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The aerobic electron transfer chain builds a proton gradient by proton coupled electron transfer reactions through a series of proteins. Complex I is the first enzyme in the sequence. Here transfer of two electrons from NADH to quinone yields four protons pumped from the membrane N- (negative, higher pH) side to the P- (positive, lower) side. Protons move through three linear antiporter paths, with a few amino acids and waters providing the route; and through the E-channel, a complex of competing paths, with clusters of interconnected protonatable residues. Proton loading sites (PLS) transiently bind protons as they are transported from N- to P-compartments. PLS can be individual residues or extended clusters of residues. The program MCCE uses Monte Carlos sampling to analyze the E-channel proton binding in equilibrium with individual Molecular Dynamics snapshots from trajectories of Thermus thermuphillus Complex I in the apo, quinone and quinol bound states. At pH 7, the five E-channel subunits (Nqo4, Nqo7, Nqo8, Nqo10, and Nqo11) take >25,000 protonation microstates, each with different residues protonated. The microstate explosion is tamed by analyzing interconnected clusters of residues along the proton transfer paths. A proton is bound and released from a cluster of five coupled residues on the protein N-side and to six coupled residues in the protein center. Loaded microstates bind protons to sites closer to the P-side in the forward pumping direction. MCCE microstate analysis identifies strongly coupled proton binding amongst individual residues in the two PLS clusters., Competing Interests: Declaration of competing interest Marilyn Gunner reports financial support was provided by National Science Foundation. Marilyn Gunner reports financial support was provided by DOE. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

The development of novel metal-organic frameworks (MOFs) as efficient photocatalysts for hydrogen peroxide production from water and oxygen is particularly interesting, yet remains a challenge. Herein, we have prepared four cyclic trinuclear units (CTUs) based MOFs, exhibiting good light absorption ability and suitable band gaps for photosynthesis of H 2 O 2 . However, Cu-CTU-based MOFs are not able to photocatalyzed the formation of H 2 O 2 , while the alteration of metal nodes from Cu-CTU to Ag-CTU dramatically enhances the photocatalytic performance for H 2 O 2 production and the production rates can reach as high as 17476 μmol g -1  h -1 with an apparent quantum yield of 4.72 %, at 420 nm, which is much higher than most reported MOFs. The photocatalytic mechanism is comprehensively studied by combining the isotope labeling experiments and DFT calculation. This study provides new insights into the preparation of MOF photocatalysts with high activity for H 2 O 2 production through molecular engineering., (© 2024 Wiley-VCH GmbH.)

The development of metal complexes for photosynthesis of hydrogen peroxide (H 2 O 2 ) from pure water and oxygen using solar energy, especially in the absence of any additives ( e.g. , acid, co-catalysts, and sacrificial agents), is a worthwhile pursuit, yet still remains highly challenging. More importantly, the O 2 evolution from the water oxidation reaction has been impeded by the classic bottleneck, the photon-flux-density problem of sunlight that could be attributed to rarefied solar radiation for a long time. Herein, we reported synthesis of boron dipyrromethene (BODIPY)-based cyclic trinuclear silver complexes (Ag-CTC), and they exhibited strong visible-light absorption ability, a suitable energy bandgap, excellent photochemical properties and efficient charge separation ability. The integration of BODIPY motifs as oxygen reduction reaction sites and silver ions as water oxidation reaction sites allows Ag-CTC to photosynthesize H 2 O 2 either from pure water or from sea water in the absence of any additives with a high H 2 O 2 production rate of 183.7 and 192.3 μM h -1 , which is higher than that of other reported metal-based photocatalysts. The photocatalytic mechanism was systematically and ambiguously investigated by various experimental analyses and density functional theory (DFT) calculations. Our work represents an important breakthrough in developing a new Ag photocatalyst for the transformation of O 2 into H 2 O 2 and H 2 O into H 2 O 2 ., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)

Metal-organic frameworks (MOFs) that exhibit dynamic phase-transition behavior under external stimuli could have great potential in adsorptive separations. Here we report on a zinc-based microporous MOF (JNU-80) and its reversible transformation between two crystalline phases: large pore (JNU-80-LP) and narrow pore (JNU-80-NP). Specifically, JNU-80-LP can undergo a dehydration-induced cluster consolidation under heat treatment, resulting in JNU-80-NP with a reduced channel that allows exclusion of di-branched hexane isomers while high adsorption of linear and mono-branched hexane isomers. We further demonstrate the fabrication of MOF-polymer composite (JNU-80-NP-block) and its application in the purification of di-branched isomers from liquid-phase hexane mixtures (98 % di-branched) at room temperature, affording the di-branched hexane isomers with 99.5 % purity and close to 90 % recovery rate over ten cycles. This work illustrates an interesting dehydration-induced cluster consolidation in MOF structure and the ensuing channel shrinkage for sieving di-branched hexane isomers, which may have important implications for the development of MOFs with dynamic behavior and their potential applications in non-thermal driven separation technologies., (© 2024 Wiley-VCH GmbH.)

The properties of two-dimensional covalent organic frameworks (2D COFs), including porosity, catalytic activity as well as electronic and optical properties, are greatly affected by their interlayer stacking structures. However, the precise control of their interlayer stacking mode, especially in a reversible fashion, is a long-standing and challenging pursuit. Herein, we prepare three 2D copper-organic frameworks, namely JNM-n (n = 7, 8, and 9). Interestingly, the reversible interlayer sliding between eclipsed AA stacking (i.e., JNM-7-AA and JNM-8-AA) and staggered ABC stacking (i.e., JNM-7-ABC and JNM-8-ABC) can be achieved through environmental stimulation, which endows reversible encapsulation and release of lipase. Importantly, JNM-7-AA and JNM-8-AA exhibit a broader light absorption range, higher charge-separation efficiency, and higher photocatalytic activity for sensitizing O 2 to 1 O 2 and O 2 •- than their ABC stacking isostructures. Consequently, JNM-8-AA deliver significantly enhanced photocatalytic activities for oxidative cross-coupling reactions compared to JNM-8-ABC and other reported homogeneous and heterogeneous catalysts., (© 2024. The Author(s).)

In plants and algae, the primary antenna protein bound to photosystem II is light-harvesting complex II (LHCII), a pigment-protein complex that binds eight chlorophyll (Chl) a molecules and six Chl b molecules. Chl a and Chl b differ only in that Chl a has a methyl group (-CH 3 ) on one of its pyrrole rings, while Chl b has a formyl group (-CHO) at that position. This blue-shifts the Chl b absorbance relative to Chl a . It is not known how the protein selectively binds the right Chl type at each site. Knowing the selection criteria would allow the design of light-harvesting complexes that bind different Chl types, modifying an organism to utilize the light of different wavelengths. The difference in the binding affinity of Chl a and Chl b in pea and spinach LHCII was calculated using multiconformation continuum electrostatics and free energy perturbation. Both methods have identified some Chl sites where the bound Chl type ( a or b ) has a significantly higher affinity, especially when the protein provides a hydrogen bond for the Chl b formyl group. However, the Chl a sites often have little calculated preference for one Chl type, so they are predicted to bind a mixture of Chl a and b . The electron density of the spinach LHCII was reanalyzed, which, however, confirmed that there is negligible Chl b in the Chl a -binding sites. It is suggested that the protein chooses the correct Chl type during folding, segregating the preferred Chl to the correct binding site.

As a rich green energy source, natural gas is widely used in many fields such as the chemical industry, automobile energy, and daily life. However, it is very challenging to separate and recover C 2 H 6 and C 3 H 8 from natural gas. Metal-organic frameworks (MOFs) as an emerging type of multi-pore porous materials show huge potential in gas adsorption separation. Herein, we report pillar-layered MOFs, Ni (BDC)(DABCO) 0.5 (DMOF-X), modified by halogen atoms (F, Cl, Br), and investigate their CH 4 /C 2 H 6 /C 3 H 8 separation performance. The experimental results show that DMOF-Cl exhibited a extremely high adsorption capacity for C 3 H 8 and C 2 H 6 . Under the conditions of 298 K and 100 kPa, the adsorption capacities for C 3 H 8 and C 2 H 6 on DMOF-Cl are as high as 6.23 and 4.94 mmol g -1 , which are superior to the values for most of the porous materials that have been reported. In addition, DMOF-Cl also shows high C 3 H 8 /CH 4 (5: 85, V/V) and C 2 H 6 /CH 4 (10: 85, V/V) separation selectivities, with values of 130.9 and 12.5, respectively. Finally, DMOF-Cl also demonstrated great potential as an adsorbent for separating C 3 H 8 /C 2 H 6 /CH 4 .

Construction of gold-based metal-organic frameworks (Au-MOFs) would bring the merits of gold chemistry into MOFs. However, it still remains challenging because gold cations are easily reduced to metallic gold under solvothermal conditions. Herein, we present the first example of Au-MOFs prepared from the networking of cyclic trinuclear gold(I) complexes by formal transimination reaction in a rapid (<15 min) and scalable (up to 1 g) fashion under ambient condition. The Au-MOFs feature uniform porosity, high crystallinity, and superior chemical stability toward base (i.e., 20 M NaOH). With open Au(I) sites in the skeleton, the Au-MOFs as heterogeneous catalysts delivered good performance and substrate tolerance for the carboxylation reactions of alkynes with CO 2 . This work demonstrates a facile approach to reticularly synthesize Au-MOFs by combining the coordination and dynamic covalent chemistry.

Purpose: Urothelial carcinoma (UC) is a common disease in developed counties. This study aimed to identify autocrine roles and signaling pathways of gremlin 1, DAN family BMP antagonist (GREM1), which inhibits tumor growth and epithelial-mesenchymal transition (EMT) in UC., Methods: Systematic in vitro and in vivo studies using genetic engineering, different urinary bladder urothelial carcinoma (UBUC)-derived cell lines, and mouse models were performed, respectively. Further, primary upper tract urothelial carcinoma (UTUC) and UBUC specimens were evaluated by immunohistochemistry., Results: GREM1 protein levels conferred better disease-specific and metastasis-free survival rates and played an independent prognostic factor in UTUC and UBUC. Hypermethylation is the primary cause of low GREM1 levels. In different UBUC-derived cell lines, the autocrine/secreted and glycosylated GREM1 interacted with transforming growth factor beta 1 (TGFB1) and inhibited TGFβ/BMP/SMAD signaling and myosin light chain 9 (MYL9) transactivation, subsequently cell proliferation and epithelial-mesenchymal transition (EMT). Secreted and glycosylated GREM1 also suppressed tumor growth, metastasis, and MYL9 levels in the mouse model. Instead, cytosolic GREM1 promoted cell proliferation and EMT by activating the tumor necrosis factor (TNF)/AKT/nuclear factor kappa B (NFκB) axis., Conclusions: Clinical associations, animal models, and in vitro indications provided solid evidence to show that the epithelial autocrine GREM1 is a novel tumor suppressor in UCs. The glycosylated-GREM1 hampered cell proliferation, migration, invasion, and in vitro angiogenesis through interaction with TGFB1 to inactivate TGFβ/BMP/SMAD-mediated EMT in an autocrine manner., (© 2023. Springer Nature Switzerland AG.)

Abstract: Cycling is a growing sport worldwide since the COVID-19 pandemic. With the growing availability and interest in long distance events, professional and amateur cyclists are pushing themselves further and harder than ever before. Training and nutrition should be understood by the sports medicine professional in order to guide counseling toward proper fueling to avoid health consequences. This article reviews macronutrients and micronutrients, periodized training and nutrition, and the relevance of the ketogenic diet for endurance cyclists riding greater than 90 min., (Copyright © 2023 by the American College of Sports Medicine.)

Protons participate in many reactions. In proteins, protons need paths to move in and out of buried active sites. The vectorial movement of protons coupled to electron transfer reactions establishes the transmembrane electrochemical gradient used for many reactions, including ATP synthesis. Protons move through hydrogen bonded chains of waters and hydroxy side chains via the Grotthuss mechanism and by proton binding and release from acidic and basic residues. MCCE analysis shows that proteins exist in a large number of protonation states. Knowledge of the equilibrium ensemble can provide a rational basis for setting protonation states in simulations that fix them, such as molecular dynamics (MD). The proton path into the Q B site in the bacterial reaction centers (RCs) of Rb. sphaeroides is analyzed by MD to provide an example of the benefits of using protonation states found by the MCCE program. A tangled web of side chains and waters link the cytoplasm to Q B . MCCE analysis of snapshots from multiple trajectories shows that changing the input protonation state of a residue in MD biases the trajectory shifting the proton affinity of that residue. However, the proton affinity of some residues is more sensitive to the input structure. The proton transfer networks derived from different trajectories are quite robust. There are some changes in connectivity that are largely restricted to the specific residues whose protonation state is changed. Trajectories with Q B •- [Wei et. al Photosynthesis Research volume 152, pages153-165 (2022)] showing only modest changes. While introducing new methods the study highlights the difficulty of establishing the connections between protein conformation.B [Wei et. al Photosynthesis Research volume 152, pages153-165 (2022)] showing only modest changes. While introducing new methods the study highlights the difficulty of establishing the connections between protein conformation., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)

Numerous Fe(II) spin-crossover (SCO) compounds have been developed in the past decades, while the reports on the SCO materials with halogen atoms acting as coordinating ligands remain rare. In this study, we synthesize three iron(II) halide complexes with a general formula of [Fe II (Py5Me 2 )X] + (Py5Me 2 = 2,6-bis[1,1-bis(2-pyridyl)ethyl]pyridine, X = Cl - or Br - ) that undergo complete SCO transitions at near room temperature. The SCO properties of these compounds are investigated in detail by magnetic measurements, variable-temperature single-crystal X-ray diffractions, and Mössbauer spectra analyses. Because of the good stability of the coordination structures and suitable ligand-field strength, these compounds show robust spin transitions in both solid state and solution.

Multifunctional materials with switchable magnetic and dielectric properties are crucial for the development of memory and sensor devices. Herein, we report a methoxy-bridged dinuclear iron-pyridyl complex [Fe 2 (4-picoline) 4 (NCS) 4 (μ-OCH 3 ) 2 ] ( 1 ), which shows simultaneous thermal-induced magnetic and dielectric switchings. Within the phase-transition temperature range, both magnetic switching and the dielectric anomaly were detected, in which the thermal hysteresis loops were 23 and 21 K, respectively. Detailed structural analyses revealed that these simultaneous switchings were rooted in the flexible rotatable ligands, which were actuated by readjusting the π-π intermolecular interactions between the pyridine ligands in the trans positions of the metal centers. These results were comprehensively investigated both experimentally and theoretically. This study presents a new guideline to control both the magnetic and dielectric properties of molecular complexes by external stimuli.

The design of adsorbents for rapid, selective extraction of ultra-trace amounts of gold from complex liquids is desirable from both an environmental and economical point of view. However, the development of such materials remains challenging. Herein, we report the fabrication of two vinylene-linked two-dimensional silver(I)-organic frameworks prepared via Knoevenagel condensation. This material enables selective sensing of gold with a low limit of detection of 60 ppb, as well as selective uptake of ultra-trace gold from complex aqueous mixtures including distilled water with 15 competing metal ions, leaching solution of electronic waste (e-waste), wastewater, and seawater. The present adsorbent delivers a gold adsorption capacity of 954 mg g -1 , excellent selectivity and reusability, and can rapidly and selectively extract ultra-trace gold from seawater down to ~20 ppb (94% removal in 10 minutes). In addition, the purity of recovered gold from e-waste reaches 23.8 Karat (99.17% pure)., (© 2022. The Author(s).)

The efficient separation of C 2 H 2 /CO 2 is challenging and energy intensive due to their similar molecular shapes and kinetic diameters. Here we report an ato-topology metal-organic framework (JNU-7a) with a specific surface area of 2046 cm 2 g -1 and open-metal-site density of 2.05 mmol cm -3 , resulting in a large C 2 H 2 adsorption capacity of (176 cm 3 g -1 ) and high C 2 H 2 /CO 2 adsorption selectivity (6.2).

The efficient separation of acetylene (C 2 H 2 ) from its mixture with carbon dioxide (CO 2 ) remains a challenging industrial process due to their close molecular sizes/shapes and similar physical properties. Herein, we report a microporous metal-organic framework (JNU-4) with square-planar mononuclear copper(ii) centers as nodes and tetrahedral organic linkers as spacers, allowing for two accessible binding sites per metal center for C 2 H 2 molecules. Consequently, JNU-4 exhibits excellent C 2 H 2 adsorption capacity, particularly at 298 K and 0.5 bar (200 cm 3 g -1 ). Detailed computational studies confirm that C 2 H 2 molecules are indeed predominantly located in close proximity to the square-planar copper centers on both sides. Breakthrough experiments demonstrate that JNU-4 is capable of efficiently separating C 2 H 2 from a 50 : 50 C 2 H 2 /CO 2 mixture over a broad range of flow rates, affording by far the largest C 2 H 2 capture capacity (160 cm 3 g -1 ) and fuel-grade C 2 H 2 production (105 cm 3 g -1 , ≥98% purity) upon desorption. Simply by maximizing accessible open metal sites on mononuclear metal centers, this work presents a promising strategy to improve the C 2 H 2 adsorption capacity and address the challenging C 2 H 2 /CO 2 separation., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Two-dimensional (2D) metal-organic framework nanosheets (MONs) or membranes are classes of periodic, crystalline polymeric materials that may show unprecedented physicochemical properties due to their modular structures, high surface areas, and high aspect ratios. Yet preparing 2D MONs from multiple components and two different types of polymerization reaction remains challenging and less explored. Here, we report the synthesis of MOF films via interfacial polymerization, which involves three active monomers for simultaneous polycondensation and polycoordination taking place in a confined interface. The well-defined lamellar structure of the MOF films allowed feasible and scalable exfoliation to produce free-standing 2D MONs with high aspect ratio up to 2000:1 and ultrathin thickness (∼1.7 nm). The pore structure was revealed by high-resolution TEM images with near-atomic precision. The imide-linkage of MONs provided superior thermal (up to 530 °C) and good chemical stability in the pH range from 3 to 12. More importantly, the MONs exhibited exceptional catalytic activity and superior reusability for the hydroboration reactions of alkynes, in which the turnover frequency (TOF) reached 41734 h -1 , which is 2-4 orders of magnitude greater than that reported for homogeneous and heterogeneous catalysts.

Although water-soluble graphene quantum dots (GQDs) have shown various promising bio-applications due to their intriguing optical and chemical properties, the large heterogeneity in compositions, sizes, and shapes of these GQDs hampers the better understanding of their structure-properties correlation and further uses in terms of large-scale manufacturing practices and safety concerns. It is shown here that a water-soluble atomically-precise GQD (WAGQD-C 96 ) is synthesized and exhibits a deep-red emission and excellent sonodynamic sensitization. By decorating sterically hindered water-soluble functional groups, WAGQD-C 96 can be monodispersed in water without further aggregation. The deep-red emission of WAGQD-C 96 facilitates the tracking of its bio-process, showing a good cell-uptake and long-time retention in tumor tissue. Compared to traditional molecular sonosensitizers, WAGQD-C 96 generates superior reactive oxygen species and demonstrates excellent tumor inhibition potency as an anti-cancer sonosensitizer in in vivo studies. A good biosafety of WAGQD-C 96 is validated in both in vitro and in vivo assays., (© 2022 The Authors. Advanced Science published by Wiley-VCH GmbH.)

The photosynthetic bacterial reaction centers from purple non-sulfur bacteria use light energy to drive the transfer of electrons from cytochrome c to ubiquinone. Ubiquinone bound in the Q A site cycles between quinone, Q A , and anionic semiquinone, Q A ·- , being reduced once and never binding protons. In the Q B site, ubiquinone is reduced twice by Q A ·- , binds two protons and is released into the membrane as the quinol, QH 2 . The network of hydrogen bonds formed in a molecular dynamics trajectory was drawn to investigate proton transfer pathways from the cytoplasm to each quinone binding site. Q A is isolated with no path for protons to enter from the surface. In contrast, there is a complex and tangled network requiring residues and waters that can bring protons to Q B . There are three entries from clusters of surface residues centered around HisH126, GluH224, and HisH68. The network is in good agreement with earlier studies, Mutation of key nodes in the network, such as SerL223, were previously shown to slow proton delivery. Mutational studies had also shown that double mutations of residues such as AspM17 and AspL210 along multiple paths in the network presented here slow the reaction, while single mutations do not. Likewise, mutation of both HisH126 and HisH128, which are at the entry to two paths reduce the rate of proton uptake., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)

Although heptagons are widely found in graphenic materials, the precise synthesis of nanocarbons containing heptagons remains a challenge, especially for the nanocarbons containing multiple-heptagons. Herein, we show that photo-induced radical cyclization (PIRC) can be used to synthesize multi-heptagon-embedded nanocarbons. Notably, a nanographene containing six heptagons (1) was obtained via a six-fold cascade PIRC reaction. The structure of 1 was clearly validated and showed a Monkey-saddle-shaped conformation. Experimental bond analysis and theoretical calculations indicated that the heptagons in 1 were non-aromatic, whereas the peripheral rings were highly aromatic. Compared to planar nanographene with the same number of π electrons, 1 had a similar optical gap due to a compromise between the decreased conjugation in the wrapped structure and enhanced electronic delocalization at the rim. Electrochemical studies showed that 1 had low-lying oxidation potentials, which was attributed to the nitrogen-doping., (© 2022 Wiley-VCH GmbH.)

Proteins are polyelectrolytes with acidic and basic amino acids Asp, Glu, Arg, Lys, and His, making up ≈25% of the residues. The protonation state of residues, cofactors, and ligands defines a "protonation microstate". In an ensemble of proteins some residues will be ionized and others neutral, leading to a mixture of protonation microstates rather than in a single one as is often assumed. The microstate distribution changes with pH. The protein environment also modifies residue proton affinity so microstate distributions change in different reaction intermediates or as ligands are bound. Particular protonation microstates may be required for function, while others exist simply because there are many states with similar energy. Here, the protonation microstates generated in Monte Carlo sampling in MCCE are characterized in HEW lysozyme as a function of pH and bacterial photosynthetic reaction centers (RCs) in different reaction intermediates. The lowest energy and highest probability microstates are compared. The Δ G , Δ H , and Δ S between the four protonation states of Glu35 and Asp52 in lysozyme are shown to be calculated with reasonable precision. At pH 7 the lysozyme charge ranges from 6 to 10, with 24 accepted protonation microstates, while RCs have ≈50,000. A weighted Pearson correlation analysis shows coupling between residue protonation states in RCs and how they change when the quinone in the Q B site is reduced. Protonation microstates can be used to define input MD parameters and provide insight into the motion of protons coupled to reactions.

Melodicochinines A - D (1-4), four new monoterpene indole alkaloids (MIAs), along with 21 known ones, were isolated from the stems and twigs of Melodinus cochinchinensis. Their structures were elucidated on the basis of extensive spectroscopic analysis. A ubiquitin-rhodamine 110 assay showed that 11-methyloxytabersonine had potential inhibitory effect against ubiquitin-specific protease 7 (USP7)., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Coordination complexes with aggregation-induced-emission (AIE) behavior has drawn much attention because of their promising applications. Conventionally, the AIE-active metal-organic complexes are prepared from an AIE-active organic ligand, and the construction of such coordination complexes from aggregation-caused-quenching (ACQ) ligands is still challenging. Herein, we have synthesized two new cyclic trinuclear complexes (CTCs), namely, 1 and 2 , from copper(I) and silver(I) and a ACQ ligand [4-(3,5-dimethyl-1 H -pyrazol-4-yl)benzaldehyde, HL ]. ( 1 ) exhibited AIE behavior, and the emission intensity is enhanced ∼20 times when it aggregates, which can be attributed to its tight packing and multiple intermolecular hydrogen bonds that restrained the intramolecular rotation, as confirmed by single-crystal X-ray diffraction analysis. On the other hand, ( 2 ) displayed ACQ effects, and the emission intensity is decreased ∼5 times when it aggregates. This ACQ behavior of 2 is related to its loose packing and free rotation of the ligand in crystals, resulting in nonradiative decay and fluorescence quenching. Interestingly, the CTCs 1 and 2 both exhibited a good affinity to gold(III) ions, allowing selective detection and sensing of gold ions. More importantly, the 2 shows a good limit of detection (3.28 μmol/L) and an ultrafast responsive time (∼2 s). Our studies pave a new route to designing novel AIE-active coordination complexes and further exploring the functionality of CTCs.

Well-studied cycloparaphenylenes (CPPs) correspond to the simplest segments of armchair CNTs, whereas the corresponding macrocyclic oligophenylene strip of zigzag CNTs is still missing. Herein, we present two series of conjugated macrocycles (CM2PP and CN2PP) containing two meta -phenylene or 2,7-naphthylene units facing each other in the strip. CM2PP and CN2PP can be regarded as the shortest cyclic primitive segments of zigzag CNTs. They were synthesized by gold-mediated dimerization and unambiguously characterized. They adopted the tubular structures and can further pack into one-dimensional supramolecular nanotubes. In particular, the supramolecular nanotube of CM2P4P mimics the CNT(9, 0) structure. Structural analysis and theoretical calculation accounted for the reduced ring strain in CM2PPs and CN2PPs. CM2PPs and CN2PPs exhibited a large optical extinction coefficient and high photoluminescence quantum yield. CN2P8P can accommodate fullerene C 60 , forming a Saturn-like C 60 @CN2P8P complex, a mimic structure of zigzag CNT peapods., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)

Blood flow inside the left ventricle (LV) is a concern for blood pump use and contributes to ventricle suction and thromboembolic events. However, few studies have examined blood flow inside the LV after a blood pump was implanted. In this study, in vitro experiments were conducted to emulate the intraventricular blood flow, such as blood flow velocity, the distribution of streamlines, vorticity and the standard deviation of velocity inside the LV during axial blood pump support. A silicone LV reconstructed from computerized tomography (CT) data of a heart failure patient was incorporated into a mock circulatory loop (MCL) to simulate human systemic circulation. Then, the blood flow inside the ventricle was examined by particle image velocimetry (PIV) equipment. The results showed that the operating conditions of the axial blood pump influenced flow patterns within the LV and areas of potential blood stasis, and the intraventricular swirling flow was altered with blood pump support. The presence of vorticity in the LV from the thoracic aorta to the heart apex can provide thorough washing of the LV cavity. The gradually extending stasis region in the central LV with increasing blood pump support is necessary to reduce the thrombosis potential in the LV.

Acmoxanthones A-E (1-5), five new lavandulylated xanthones, were isolated from the aerial parts of Hypericum acmosepalum, together with four known xanthones. Their structures with absolute configurations were elucidated on the basis of analysis of MS, NMR and chiroptical properties. A bioassay against high glucose-induced damage on human umbilical vein endothelial cells (HUVECs) showed ananixanthone (6) and osajaxanthone (7) had potential antioxidative damage activity with EC 50 values of 10.5 μg/mL and 7.6 μg/mL, respectively, while 3-hydroxy-2,4-dimethoxyxanthone (8) exhibited cytotoxic effect on the damaged cells with IC 50 values of 7.1 μg/mL., (Copyright © 2021. Published by Elsevier B.V.)

Rigid molecular sieving materials work well for small molecules with the complete exclusion of large ones 1-3 , and molecules with matching physiochemical properties may be separated using dynamic molecular sieving materials 4-6 . Metal-organic frameworks (MOFs) 7-9 are known for their precise control of structures and functions on a molecular level 10-15 . However, the rational design of local flexibility in the MOF framework for dynamic molecular sieving remains difficult and challenging. Here we report a MOF material (JNU-3a) featuring one-dimension channels with embedded molecular pockets opening to propylene (C 3 H 6 ) and propane (C 3 H 8 ) at substantially different pressures. The dynamic nature of the pockets is revealed by single-crystal-to-single-crystal transformation upon exposure of JNU-3a to an atmosphere of C 3 H 6 or C 3 H 8 . Breakthrough experiments demonstrate that JNU-3a can realize high-purity C 3 H 6 (≥99.5%) in a single adsorption-desorption cycle from an equimolar C 3 H 6 /C 3 H 8 mixture over a broad range of flow rates, with a maximum C 3 H 6 productivity of 53.5 litres per kilogram. The underlying separation mechanism-orthogonal-array dynamic molecular sieving-enables both large separation capacity and fast adsorption-desorption kinetics. This work presents a next-generation sieving material design that has potential for applications in adsorptive separation., (© 2021. The Author(s), under exclusive licence to Springer Nature Limited.)

Uralins A - D, four undescribed polycyclic polyprenylated acylphloroglucinols (PPAPs) featuring an unprecedented fused hexacyclic architecture, a unique monocyclic tetra-seco-tetranor-b-PPAP, an oxidative b-PPAP and a rare norspiroindane-type m-PPAP, respectively, were isolated from the aerial parts of Hypericum uralum, along with ten known PPAPs. Their structures and absolute configurations were elucidated by extensive spectroscopic techniques (MS, NMR, [α] D , CD), conceivable biogenetic pathways and time-dependent density functional theory-based electronic circular dichroism (TDDFT-ECD) calculations. Biological assays showed three b-PPAPs had moderate antioxidative damage activities, while spiroindanes exhibited moderate cytotoxic effects., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

We have experimentally shown by neutron diffraction significant shortening of both sp 3 - and sp 2 -hybridized C-H bonds to 1.092(2) and 1.081(1) Å in a hydrogen-bonded crystal of a difluorinated compound, 4-((2,2-difluoroethoxy)methyl)pyridinium saccharinate. Both MP2 and DFT calculations affirmed the C-H bond shrinkages. Sanderson's electronegativity equalization principle provides insight into the shortening of the C-H covalent bond lengths for both sp 3 - and sp 2 -hybridized carbon atoms. To the best of our knowledge, this neutron diffraction study has revealed the largest extents of sp 3 and sp 2 C-H bond shrinkages with a 3-sigma rule being satisfied.

Intraventricular blood stasis is a design consideration for continuous flow blood pumps and might contribute to adverse events such as thrombosis and ventricular suction. However, the blood flow inside left ventricles (LVs) supported by blood pumps is still unclear. In vitro experiments were conducted to imitate how the hydraulic performance of an axial blood pump affects the intraventricular blood flow of a severe heart failure patient, such as velocity distribution, vorticity, and standard deviation of velocity. In this study, a silicone model of the LV was constructed from the computed tomography data of one patient with heart failure and was 3D printed. Then, intraventricular flow was visualized by particle image velocimetry equipment within a mock circulation loop. The results showed that the axial blood pump suctions most of the blood in a severely failing LV, there was an altered flow status within the LV, and blood stasis appeared in the central region of the LV. Some blood may be suctioned from the aortic valve to the blood pump because the patient's native heart was severely failing. Blood stasis at the LV center may cause thrombosis in the LV. The vortex flow near the inner wall of the LV can thoroughly wash the left ventricular cavity., (© 2020 International Center for Artificial Organs and Transplantation and Wiley Periodicals LLC.)

Interest in piezochromic luminescence has increased in recent decades, even though it is mostly limited to pure organic compounds and fluorescence. In this work, a Cu 3 Pz 3 ( Cu3 , Pz: pyrazolate) cyclic trinuclear complex (CTC) with two different crystalline polymorphs, namely 1a and 1b , was synthesized. The CTC consists of two functional moieties: carbazole ( Cz ) chromophore and Cu3 units. In crystals of 1a , discrete Cz - Cu3 - Cu3 - Cz stacking was found, showing abnormal pressure-induced phosphorescence enhancement (PIPE), which was 12 times stronger at 2.23 GPa compared to under ambient conditions. This novel observation is ascribed to cooperation between heavy-atom effects ( i.e. , from Cu atoms) and metal-ligand charge-transfer promotion. The infinite π-π stacking of Cz motifs was observed in 1b and it exhibited good piezochromism as the pressure increased. This work demonstrates a new concept in the design of piezochromic materials to achieve PIPE via combining organic chromophores and metal-organic phosphorescence emitters., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

A unique metal-organic framework (MOF) with tetrazole-padded helical channels has been successfully synthesized in one pot from iron(II) trifluoromethanesulfonate, 4-formylimidazole, hydrazine, and sodium azide under solvothermal conditions and features a rare unh topology and porous structure for gas adsorption. Transformations of condensation, cycloaddition, and coordination occurred during the synthetic process, in which a 1,5-disubstituted tetrazole ligand was formed in situ.

The formation mechanism of ferrihydrite is the key to understand its treatment of pollutants in waste water and purification of surface water and groundwater. Although emerging evidence suggests that formation of the ferrihydrite occurs through the aggregation of prenucleation clusters, rather than classical atom-by-atom growth, its formation mechanism remains unclear. Herein, an iron-oxo anionic cluster of [Fe 22 (μ 4 -O) 8 (μ 3 -OH) 20 (μ 2 -OH) 18 (CH 3 COO) 16 (H 2 O) 2 ] 4- viewed as a dimer of bivacant β-Keggin-Fe 13 clusters was for the first time obtained by using lanthanide ions as stabilizers. Upon dissolution in a mixed solution of isopropanol and water, the lacunary β-Keggin-Fe 13 cluster can transform into an α-Keggin-Fe 13 cluster, distinctly demonstrating that the Keggin-Fe 13 cluster rotational isomerization can be realized through the vacant Keggin-Fe 13 cluster., (© 2020 Wiley-VCH GmbH.)

Since this article has been suspected of research misconduct and the corresponding authors did not respond to our request to prove originality of data and figures, "MiR-155 affects renal carcinoma cell proliferation, invasion and apoptosis through regulating GSK-3β/β-catenin signaling pathway, by R.-J. Wei, C.-H. Zhang, W.-Z. Yang, published in Eur Rev Med Pharmacol Sci 2017; 21(22): 5034-5041-DOI: 10.26355/eurrev&#95;201711&#95;13813-PMID: 29228417" has been withdrawn. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/13813.

The objective was to investigate the upstream mechanisms of apoptosis which were triggered by a novel antimicrotubule drug, ABT-751, in a tumor protein p53 ( TP53)-deficient hepatocellular carcinoma-derived Hep-3B cells. A series of in vitro assays indicated that ABT-751 caused the disruption of the mitotic spindle structure, collapse of mitochondrial membrane potential, generation of reactive oxygen species, DNA damage, G 2 /M cell cycle arrest, inhibition of anchorage-independent cell growth and apoptosis in Hep-3B cells accompanied by alteration of the expression levels of several DNA damage checkpoint proteins and cell cycle regulators. Subsequently, ABT-751 triggered apoptosis along with markedly upregulated several proapoptotic proteins involving in extrinsic, intrinsic, and caspase-mediated apoptotic pathways. A pan-caspase inhibitor suppressed ABT-751-induced apoptosis. ABT-751 also induced autophagy soon after the occurrence of apoptosis through the suppression of AKT serine/threonine kinase/mechanistic target of rapamycin signaling pathway. Exogenous expression of the TP53 gene significantly incurred both apoptosis and autophagy in Hep-3B cells. Pharmacological inhibition of autophagosome (early autophagy) but not autolysosome (late autophagy) enhanced ABT-751-induced apoptosis in TP53-deficient Hep-3B cells. Our study provided a new strategy to augment ABT-751-induced apoptosis in TP53-deficient cells., (© 2018 Wiley Periodicals, Inc.)

Basigin is a well-known extracellular stimulator of fibroblasts and may confer resistance to apoptosis of fibroblasts in vitro under some pathological status, but its exact function in fibroblasts and the underlying mechanism remain poorly understood. The systematic Basigin gene knockout leads to the perinatal lethality of mice, which limits the delineation of its function in vivo. In this study, we generated a fibroblast-specific Basigin knock-out mouse model and demonstrated the successful deletion of Basigin in fibroblasts. The fibroblast-specific deletion of Basigin did not influence the growth, fertility and the general condition of the mice. No obvious differences were found in the size, morphology, and histological structure of the major organs, including heart, liver, spleen, lung and kidney, between the knockout mice and the control mice. The deletion of Basigin in fibroblasts did not induce apoptosis in the tissues of the major organs. These results provide the first evidence that the fibroblast-specific Basigin knock-out mice could be a useful tool for exploring the function of Basigin in fibroblasts in vivo.

A new post-functionalization strategy for hybrid polyoxometalate (POM) clusters is presented, whereby the electronic properties and visible-light driven oxidative reactivity of the POM core can be altered by controlled addition of transition metal ions. The structure of three new metal-functionalised derivatives of a phosphonate hybrid-POM are discussed, alongside a comparison of their electrochemical, photo-chemical and photo-oxidative properties.

Objective: To explore the practicability and safety of the F4.8 visual miniature nephroscope in the diagnosis and treatment of hematospermia., Methods: This study included 12 cases of refractory hematospermia accompanied by perineal or lower abdominal pain and discomfort. All the patients failed to respond to two months of systemic anti-inflammatory medication and local physiotherapy. Seminal vesicle tumor and tuberculosis were excluded preoperatively by rectal seminal vesicle ultrasonography, MRI or CT. Under epidural anesthesia, microscopic examination was performed with the F4.8 miniature nephroscope through the urethra and ejaculatory duct orifice into the seminal vesicle cavity, the blood clots washed out with normal saline, the seminal vesicle stones extracted by holmium laser lithotripsy and with the reticular basket, the seminal vesicle polyps removed by holmium laser ablation and vaporization, and the seminal vesicle cavity rinsed with diluted iodophor after operation., Results: Of the 10 patients subjected to bilateral seminal vesiculoscopy, 3 with unilateral and 2 with bilateral seminal vesicle stones were treated by holmium laser lithotripsy, saline flushing and reticular-basket removal, 2 with seminal vesicle polyps by holmium laser ablation and vaporization, and the other 3 with blood clots in the seminal vesicle cavity by saline flushing for complete clearance. The 2 patients subjected to unilateral seminal vesiculoscopy both received flushing of the seminal vesicle cavity for clearance of the blood clots. The operations lasted 10－55 (25 ± 6) minutes. There were no such intra- or post-operative complications as rectal injury, peripheral organ injury, and external urethral sphincter injury. The urethral catheter was removed at 24 hours, anti-infection medication withdrawn at 72 hours, and regular sex achieved at 2 weeks postoperatively. The patients were followed up for 6－20 (7 ± 2.3) months, during which hematospermia and related symptoms disappeared in 10 cases at 3 months and recurrence was observed in the other 2 at 4 months after surgery but improved after antibiotic medication., Conclusions: The F4.8 visual miniature nephroscope can be applied to the examination of the seminal vesicle cavity and treatment of seminal vesicle stones and polyps, with the advantages of minimal invasiveness, safety and reliability.

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promising agent for anticancer therapy. The identification of small molecules that can establish the sensitivity of prostate cancer (PCa) cells to TRAIL-induced apoptosis is crucial for the targeted treatment of PCa. PC3, DU145, JAC-1, TsuPr1, and LNCaP cells were treated with Andrographolide (Andro) and TRAIL, and the apoptosis was measured using the Annexin V/PI double staining method. Real time-polymerase chain reaction (PCR) and Western blot analysis were performed to measure the expression levels of target molecules. RNA interference technique was used to down-regulate the expression of the target protein. We established a nude mouse xenograft model of PCa, which was used to measure the caspase-3 activity in the tumor cells using flow cytometry. In this research study, our results demonstrated that Andro preferentially increased the sensitivity of PCa cells to TRAIL-induced apoptosis at subtoxic concentrations, and the regulation mechanism was related to the up-regulation of DR4. In addition, it also increased the p53 expression and led to the generation of reactive oxygen species (ROS) in the cells. Further research revealed that the DR4 inhibition, p53 expression, and ROS generation can significantly reduce the apoptosis induced by the combination of TRAIL and Andro in PCa cells. In conclusion, Andro increases the sensitivity of PCa cells to TRAIL-induced apoptosis through the generation of ROS and up-regulation of p53 and then promotes PCa cell apoptosis associated with the activation of DR4.

Objective: Glycogen Synthase Kinase-3β (GSK-3β) negatively regulates Wnt/β-catenin signaling pathway through degrading β-catenin protein. It plays an inhibitory role in various tumors, while the influence in the pathogenesis of renal carcinoma has not been elucidated. MicroRNA-155 (MiR-155) was found to be upregulated in renal carcinoma tissue. Bioinformatics analysis revealed the complementary binding site between miR-155 and 3'-UTR of GSK-3β. This study investigated the influence of miR-155 in regulating GSK-3β expression, Wnt/β-catenin signaling pathway activity, and renal carcinoma cell proliferation, invasion, and apoptosis., Patients and Methods: The targeted regulatory relationship between miR-155 and GSK-3β were tested by dual luciferase assay. Renal carcinoma tissue and benign renal tissue were collected to detect miR-155 and GSK-3β expressions. MiR-155, GSK-3β, and β-catenin levels were compared between HK-2 and 786-O cells. Renal carcinoma 786-O cells were cultured in vitro and divided into four groups, including miR-NC, anti-miR-155, pIRES2-blank, and pIRES2-GSK-3β groups. Cell apoptosis was evaluated by flow cytometry. Cell invasion was determined by transwell assay. Cell proliferation was assessed by EdU staining., Results: MiR-155 targeted regulated GSK-3β expression. MiR-155 and β-catenin expressions were significantly increased, while GSK-3β level was significantly declined in renal carcinoma tissue compared with benign renal tissue. MiR-155 and β-catenin expressions were significantly elevated, whereas GSK-3β level was significantly downregulated in 786-O cells compared with HK-2 cells. Anti-miR-155 or pIRES2-GSK-3β transfection significantly up-regulated GSK-3β expression, attenuated β-catenin level, restrained cell proliferation and invasion, and enhanced cell apoptosis., Conclusions: MiR-155 promoted renal carcinoma pathogenesis. Inhibition of miR-155 increased GSK-3β expression, attenuated Wnt/β-catenin signaling pathway, weakened proliferation and invasion, and facilitated apoptosis in renal carcinoma cells.

This study explores a new method to maximize the visible-light-driven photocatalytic performance of organic-inorganic hybrid polyoxometalates (POMs). Experimental and theoretical investigations of a family of phosphonate-substituted POMs show that modification of grafted organic moieties can be used to tune the electronic structure and photoactivity of the metal oxide component. Unlike fully inorganic polyoxotungstates, these organic-inorganic hybrid species are responsive to visible light and function as photocatalysts (λ > 420 nm) in the decomposition of a model environmental pollutant. The degree of photoactivation is shown to be dependent on the nature of the inductive effect exerted by the covalently grafted substituent groups. This study emphasizes the untapped potential that lies in an orbital engineering approach to hybrid-POM design and helps to underpin the next generation of bespoke, robust, and cost-effective molecular metal oxide photoactive materials and catalysts.

The largest Ln-Fe metal cluster [Gd 12 Fe 14 (μ 3 -OH) 12 (μ 4 -OH) 6 (μ 4 -O) 12 (TEOA) 6 (CH 3 COO) 16 (H 2 O) 8 ]⋅(CH 3 COO) 2 (CH 3 CN) 2 ⋅(H 2 O) 20 (1) and the core-shell monodisperse metal cluster of 1 a@SiO 2 (1 a=[Gd 12 Fe 14 (μ 3 -OH) 12 (μ 4 -OH) 6 (μ 4 -O) 12 (TEOA) 6 (CH 3 COO) 16 (H 2 O) 8 ] 2+ ) were prepared. Experimental and theoretical studies on the magnetic properties of 1 and 1 a@SiO 2 reveal that encapsulation of one cluster into one silica nanosphere not only effectively decreases intermolecular magnetic interactions but also significantly increases the zero-field splitting effect of the outer layer Fe 3+ ions., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

To enable a comparison between a C-H...X hydrogen bond and a halogen bond, the structures of two fluorous-substituted pyridinium iodide salts have been determined. 4-[(2,2-Difluoroethoxy)methyl]pyridinium iodide, C 8 H 10 F 2 NO + ·I - , (1), has a -CH 2 OCH 2 CF 2 H substituent at the para position of the pyridinium ring and 4-[(3-chloro-2,2,3,3-tetrafluoropropoxy)methyl]pyridinium iodide, C 9 H 9 ClF 4 NO + ·I - , (2), has a -CH 2 OCH 2 CF 2 CF 2 Cl substituent at the para position of the pyridinium ring. In salt (1), the iodide anion is involved in one N-H...I and three C-H...I hydrogen bonds, which, together with C-H...F hydrogen bonds, link the cations and anions into a three-dimensional network. For salt (2), the iodide anion is involved in one N-H...I hydrogen bond, two C-H...I hydrogen bonds and one C-Cl...I halogen bond; additional C-H...F and C-F...F interactions link the cations and anions into a three-dimensional arrangement.

The salts 3-[(2,2,3,3-tetrafluoropropoxy)methyl]pyridinium saccharinate, C 9 H 10 F 4 NO + ·C 7 H 4 NO 3 S - , (1), and 3-[(2,2,3,3,3-pentafluoropropoxy)methyl]pyridinium saccharinate, C 9 H 9 F 5 NO + ·C 7 H 4 NO 3 S - , (2), i.e. saccharinate (or 1,1-dioxo-1λ 6 ,2-benzothiazol-3-olate) salts of pyridinium with -CH 2 OCH 2 CF 2 CF 2 H and -CH 2 OCH 2 CF 2 CF 3 meta substituents, respectively, were investigated crystallographically in order to compare their fluorine-related weak interactions in the solid state. Both salts demonstrate a stable synthon formed by the pyridinium cation and the saccharinate anion, in which a seven-membered ring reveals a double hydrogen-bonding pattern. The twist between the pyridinium plane and the saccharinate plane in (2) is 21.26 (8)° and that in (1) is 8.03 (6)°. Both salts also show stacks of alternating cation-anion π-interactions. The layer distances, calculated from the centroid of the saccharinate plane to the neighbouring pyridinium planes, above and below, are 3.406 (2) and 3.517 (2) Å in (1), and 3.409 (3) and 3.458 (3) Å in (2).

Neutralization of 4-[(2,2,3,3-tetrafluoropropoxy)methyl]pyridine with hydrohalo acids HX (X = Cl and Br) yielded the pyridinium salts 4-[(2,2,3,3-tetrafluoropropoxy)methyl]pyridinium chloride, C 9 H 10 F 4 NO + ·Cl - , (1), and 4-[(2,2,3,3-tetrafluoropropoxy)methyl]pyridinium bromide, C 9 H 10 F 4 NO + ·Br - , (2), both carrying a fluorous side chain at the para position of the pyridinium ring. Single-crystal X-ray diffraction techniques revealed that (1) and (2) are isomorphous. The halide anions accept four hydrogen bonds from N-H, ortho-C-H and CF 2 -H groups. Two cations and two anions form a centrosymmetric dimeric building block, utilizing complimentary N-H...X...H-Csp 3 connections. These dimers are further crosslinked, utilizing another complimentary Csp 2 -H...X...H-Csp 2 connection. The pyridinium rings are π-stacked, forming columns running parallel to the a axis that make angles of ca 44-45° with the normal to the pyridinium plane. There are also supramolecular C-H...F-C interactions, namely bifurcated C-H...F and bifurcated C-F...H interactions; additionally, one type II C-F...F-C halogen bond has been observed.