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A novel squaramide cage (2) binds H2PO4− and HP2O73− with high selectivity and affinity in a highly polar protic solvent system. Receptor 2 is also able to extract these hydrophilic anions into a chloroform phase from water. The X-ray crystal structure demonstrated that compound 2 forms a complex with H2PO4− with 1 : 1 stoichiometry in the solid state. [ABSTRACT FROM AUTHOR]

Introduction: Ultrasonography has been used in the medical field for more than 50 years and estimated to be safe. The aim of the study was to set the criteria for the diagnosis of fetal asphyxia depending on the indices of fetal middle cerebral artery (FMCA) and umbilical artery (UA). Subjects and Methods: Color Doppler ultrasound (ALOKA-SSD1700) was used to confirm the dynamics of blood flow indices in fetal arteries. Among 417 pregnant women (327 normal and 90 with fetal distress), various arterial velocimetric parameters (ratio of systole to diastole and pulsatility and resistance indexes) were evaluated in the FMCA and UA. t-test and Chi-square test were used for the comparison of average and ratios, respectively, and Ridit test for grading of data. Results: The normal values of blood flow indices of FMCA with gestational age in normal pregnancy reached their peak at the 30th week and then gradually decreased. As for funicular artery, the indices reached their peak at the 28th week and then gradually decreased. The criterion for the diagnosis of fetal asphyxia depending on the blood flow of FMCA and UA is the ratio of resistance indices in the MCA or UA 10, and the sensitivity, specificity, and accuracy of diagnosis were 86.7%, 98.8%, and 96.2%, respectively. Conclusion: The study confirmed the normal values and dynamics of the blood flow indices of FMCA and UA according to the number of weeks of normal pregnancy and determined criteria for the diagnosis of fetal asphyxia depending on those indices. [ABSTRACT FROM AUTHOR]

Transient receptor potential ankyrin 1 (TRPA1), a cold receptor in sensory neurons activated by a variety of stimuli, is implicated in nociception and mechanotransduction. To help understand the vesicular glutamate transporter (VGLUT)-mediated glutamate signaling in TRPA1-immunopositive (+) neurons, we examined the expression of VGLUT1 and VGLUT2 in the TRPA1+ neurons in the male rat trigeminal ganglion (n = 19) under normal conditions and following experimental inflammation in the vibrissal pad by light microscopic immunohistochemistry (n = 11), western blot (n = 8), and quantitative analysis. One half (50.8%, 250/492) of the TRPA1+ neurons expressed VGLUT2, and a small fraction (8.3%, 57/683) also expressed VGLUT1. The majority of the VGLUT2-expressing TRPA1+ (VGLUT2+/TRPA1+) neurons coexpressed the markers of peptidergic and non-peptidergic neurons, CGRP, IB4, and TRPV1 but not the markers of neurons with myelinated fibers, NF200 and parvalbumin. In contrast, most VGLUT1+/TRPA1+ neurons coexpressed NF200 and parvalbumin but rarely expressed CGRP, IB4, or TRPV1. Following experimental inflammation, the fraction of VGLUT2+ (experimental vs. control: 34.7% vs. 22.3%), TRPA1+ (39.3% vs. 25.3%), and VGLUT2+/TRPA1+ (60.7% vs. 49.7%) neurons and the protein levels for TRPA1 and VGLUT2 increased significantly, compared to control, whereas the fraction of VGLUT1+ and VGLUT1+/TRPA1+ neurons and the protein level for VGLUT1 remained unchanged. These findings suggest that both VGLUT1 and VGLUT2 are involved in the glutamate signaling in TRPA1+ neurons under normal conditions in the male rats, and raise a possibility that VGLUT2 may play a role in the TRPA1-induced hypersensitivity following inflammation. [ABSTRACT FROM AUTHOR]

A strapped calix[4]pyrrole (2) with a fluorogenic pyrene unit linked to the rigid strap via the methylene bridge has been synthesised. It was established by1H NMR and fluorescence spectroscopic analyses and isothermal titration calorimetry (ITC) studies that receptor2is capable of binding the F−, Cl−,(ppi) andanions in organic media, with high selectivity for F−being observed relative to the other anions. Upon exposure to the F−and, the fluorescence of2is quenched, an effect ascribed to facilitated PET (photo-induced electron transfer) from the nitrogen atom to the pyrene moiety, which is induced by anion binding. In contrast, the fluorescence of2was enhanced upon treatment with the HSO4−anion as the result of the PET inhibition that results from nitrogen atom protonation. A single crystal X-ray structure of the chloride complex of2and the1H NMR spectral data revealed that the chloride anion is bound to the receptor via aliphatic C–H•••Cl−hydrogen bonds, as well as N–H•••Cl−interactions. [ABSTRACT FROM AUTHOR]

A calix[4]pyrrolestrapped by a bulky calix[4]arene diester lockedin its cone conformation has been prepared. On the basis of 1H NMR spectroscopic analyses carried out in CDCl3, itis concluded that this hybrid system, receptor 2, bindsonly the fluoride anion and does so with remarkably high affinityeven in the presence of an excess of various potentially competingenvironmentally and biologically ubiquitous anions (studied as thetetrabutylammonium, cesium, or lithium salts). Solid statestructural analyses provide support for the notion that receptor 2interacts well with the fluoride anion in the solid state. [ABSTRACT FROM AUTHOR]

Anion transporters based on small molecules have received attention as therapeutic agents because of their potential to disrupt cellular ion homeostasis. However, a direct correlation between a change in cellular chloride anion concentration and cytotoxicity has not been established for synthetic ion carriers. Here we show that two pyridine diamide-strapped calix[4]pyrroles induce coupled chloride anion and sodium cation transport in both liposomal models and cells, and promote cell death by increasing intracellular chloride and sodium ion concentrations. Removing either ion from the extracellular media or blocking natural sodium channels with amiloride prevents this effect. Cell experiments show that the ion transporters induce the sodium chloride influx, which leads to an increased concentration of reactive oxygen species, release of cytochrome c from the mitochondria and apoptosis via caspase activation. However, they do not activate the caspase-independent apoptotic pathway associated with the apoptosis-inducing factor. Ion transporters, therefore, represent an attractive approach for regulating cellular processes that are normally controlled tightly by homeostasis. [ABSTRACT FROM AUTHOR]

A new approach to the construction of self-assembled structures is reported that is based on ion-pair recognition. Towards this end, the calix[4]pyrrole naphthocrown-4 hybrid structures 2 and 3 were prepared. These multitopic receptors contain recognition sites for both anions and cations. On the basis of solution-phase 1H NMR spectroscopic analysis and solid-state single-crystal X-ray diffraction structural studies, it was established that receptors 2 and 3 are able to bind specific ion pairs with high selectivity via different binding modes. In the case of CsF and CsCl, the ion-pair complexes formed from receptors 2 and 3 were found to self-assemble to produce either linear supramolecular polymeric crystalline solids or nanotube-like cyclic hexamers depending on the specific choice of ion pairs and crystallization solvents. Proton NMR studies provided evidence for solution-phase self-association in organic media. [ABSTRACT FROM AUTHOR]

Ion pairreceptors, which are able to bind concurrentlyboth a cation and an anion, often display higher selectivity and affinityfor specific ion pairs than simple ion receptors capable of recognizingprimarily either a cation or an anion. This enhancement in recognitionfunction is attributable to direct or indirect cooperative interactionsbetween cobound ions via electrostatic attractions between oppositelycharged ions, as well as to positive allosteric effects. In addition,by virtue of binding the counterions of the targeted ion, ion pairreceptors can minimize the solvation of the counterions, which canotherwise have a negative effect on the interactions between the receptorsand the targeted ions. As a result of their more favorable interactions,ion pair receptors are attractive for use in applications, such asextraction and sensing, where control of the binding interactionsis advantageous. In this Account, we illustrate this potential inthe context of ion pair receptors based on the calix[4]pyrrole scaffold.Both simple ditopic ion pair receptors, containing sites for the recognitionof a single anion and single cation, and so-called multitopic ionpair receptors will be discussed. The latter systems differ from conventional,so-called ditopic ion pair receptors in that they contain more thanone binding site for a given targeted ion (e.g., a cation). This permitsa level of selectivity and control over binding function not normallyseen for simple ion or ion pair receptors containing one or two bindingsites, respectively. [ABSTRACT FROM AUTHOR]

This paper presents a nonparametric approach to failure detection of broken rotor bars in inverter-fed induction motors (IMs). We lay the mathematical foundation for a diagnostic model of a rotor bar fault that captures the rotor bar high-frequency (HF) characteristics. The model shows that the HF equivalent motor resistance can be used as a direct indicator of broken rotor bars. It should be emphasized that the proposed detection methodology is applicable to any shape of rotor slot design by incorporating the idea of synchronous reference frame based injection and by taking the HF resistance as the fault detector. The proposed detection technique is also insensitive to other motor parameters and is effective under arbitrary load conditions. The full time-domain-based signature process provides efficient detection and enhances fault isolation. The identification scheme was implemented and tested on an inverter-fed 1.5-kW IM. [ABSTRACT FROM AUTHOR]

Overexpression of phospholipase C-γγl (PLC-γγl) in rat 3Y1 fibroblasts leads to the formation of tumors in nude mice. However, the molecular mechanism for PLC-γγl-mediated cellular transformation has not been studied in detail. In this study, we found that glyceraldehyde-3-phosphate dehydrogenase (GAPDH), a glycolytic enzyme, protein levels were increased substantially in cells overexpressing PLC-γγl, and that PLC-γγl upregulation of GAPDH was due to a decrease in ubiquitination, followed by sustained protein turnover and subsequent accumulation. These observations suggest that regulation of the turnover rate of GAPDH is critical for anchorage-independent growth and ATP synthesis of transformed cells. [ABSTRACT FROM AUTHOR]

Compared with simple ion receptors, which are able to bind either a cation or an anion, ion pair receptors bearing both a cation and an anion recognition site offer the promise of binding ion pairs or pairs of ions strongly as the result of direct or indirect cooperative interactions between co-bound ions. This critical reviewfocuses on the recent progress in the design of ion pair receptors and summarizes the various binding modes that have been used to accommodate ion pairs (110 references). [ABSTRACT FROM AUTHOR]

Abstract: Neurofilaments (NFs) are heteropolymers composed of light (NF-L), middle (NF-M), and heavy (NF-H) subunits, present in most neurons. NF-L polymerizes on its own to provide a scaffold on which regular NFs form via the cross-bridging of NF-M or NF-H. To clarify the mechanism of regulation of NF-L self-assembly, we developed an assay using truncated mutant NF-L fused to glutathione-S transferase (GST). Western immunoblotting data show that the GST-fused head–rod domains of NF-L are necessary and sufficient for detecting assembled NF-L. The levels of self-assembled NF-L subunits detected using GST fusion proteins were consistent with those detected by electron microscopy and turbidity assay. Our results collectively imply that GST-fused head–rod domains of NF-L are critical tools for analyzing NF-L self-assembly in vitro. [Copyright &y& Elsevier]

Abstract: A new calix[4]crown chemosensor based on dual sensing probes reveals Pb2+ ion selectivity over other metal ions, which arises from a hypsochromic shift of azo units in UV spectrum as well as a fluorescence enhancement of pyrenyl parts in fluorescence spectrum via a suppressed FRET. [Copyright &y& Elsevier]

A simply prepared carbon nano tube paste electrode (CNTPE) was utilized for monitoring mercury ion concentration using the cyclic voltammetry (CV) method and the square wave anodic stripping voltammetric (SWASV) method. The CNTPE was compared with various conventional electrodes. The CNTPE method was applied to determine the concentration of trace levels of Hg(II) in several water samples, which yielded a relative error of 0.6% with a concentration of 0.20 mg L-1 Hg(II). It was deposited at -0.5 V (vs Ag/AgCl), which was subsequently reduced to +0.20 V to strip it on the CNTPE. The optimal experimental conditions for the analysis were found to be as follows: pH value of 4 for the medium; deposition potential of -0.5 V; deposition time of 210 s; SW frequency of 40 Hz; SW amplitude of 100 mV, and step potential of 25 mV. Given these optimum conditions, a linear range was observed within the concentrations of 1.0-25.0 µg L-1 and 40.0-200.0 µg L-1. The detection limit was found to be 0.42 µg L-1. [ABSTRACT FROM AUTHOR]

Phosphoinositide-specific phospholipase C-γ1 (PLC-γ1) has two pleckstrin homology (PH) domains, an N-terminal domain and a split PH domain. Here we show that pull down of NIH3T3 cell extracts with PLC-γ1 PH domain-glutathione S-transferase fusion proteins, followed by matrix-assisted laser desorption ionization-time of flight-mass spectrometry, identified β-tubulin as a binding protein of both PLC-γ1 PH domains. Tubulin is a main component of microtubules and mitotic spindle fibers, which are composed of α- and β-tubulin heterodimers in all eukaryotic cells. PLC-γ1 and β-tubulin colocalized in the perinuclear region in COS-7 cells and cotranslocated to the plasma membrane upon agonist stimulation. Membrane-targeted translocation of depolymerized tubulin by agonist stimulation was also supported by immunoprecipitation analyses. The phosphatidylinositol 4,5-bisphosphate (PIP2) hydrolyzing activity of PLC-γ1 was substantially increased in the presence of purified tubulin in vitro, whereas the activity was not promoted by bovine serum albumin, suggesting that β-tubulin activates PLC-γ1. Furthermore, indirect immunofluorescent microscopy showed that PLC-γ1 was highly concentrated in mitotic spindle fibers, suggesting that PLC-γ1 is involved in spindle fiber formation. The effect of PLC-γ1 in microtubule formation was assessed by overexpression and silencing PLC-γ1 in COS-7 cells, which resulted in altered microtubule dynamics in vivo. Cells overexpressing PLC-γ1 showed higher microtubule densities than controls, whereas PLC-γ1 silencing with small interfering RNAs led to decreased microtubule network densities as compared with control cells. Taken together, our results suggest that PLC-γ1 and β-tubulin transmodulate each other, i.e. that PLC-γ1 modulates microtubule assembly by β-tubulin, and β-tubulin promotes PLC-γ1 activity. [ABSTRACT FROM AUTHOR]

Metal ion complexation behavior in calix[4]crown multimers (mono, di, trimer) have been investigated through X-ray crystallography, two-phase extraction, and 1H NMR measurement. [Copyright &y& Elsevier]

Double- and multi-1,3-alternate-calixcrowns were prepared by multistep syntheses. [Copyright &y& Elsevier]

The multitopic ion-pair receptor 2 is able to recognize and extract various cesium and potassium salts via three different ion recognition modes. Furthermore, it is capable of extracting and then releasing KNO3via ion-pair metathesis with CsClO4, allowing KNO3 recovery. [ABSTRACT FROM AUTHOR]

Propolis is a natural resinous substance made by bees through mixing various plant sources. Propolis has been widely recognized as a functional food due to its diverse range of beneficial bioactivities. However, the therapeutic effects of consuming propolis against atopic dermatitis (AD) remain largely unknown. The current study aimed to investigate the potential efficacy of propolis against AD and explore the active compound as well as the direct molecular target. In HaCaT keratinocytes, propolis inhibited TNF‐α‐induced interleukin (IL)‐6 and IL‐8 secretion. It also led to a reduction in chemokines such as monocyte chemoattractant protein‐1 (MCP‐1) and macrophage‐derived chemokine (MDC), while restoring the levels of barrier proteins, filaggrin and involucrin. Propolis exhibited similar effects in AD‐like human skin, leading to the suppression of AD markers and the restoration of barrier proteins. In DNCB‐induced mice, oral administration of propolis attenuated AD symptoms, improved barrier function, and reduced scratching frequency and transepidermal water loss (TEWL). In addition, propolis reversed the mRNA levels of AD‐related markers in mouse dorsal skin. These effects were attributed to caffeic acid phenethyl ester (CAPE), the active compound identified by comparing major components of propolis. Mechanistic studies revealed that CAPE as well as propolis could directly and selectively target MKK4. Collectively, these findings demonstrate that propolis may be used as a functional food agent for the treatment of AD. [ABSTRACT FROM AUTHOR]

Calix[4]arenes 1 and 2 bearing two diametrical triazolyl anthracenes on the lower rim have been synthesized as a dual optical sensor and a fluorogenic cation sensor, respectively. UV/vis spectroscopy and fluorescence spectroscopy analyses revealed that receptors 1 and 2 are able to recognize divalent cations such as Ca2+, Zn2+, Ba2+, Hg2+, and Pb2+ with a significantly higher preference for Hg2+, giving rise to different color and fluorescence changes. It was also confirmed by 1H NMR spectroscopy and fluorescence spectroscopy analyses carried out in acetonitrile that receptor 1 binds the cations via different binding modes resulting in distinct colorimetric and fluorometric responses. [ABSTRACT FROM AUTHOR]

Tripyrromethane‐based tripodal compounds 1–3 were synthesized as anion receptors. It was revealed by 1H NMR spectroscopic analyses carried out in CDCl3 that tripyrromethane 1 with an ester group was capable of recognizing F−, Cl−, Br−, and H2PO4− with relatively high selectivity for F−. By contrast, receptor 2 having an additional hydrogen bond donor of an amide group binds F− and H2PO4− with much improved affinity relative to receptor 1. On the other hand, receptor 3 bearing formyl groups on its two pyrrole subunits showed markedly enhanced selectivity for F− presumably due to the increased acidity of the pyrrolic NHs and the resulting strengthened intermolecular hydrogen bonds. In addition, tripodal receptors 1–3 were found to bind H2PO4−, a tetrahedral oxyanion, more efficiently than 2‐dimensional macrocyclic calix[4]pyrrole 4. [ABSTRACT FROM AUTHOR]

Abstract Naphthalimide-decorated fluorinated acetamides 1 and 2 were developed as solvent-sensitive dual emissive fluorescence probes. Particularly, 1 exhibited dual emission with a large Stokes shift for water, DMF, and DMSO solvents over other various organic solvents. The dual emission might be due to the increase of intramolecular charge transfer (ICT) of the naphthalimide moiety through the association of the difluorinated acetamide group with the solvent molecules. The 1 can give rise to a ratiometric change in the dual emission and a visual fluorescent color change depending on the water contents in organic solvents, including ethanol, methanol, acetonitrile and DMF solvents. Moreover, the 1 -impregnated paper strips showed a rapid and easy-to-visualize fluorescent color change enabling water detection in organic solvents. These simple-to-use paper strips were also found to be reusable over 20 times. Graphical abstract Image 1 Highlights • Naphthalimide-decorated fluorinated acetamide probes 1 and 2 were synthesized. • Probe 1 could exhibit a dual fluorescence emission toward water, DMSO, and DMF. • Probe 1 could detect water in organic solvents, e.g., EtOH, MeOH, ACN, DMF, etc. • Probe 1 gave an easy-to-visualize fluorescent color change to water in organic solvents. • The 1 -impregnated paper strips can show a rapid and reversible fluorescence change. [ABSTRACT FROM AUTHOR]

Review: 30 refs. [ABSTRACT FROM AUTHOR]

Two new hybrid calixarene-calixpyrrole systems (III) and (V) are prepared according to the scheme. [ABSTRACT FROM AUTHOR]

As the market for electric vehicles and portable electronic devices continues to grow rapidly, sodium-ion batteries (SIBs) have emerged as energy storage systems to replace lithium-ion batteries (LIBs). However, sodium-ion is heavier and larger than lithium-ion, resulting in volume expansion and slower ion transfer. It is necessary to find suitable anode materials with high capacity and stability. In addition, wearable electronics are starting to be commercialized, requiring a binder-free electrode used in flexible batteries. In this work, we synthesized nano flake-like VSe2 using organic precursor and combined it with MWCNT as carbonaceous material. VSe2@MWCNT was mixed homogenously using sonication and fabricated film electrodes without a binder and substrate via vacuum filter. The hybrid electrode exhibited high-rate capability and stable cycling performance with a discharge capacity of 469.1 mAhg−1 after 200 cycles. Furthermore, VSe2@MWCNT exhibited coulombic efficiency of ~99.7%, indicating good cycle stability. Additionally, VSe2@MWCNT showed a predominant 85.5% of capacitive contribution at a scan rate of 1 mVs−1 in sodiation/desodiation process. These results showed that VSe2@MWCNT is a suitable anode material for flexible SIBs. [ABSTRACT FROM AUTHOR]

A naphthalene imide (1) and a naphthalene (2) bearing two pyrrole units have been synthesized, respectively, as anion receptors. It was revealed by 1H NMR spectral studies carried out in CD3CN that receptors 1 and 2 bind various anions via hydrogen bonds using both C-H and N-H donors. Compared with receptor 2, receptor 1 shows higher affinity for the test anions because of the enhanced acidity of its pyrrole NH and naphthalene CH hydrogens by the electron-withdrawing imide substituent. Molecular mechanics computations demonstrate that the receptors contact the halide anions via only one of the two respective available N-H and C-H donors whereas they use all four donors for binding of the oxyanions such as dihydrogen phosphate and hydrogen pyrophosphate. Receptor 1, a push-pull conjugated system, displays a strong fluorescence centered at 625 nm, while receptor 2 exhibits an emission with a maximum peak at 408 nm. In contrast, upon exposure of receptors 1 and 2 to the anions in question, their fluorescence was noticeably quenched particularly with relatively basic anions including F−, H2PO4−, HP2O73−, and HCO3−. [ABSTRACT FROM AUTHOR]

• Multi-modal mass transport is achieved in a pH-responsive block copolymer membrane. • Reversible oxidative wetting and dewetting are controlled by potential in hydrophobic membranes. • Potential-correlated electrochemiluminescence enables direct observation of wetting. Inspired by the hydrophobic gating for achieving fast and selective ion/molecular transport in cell membranes, wetting/dewetting transition in solid-state nanopores controlled by external stimuli such as voltage, pH, electrostatics, and light have attracted increasing attention. For an accurate and better understanding, a single nanopore or low-density array of nanopores was preferred to investigate the wetting and dewetting transitions owing to their well-defined chemical functions and physical structures. However, high-density nanochannel membranes capable of processing high-throughput and multi-modal mass transport are more beneficial with the aim of practical use. In this regard, pH- and potential-responsive nanochannel membranes consisting of a polystyrene- b -poly(4-vinylpyridine) (PS- b -P4VP) block copolymer (BCP) are prepared to demonstrate a multi-modal transport system with high-throughput capability. At pH < p K a (P4VP) (p K a ∼ 4.8), the cylindrical P4VP nanodomains are hydrophilic and positively charged, acting as an anion-exchange membrane. In contrast, at pH > p K a (P4VP), the P4VP domains switch to be charge-neutral and hydrophobic, naturally blocking the mass transport through the nanochannels. Applying a sufficiently positive potential to a BCP membrane-coated electrode may induce oxidative wetting in the hydrophobic nanochannels to facilitate mass transport across the membrane with no charge-selectivity. Releasing the bias makes the hydrophobic nanochannel membranes retrieve the original dewetted state, blocking the transport again. In addition, direct observation of the wetting-dewetting transition dynamics in the hydrophobic nanochannels is investigated by monitoring potential-correlated electrochemiluminescence (ECL) signals arising from Ru(bpy) 3 2+ and co-reactant tripropylamine (TPA) under potential modulations. ECL signals tend to decrease with increasing membrane thickness ranging from 0 nm to 820 nm because it requires higher potentials to induce wetting in the nanochannels due to elongated hydrophobic nanochannels. The multi-modal transport system developed in the present work will be useful for applications such as water treatment, biosensors, and smart valve systems like controlled drug release/delivery. [ABSTRACT FROM AUTHOR]

The iodination of pyrimidines is usually carried out by using toxic reagents under acidic conditions, such as with sulfuric acid and nitric acid. To avoid toxic reagents, we developed a simple and eco-friendly approach for the iodination of pyrimidine derivatives under solvent-free conditions using solid iodine and AgNO3 as an electrophilic iodinating reagent. The advantages of this method are the relatively short reaction time (20–30 min), simple set-up procedure, high yields (70–98%), and environmentally friendly reaction conditions. Our novel approach for the iodination of pyrimidines, as well as a variety of their derivatives, will contribute to the development of nucleobase-related drug candidates. [ABSTRACT FROM AUTHOR]

Fluorogenic benzothiazole-based receptor has been easily immobilised onto filter paper and silica nanoparticle by sol-gel reaction. The sensing ability of the benzothiazole-immobilised thin layer filter paper chromatography (TLC-1) was evaluated on the basis of fluorescent changes caused by metal ions that were dropped onto the TLC plate. TheTLC-1exhibited a high affinity and selectivity for Hg2+over other competing metal ions. Therefore, theTLC-1holds promise as a portable sensor for the detection of Hg2+in aqueous solution. Furthermore, the adsorption capacity of a column packed withSiO2-1was evaluated by the application of metal ions under various experimental conditions, such as pH, flow rate and concentration. TheSiO2-1column removed 98% of Hg2+from drinking water containing 10 ppb of Hg2+. The adsorption capacity of theSiO2-1column was not strongly affected by pH and flow rates. [ABSTRACT FROM AUTHOR]

Tripodal ion pair receptors 1 and 2 consisting of tris(pyridine‐2‐ylmethyl)amine as a cation binding site linked with nitrophenyl urea or amidonitroindole groups as anion binding motifs have been synthesized. 1H NMR spectroscopic analyses carried out in 10 % DMSO in acetonitrile revealed that both ion pair receptors 1 and 2 are able to bind the LiCl ion pair with high selectivity over NaCl, KCl, RbCl, and CsCl. 1H NMR spectroscopic analyses in combination with molecular mechanics calculations proved that the lithium cation is bound to the tris(pyridin‐2‐ylmethyl)amine subunit while the chloride anion interacts with the NHs of urea or amido indole groups via hydrogen bonds. The addition of fluoride to the lithium cation complexes of receptors 1 and 2 leads to the release of the lithium cation from the receptors whereas chloride and bromide are co‐bound with lithium forming LiCl and LiBr ion pair complexes, respectively. The affinity of receptor 1 for the lithium cation was found to be improved by 5.0‐fold when the counter anion of Cl− is co‐bound within the receptor. [ABSTRACT FROM AUTHOR]

Abstract: A new calix[4]arene-based fluorescence chemosensor displaying a strong excimer emission was prepared. When a Pb2+ ion is bound to the two amide oxygen atoms linked to the fluorophores, the ligand exhibits a marked quenched excimer emission due to its geometrical change during the complexation. By the addition of Ca2+ ion into the 1·Pb2+, the excimer emission band was revived, by which an interesting on/off switch process is proposed. [Copyright &y& Elsevier]

Abstract: Electrochemical adsorptive cathodic stripping voltammetry determination of Ge(IV) using the catechol complex on a mercury-coated (MC) electrode was prepared using a glassy carbon electrode (GCE), the peak potential of which was −0.5V vs. Ag/AgCl on MCGCE. The various parameters of the catechol concentration, its pH, and others were optimized. The linear working ranges were obtained in the concentration of 2–700μgL−1 Ge(IV). The relative standard deviation at the Ge(IV) concentration of 50μgL−1 was 1.37% (n =15) using the optimum condition, and the detection limit was found to be 0.6μgL−1 (8.26×10−9 M) (S/N=3), with an adsorption time of 180s. The Ge(IV) response was highly linear. This developed method was applied to Ge(IV) to determine the presence of rice grains. [Copyright &y& Elsevier]

As a novel sensing system, N-(1-pyrenylmethyl) amide-appended calix[4]crown-5 () and crown-6 () have been newly synthesized. Judging from the fluorescence changes upon the addition of cations, having crown-6 ring showed the Pb2+ ion selectivity over other cations tested regarding fluorescence quenching. Upon the Pb2+ ion coordination to two amide oxygen atoms with aid of crown ring, a reverse-photo-induced electron transfer (PET) occurs in such a way that electrons transfer from the pyrene groups to the electron deficient amide oxygen atoms to give a quenched fluorescence. By the addition of either HClO4 or triethylamine in the solution of , the fluorescence intensity decreased because of the reverse-PET from pyrene groups to protonated amide oxygen atoms and because of normal PET from the nitrogen anion formed by triethylamine to pyrene groups, respectively. For , NOR logic gate in which the strong fluorescence signal appears at 395 nm (output: 1) is operated only when neither of triethylamine nor Pb(ClO4)2 (inputs A and B) is added (A=B: 0). XNOR gate is also operated only when both of two inputs are added (triethylamine and HClO4, A=B: 1) or when neither of two inputs is added (A=B: 0). Then, for , new INHIBIT gate system was also designed using such combinational inputs as HClO4, Pb(ClO4)2 and triethylamine. [Copyright &y& Elsevier]

A calix[4]pyrrole (1) strapped with a naphthobipyrrole was prepared and its ability to bind the bicarbonate anion (HCO3−) was investigated via 1H NMR and UV/Vis spectroscopic analyses. The resulting spectral data revealed that receptor 1 was capable of recognizing HCO3− with high affinity in solutions as well as in the solid state. In CD2Cl2, it was inferred from 1H NMR spectroscopic titration experiment that HCO3− interacts with receptor 1 via two different modes with the first involving HCO3− being hydrogen bonded to all six NH protons of the receptor. This interaction is followed by a deprotonation process of the bipyrrole NHs upon the subsequent addition of HCO3− while the anion remains hydrogen‐bonded to the calix[4]pyrrole NHs. In the presence of methanol, the bound bicarbonate anion was converted into an unstable monomethyl carbonate anion (CH3OCO2−) that was then stabilized by forming a complex with receptor 1. [ABSTRACT FROM AUTHOR]

We used 2,6–diaminoanthraquinone (1), which is a famous dye derivative, and hexamethylene diisocyanate (2) for the urea formation. In general, the urea moieties between amine and cyanate are formed without a catalyst. In recent research, however, there have been several reports on urea reactions using a catalyst. In this paper, we studied the effect on gel formation of using dibutyltin dilaurate (DBTDL) as a catalyst. We observed the NMR measurement to determine the gelation time with and without the catalyst. In the presence of the catalyst, the reaction time was faster, as the gel formation shortened two fold. New NH groups of urea moieties generated by the reaction of amine groups of 1 with diisocyanate groups of 2 were also confirmed via 1H NMR observation, which indicate that urea moieties acted as a driving force of their self-assembly. Interestingly, the integral ratio of the new NH peak generated during the reaction in the presence of the catalyst was about seven times larger than that without the catalyst, indicating that the former urea reaction was larger. The anthraquinone-urea gels formed in the presence of catalyst showed fibrous structures with 2-µm lengths. However, the anthraquinone-urea gel formed in the absence of the catalyst showed honeycomb structures. The effect of the catalyst on the mechanical properties of the anthraquinone-urea gel was investigated by rheological measurement. In this case, the anthraquinone-urea gel showed values of viscosity and elasticity that were approximately 100 times larger in the presence of the catalyst. Furthermore, we suggest the anthraquinone-urea gel acted as a sensor for detecting fluoride ions by using the spectroscopic properties. [ABSTRACT FROM AUTHOR]

Summary: Background: Tegoprazan is a novel potassium‐competitive acid blocker for the treatment of acid‐related disorders. Aims: To assess whether tegoprazan is non‐inferior to lansoprazole in terms of efficacy and safety in patients with gastric ulcers. Methods: In this phase 3, double‐blind, active control, multicentre study, 306 gastric ulcer patients were randomised to one of three treatment groups: tegoprazan 50 mg, tegoprazan 100 mg and lansoprazole 30 mg once daily for 4 or 8 weeks. The primary endpoint was the cumulative proportion of patients with healed ulcers confirmed by endoscopy up to 8 weeks from treatment initiation. Symptoms and safety were assessed. Results: In the full analysis set, the cumulative healing rates at week 8 were 94.8% (91/96) for the tegoprazan 50 mg, 95.0% (94/99) for the tegoprazan 100 mg and 95.7% (89/93) for the lansoprazole 30 mg groups. At week 4, the respective healing rates were 90.6% (87/96), 91.9% (91/99), and 89.2% (83/93). In per protocol analysis, 4‐week healing rates were 95.4% (84/88), 94.6% (88/93) and 92.9% (79/85) for tegoprazan 50 mg, tegoprazan 100 mg and lansoprazole 30 mg, respectively. Both doses of tegoprazan were non‐inferior to lansoprazole in ulcer healing at 4 and 8 weeks. The incidence of drug‐related treatment‐emergent adverse events did not differ among groups. The increase in serum gastrin concentration was not higher in tegoprazan‐treated patients than in lansoprazole‐treated patients. Conclusions: Tegoprazan 50 or 100 mg were not inferior to lansoprazole 30 mg once daily in the treatment of gastric ulcers. [ABSTRACT FROM AUTHOR]

Supramolecular chemistry is a central topic in modern chemistry. It touches on many traditional disciplines, such as organic chemistry, inorganic chemistry, physical chemistry, materials chemistry, environmental chemistry, and biological chemistry. Supramolecular hosts, inter alia macrocyclic hosts, play critical roles in supramolecular chemistry. Calix[4]pyrroles, non-aromatic tetrapyrrolic macrocycles defined by sp3 hybridized meso bridges, have proved to be versatile receptors for neutral species, anions, and cations, as well as ion pairs. Compared to the parent system, octamethylcalix[4]pyrrole and its derivatives bearing simple appended functionalities, strapped calix[4]pyrroles typically display enhanced binding affinities and selectivities. In this review, we summarize advances in the design and synthesis of strapped calix[4]pyrroles, as well as their broad utility in molecular recognition, supramolecular extraction, separation technology, ion transport, and as agents capable of inhibiting cancer cell proliferation. Future challenges within this sub-field are also discussed. [ABSTRACT FROM AUTHOR]

A small molecular cage (4) with high affinity and complete selectivity for fluoride to the limit of detection over other competing small anions was synthesized. Cage 4 was also found to retain the encapsulated fluoride anion within its cavity even after one or two pyrrolic NH protons were subject to deprotonation. [ABSTRACT FROM AUTHOR]

The binding properties of the pyrrole-strapped calix[4]pyrrole 2 for cesium halide ion pairs were studied via 1H NMR spectroscopic and single crystal X-ray diffraction analyses. Receptor 2 was found to bind CsF, CsCl, and CsBr in the solid state and in chloroform/methanol (4/1, v/v) solution with relatively high affinity as compared with the parent calix[4]pyrrole 1. It was also revealed by solid-liquid extraction experiments that receptor 2 was capable of solubilizing CsF in CDCl3, a medium in which this salt is otherwise insoluble. Single crystal X-ray diffraction analyses and 1H NMR spectroscopic data recorded in 20% CD3OD in CDCl3 provide support for the suggestion that the strap pyrrolic NH proton of 2, as well as those of the calix[4]pyrrole framework, contribute to anion recognition, thus increasing affinity for cesium halide salts relative to the parent system 1. [ABSTRACT FROM AUTHOR]

[Display omitted] • Combining LC-MS/MS and CODA/COCONUT predicted propolis-associated immune diseases. • Propolis displayed therapeutic effects against atopic dermatitis. • CODA/COCONUT provided compound-associated genes based on constituents of propolis. • Propolis regulated the expression of target genes predicted by the network analysis. • Active compounds of propolis and their combinatorial effects was discovered. Discovering new bioactivities and identifying active compounds of food materials are major fields of study in food science. However, the process commonly requires extensive experiments and can be technically challenging. In the current study, we employed network biology and cheminformatic approaches to predict new target diseases, active components, and related molecular mechanisms of propolis. Applying UHPLC-MS/MS analysis results of propolis to Context-Oriented Directed Associations (CODA) and Combination-Oriented Natural Product Database with Unified Terminology (COCONUT) systems indicated atopic dermatitis as a novel target disease. Experimental validation using cell- and human tissue-based models confirmed the therapeutic potential of propolis against atopic dermatitis. Moreover, we were able to find the major contributing compounds as well as their combinatorial effects responsible for the bioactivity of propolis. The CODA/COCONUT system also provided compound-associated genes explaining the underlying molecular mechanism of propolis. These results highlight the potential use of big data-driven network biological approaches to aid in analyzing the impact of food constituents at a systematic level. [ABSTRACT FROM AUTHOR]

Hypothesis Semiconductor nanocrystals with response in the near-infrared region include lead chalcogenide quantum dots (QDs), and these materials show a strong quantum confinement effect due to their large Bohr radius compared with the group II–VI QDs. In the present study, a facile synthesis of lead selenide (PbSe) QDs using a pulsed laser irradiation in liquid (PLIL) is presented. Experiments PbSe QDs were produced using a pulsed Nd:YAG laser (532 nm, 10 Hz, 7 ns) irradiation of the Pb and Se mixed precursor solutions using the following three surfactants at various concentrations: cetyltrimethylammonium bromide (CTAB), sodium dodecyl sulfate (SDS), and polyvinylpyrrolidone (PVP). Findings Interestingly, it was observed that the synthesis and particle size of PbSe QDs obtained via the PLIL technique were strongly influenced by the type and concentration of the surfactants and by the varying wavelength and power of the laser. A secondary irradiation of the prepared sample in PVP solution resulted in the formation of rock salt crystalline PbSe QDs that were approximately 6.83 nm in size. [ABSTRACT FROM AUTHOR]

Abstract: LiCl is a classic “hard” ion salt that is present in lithium‐rich brines and a key component in end‐of‐life materials (that is, used lithium‐ion batteries). Its isolation and purification from like salts is a recognized challenge with potential strategic and economic implications. Herein, we describe two ditopic calix[4]pyrrole‐based ion‐pair receptors (2 and 3), that are capable of selectively capturing LiCl. Under solid–liquid extraction conditions, using 2 as the extractant, LiCl could be separated from a NaCl/KCl salt mixture containing as little as 1 % LiCl with circa 100 % selectivity, while receptor 3 achieved similar separations when the LiCl level was as low as 200 ppm. Under liquid–liquid extraction conditions using nitrobenzene as the non‐aqueous phase, the extraction preference displayed by 2 is KCl>NaCl>LiCl. In contrast, 3 exhibits high selectivity towards LiCl over NaCl and KCl, with no appreciable extraction being observed for the latter two salts. [ABSTRACT FROM AUTHOR]

Abstract: LiCl is a classic “hard” ion salt that is present in lithium‐rich brines and a key component in end‐of‐life materials (that is, used lithium‐ion batteries). Its isolation and purification from like salts is a recognized challenge with potential strategic and economic implications. Herein, we describe two ditopic calix[4]pyrrole‐based ion‐pair receptors (2 and 3), that are capable of selectively capturing LiCl. Under solid–liquid extraction conditions, using 2 as the extractant, LiCl could be separated from a NaCl/KCl salt mixture containing as little as 1 % LiCl with circa 100 % selectivity, while receptor 3 achieved similar separations when the LiCl level was as low as 200 ppm. Under liquid–liquid extraction conditions using nitrobenzene as the non‐aqueous phase, the extraction preference displayed by 2 is KCl>NaCl>LiCl. In contrast, 3 exhibits high selectivity towards LiCl over NaCl and KCl, with no appreciable extraction being observed for the latter two salts. [ABSTRACT FROM AUTHOR]

Calix[4]arene-based cation receptor 1 has been synthesised by following a multi-step synthetic procedure. The fluorescence properties of 1 upon the addition of various metal ions were investigated by fluorescence spectroscopy. As a result, it was revealed that 1 displayed dramatic quenching effect upon the exposure to Cs+. In contrast, no significant quenching effects were observed upon the addition of other metal ions such as Li+, Na+, K+, Mg2+, Ca2+, Sr2+, Ag+, Zn2+and Ni2+. Compound 1 was also found by Job plot to form a 1:1 complex with Cs+. In addition, we also prepared 1-embedded electrospun nanofibrous film (NF-1) as an adsorbent for Cs+. NF-1 is proved to adsorb Cs+effectively from an aqueous solution, indicating that it would be usefully utilised as an adsorbent to remove Cs+. [ABSTRACT FROM PUBLISHER]

With growing demands for large-scale energy storage, metal sulfides have received great attention due to their high theoretical capacity as anode materials for sodium-ion batteries (SIBs). However, metal sulfides have a problem of poor stability. Thus, it is important to find suitable solutions. In this work, uniform ZnS nanospheres (ZnS NSs) are synthesized through a wet chemical method. And then, by compounding with reduced graphene oxide (rGO), ZnS NSs@rGO are synthesized in which ZnS NSs are evenly distributed on rGO. When we evaluate the cycle performance, ZnS NSs@rGO deliver a high discharge capacity of 634.6 mA h g−1 at a current density of 0.5 Ag−1 after 1000 cycles. Through charge/discharge processes of in-situ XRD analysis, we confirm the sodiation/desodiation mechanism of ZnS NSs@rGO. • ZnS nanospheres (ZnS NSs) were synthesized by a colloidal method and then composite with ZnS NSs and rGO (ZnS NSs@rGO). • Real-time monitoring of phase transition revealed the sodium-ion storage mechanism of ZnS. • An appropriate combination of ZnS NSs and rGO led to outstanding cycle performance and cycle stability (634.6 mA h g−1 at 0.5 Ag−1 after 1000 cycles). [ABSTRACT FROM AUTHOR]

[Display omitted] • Multi-layered SnO nanoparticles were synthesized in one step and their morphology are unique shown in the previous reports. • The Na+ storage mechanism of the SnO electrode was investigated by ex-situ X-ray diffraction (XRD). • Cyclic voltammogram from 0.5 to 10 mV/s was obtained to investigate the electrochemical reaction kinetics of SnO/rGO. • The SnO/rGO nanocomposite showed high discharge capacity and cycling stability (338.7 mAh/g at 500 mA/g after 500 cycles). Metal oxide-based anodes have gained attention with their high theoretical capacity for Sodium–Ion Batteries (SIBs). However, their practical application is restricted due to huge volume expansion and low electronic conductivity caused by continuous cycling. This paper uses tin oxide/reduced graphene oxide (SnO/rGO) composites to solve the problems of low discharge capacity and poor cycling stability. The SnO/rGO nanocomposite electrode exhibits improved specific capacity, superior stability, and excellent rate property (a discharge capacity of 391.9 mAh/g at 100 mA/g after 120 cycles with capacity retention of 96.2 % and 338.7 mAh/g at 500 mA/g after 500 cycles with capacity retention of 92.2 %). Also, ex-situ XRD measurements are conducted to analyze the Na+ storage process in SnO. This study aims to expand the prospects of SnO/rGO nanocomposite anode for application in SIBs. [ABSTRACT FROM AUTHOR]

A 3-dimensional networked molecular cage, NMC-1, has been synthesized. This macrocycle-based framework was prepared from a solvothermal reaction involving a flexible organic building block, calix[4]pyrrole dibenzoic acid (H2L), and Pr(NO3)3·6H2O. A unique feature of NMC-1 is that it retains free calix[4]pyrrole molecules in the framework pores. Treatment with a fluoride anion source serves to destroy the network and allows release of the organic guest. The net result is a ‘molecular ship’ in a ‘breakable bottle’. [ABSTRACT FROM AUTHOR]

A calix[4]pyrrolefused with 2,5-dihydrothiophene, possessing botha deep, π-electron-rich pocket upon anion binding and chelatingligands on the periphery, was developed. The receptor selectivelyforms an ion-pair complex with CsF through H-bonding and a cation−πinteraction. In the process, it adopt a conformationally fixed coneconformation. The receptor displays exceptionally high affinity towardthe Hg(II) ion and forms stable complexes while maintaining a rigid1,3-alternate conformation. This metal ion-induced conformationallocking is unprecedented in calix[4]pyrrole chemistry. [ABSTRACT FROM AUTHOR]

Background: Phospholipase C-γl (PLC-γl) is known to play a critical role in cell adhesion and migration and is highly expressed in metastatic tumors. In the current study, we found that cells transformed by PLC overexpression (PLC-γl cells) exhibited a marked decrease in expression of the Epo receptor (EpoR). Here, we assessed the role of EpoR-dependent signaling pathways in PLC-γl-dependent regulation of cell adhesion and migration. Methods: Expression and phosphorylation of EpoR and its functional role in PLC-γl cells were evaluated by immunoblot analysis or cell adhesion assay. The mechanism for PLC-γ1-induced EpoR downregulation was analyzed by blockage of proteosomal degradation with MG132. EpoR expression was also confirmed in colorectal cancer tissues in which PLC-γl was highly expressed. Results: EpoR was present on rat fibroblasts, where it functionally active and capable of increasing cell adhesion and migratory activity. However, PLC-γl cells significantly decreased the Epo-dependent effects via ubiquitination-proteosomal degradation of EpoR. A marked decrease of EpoR expression was confirmed in colorectal cancer tissues that showed high-level of PLC-γl expression. Conclusion: The Epo/EpoR complex plays a critical role in the adhesion and migration of rat fibroblasts, and its functional inactivation is associated with PLC-γl-dependent reduction of cell-matrix adhesion and this also affects cell migration. [ABSTRACT FROM AUTHOR]