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Background and Objectives: Cigarette smoking has been reported as an independent risk factor for periodontitis. Tobacco toxins affect periodontal tissue not only locally but also systemically, leading to the deterioration and recurrence of periodontitis. However, the mechanism of cigarette smoke‐related periodontitis (CSRP) is unclear and thus lacks targeted treatment strategies. Quercetin, a plant‐derived polyphenolic flavonoid, has been reported to have therapeutic effects on periodontitis due to its documented antioxidant activity. This study aimed to evaluate the effects of quercetin on CSRP and elucidated the underlying mechanism. Methods: The cigarette smoke‐related ligature‐induced periodontitis mouse model was established by intraperitoneal injection of cigarette smoke extract (CSE) and silk ligation of bilateral maxillary second molars. Quercetin was adopted by gavage as a therapeutic strategy. Micro‐computed tomography was used to evaluate the alveolar bone resorption. Immunohistochemistry detected the oxidative stress and autophagy markers in vivo. Cell viability was determined by Cell Counting Kit‐8, and oxidative stress levels were tested by 2,7‐dichlorodihydrofluorescein diacetate probe and lipid peroxidation malondialdehyde assay kit. Alkaline phosphatase and alizarin red staining were used to determine osteogenic differentiation. Network pharmacology analysis, molecular docking, and western blot were utilized to elucidate the underlying molecular mechanism. Results: Alveolar bone resorption was exacerbated and oxidative stress products were accumulated during CSE exposure in vivo. Oxidative stress damage induced by CSE caused inhibition of osteogenic differentiation in vitro. Quercetin effectively protected the osteogenic differentiation of human periodontal ligament cells (hPDLCs) and periodontal tissue by upregulating the expression of Beclin‐1 thus to promote autophagy and reduce oxidative stress damage. Conclusion: Our results established a role of oxidative stress damage and autophagy dysfunction in the mechanism of CSE‐induced destruction of periodontal tissue and hPDLCs, and provided a potential application value of quercetin to ameliorate CSRP. [ABSTRACT FROM AUTHOR]

As the models for studying defected graphene, π‐conjugated systems containing heptagonal rings have attracted increasing interest due to their dynamic behaviors, electronic properties, aromaticity, and solid‐state packing. Doping heptagon‐containing π‐conjugated systems with boron not only makes π‐conjugated systems with the boron‐doped heptagonal ring have structural similarity to their all‐carbon analogues, but also could significantly change their electronic properties and intermolecular interactions. This review summarizes research on the different synthetic routes to access boron‐doped heptagons including borepins, azaborepins, and oxaborepins, with the emphasis on the structure‐property relationships at the molecular level. [ABSTRACT FROM AUTHOR]

One‐pot solvothermal reaction of 2‐aminopyridine and triethyl orthoformate with Ni(OAc)2 ⋅ 4H2O afforded a one dimensional (1D) nickel coordination polymer {[Ni(Dpyf′)] ⋅ MeOH}n (Dpyf′=C11H9N4−), 1, which has been structurally characterized by using single crystal X‐ray crystallography. Complex 1 can be considered as a potential heterogeneous catalyst for nitroaldol (Henry) reaction for C−C bond formation. [ABSTRACT FROM AUTHOR]

Electroanalytical, structural, and microanalytical techniques are combined to demonstrate the first clear and convincing case of electrochemical storage by Al‐ion intercalation in a Prussian blue analog host. In addition, a high power asymmetric capacitor using Al‐ion intercalation is demonstrated. Al, Fe, and Cu elemental maps of intercalated Al0.18 K0.02Cu[Fe(CN)6]0.7·3.7H2O obtained by transmission electron microscopy (TEM) energy‐dispersive X‐ray spectroscopy (EDX) area scan are shown. [ABSTRACT FROM AUTHOR]

Currently, because of the wide use of magnetic/metal hybrid materials in the field of surface-enhanced Raman scattering (SERS), magnetic fields (MFs) as a kind of surrounding environments of SERS substrates have been not ignored. And enormous attentions for the effect of MFs on SERS are very necessary. Our analysis from previous reports shows SERS signals are closely associated with MFs; yet the study of the exact effect of MFs on SERS is still in need of detail and broadening. In this work, we demonstrate that the use of Ni/Au microparticles (MPs) and Au hollow spheres (HSs) to study the effect of MFs on SERS signals. The experiments are preformed from three aspects, including the comparison of SERS signals of Ni/Au MPs with different Ms values, the comparison of SERS signals of Au HSs and Ni/Au MPs under different external MFs, and the comparison of SERS signals of single Au HS particle and single Ni/Au particle in the absence and presence of an external MF. Thereinto, under different external MFs from 0, 0.01, 0.02, 0.04 to 0.08 T, SERS signals of Au HSs and Ni/Au MPs are gradually weaker. According to the experiments, the weakening effect of MFs on SERS is confirmed. It is suggested that the weakening effect is originated from the blue-shift of surface plasmon resonance and the locking of charge-transfer from Au to probe molecules. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Ultrafast rate capability (>100 C current rates) and superior high‐rate cycling stability (>1500 cycles) in aqueous NaTi2(PO4)3/Na0.44MnO2 cells are demonstrated. Aqueous NaTi2(PO4)3/Na0.44MnO2 cell may be a candidate for safe, low cost, high power storage systems. [ABSTRACT FROM AUTHOR]

Review: 125 refs. [ABSTRACT FROM AUTHOR]

The synthesis is achieved by a highly efficient asymmetric synthesis of pentacycle (V). [ABSTRACT FROM AUTHOR]

The asymmetric unit of the title compound, C(17)H(16)O(4), contains two crystallographically independent mol-ecules with different absolute configurations.

In the title mol-ecule, C(10)H(7)ClO(3), the butyrolactone core, a furan-2(5H)-one, forms a dihedral angle of 59.21 (5)° with the benzene ring. In the crystal, two types of hydrogen bonds (O-H⋯O and C-H⋯Cl) link mol-ecules into infinite chains along the b axis. π-π contacts [centroid-centroid distances = 3.6359 (10) and 3.8776 (11) Å] link the chains into a three-dimensional network.

The title compound, C(16)H(12)ClNO(2), featuring a furan-2(5H)-one (γ-butyrolactone) core, contains two mol-ecules (A and B) in the asymmetric unit, with different dihedral angles between the central ring and the pendant phenyl and chloro-benzene rings [43.33 (8) and 20.16 (8)°, respectively, for A, and 47.79 (8) and 13.87 (8)°, respectively, for B]. In the crystal, the A mol-ecules are linked into [001] chains by single C-H⋯O inter-actions. The B mol-ecules also form [001] chains, but their relative orientations in the chains are quite different to those of the A mol-ecules so that adjacent B mol-ecules are linked by two C-H⋯O hydrogen bonds. Finally, C-H⋯O inter-actions and aromatic π-π stacking contacts [centroid-centroid separations = 3.754 (1) and 3.817 (1) Å] link the chains into a two-dimensional array parallel to (010).

In the title mol-ecule, C(21)H(20)N(2)O(4), the dihedral angle between the phenol ring and the isoindole-1,3-dione mean plane is 69.79 (6)°. The cyclo-hexane ring adopts a chair conformation. Weak inter-molecular O-H⋯O and O-H⋯N inter-actions feature as part of the crystal packing.

In the title mol-ecule, C(30)H(32)N(2)O(2), the two tolyl rings form dihedral angles of 65.8 (1) and 6.6 (1)° with the isoindole-1,3-dione mean plane. The cyclo-hexane ring adopts a chair conformation.

In the title heteronuclear Ni(II)-Ho(III) complex (systematic name: {μ-6,6'-dieth-oxy-2,2'-[ethane-1,2-diylbis(nitrilo-methyl-idyne)]diphenolato-1κ(4)O(1),O(1'),O(6),O(6'):2κ(4)O(1),N,N',O(1')}trinitrato-1κ(6)O,O'-holmium(III)nickel(II)), [HoNi(C(20)H(22)N(2)O(4))(NO(3))(3)], with the hexa-dentate Schiff base compartmental ligand N,N'-bis-(3-ethoxy-salicyl-idene)ethyl-enediamine (H(2)L), the Ho and Ni atoms are doubly bridged by two phenolate O atoms of the Schiff base ligand. The coordination of Ni is square-planar with the donor centers of two imine N atoms and two phenolate O atoms. The holmium(III) center has a tenfold -coordination environment of O atoms, involving the phenolate O atoms, two eth-oxy O atoms and two O atoms each from the three nitrates. Weak C-H⋯O and O⋯Ni [3.383 (4) Å] inter-actions generate a two-dimensional zigzag sheet.