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Glutamate-gated kainate receptors are ubiquitous in the central nervous system of vertebrates, mediate synaptic transmission at the postsynapse and modulate transmitter release at the presynapse1–7. In the brain, the trafficking, gating kinetics and pharmacology of kainate receptors are tightly regulated by neuropilin and tolloid-like (NETO) proteins8–11. Here we report cryo-electron microscopy structures of homotetrameric GluK2 in complex with NETO2 at inhibited and desensitized states, illustrating variable stoichiometry of GluK2–NETO2 complexes, with one or two NETO2 subunits associating with GluK2. We find that NETO2 accesses only two broad faces of kainate receptors, intermolecularly crosslinking the lower lobe of ATDA/C, the upper lobe of LBDB/D and the lower lobe of LBDA/C, illustrating how NETO2 regulates receptor-gating kinetics. The transmembrane helix of NETO2 is positioned proximal to the selectivity filter and competes with the amphiphilic H1 helix after M4 for interaction with an intracellular cap domain formed by the M1–M2 linkers of the receptor, revealing how rectification is regulated by NETO2. The authors report the structures of glutamate-gated kainate receptors in complex with NETO2 in both the resting and the desensitized states and reveal how kainate receptors in the brain are regulated by NETO2.

Sodium/proton exchanger 1 (NHE1) is an electroneutral secondary active transporter present on the plasma membrane of most mammalian cells and plays critical roles in regulating intracellular pH and volume homeostasis. Calcineurin B-homologous protein 1 (CHP1) is an obligate binding partner that promotes NHE1 biosynthetic maturation, cell surface expression and pH-sensitivity. Dysfunctions of either protein are associated with neurological disorders. Here, we elucidate structures of the human NHE1-CHP1 complex in both inward- and inhibitor (cariporide)-bound outward-facing conformations. We find that NHE1 assembles as a symmetrical homodimer, with each subunit undergoing an elevator-like conformational change during cation exchange. The cryo-EM map reveals the binding site for the NHE1 inhibitor cariporide, illustrating how inhibitors block transport activity. The CHP1 molecule differentially associates with these two conformational states of each NHE1 monomer, and this association difference probably underlies the regulation of NHE1 pH-sensitivity by CHP1., Sodium/proton exchanger 1 (NHE1) and its obligate binding partner Calcineurin B-homologous protein 1 (CHP1) regulate intracellular pH and volume homeostasis. Structures of the human NHE1-CHP1 complex offer insight into the regulation of NHE1 pH-sensitivity by CHP1 and into the interactions with NHE1 inhibitors.

Synchronously achieving high-capacity and high-rate sodium-ion storage is critical for large-scale energy stationary applications of sodium-ion batteries (SIB). Here we present a facile bottom-up strategy to covalently encapsulate sulfur chains into carbon-rich nanomaterials by knitting 3,4-ethylenedioxythiophene (EDOT) with external crosslinking reactants. Using a series of ex situ characterization studies, the synergistic effects of the covalent sulfur species (21.33 wt%) are demonstrated on both increasing reversible electrochemical active sites/structural defects and expanding interlayer spacing, which endow the elaborate anode material with a high capacity of 456 mA h g−1 @ 0.1 A g−1, a desirable rate capability as high as 253.2 mA h g−1 @ 5 A g−1 for sodium-ion storage, and an excellent long-cycling performance with almost no decay after 5000 cycles @ 5 A g−1. Significantly, dynamic investigation indicates that the sodium-ion storage process and transfer kinetics are closely related to the covalently encapsulated sulfur chains. This work furnishes a new and systemic insight into the rational design of sodium-ion anode materials, in which the covalent sulfur chemistry may play a crucial role in reaching the supreme performance of sodium-ion batteries.

This study was conducted to design an electrochemical sensor for detection of l-glutamate (L-Glu) and Aspartate (Asp), which contribute largely to the umami taste of beef. Using N, N'-diphenylthiourea (DPTU), polypyrrole (PPy), and polyvinyl chloride (PVC), a composite electrode (DPTU/PVC/PPy/Pt) was prepared for rapidly electrochemical detection of l-Glu and Asp. The surface morphology of the synthesized functionalized electrode was characterized by Field Emission Scanning Electron Microscopy (FESEM). Potentials of umami amino acids accounted for 97.8%, while six interferential amino acids existed. The linear correlation between the content of l-Glu and Asp in beef broth was studied under different treatment conditions. The sensor compared with an amino acid analyzer well detected the contents of l-Glu and Asp in beef broths, with a coefficient of 0.991 in Pearson correlation analysis and an accuracy of 88.9%. The proposed electrochemical sensor showed good concurrence with previously reported methods and was effectively employed for the quantification of l- Glu and Asp in beef. PRACTICAL APPLICATION: The sensor exhibits the good performance with high stability and high accuracy. And it is a potential sensing platform with good reproducibility, making the proposed method suitable and reliable for routine analysis of L-Glu and Asp in beef. This method was proved promising for quantitative detecting amino acids in beef.

Promoting the efficient utilization of both pores and heteroatoms remains a highly challenging endeavor, yet is of crucial significance to enhance the specific capacitance and energy density of carbon-based supercapacitors (SCs). Herein, a series of N,P-co-doped polypyrrole-derived carbon nanotubes (Px-ppyNTs) featuring a customized porous structure and doping level and intrinsically endowed with hollow cavities with tunable diameters were designed and synthesized via a strategic engineering approach. Benefiting from their regularly evolved physiochemical architecture, Px-ppyNTs served as a suitable platform to investigate the structure–property relationship between carbon-based materials and electrochemical capacitive behavior. Remarkably, the electrochemical surface area (ECSA) was proven to be critical to the reaction kinetics and resulted in the maximized utilization of both the porous structure and heteroatoms. The optimized ppyNT material with highest utilization of both the SSA (1853 m2 g−1) and inherent heteroatom doping (nitrogen: 7.2 at% and phosphorous: 2.5 at%) exhibited an extremely high specific capacitance of 438 F g−1 in 1.0 M H2SO4 and energy density of 25.3 W h kg−1 in 1.0 M Na2SO4. Furthermore, the calculated electric double layer capacitance (EDLC) contribution was maintained at as high as 203 F g−1 even across a wide scan rate in the range of 5 to 500 mV s−1. This work affords a promising electrode material for SCs and provides new insights into the critical role of ECSA in high-performance carbon-based SCs.

N-type voltage-gated calcium (CaV) channels mediate Ca2+ influx at the presynaptic terminals in response to action potential and play vital roles in synaptogenesis, neurotransmitter releasing, and nociceptive transmission. Here we elucidate a cryo-electron microscopy (cryo-EM) structure of the human CaV2.2 complex at resolution of 2.8 Å. This complex structure reveals how the CaV2.2, β1, and α2δ1 subunits are assembled. In our structure, the second voltage-sensing domain (VSD) is stabilized at a resting-state conformation, which is distinct from the other three VSDs of CaV2.2 as well as activated VSDs observed in previous structures of CaV channels. The structure also shows that the intracellular gate formed by S6 helices is closed, and a W-helix from the DII-III linker is determined to act as a blocking-ball that causes closed-state inactivation in CaV2.2. Collectively, our structure provides previously unseen structural insights into fundamental gating mechanisms of CaV channels.

Retinal degeneration diseases (RDDs) are common and devastating eye diseases characterized by the degeneration of photoreceptors, which are highly associated with oxidative stress. Previous studies reported that mitochondrial dysfunction is associated with various neurodegenerative diseases. However, the role of mitochondrial proteostasis mainly regulated by mitophagy and mitochondrial unfolded protein response (mtUPR) in RDDs is unclear. We hypothesized that the mitochondrial proteostasis is neuroprotective against oxidative injury in RDDs. In this study, the data from our hydrogen peroxide (H2O2)-treated mouse retinal cone cell line (661w) model of RDDs showed that nicotinamide riboside (NR)-activated mitophagy increased the expression of LC3B II and PINK1, and promoted the co-localization of LC3 and mitochondria, as well as PINK1 and Parkin in the H2O2-treated 661w cells. However, the NR-induced mitophagy was remarkably reversed by chloroquine (CQ) and cyclosporine A (CsA), mitophagic inhibitors. In addition, doxycycline (DOX), an inducer of mtUPR, up-regulated the expression of HSP60 and CHOP, the key proteins of mtUPR. Activation of both mitophagy and mtUPR increased the cell viability and reduced the level of apoptosis and oxidative damage in the H2O2-treated 661w cells. Furthermore, both mitophagy and mtUPR played a protective effect on mitochondria by increasing mitochondrial membrane potential and maintaining mitochondrial mass. By contrast, the inhibition of mitophagy by CQ or CsA reversed the beneficial effect of mitophagy in the H2O2-treated 661w cells. Together, our study suggests that the mitophagy and mtUPR pathways may serve as new therapeutic targets to delay the progression of RDDs through enhancing mitochondrial proteostasis.

Dorzagliatin, a novel glucokinase (GK) activator targeting both pancreatic and hepatic GK, is currently in late-stage clinical development for treatment of type 2 diabetes (T2D). For the optimization of dosing regimens to ensure adequate safety and efficacy, it is critical to have a deep understanding of pharmacokinetic (PK) and pharmacodynamic (PD) profiles of the drug in various targeting patient populations, considering the fact that T2D adversely affects a vast patient population who often times also suffer from a wide range of comorbidities including severe liver and/or kidney damage. Since drug efficacy seems to be closely related to unbound drug concentrations at the site of action, therefore, the determination of plasma unbound concentrations/fractions of dorzagliatin is of crucial importance, especially when performing the PK/PD assessment in those special populations. In the current study, a method was developed and validated for determining the unbound fraction (fu) of dorzagliatin in human plasma by using equilibrium dialysis for the separation of the bound and unbound drug, and LC-MS/MS for subsequent quantification. We have successfully addressed two widely recognized challenges for determination of the fu, i.e., the lack of knowledge on the "true fu" and the difficulty in assessing the accuracy and reproducibility of the measurement. Using this method, a 0.2 mL aliquot of human plasma samples were first dialyzed against 0.35 mL of phosphate buffered saline buffer at 37 °C for 5 h in the equilibrium dialysis device to separate the unbound dorzagliatin. Afterwards, post-dialysis samples were extracted by protein precipitation using acetonitrile. Separation of dorzagliatin and potential interferences were achieved using a Gemini C18 column coupled with gradient elution. Subsequent detection was carried out on tandem mass spectrometer operated by multiple reaction monitoring in positive mode using electrospray ionization. The standard curve over the concentration range of 0.125-250 ng/mL exhibits good linearity. The method was fully validated meeting the requirements in current bioanalytical guidance and was successfully applied in a clinical PK study of dorzagliatin in healthy volunteers and patients with renal function impairment. Method reproducibility was demonstrated in incurred sample reanalysis. With demonstrated accuracy, stability and reproducibility, reliable analytical results were obtained from clinical samples for PK/PD interpretation, providing valuable insight for the development of dorzagliatin.

Two new Cd(II) coordination compounds, namely [Cd(Htci)(biimpy)]n (1) and [Cd3(tci)2(biimpy)2(H2O)2]n (2) (H3tci = tri(2-carboxyethyl)isocyanuric acid, biimpy = 2,6-bis(1-imdazoly)pyridine) were synthesized under solvothermal conditions via tuning the pH of reaction mixture. Single crystal X-ray diffraction analyses revealed that compound 1 features a 2D layer structure that further extended into a 3D supramolecular framework directed by hydrogen bonds, and compound 2 features a 3D pillar-layered framework. In these two compounds, the organic carboxylate ligands adopt two distinct conformations: cis-cis-trans for 1 and cis-cis-cis for 2. The luminescent properties investigations indicated that both 1 and 2 emit intense luminescence at room temperature.

A new Pb(II) coordination polymer, namely [Pb2(bptc)(DMA)]n (1, H4bptc = biphenyl-3,3′,5,5′-tetracarboxylic acid, DMA = N, N′- dimethylacetamide), has been synthesized by the combination of H4bptc with Pb(NO3)2 under solvothermal conditions. Single crystal X-ray diffraction analysis revealed that compound 1 features a 3D framework based on tetranuclear [Pb4(COO)6] subunits, and topological analysis revealed that compound represents a binodal (4, 8)-connected scu-type topological network with the point symbol of {416,612}{44,62}2. Luminescence studies indicated that 1 and 1’ (1′ represents the desolvated samples) showed intense yellow emissions. Significantly, 1′ exhibited sensitive luminescence sensing for CS2 solvent molecules at a low concentration.

A polyvinyl chloride (PVC) membrane sensor was developed to accurately detect beef taste quality grades. The beef taste was identified by the Fisher discriminant and verified by sensory evaluation. The PVC membrane sensor with the maximum open circuit potential (OCP) value and excellent performance was composed of 0.4 mL of dibutyl phthalate (DBP), 0.25 mL of lauryl ether phosphate, 3.6 mg of magnesium stearate and 6 mg of thermoplastic polyurethanes (TPU). Texture analyzer tests showed that the membranes showed desired physical properties, and the elasticity, viscosity and cohesion of the PVC membrane sensor were 4.74 mm, 2.17 mJ and 1.89 respectively. Scanning electron microscopy (SEM) showed the electrode immersed for 6 h without separation with PVC membrane. The coefficient of variation was less than 10% with a storage period of 7 months. Sensory evaluation showed that the beef sensory rated grades array determination by the Fisher discriminant method to verify the sensitivity of ammonia-sensitive substance-modified PVC membrane sensor had an accuracy of 93.3%.

Summary: N-type voltage-gated calcium (CaV) channels mediate Ca2+ influx at presynaptic terminals in response to action potentials and play vital roles in synaptogenesis, release of neurotransmitters, and nociceptive transmission. Here, we elucidate a cryo-electron microscopy (cryo-EM) structure of the human CaV2.2 complex in apo, ziconotide-bound, and two CaV2.2-specific pore blockers-bound states. The second voltage-sensing domain (VSD) is captured in a resting-state conformation, trapped by a phosphatidylinositol 4,5-bisphosphate (PIP2) molecule, which is distinct from the other three VSDs of CaV2.2, as well as activated VSDs observed in previous structures of CaV channels. This structure reveals the molecular basis for the unique inactivation process of CaV2.2 channels, in which the intracellular gate formed by S6 helices is closed and a W-helix from the domain II–III linker stabilizes closed-state inactivation. The structures of this inactivated, drug-bound complex lay a solid foundation for developing new state-dependent blockers for treatment of chronic pain.

Presented here is a new Zn(II) compound, namely [Zn4(btec)2(DMA)3]n (1 represents this compound, H4btec = 1,2,4,5-benzenetetracarboxylic acid, DMA = N,N′-dimethylacetamide). This compound crystallizes in orthorhombic Pbca space group with a = 19.053(2) A, b = 18.8010(6) A, c = 22.9434(8) A, α = β = γ = 90°, and Z = 8. Single crystal X-ray diffraction analysis reveals that compound 1 features a three-dimensional (3D) framework based on two different dinuclear [Zn2(COO)3] subunits. In addition, the solid-state luminescent property of 1 and the gas sorption properties of the desolvated 1a were also investigated.

A new Zn(II) metal–organic framework, namely [Zn3(3-atrz)2(4-atrz)2(SO4)2]n (1 3-atrz = 3-amino-1,2,4-triazole, 4-atrz = 4-amino-1,2,4-triazole), has been solvothermally synthesized via the reactions of ZnSO4·7H2O and two different kinds of isomorphic aminotriazole ligands (3-atrz and 4-atrz). Single crystal X-ray diffraction analysis revealed that compound 1 features a trinuclear [Zn3(3-atrz)2(4-atrz)2(SO4)2] subunits based 3D framework with 6-connected pcu topology. In the 3D framework of 1, 3-atrz ligand displays a μ3-κN1, κN2, κN3 coordination mode and 4-atrz ligand displays a μ2-κN1, κN2 coordination mode. The luminescent properties investigation indicated that compound 1 shows strong luminescence at room temperature and high selectivity and sensitivity for Fe3+ ion in aqueous solution.

A new heterometallic-organic framework, namely [CuCa(tdc)2(DMF)]n (1 H2tdc = 2,5-thiophenedicarboxylic acid, DMF = N,N’-dimethylformamide), has been successfully obtained through the solvothermal reactions of CuCl2, Ca(NO3)2, and H2tdc. Single-crystal structural analysis reveals that compound 1 features a 3D framework with the irl topology. Compound 1 has potential unsaturated metal sites after the removal of the coordinated DMF molecules, so it exhibits excellent catalytic activity for the diethylzinc addition to benzaldehyde.

Via the solvothermal reactions of Cd(NO3)2 and H2L, a new Cd(II) compound, namely [Cd(L)]n (1 H2L = 5-CH2OH-isophthalic acid), was obtained. This compound was further characterized by single-crystal X-ray diffraction analysis, elemental analyses, and powder X-ray diffraction analyses. Single-crystal X-ray diffraction analysis reveals that compound 1 features a 3D framework based on dinuclear [Cd2(COO)2] subunits. Topological analysis reveals that compound 1 represents a new (4, 8)-connected topology. In addition, the luminescent property of 1 was also investigated at room temperature.

A new Cd(II) compound, namely [Cd3(BTC)2(e-urea)4]n (1 H3BTC = 1,3,5-benzenetricarboxylic acid, e-urea = ethylene urea), has been synthesized by the urothermal reactions of 1,3,5-benzenetricarboxylic acid and Cd(NO3)2 and further characterized by elemental analysis, powder X-ray diffraction, and single-crystal X-ray diffraction. Compound 1 features a three-dimensional (3D) framework based on trinuclear [Cd3(COO)6(e-urea)2] subunits. By viewing BTC3−, trinuclear [Cd3(COO)6(e-urea)2] subunits as 3- and 6-connected nodes, respectively, the whole framework of 1 can be simplified into a rtl-type topological network. Moreover, the thermal stability and luminescent property of compound 1 were also investigated.

A new Cd(II) coordination polymer, namely {Cd3(pbdc)3(e-murea)(DMF)}n·n(e-murea) (1, H2pbdc = terephthalic acid, e-murea = 1,3-dimethyl-2-imidazolidinone, DMF = N,N'-dimethylformamide), has been successfully synthesized via the urothermal reactions of Cd(II) ions and terephthalic acid ligand. Single-crystal X-ray structural analysis reveals that 1 features a two-dimensional layer framework with rod-shaped hexanuclear {Cd6(COO)12} clusters as building subunits. In addition, the luminescent property of 1 was also studied at room temperature.

A new Cd(II) coordination polymer, namely [Cd(L)(H2O)]n (1, H2L = 5-(pyridin-3-ylmethoxy)-isophthalic acid), has been synthesized through hydrothermal reactions of Cd(NO3)2 and H2L. The title compound crystallizes in triclinic, space group P-1 with a = 8.450(3), b = 8.941(3), c = 10.057(3) A, α = 70.291(8)°, β = 67.339(10)°, γ = 82.575(11)° V = 660.1(4) A3. Single-crystal X-ray diffraction analysis reveals that compound 1 features a 3D supramolecular framework based on (3,6)-connected 2D sheets.

A new heterometallic poly(dihydrate-one and a half terephthalate–cadmium calcium) coordination polymer, namely [CdCa(pdc)1.5(H2O)2]n (1, H2pdc = terephthalic acid), has been successfully obtained by the solvothermal reactions of H2pdc, Cd(NO3)2·4H2O and Ca(NO3)2·4H2O. Single crystal X-ray diffraction analysis reveals that compound 1 features a 3D porous framework based on 1D chain subunits. Moreover, compound 1 is luminescent and exhibits high adsorption capacities for H2, CH4 and CO2 at room temperature.

Reported here is a new Zn(II) compound, namely [Zn 2 (tdc) 2 (MA)] n (H 2 tdc = 2,5-thiophenedicarboxylic acid, MA = melamine), which has been constructed by the self-assembly reaction of Zn(NO 3 ) 2 , H 2 tdc and MA under solvothermal conditions. Single crystal X-ray diffraction analysis reveals that this compound features a 3D porous framework with 6-connected pcu topology. Notably, this compound exhibits high CO 2 sorption capacity and high sorption selectivity for CO 2 over N 2 at 298 K.

A bio-based Mg(OH)2@tin phytate@zinc tannate (MH@PASn@TAZn) composite was synthesised via layer-by-layer assembly method. Chemical bonds formed by chelating metal ions with phytic acid and tannic acid were involved in this synthesis. MH@PASn@TAZn was then incorporated into PVC and its effects on flame retardancy, smoke suppression and mechanical properties were investigated. The core-shell structure and binding states between each layer (Mg–O–P, P–O–C) of the composite were examined. The limiting oxygen index (LOI) and cone calorimeter test results showed that the addition of 10 ph MH@PASn@TAZn effectively enhanced the flame retardancy and smoke suppression of PVC. The LOI value of the 10 ph MH@PASn@TAZn-incorporated PVC sample increased to 30.3% because of the combination of the gas dilution effect of vapor generated by the degradation of MH and synergistic catalytic carbonisation of PASn and TAZn. The second peak heat release rate, second peak smoke production rate and total smoke production of PVC/MH@PASn@TAZn composite decreased by 40.8%, 72.2% and 35.2%, respectively. The increase in the interfacial contact area of PASn and the enhancement of interfacial interaction of TAZn significantly improved the tensile strength, elongation at break, and impact strength of PVC. This study presents a promising approach to synthesise flame-retardant PVC with excellent smoke suppression and mechanical properties.

Two new Zn(II) compounds, namely [(CH3)2NH2]2n[Zn3(bpt)2(datrz)2]n (1) and [(CH3)2NH2)]n[Zn2(bptc)(datrz)]n·n(H2O) (2) (H3bpt = biphenyl-3,4′,5-tricarboxylic acid, H4bptc = biphenyl-3,3′,5,5′-tetracarboxylic acid, Hdatrz = 3,5-diamino-1,2,4-triazole), have been obtained by the self-assemble reactions of Zn(NO3)2, 3,5-diamino-1,2,4-triazole, aromatic polycarboxylate ligands under solvothermal conditions. Single crystal X-ray structural analyses reveal that both compounds display three-dimensional (3D) frameworks. Compound 1 features a trinodal (3, 4, 6)-connected topological network with the point symbol of {4.62}2{4.64.8}{46.64.85}. Compound 2 displays a binodal (4, 6)-connected topological network with the point symbol of {32.62.72}{34.42.64.75}. In addition, the thermal stabilities and luminescent properties of compounds 1 and 2 were also investigated in the solid state at room temperature.

A new heterometallic compound, namely [CdBa(tdc)2(DMF)2(H2O)]n (1 H2tdc = 2,5-thiophenedicarboxylic acid, DMF = N,N′-dimethylformamide), has been solvothermally synthesized and characterized by elemental analysis and single crystal X-ray diffraction. Compound 1 features a complicated three-dimensional (3D) framework based on heterometallic -{Cd-COO-Ba}n- inorganic chains. In addition, the luminescent properties of this compound were also investigated at room temperature.

Two bromo-substituted Schiff bases 5-bromo-2-methoxy-4-(p-tolyliminomethyl)phenol (1) and 2-bromo-6-[(6-methylpyridin-2-ylimino)methyl]phenol (2) are prepared and characterized by elemental analysis, 1H and 13C NMR, and single crystal X-ray diffraction. Compound 1 crystallizes in the triclinic space group P\(\bar 1\) with unit cell dimensions a = 6.228(1) A, b = 10.929(2) A, c = 21.312(2) A, α = 104.230(2)°, β = 91.780(2)°, γ = 90.890(2)°, V = 1405.0(4) A3, Z = 4, R1 = 0.0359, and wR2 = 0.0830. Compound 2 crystallizes in the monoclinic space group P21/c with unit cell dimensions a = 8.180(2) A, b = 12.011(3) A, c = 12.843(3) A, β = 106.263(2)°, V = 1211.4(4) A3, Z = 4, R1 = 0.0364, and wR2 = 0.0889. X-ray diffraction indicates that the Schiff base molecules of the compounds display trans configuration with respect to the C=N double bonds. The crystal structures of the compounds are stabilized by hydrogen bonds and weak π•••π interactions.

The aroylhydrazone Schiff base ligand [N'-(5-chloro-2-hydroxybenzylidene)-4-hydroxybenzohydrazide (H2L) and salicylhydroxamic acid (Hsha) reacting with VO(acac)2 in methanol gave the complex [VOL(sha)]·3H2O. The complex was characterized by elemental analyses and IR spectroscopic method in the solid state. Single crystal X-ray analysis was performed, which indicated that the complex is a mononuclear compound. The V atom in the complex is in an octahedral geometry. VIV in VO(acac)2 was oxidized to VV in the complex by aerial oxygen during the synthesis and crystallization. Thermal behavior of the complex was studied. Antibacterial activity of the aroylhydrazone ligand and the complex has been studied on the bacteria strains B. subtilis, E. coli, and S. aureus.

A green and economical catalyst system, 4-OH-TEMPO/TCQ/TBN/HCl, for the aerobic oxidation of a broad range of primary and secondary alcohols to the corresponding carbonyl compounds has been developed. These reactions proceed without transition-metals under mild conditions with excellent yields.

Two cadmium(II) coordination polymers, namely [Cd3(bpt)2(DMA)2]n (1) and [Cd2(bpt)(btz)(DMF)]n (2) (H3bpt = biphenyl-3,4′,5-tricarboxylic acid, Hbtz = 1H-benzotriazole, DMA = N,N-dimethylacetamide; DMF = N,N-dimethylformamide), were solvothermally synthesized and structurally characterized by single-crystal X-ray diffraction. Compound 1 displays a 3D framework based on trinuclear {Cd3(COO)4} subunits and can be simplified into a (4,8)-connected topological network by viewing bpt3– ligands and trinuclear {Cd3(COO)4} units as 4-, 8-connected nodes, respectively. Compound 2 also displays a 3D framework but based on 1D chain subunits controlled by carboxylate groups and btz– ligands. In addition, the thermal stabilities and luminescent properties of compounds 1 and 2 were also investigated.

The zinc(II) complex [Zn(FA)(datrz)2]n (1) (H2FA = fumaric acid, Hdatrz = 3,5-diamino-1,2,4-triazole) was synthesized by solvothermal reaction of H2FA, Hdatrz, and Zn(NO3)2. Single crystal X-ray structure analysis revealed that compound 1 features a three-dimensional (3D) porous framework, which represents a 6-connected pcu topological network. Thermogravimetric analysis (TGA) indicates that compound 1 has high thermal stability. The permanent porosity of 1 was investigated by the adsorption of N2 and CO2. The amino groups of 1 enable high CO2 adsorption capacity.

Testosterone can affect cardiovascular disease, but its effects on mitochondrial dynamics in the post-infarct myocardium remain unclear. To observe the effects of testosterone replacement, a rat model of castration-myocardial infarction (MI) was established by ligating the left anterior descending coronary artery 2 weeks after castration with or without testosterone treatment. Expression of mitochondrial fission and fusion proteins was detected by western blot and immunofluorescence 14 days after MI. Cardiac function, myocardial inflammatory infiltration and fibrosis, cardiomyocyte apoptosis, mitochondrial microstructure, and ATP levels were also assessed. Compared with MI rats, castrated rats showed aggravated mitochondrial and myocardial insults, including mitochondrial swelling and disordered arrangement; loss of cristae, reduced mitochondrial length; decreased ATP levels; cardiomyocyte apoptosis; and impaired cardiac function. Results of western blotting analyses indicated that castration downregulated peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1A) and mitofusin 2, but upregulated dynamin-related protein 1. The results were also supported by results obtained using immunofluorescence. However, these detrimental effects were reversed by testosterone supplementation, which also elevated the upstream AMP-activated protein kinase (AMPK) activation of PGC1A. Thus, testosterone can protect mitochondria in the post-infarct myocardium, partly via the AMPK–PGC1A pathway, thereby decreasing mitochondrial dysfunction and cardiomyocyte apoptosis. The effects of testosterone were confirmed by the results of ELISA analyses.

A new zinc(II) coordination polymer, namely [Zn3(Hbptc)2(e-urea)2]n·2n(e-urea) (1) (H4bptc = biphenyl-3,3′,5,5′-tetracarboxylic acid, e-urea = ethyleneurea), was assemblied by H4bptc and Zn(NO3)2·6H2O under urothermal conditions. Single crystal X-ray diffraction analysis reveals that compound 1 features a 3D complicated framework with 1D nanotubes, which are occupied by the coordinated and lattice e-urea molecules. Compound 1 displays strong luminescence emission ability and high thermal stability. In addition, the gas storage properties of N2, H2, and CO2 for the desolvated framework of 1a were also investigated.

It is widely believed that the dehydrogenation of organic compounds is a thermodynamically unfavorable process, and thus requires stoichiometric oxidants such as dioxygen and metal oxides or sacrificial hydrogen acceptors to remove the hydrogen from the reaction mixture to drive the equilibrium towards the products. Here we report a previously unappreciated combination of common commercial Pd/C and H2 which dehydrogenates a wide range of substituted cyclohexanones and 2-cyclohexenones to their corresponding phenols with high isolated yields, with H2 as the only byproduct. The reaction requires no oxidants or hydrogen acceptors because instead of removing the generated hydrogen with oxidants or hydrogen acceptors, we demonstrated it can be used as a cocatalyst to help power the reaction. This method for phenol synthesis manifests a high atom economy, and is inherently devoid of the complications normally associated with oxidative dehydrogenations.

Three new coordination polymers, namely [Zn(tdc)(impy)]n (1), [Zn(4,4′-sdb)(impy)]n·1.5n(H2O) (2) [Zn(D-cam)(impy)]n (3) (H2tdc = 2,5-thiophenedicarboxylic acid, 4,4′-H2sdb = 4,4′-sulfonyldibenzoate, D-H2cam = D(+)-camphoric acid, impy = 2,6-bis(1-imdazoly)pyridine), have been synthesized under hydrothermal conditions. Structural analysis indicates that these three compounds all display 2D layer structures. Compound 1 presents a 3-connected hcb topology with the point symbol of {63}, compound 2 presents another 3-connected topological network with the point symbol of {82.10}, and compound 3 presents a 4-connected sql topology with the point symbol of {44.62}. Their thermal and luminescent properties are also investigated.

Presented here is a new heterometallic coordination polymer, namely [ZnCa(btec)(H2O)2]n (1 H4btec = 1,2,4,5-benzenetetracarboxylic acid), which was successfully synthesized via the hydrothermal reactions of H4btec, Zn(NO3)2 and CaCl2. Single crystal X-ray structural analysis reveals that compound 1 features a 3D inorganic–organic hybrid framework, which can be simplified into a (4,8)-connected scu topological network by viewing Zn(II) ions, Ca(II) ions, btec4− ligands as 4-, 4-, and 8-connected nodes, respectively. Moreover, the luminescent properties of compound 1 and the desolvated samples were also investigated at room temperature.

Despite the importance of testosterone as a metabolic hormone, its effects on myocardial metabolism in the ischemic heart remain unclear. Myocardial ischemia leads to metabolic remodeling, ultimately resulting in ATP deficiency and cardiac dysfunction. In the present study, the effects of testosterone replacement on the ischemic heart were assessed in a castrated rat myocardial infarction model established by ligating the left anterior descending coronary artery 2 weeks after castration. The results of real-time PCR and Western blot analyses showed that peroxisome proliferator-activated receptorα(PPARα) decreased in the ischemic myocardium of castrated rats, compared with the sham-castration group, and the mRNA expression of genes involved in fatty acid metabolism (the fatty acid translocase CD36, carnitine palmitoyltransferase I, and medium-chain acyl-CoA dehydrogenase) and glucose transporter-4 also decreased. A decline in ATP levels in the castrated rats was accompanied by increased cardiomyocyte apoptosis and fibrosis and impaired cardiac function, compared with the sham-castration group, and these detrimental effects were reversed by testosterone replacement. Taken together, our findings suggest that testosterone can modulate myocardial metabolic remodeling by upregulating PPARαafter myocardial infarction, exerting a protective effect on cardiac function.

A green and economical catalyst system, 4-OH-TEMPO/TCQ/TBN/HCl, for the aerobic oxidation of a broad range of primary and secondary alcohols to the corresponding carbonyl compounds has been developed. These reactions proceed without transition-metals under mild conditions with excellent yields.

A new method using a column packed with graphene as sorbent was developed for the preconcentration of trace amounts of cadmium (Cd) prior to its determination by flame atomic absorption spectrometr...