gao Xiaoxia , Zhong Haoyan , Zhang Yingying , Yao Yongna , Chen De‐li , He Yabing
Published: March 2020

A microporous MOF based on a heterotopic ligand was successfully synthesized under solvothermal conditions and fully characterized using single‐crystal and powder X‐ray diffraction, TGA, FTIR, and microanalyses. Single‐crystal X‐ray diffraction analyses showed that the title MOF contains rich inorganic nitrate ions decorating the channel surface that can serve as C2H2 recognition sites. Its selective gas adsorption properties towards C2H2 over CO2 and CH4 were evaluated by single‐component equilibrium adsorption measurements and IAST calculations, establishing its promising potential for C2H2 separation and purification. At ambient conditions, the C2H2 uptake capacity reaches 92.2 cm3 (STP) g–1, while the IAST‐predicted adsorption selectivities are up to 30.6 and 4.5 for the equimolar C2H2‐CH4 and C2H2‐CO2 binary gas mixtures, respectively. Furthermore, DFT computation studies revealed that the inorganic nitrate ion plays a very important role for preferential adsorption of C2H2 over CO2 and CH4.
Magnesiated and Calciated N‐Mesityl Diphenylphosphinic Amides
Authors: Schönherr Paul R. W. , Hempel Niklas A. , Görls Helmar , Krieck Sven , Westerhausen Matthias
Published: March 2020

Metalation of N‐mesityl‐P,P‐diphenylphosphinic amide (1) in THF at room temperature with MgBu2 and [(thf)2Ca{N(SiMe3)2}2] yields [(thf)nM{Ph2P(=O)–N–Mes}2{Ph2P(=O)–NH–Mes}2] [M/n = Mg/0 (2), Ca/2 (3)] regardless of the applied stoichiometry. These complexes are stabilized by weak intramolecular N–H···N hydrogen bridges. In both complexes only one NMR signal set is observed, however, for the magnesium complex 2 the 1H NMR chemical shift of the hydrogen bridge shifts toward higher field with increasing temperature. For the calcium congener 3 two resonance sets are observed at low temperature, allowing to determine an energy barrier of 52.4 kJ mol–1 for the proton exchange between adjacent nitrogen bases.
Heteroatom Bridged Tetrathiafulvalenes
Authors: Avarvari Narcis
Published: March 2020

Tetrathiafulvalene (TTF) derivatives are the most representative electroactive precursors for the preparation of crystalline conducting materials. The occurrence of mixed valence states, through electron delocalization, as well as strong intermolecular interactions, are important prerequisites to account for the high electronic conduction in the solid state and the dimensionality of the material. In this respect, the modulation of through space or through bond intramolecular electron communication can be efficiently achieved in heteroatom bridged bis(TTF) derivatives. Moreover, the bridging heteroatoms can engage, depending on their nature, in intermolecular interactions in the solid state. In this Minireview, we focus on flexible and rigid bis(TTF) derivatives formulated as X(TTF)2 and X2(TTF)2 (X = Si, Ge, Sn, P, Sb, S, Se, Te) thus containing one or two bridges in ortho position. A special attention is given to the solid‐state structures of these precursors and their oxidized species, their electrochemical behavior, reactivity, role of the heteroatom in the establishment of intramolecular mixed valence and intermolecular interactions, and the conducting properties.
H2O2 Screening from Saliva of Gum Diseased‐patient through CN‐dot Wrapped Cu2O Nano‐frogspawns Ionic Liquid Nanocomposite
Authors: Hayat Khizar , Hassan Akhtar Mahmood , Siddique Saleemi Awais , Badaruddin Ahmad Hafiz , Akhtar Naeem
Published: March 2020

Herein, we report the development of a robust, sensitive, and selective non‐enzymatic electrochemical sensor for the detection of hydrogen peroxide (H2O2). The novel BA modified CN‐dot wrapped Cu2O‐nano‐frogspawn (FS@CN‐dot) sensor probe demonstrated a catalytic property towards H2O2 that allowed the highly sensitive electrochemical detection at a low reduction potential. The as prepared CN‐dot wrapped Cu2O hetero‐structured nanocomposite was analyzed using surface analysis methods to confirm the morphology, crystallinity, and oxidation states of various constituents and dopant elements. Further, the morphological analysis of the Cu2O nanoparticles revealed that the Cu2O retains frogspawns‐liked structure. Under the optimized experimental conditions, the sensor showed a wide dynamic range of H2O2 from 0.5 μM to 9 mM with a detection limit (LD) of 1.2±0.1 nM. The designed sensing probe showed good stability, high sensitivity, and selectivity even in the presence of potential interfering molecules. To check the reliability of the fabricated sensor in biomedical applications, the proposed sensing probe was successfully applied to monitor H2O2 in saliva of a gum‐diseased patient. To the best of our knowledge, this report is the first of its kind not only because of its novel construction style in terms of CN source, but also in terms of real sample applicability as well.
Spectral graph theory of brain oscillations
Authors: Raj Ashish , Cai Chang , Xie Xihe , Palacios Eva , Owen Julia , Mukherjee Pratik , Nagarajan Srikantan
Published: March 2020

The relationship between the brain's structural wiring and the functional patterns of neural activity is of fundamental interest in computational neuroscience. We examine a hierarchical, linear graph spectral model of brain activity at mesoscopic and macroscopic scales. The model formulation yields an elegant closed‐form solution for the structure–function problem, specified by the graph spectrum of the structural connectome's Laplacian, with simple, universal rules of dynamics specified by a minimal set of global parameters. The resulting parsimonious and analytical solution stands in contrast to complex numerical simulations of high dimensional coupled nonlinear neural field models. This spectral graph model accurately predicts spatial and spectral features of neural oscillatory activity across the brain and was successful in simultaneously reproducing empirically observed spatial and spectral patterns of alpha‐band (8–12 Hz) and beta‐band (15–30 Hz) activity estimated from source localized magnetoencephalography (MEG). This spectral graph model demonstrates that certain brain oscillations are emergent properties of the graph structure of the structural connectome and provides important insights towards understanding the fundamental relationship between network topology and macroscopic whole‐brain dynamics. .
Palbinone alleviates diabetic retinopathy in STZ‐induced rats by inhibiting NLRP3 inflammatory activity
Authors: Shi Qiang , Wang Jianchao , Cheng Yuhong , Dong Xiaomin , Zhang Ming , Pei Cheng
Published: March 2020

Diabetic retinopathy (DR) is the primary cause of blindness and visual impairment in diabetes patients worldwide. However, laser and surgical therapies at DR have short‐term effectiveness and cause side effects. Treatment with natural products is a reasonable alternative treatment for DR. The main objective of this investigation is to explore the efficacy of a bioactive compound such as palbinone (PB) in DR. Experimental rats were injected intraperitoneally with streptozotocin (STZ, 65 mg/kg), and these established experimental rats were treated with PB (20 mg/kg/bw) for 42 days. The observed results showed that PB considerably reduced the proinflammatory cytokine (interleukin‐18 [IL‐18] and IL‐1β) production as well as improved the activities of antioxidant enzymes (superoxide dismutase, catalase, and glutathione peroxidase) particularly in the retinal region of STZ‐induced DR rats. In addition, PB treatment improved nuclear factor erythroid 2‐related factor 2 (Nrf2) accumulation and enhanced the heme oxygenase‐1 expression, and major antioxidants downregulated Nrf2 in the damaged retina. Also, the expression levels of nod‐like receptor family pyrin domain containing 3 (NLRP3), cleaved‐caspase‐1, IL‐1β, and apoptosis‐associated speck‐like protein containing CARD in the retinal region were notably upregulated in STZ‐induced DR, which was eliminated by PB interference. PB administration exerted efficient antioxidant activities, Nrf2 pathway activation, and inhibition of NLRP3 inflammasome. This current investigation concluded that PB considerably reduced the retinal inflammation and oxidative stress stimulated via high glucose, and also activated the antioxidative Nrf2 pathway and inhibited the NLRP3 inflammasome formation in rats.
In the presence of Trypanosoma cruzi antigens, activated peripheral T lymphocytes retained in the liver induce a proinflammatory phenotypic and functional shift in intrahepatic T lymphocyte
Authors: Meuser-Batista Marcelo , Vacani-Martins Natalia , Cascabulho Cynthia Machado , Beghini Daniela Gois , Henriques-Pons Andrea
Published: March 2020

In secondary lymphoid organs, pathogen-derived and endogenous danger molecules are recognized by pattern recognition receptors, leading to adaptive proinflammatory immune responses. This conceptual rule does not apply directly to the liver, as hepatic immune cells tolerate gut-derived bacterial molecules from the flora. Therefore, the recognition of danger and proinflammatory stimuli differs between the periphery and the liver. However, the tolerant nature of the liver must be overcome in the case of infections or cancer, for example. The central paradigm is the basis for danger recognition and the balance between inflammation and tolerance in the liver. Here, we observed functional integration, with activated peripheral T lymphocytes playing a role in the induction of a proinflammatory environment in the liver in the presence of Trypanosoma cruzi antigens. When only parasite extract was orally administered, it led to the up-regulation of hepatic tolerance markers, but oral treatment plus adoptively transferred activated splenic T lymphocytes led to a proinflammatory response. Moreover, treated/recipient mice showed increased levels of TNF, IFN-γ, IL-6, and CCL2 in the liver and increased numbers of effector and/or effector memory T lymphocytes and F4/80+ cells. There was a reduction in FoxP3+ Treg cells, NKT cells, and γδ T lymphocytes with increased liver damage in the presence of activated peripheral T cells. Our results show that the induction of a proinflammatory liver response against T. cruzi danger molecules is at least partially dependent on cooperation with activated peripheral T cells.
Attenuation of allergen-mediated mast cell activation by rosemary extract (Rosmarinus officinalisL.)
Authors: Yousef Michael , Crozier Robert W.E. , Hicks Natalie J. , Watson Colton J.F. , Boyd Tylar , Tsiani Evangelia , MacNeil Adam J.
Published: March 2020

Mast cells are immune sentinels and a driving force in both normal and pathological contexts of inflammation, with a prominent role in allergic hypersensitivities. Crosslinking of FcεRI by allergen-bound IgE Abs leads to mast cell degranulation, resulting in an early-phase response and release of newly synthesized pro-inflammatory mediators in the late-phase. The MAPK and NF-κB pathways are established as critical intracellular mechanisms directing mast cell-induced inflammation. Rosemary extract (RE) has been shown to modulate the MAPK and NF-κB pathways in other cellular contexts in vitro and in vivo. However, the effect of RE on mast cell activation has not been explored, and thus we aim to evaluate the potential of RE in modulating mast cell activation and FcεRI/c-kit signaling, potentially via these key pathways. Primary murine mast cells were sensitized with anti-TNP IgE and stimulated with cognate allergen (TNP-BSA) under stem cell factor (SCF) potentiation while treated with 0–25 µg/ml RE. RE treatment inhibited phosphorylation of p38 and JNK MAPKs while also impairing NF-кB transcription factor activity. Gene expression and mediator secretion analysis showed that RE treatment decreased IL-6, TNF, IL-13, CCL1, and CCL3, but major component polyphenols do not contribute to these effects. Importantly, RE treatment significantly inhibited early phase mast cell degranulation (down to 15% of control), with carnosic acid and carnosol contributing. These findings indicate that RE is capable of modulating mast cell functional outcomes and that further investigation of the underlying mechanisms and its potential therapeutic properties in allergic inflammatory conditions is warranted.
Autoimmune responses and inflammation in type 2 diabetes
Authors: Prasad Mukul , Chen Elijah W. , Toh Sue-Anne , Gascoigne Nicholas R. J.
Published: March 2020

Obesity-induced insulin resistance is one of the largest noncommunicable disease epidemics that we are facing at the moment. Changes in lifestyle and greater availability of low nutritional value, high caloric food has led to the highest rates of obesity in history. Obesity impacts the immune system and obesity-associated inflammation contributes to metabolic diseases, such as type 2 diabetes. Both the adaptive and the innate immune system play a role in the regulation of glycemic control, and there is a need to understand how metabolic imbalances drive disease pathogenesis. This review discusses the cell types, mediators, and pathways that contribute to immunologic–metabolic crosstalk and explores how the immune system might be targeted as a strategy to treat metabolic disease.
Neutrophils at the crossroads of innate and adaptive immunity
Authors: Rosales Carlos
Published: March 2020

Neutrophils are the most abundant leukocytes in blood. From the circulation, they are quickly mobilized to sites of inflammation and/or infection. At the affected tissues, neutrophils display an impressive array of antimicrobial functions, including degranulation, production of reactive oxygen species (ROS), phagocytosis, and formation of neutrophil extracellular traps (NET). Because neutrophils are the first type of leukocytes to arrive at affected tissues and display potent microbicidal functions, they have been classically viewed as the first line of defense. In this view, neutrophils only destroy invading pathogens and then quietly die at the site of infection. However, in the last decade it has become increasingly evident that neutrophils are much more complex cells having not only effector functions in the innate immune response, but also the capacity of modulating the adaptive immune response, via direct interaction with, or by producing cytokines that affect dendritic cells and lymphocytes. In addition, neutrophil heterogeneity with clear different functional phenotypes has been recently described particularly in cancer and inflammation. This review provides an overview on the life of a neutrophil describing its beginnings, lifespan, and their principal functions in innate and adaptive immunity. Also, neutrophil heterogeneity and our current understanding of neutrophil contributions to health and disease are discussed.
Characterization of additives in plastics: From MS to MS10 multistep mass analysis and theoretical calculations of tris(2,4‐di‐tert‐butylphenyl)phosphate
Authors: Giorgi Gianluca , Bellani Lorenza , Giorgetti Lucia
Published: March 2020

In the analysis by electrospray (+) of an extract of hemp sprouts put in a polypropylene vial, we found a large contamination of a plastic additive. It was characterized by multiple‐stage MSn experiments (MS ÷ MS10) and identified as tris(2,4‐di‐tert‐butylphenyl)phosphate, also known with the synonyms F32IRS6B46, oxidized Naugard 524, and others. The MS2 ÷ MS7 spectra are characterized by consecutive eliminations of six isobutene molecules from the tert‐butyl moieties, some of them also occurring in the ion source. The first three are calculated to occur preferentially from the ortho positions, whereas eliminations from the para positions are estimated to be less favored at about 5–6 kcal/mol in each step. Once the first three isobutene molecules are eliminated, the remaining three are lost from the tert‐butyl moieties in para positions (MS5 ÷ MS7), yielding protonated triphenylphosphate, whose structure has been confirmed by the MS2 spectrum of triphenylphosphate standard: the latter spectrum is almost superimposable with the MS8 spectrum of the analyte under investigation. MS8 and MS9 spectra show main losses of water and C6H4 molecules. The MS10 spectrum of precursor ions at m/z 215 shows the gas‐phase addition of water and methanol and ions at m/z 168, attributable to the loss of a phosphorus oxide radical. Density functional theory (DFT) calculations (Becke 3LYP [B3LYP] 6‐311+G(2d,2p)) have been used to evaluate structure and stability of different ionic and neutral species involved in the decomposition pathways and to calculate thermochemical data of the decomposition reactions. This multistep mass analysis combined with theoretical calculations resulted to be particularly useful and effective, yielding chemical, thermochemical, and mechanistic data of significant utility in the structural characterization and identification of the unknown analyte as well as to define its gas‐phase reactivity under a multistep low‐energy collision‐induced dissociation regime.
New evidence for the intentional use of calomel as a white pigment
Authors: Crippa Mila , Legnaioli Stefano , Kimbriel Christine , Ricciardi Paola
Published: March 2020

In this work, we report the results of the in situ application of micro‐Raman spectroscopy to the analysis of two historic painted objects: a 15th‐century illuminated manuscript and a late 16th‐century portrait miniature. Both objects were unexpectedly found to contain calomel (Hg2Cl2), intentionally used as a white pigment. Calomel was a widespread and popular medicine until it fell out of use at the end of the 19th century due to its toxicity, and a material called ‘mercury white’ is referred to in 16th‐century technical literature on painting. However, although calomel has been recognised in the past as a degradation product of cinnabar in both wall and easel paintings, its deliberate use as a pigment on cultural heritage objects has only been documented recently in white areas painted on 17th‐century South American objects. The present study describes the first ever verified use of calomel as a white pigment on European works of art, both of which predate its documented use in South America.
Sturm's operator acting on vector valued K‐types
Authors: Maurischat Kathrin
Published: March 2020

We define Sturm's operator for vector valued Siegel modular forms obtaining an explicit description of their holomorphic projection in case of large absolute weight. However, for small absolute weight, Sturm's operator produces phantom terms in addition. This confirms our earlier results for scalar Siegel modular forms.
A Phase 2a Trial Investigating the Safety and Tolerability of the Novel Cortical Enhancer IRL752 in Parkinson's Disease Dementia
Authors: Svenningsson Per , Odin Per , Dizdar Nil , Johansson Anders , Grigoriou Sotirios , Tsitsi Panagiota , Wictorin Klas , Bergquist Filip , Nyholm Dag , Rinne Juha , Hansson Fredrik , Sonesson Clas , Tedroff Joakim ,   for the IRL752 Collaborators
Published: March 2020

Background

IRL752 is a novel small‐molecule compound that acts to regioselectively enhance norepinephrine, dopamine, and acetylcholine neurotransmission in the cerebral cortex.

Objective

The primary objective of the trial was to investigate the safety and tolerability of IRL752 in patients with Parkinson's disease and dementia.

Methods

Patients with Parkinson's disease and dementia were randomized to IRL752 or placebo treatment (3:1 ratio) for 28 days. The study drug was given as an adjunct treatment to the patients’ regular stable antiparkinsonian medication. Dosing was individually titrated for 14 days after which the dose was kept stable for an additional 14 days.

Results

A total of 32 patients were randomized to treatment, and 29 patients completed the 4‐week treatment. Adverse events were generally mild and transient and were mostly reported during the dose titration phase. There were 2 serious adverse events, and none of them were related to the experimental treatment. The average dose achieved in the stable dose phase was 600 mg daily, yielding a 2‐hour postdose plasma concentration of about 4 μM on day 28. Exploratory assessment of secondary outcomes indicated efficacy for symptoms and signs known to be poorly responsive to levodopa.

Conclusions

IRL752 appears to be safe and well tolerated for a 4‐week treatment in patients with Parkinson's disease and dementia. © 2020 International Parkinson and Movement Disorder Society
Impact of ultrasonography on identifying noninvasive prenatal screening false‐negative aneuploidy
Authors: Li Wei , Zeng Fanwei , Fan Baitong , Yu Nan , Wu Jing , Yang Yun , Huang Hui , Li Sheng‐li , Peng Zhiyu
Published: March 2020

Background

To evaluate the impact of ultrasonography on identifying noninvasive prenatal screening (NIPS) false‐negative aneuploidy.

Methods

Analysis of large population‐based NIPS false‐negative aneuploidy data comprising karyotypes, clinical outcomes, and ultrasound results.

Results

From December 2010 to July 2018, a total of 3,320,457 pregnancies were screened by NIPS performed in BGI; among them, 69 NIPS false‐negative aneuploidy cases with informed consent were confirmed, and ultrasound examination data for 48 cases were not available. Of the 21 cases with ultrasound results, 19 (90.5%) had various abnormalities on ultrasound, and two (9.5%) cases were shown to be normal on ultrasound. Additionally, six of seven live‐born fetuses (approximately 85.7%) were found to have abnormalities on ultrasound. Ventricular septal defects constituted the most frequently observed ultrasound abnormality type among the 21 NIPS false‐negative aneuploidy cases.

Conclusion

Application of NIPS has increased rapidly worldwide and now accounts for a large proportion of prenatal screening tests in China. This study suggests that ISUOG guideline should be followed practically, and structural abnormal ultrasound findings should not be neglected, even when NIPS produces a negative result. Combining NIPS with an ultrasound examination can further reduce the incidence of live births with aneuploidy.
Cheminformatics Analysis of Natural Product Scaffolds: Comparison of Scaffolds Produced by Animals, Plants, Fungi and Bacteria
Authors: Ertl Peter , Schuhmann Tim
Published: March 2020

Natural products (NPs) have evolved over a very long natural selection process to form optimal interactions with biologically relevant macromolecules. NPs are therefore a very useful source of inspiration for the design of new drugs. In the present study we report the results of a cheminformatics analysis of a large database of NP structures focusing on their scaffolds. First, general differences between NP scaffolds and scaffolds from synthetic molecules are discussed, followed by a comparison of the properties of scaffolds produced by different types of organisms. Scaffolds produced by plants are the most complex and those produced by bacteria differ in many structural features from scaffolds produced by other organisms. The results presented here may be used as a guidance in selection of scaffolds for the design of novel NP‐like bioactive structures or NP‐inspired libraries.
High gain broadband stacked triangular microstrip antennas
Authors: Chopra Rinkee , Kumar Girish
Published: March 2020

A low cost, broadband, and high gain stacked equilateral triangular microstrip antenna (ETMSA) is designed to cover the frequency band from 1700 to 2600 MHz with low cross polar level (X‐pol). The antenna consists of a metallic ETMSA at the bottom layer and three parasitically coupled ETMSAs (1B3T) are printed symmetrically on the bottom side of the top FR‐4 substrate layer, which is supported by foam inserted between the top and bottom layers. The bottom patch is shorted by a metallic via at its center. It improves the X‐pol in upper frequency band. The 1B3T ETMSA is further enclosed in a metallic cavity to improve the gain and front to back ratio (F/B). The fabricated 1B3T ETMSA provides 42.2% BW with peak gain of 10.8 dBi, F/B of more than 15.8 dB and X‐pol of less than −13.6 dB throughout the BW. The proposed antenna can be used for RF energy harvesting in 2G, 3G, 4G, and Wi‐Fi frequency bands.
Microwave imaging of breast cancer with factorization method: SPIONs as contrast agent
Authors: Coşğun Sema , Bilgin Egemen , Çayören Mehmet
Published: March 2020

Female breast at macroscopic scale is a nonmagnetic medium, which eliminates the possibility of realizing microwave imaging of the breast cancer based on magnetic permeability variations. However, by administering functionalized, superparamagnetic iron oxide nanoparticles (SPIONs) as a contrast material to modulate magnetic permeability of cancer cells, a small variation on the scattered electric field from the breast is achievable under an external, polarizing magnetic field.

Purpose

We demonstrate an imaging technique that can locate cancerous tumors inside the breast due to electric field variations caused by SPION tracers under different magnetic field intensities. Furthermore, we assess the feasibility of SPION‐enhanced microwave imaging for breast cancer with simulations performed on a multi‐static imaging configuration.

Methods

The imaging procedure is realized as the factorization method of qualitative inverse scattering theory, which is essentially a shape retrieval algorithm for inaccessible objects. The formulation is heuristically modified to accommodate the scattering parameters instead of the electric field to comply with the requirements of experimental microwave imaging systems.

Results

With full‐wave electromagnetic simulations performed on an anthropomorphically realistic breast phantom, which is excited with a cylindrical imaging prototype of 18 dipole antenna arranged as a single row, the technique is able to locate cancerous tumors for a experimentally achievable doses.

Conclusions

The technique generates nonanatomic microwave images, which map the cancerous tumors depending on the concentration of SPION tracers, to aid the diagnosis of the breast cancer.
Cooperativity in alkane‐1,2‐ and 1,3‐polyols: NMR, QTAIM, and IQA study of O─H…OH and C─H…OH bonding interactions
Authors: Lomas John S.
Published: March 2020

Proton nuclear magnetic resonance chemical shifts and atom–atom interaction energies for alkanepolyols with 1,2‐diol and 1,3‐diol repeat units, and for their 1:1 pyridine complexes, are computed by density functional theory calculations. In the 1,3‐polyols, based on a tG'Gg' repeat unit, the only important intramolecular hydrogen bonding interactions are O─H…OH. By quantum theory of atoms in molecules analysis of the electron density, unstable bond and ring critical points are found for such interactions in 1,2‐polyols with tG'g repeat units, from butane‐1,2,3,4‐tetrol onwards and in their pyridine complexes from propane‐1,2,3‐triol onwards. Several features (OH proton shifts and charges, and interaction energies computed by the interacting quantum atoms approach) are used to monitor the dependence of cooperativity on chain length: This is much less regular in 1,2‐polyols than in 1,3‐polyols and by most criteria has a higher damping factor. Well defined C─H…OH interactions are found in butane‐1,2,3,4‐tetrol and higher members of the 1,2‐polyol series, as well as in their pyridine complexes: There is no evidence for cooperativity with O─H…OH bonding. For the 1,2‐polyols, there is a tenuous empirical relationship between the existence of a bond critical point for O─H…OH hydrogen bonding and the interaction energies of competing exchange channels, but the primary/secondary ratio is always less than unity.
Untargeted metabolomic profiling of accessory sex gland fluid from Morada Nova rams
Authors: Sousa Solange D. , Lucini Luigi , Ajmone‐Marsan Paolo , van Tilburg Maurício F. , Moura Arlindo A.
Published: March 2020

The present study was conducted to characterize the metabolome of accessory gland fluid (AGF) of locally adapted Morada Nova rams, raised in the Brazilian Northeast. AGF was collected by an artificial vagina from five vasectomized rams. Metabolites were identified by gas chromatography‐mass spectrometry (GC/MS) and high‐performance liquid chromatography‐mass spectrometry (LC/MS), with the support of Human Metabolome Database, PubChem, LIPID Metabolites, Pathways Strategy databases, and MetaboAnalyst platforms. There were 182 and 190 metabolites detected by GC/MS and LC/MS, respectively, with an overlap of one molecule. Lipids and lipid‐like molecules were the most abundant class of metabolites in the ram AGF (127 compounds), followed by amino acids, peptides, and analogs(103 metabolites). Considering all GC/MS and LC/MS, fructose, glycerol, citric acid, d‐mannitol, d‐glucose, and l‐(+)‐lactic acid were the most abundant single metabolites present in the ram AGF. Meaningful pathways associated with AGF metabolites included glycine, serine and threonine metabolism; pantothenate and CoA biosynthesis; galactose metabolism; glutamate metabolism and phenylalanine metabolism, and so forth. In conclusion, the combined use of LC/MS and GC/MS was essential for getting a holistic view of the compounds embedded in the ram AGF. Chemical analysis of the accessory sex gland secretion is relevant for understanding sperm function and fertilization.
Factors associated with discharge opioid prescription after hip fracture fixation
Authors: Fandino Luis B. , Bhashyam Abhiram , Harris Mitchel B. , Zhang Dafang
Published: March 2020

Objective

Opioid prescribing after hip fracture fixation is variable, but the factors that drive this prescribing variation are not well‐described. The purpose of this study was to determine independent factors associated with increased opioid prescription upon discharge after hip fracture fixation.

Methods

A retrospective cohort study of 296 adult patients who underwent hip fracture fixation between January 2016 and December 2017 at two Level I trauma centers were included in our study. The primary outcome measurement was opioid prescription at discharge in morphine milligram equivalents (MME). Bivariate analysis was used to screen for factors, and multivariable regression analysis was used to identify independent factors associated with opioid prescription upon discharge from the hospital.

Results

Discharge opioid prescription amounts were available for 280 out of 296 patients (95%). The mean (±standard deviation) discharge opioid prescription was 212 (±319) MME. Multivariable regression analysis showed that younger age (p = 0.004), diabetes mellitus (p = 0.02), smoking (p < 0.001), treatment at hospital #2 (p < 0.001), and weekend discharge (p = 0.03) were associated with increased opioid prescription at discharge.

Conclusions

Increased opioid prescribing after hip fracture fixation is associated with patient‐ and system‐related factors. Prescriber education programs, prescription guidelines, and safe handoff practices that focus on these factors may help to decrease prescription variability and opioid overprescription across institutions.