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Recently, scientists have reported a range of chiral fluorescence materials or chiral composites that can emit circularly polarized luminescence. Herein, two achiral metal-organic colloidal solutions were studied, showing active circularly polarized luminescence, which is observed in vortex stirring. The absolute values for glum are 0.05 and 0.03 and the plus or minus sign of glum depends on the colloidal structure and stirring direction, which make the property easy to manipulate. Further, the host-guest interaction study suggests both electrostatic interactions and coordination bonding may influence the chiroptical property from the colloidal solution to the guest molecule. Rhodamine 6G and its carboxylic acid derivative exhibit good quantum yields and acceptable glum values in the colloidal solution. more...

Purpose To evaluate the effect of a high-fat diet on the pharmacokinetics and safety of flumatinib mesylate tablets in healthy Chinese subjects. Methods This study was a randomized, open-label, single-dose, two-period crossover trial in which subjects were randomly assigned to take 400 mg of flumatinib mesylate after a high-fat diet or a fasted state. After a 14-day washout period, the two groups were administered flumatinib mesylate under opposite conditions. Blood samples were collected at baseline 0 and 0.5, 1, 1.5, 2, 2.5, 3, 4, 5, 6, 8, 10, 12, 24, 48, 72, and 96 h, respectively. Plasma concentrations of flumatinib and its metabolites (M1 and M3) were analyzed using liquid chromatography-mass spectrometry. Pharmacokinetic parameters were calculated using the non-compartmental module of the Phoenix WinNonlin Version 7.0 software. BE module of WinNonLin was used for statistical analysis of AUC0–t, AUC0–∞ and Cmax in plasma. Results Twelve healthy subjects, half male and half female, were enrolled. One subject withdrew due to a treatment-emergent adverse event. Eleven subjects were administered drugs on fasting and 12 were administered drugs after a high-fat diet. On high-fat diet/fasting, the least square geometric mean (LSGM) ratios of flumatinib, M1, M3, and their 90% confidence interval (CI) were as follows: for flumatinib, Cmax, AUC0–t and AUC0–∞ were 281.65% (225.80–351.31%), 167.43% (143.92–194.79%), and 166.87% (143.47–194.09%); for M1, Cmax, AUC0–t, and AUC0–∞ were 188.59% (145.29–244.79), 163.94% (149.11–180.24%), and 164.48% (150.36–179.94%); for M3, Cmax, AUC0–t, and AUC0–∞ were 63.47% (54.02–74.57%), 85.23% (74.72–97.22%), and 96.73% (86.63–108.02%). Conclusion Among the subjects, oral administration of 400 mg of flumatinib was safe and well tolerated. High-fat diet significantly increases the exposure to flumatinib, therefore, fasting may be recommended. Clinical trial registration The study was registered at chictr.org Identifier: ChiCTR-IIR-17013179. more...

Purpose This is the first study to compare the pharmacokinetics of QL1101, a proposed bevacizumab biosimilar, with Avastin® sourced from Roche Diagnostics GmbH. Methods In this double-blind, single-dose, parallel-group study, healthy male subjects were randomized 1:1 to receive QL1101 or Avastin® 3 mg/kg intravenously. Pharmacokinetic assessments were conducted for 85 days, with additional safety and immunogenicity assessments until day 90. Primary study endpoints were area under the concentration–time curve (AUC) from time zero to infinity (AUC0–∞), AUC from time zero to the last quantifiable concentration (AUC0–last), and maximum serum concentration (Cmax). Pharmacokinetic equivalence was shown if the 90% confidence intervals (CIs) of the geometric mean ratios (GMRs) of the C0–max, AUC0–last, and AUC0–∞ were within the predefined bioequivalence margin of 80–125.00%. Results A total of 82 subjects were randomized to the following groups: 42 to QL1101 and 40 to Avastin®. The 90% CIs of the GMRs of AUC0–∞, AUC0–last, and Cmax of QL1101 and Avastin® were (97.8%, 107.0%), (94.5%, 106.9%), and (94.1%, 107.3%), respectively, which were all within the bioequivalence margin. The incidence of adverse events was 90.5% and 95.0% in the QL1101 and Avastin® groups, respectively. Mean serum concentration–time profiles, secondary pharmacokinetic parameters, and safety and immunogenicity profiles were comparable across the two treatment groups. Conclusions The study demonstrated the pharmacokinetic equivalence of QL1101 to Avastin®. QL1101 (3 mg/kg, iv) is safe and tolerable in healthy Chinese subjects. These data support the further clinical evaluation of QL1101 as a bevacizumab biosimilar. more...

Chiral compounds are known to be important not only because they are the fundamental components of living organisms, but also for their unique chiroptical properties. In recent years, scientists have fabricated several chiral organic supramolecular aggregates by using chiral physical fields, such as vortex flow. Herein, the relationship between dynamic chiroptical properties and rheological nature is discussed, suggesting the shear thinning properties of non-Newtonian fluids might help colloidal particles adopt a chiral arrangement in vortices. Furthermore, the storage modulus of colloids could be increased by adding a linking agent, which successfully kept the dynamic chiroptical properties in the static state. Moreover, the salt effect on the host-guest interaction involved in the colloids was studied, the results suggested a significant enhancement of the transferred dynamic circular dichroism for the achiral guest molecule. more...

Neonatal pancreatic cell clusters (NPCCs) are potential tissues for the treatment of diabetes. Different from adult cells, they continuously proliferate and differentiate after transplantation. In this study, we utilized magnetic resonance imaging (MRI) to detect and monitor implanted NPCCs. NPCCs were isolated from one-day-old neonatal pigs, cultured for three days, and then incubated overnight with the contrast agent chitosan-coated superparamagnetic iron oxide (CSPIO) nanoparticles. In vitro, Prussian blue staining and MR scans of CSPIO-labeled NPCCs were performed. In vivo, we transplanted 2000 CSPIO-labeled NPCCs under the kidney capsule of nondiabetic nude mice. Recipients were scanned with 7.0T MRI. Grafts were removed for histology with insulin and Prussian blue staining. After being incubated overnight with CSPIO, NPCCs showed positive iron staining and appeared as dark spots on MR scans. After transplantation of CSPIO-labeled NPCCs, persistent hypointense areas were observed at recipients’ implant sites for up to 54 days. Moreover, histology showed colocalization of the insulin and iron staining in 15-, 51- and 55-day NPCC grafts. Our results indicate that transplanted NPCCs survived and differentiated to β cells after transplantation, and that MRI is a useful tool for the detection and monitoring of CSPIO-labeled NPCC grafts. more...

Chinese excellent traditional culture is the toughest spiritual bond and the most prominent spiritual identity of the Chinese nation. It is the root and soul of every Chinese. In the new era, in order to further inherit and develop the excellent traditional culture of the Chinese nation, it is necessary to adhere to the dialectical inheritance of the excellent traditional culture of the Chinese nation, creative transformation and innovative development, so as to continuously promote the modernization of the excellent traditional culture of the Chinese nation. more...

Crystallization of two enantiomers Δ-1 and Λ-1 was achieved by using an achiral flexible ligand H4L (2,2′-[1,2-ethanediylbis[(hydroxyethylimino)methylene]]bis[6-methoxy-4-methyl-phenol]). The absol... more...

Cerium ferrite (CeFeO3) thin films doped with vanadium (V:CeFeO3) were grown on SiO2 quartz glass and -oriented SrTiO3 (STO) crystal substrates by the radio-frequency magnetron sputtering method in this study. The effects of crystallization, substrate, and V-doping on the quality, the magnetic property and the magneto-optical property of as-prepared films are investigated. V:CeFeO3 film grown on STO substrate has better crystallinity and has better lattice integrity due to the higher lattice matching between substrate and film. The magnetic hysteresis loop and the magnetic circular dichroism spectra show that the magnetization strength and the magneto-optical properties of V:CeFeO3 films have the significant anisotropy. Moreover, V-doping and the stress lead to the change in easy magnetization direction of film. It shows that the perovskite B-site doping with transition-metal ion has significant influence on the magnetic and the magneto-optical properties of CeFeO3 thin films. more...

A novel stilbene-based salicylhydrazone compound {systematic name: (E)-4,4′-(ethene-1,2-diyl)bis[(N′E)-N′-(2-hydroxybenzylidene)benzohydrazide] dimethyl sulfoxide disolvate, C30H24N4O4·2C2H6OS or L·2DMSO} was synthesized and characterized by single-crystal X-ray diffraction, powder X-ray diffraction and luminescence spectroscopy. The title compound crystallizes in the monoclinic space group P21/c, with half a symmetry-independent L molecule and one dimethyl sulfoxide (DMSO) solvent molecule in the asymmetric unit. The L molecule adopts an almost planar structure, with a small dihedral angle between the planes of the stilbene and salicylhydrazone groups. There are multiple π–π stacking interactions between adjacent L molecules. The DMSO solvent molecules act as proton donors and acceptors, forming hydrogen bonds of various strengths with the L molecules. In addition, the geometry optimization of a single molecule of L and its luminescence properties either in solution, as a solvated solid or as a desolvated solid were studied. The compound shows an aggregation-induced emission (AIE) effect and exhibits switchable luminescence colouration in the solid state by the simple removal or re-addition of the DMSO solvent. more...

To detect and trace transplanted β-cells by magnetic resonance imaging (MRI), we conjugated manganese magnetism-engineered iron oxide (MnMEIO) nanoparticles with exendin-4 (MnMEIO-Ex4) which can specifically bind glucagon-like peptide-1 receptors on β-cells. Incubation of MIN6 β-cells and MnMEIO showed MnMEIO with iron content 5-40 μg/mL had no adverse effect on MIN6 β-cells assessed by the fluorescence of propidium iodide and insulin secretory response to glucose. Positive iron staining by Prussian blue was found in the MIN6 loaded with MnMEIO-Ex4 but not with MnMEIO. A transmission electron microscope with elementary mapping of iron and manganese demonstrated MnMEIO-Ex4 nanoparticles distributed in the cytoplasm of MIN6 β-cells. In vitro 7.0 T MR image showed loss of intensity in MIN6 β-cells loaded with MnMEIO-Ex4 but not with MnMEIO. With addition of poly-L-lysine, only MIN6 β-cells incubated with MnMEIO-Ex4 but not MnMEIO stimulated proinsulin mRNA expression and insulin secretion. On day 1, 6, 15, 22 and 29 after syngeneic transplantation of 700 C57/B6 mouse islets labeled with MnMEIO-Ex4, the islet graft under left kidney capsule could be visualized on 7.0 T MRI as persistent hypodense areas (indicated by arrows in Figure). Our results indicate MnMEIO-Ex4 nanoparticles are safe and effective for the detection and monitoring of islet grafts by MRI. Disclosure J. Juang: None. C. Shen: None. J. Wang: None. S. Wu: None. C. Chen: None. C. Kao: None. S. Lin: None. Y. Wang: None. Funding Chang Gung Memorial Hospital more...

Four mononuclear Cu(i)-halide complexes containing phosphines and pyridine ligands with strong electron donor substituents, [CuCl(PPh3)2(4-NMe2py)] (1), [CuI(PPh3)2(4-NH2py)] (2), [CuI(POP)(4-NH2py)] (3), and [CuI(POP)(4-NMe2py)]·0.5(Et2O) (4), (PPh3 = triphenylphosphine, 4-NMe2py = 4-(dimethylamino)pyridine, POP = bis[(2-diphenyl-phosphino)phenyl]ether, 4-NH2py = 4-aminopyridine, Et2O = diethyl ether) were synthesized and studied with regard to their structural, photophysical properties and theoretical calculations. The complexes exhibit pure blue thermally activated delayed fluorescence (λmax = 442 (1), 436 (2), 464 (3), and 448 nm (4)) in crystalline at room temperature. Emission lifetime analyses and density functional theory (DFT) calculations show that the blue-light emission at room temperature is the singlet (metal + halide)-to-ligand charge transfer state, (1(M + X)LCT), while that at 77 K is the state of 3(M + X)LCT transition character, owing to the small singlet-triplet energy gaps (ΔE = 660-1680 cm-1). X-ray diffraction structure analysis, photophysical studies and theoretical calculations suggest that the much larger torsion angle between the N-heterocyclic rings and N-Cu-X planes of complex 3 than that of 1, 2 and 4 might causes the bathochromic shift of luminescence, although these complexes containing similar heterocycle ligands. more...

Co–Ni layered double hydroxides (LDHs), as promising supercapacitor electrode materials with high specific capacity, have suffered from poor rate properties and cycling stability. Doping and topochemical oxidation of Ni ions is considered as an efficient route to overcome these drawbacks. In this work, Ni3+ doped cobalt–nickel layered double hydroxides (Co–Ni-LDHs) were synthesized by pulse laser ablation of a Ni target in CoCl2 aqueous solution. The existence of Ni3+ ions doped in Co–Ni-LDHs decreases the conductive resistance, and increases the mobility of surface charge and transfer rate of the electrolyte. As a result, the Ni3+ doped Co–Ni-LDHs display a maximum specific capacitance of 2275 F g−1 and 1450 F g−1 at the current density of 1 A g−1 and 20 A g−1, respectively, indicating a high rate of specific capacitance. Moreover, the capacitance retention is 80% after 1800 cycles at the current density of 6 A g−1, manifesting good cycling stability of Ni3+ doped Co–Ni-LDHs. more...

Based on a multi-dentate salicylhydrazide-derived ligand, a Zn-contained metal–organic gel that could stand for months has been prepared. The driving force within the supramolecular assembly was discussed by studying the gelation conditions, optical spectra, dynamic rheology and mass spectra. These studies revealed that both the coordination bonds and hydrogen bonds participate in the supramolecular assembly. In addition, electrostatic force also played as a key role in stabilizing the gel phase. The charge nature of the colloidal particle is negative charged. Consequently, the xerogel shows significant adsorption behavior that favors positively charged dye molecules, such as methyl violet and methylene blue. The title gel exhibits gelation-induced fluorescence enhancement property. When the gel was exposed to ammonia vapor, a gel–solution transition occurred, accompanied by a great weakening of fluorescence. The phase transition and fluorescence switching were found to be reversible for at least seven cycles. The mechanism involved was studied and discussed. more...

Recently, we demonstrated the feasibility of subcutaneous transplantation of MIN6 cells embedded in a scaffold with poly(ethylene glycol) methyl ether (mPEG)-poly(Ala) hydrogels. In this study, we further tracked these grafts using magnetic resonance (MR) and bioluminescence imaging. After being incubated overnight with chitosan-coated superparamagnetic iron oxide (CSPIO) nanoparticles and then mixed with mPEG-poly(Ala) hydrogels, MIN6 cells appeared as dark spots on MR scans. For in vivo experiments, we transfected MIN6 cells with luciferase and/or incubated them overnight with CSPIO overnight, 5 × 106 MIN6 cells embedded in mPEG-poly(Ala) hydrogels were transplanted into the subcutaneous space of each nude mouse. The graft of CSPIO-labeled MIN6 cells was visualized as a distinct hypointense area on MR images located at the implantation site before day 21. However, this area became hyperintense on MR scans for up to 64 days. In addition, positive bioluminescence images were also observed for up to 64 days after transplantation. The histology of removed grafts showed positive insulin and iron staining. These results indicate mPEG-poly(Ala) is a suitable scaffold for β-cell encapsulation and transplantation. Moreover, MR and bioluminescence imaging are useful noninvasive tools for detecting and monitoring mPEG-poly(Ala) hydrogel-embedded MIN6 cells at a subcutaneous site. more...

The liver is the current site of choice for clinical islet transplantation, but many intraportal grafts were lost in the early stage of transplantation. Other disadvantages include the difficulty of monitoring the islets and procedure-associated complications. In contrast, the subcutaneous space offers the advantages of a large space, a less invasive procedure and easy graft monitoring and removal. However, islet transplantation into an unmodified subcutaneous site has poor efficacy; possibly due to poor oxygenation and inadequate vascularization of the transplanted tissue. In this study, we tested the feasibility of subcutaneous transplantation of MIN6 beta cells embedded in temperature-sensitive poly(ethylene glycol) methyl ether (mPEG)-Ala hydrogels as scaffolds. After culturing for 14 days, the viability of MIN6 beta cells in mPEG-Ala hydrogel was comparable with those in medium, either assayed by MTT or LIVE/DEAD. Static incubation showed that both had comparable insulin secretion. For in vivo experiments, we infected MIN6 beta cells with luciferase by AAV and then transplanted 5*106 cells embedded in mPEG-Ala hydrogel into the subcutaneous space of each nude mouse’s upper back. Positive In Vivo Imaging System (IVIS) images and positive insulin staining of tissue histology were observed up to 41 days after transplantation. Meanwhile, we incubated MIN6 beta cells with chitosan-coated superparamagnetic iron oxide (CSPIO) overnight and then transplanted 5*106 MIN6 beta cells into the subcutaneous tissue of each nude mouse’s left flank. The graft of CSPIO-labeled MIN6 beta cells was visualized on Magnetic Resonance (MR) scans as distinct hypointense spots on T2-weighted images located at the transplantation site at day 6 and 20. These results indicate that subcutaneous transplantation of MIN6 beta cells embedded in temperature-sensitive mPEG-Ala hydrogels is feasible. Moreover, the IVIS and MR imaging are useful tools for detecting and monitoring beta cells at the subcutaneous site. Disclosure J. Juang: None.H. Lin: None.C. Chen: None.C. Kao: None.S. Wu: None.S. Lin: None.C. Shen: None.J. Wang: None.I. Chu: None. more...

The hot compressive experiments of 20CrMnTiH steel were performed on Gleeble-3500 thermo-simulation machine. The dynamic recrystallization mathematical models were developed based on experimental data. The effect laws of the deformation temperature on the microstructure evolution of 20CrMnTiH steel were investigated by coupling finite element method (FEM) with the developed dynamic recrystallization mathematical models. The results show that the dynamic recrystallization and the average grain sizes increased with the increasing deformation temperature and the higher deformation temperature is instrumental to dynamic recrystallization. The average grain size simulated using FE model agree well with the corresponding experimental results. more...

Circular dichroism is known to be the feature of a chiral agent which has inspired scientist to study the interesting phenomena of circularly polarized light (CPL) modulated molecular chirality. Although several organic molecules or assemblies have been found to be CPL-responsive, the influence of CPL on the assembly of chiral coordination compounds remains unknown. Herein, a chiral coordination polymer, which is constructed from achiral agents, was used to study the CPL-induced enantioselective synthesis. By irradiation with either left-handed or right-handed CPL during the reaction and crystallization, enantiomeric excesses of the crystalline product were obtained. Left-handed CPL resulted in crystals with a left-handed helical structure, and right-handed CPL led to crystals with a right-handed helical structure. It is exciting that the absolute asymmetric synthesis of a chiral coordination polymer could be enantioselective when using CPL, and provides a strategy for the control of the chirality of chiral coordination polymers. more...

Shape-anisotropic nanomaterials with uniform lengths and widths have attracted much interest but few of them are involved in self-assembled manganese complexes. The combination of two redox-active acylthiosemicarbazide ligands with Mn3+ cations leads to two discrete polynuclear Mn nanorods, pentanuclear [Mn5(L3)6][Mn0.7(DMF)1.4(H2O)2.8] (1a) and trinuclear Mn3(L4)3·2DMF (2), whose L3 and L4 represent N-(5-(2-hydroxyphenyl)-1,3,4-oxadiazol-2-yl)benzamide and N-(5-(2-hydroxyphenyl)-1,3,4-oxadiazol-2-yl)-propionamide, respectively, which are in situ synthesized from their acylthiosemicarbazide derivatives in the presence of Mn3+ cations, while the latter are reduced into divalent ones in rod-like moieties. For each pentanuclear anion in 1a, the charge is balanced by a solvated trivalent manganese cation, which can be replaced by two tetramethylammonium cations to yield pure valence compound 1b. Moreover, the magnetic studies reveal all of them possess antiferromagnetic properties. more...

Five heterometallic complexes were prepared in aqueous solution at 3–5 °C and characterized by elemental analyses, inductively coupled plasma analysis, IR spectra, UV–Vis spectra, powder X-ray diffraction and X-ray single-crystal diffraction. Complex 1–5 all contain 4d–4f super tetrahedron cluster anions, which are constructed by LnIII ions (Ln = NdIII, PrIII), [MoO4]2− and [Mo7O24]6− anions. Differences among 1–5 lie on the assembly of super tetrahedron anions by excess LnIII and TMII (TM = CoII, NiII, CuII or ZnII), which generates bigger cluster anions (complex 1–4) or anions with 1D infinite structure (complex 5). The assemble styles for synthons mentioned above show with capped style, head-to-head linking style or side-by-side linking style. more...

A new kind of trinuclear copper(II) motif [Cu3L] was prepared in situ by adopting a multidentate ligand, N′2,N′2′-bis(2-hydroxybenzoyl)biphenyl-2,2′-dicarbohydrazide (H6L), in the presence of a series N-containing agents. Featuring five different assembly styles, [Cu3L(DMF)2.5(hmta)]·3H2O (1), [Cu3L(DMA)(H2O)(Hmor)] (2), [Cu3L(py)2]·DMF (3), [Cu3L(DMF)(H2O)]·2DMF (4), and [Cu3L(DMA)(H2O)]·0.5DMA (5) (hmta = hexamethylenetetramine, Hmor = morphiline, py = pyridine) were obtained. In these assemblies, the [Cu3L] units are connected with each other into one-dimensional chains via bridging of N-containing agents or via sharing an oxygen atom of L6− to fuse together. Furthermore, the connecting styles are found to be governed by the character of the N-containing agents used, which is discussed in detail. Thermal gravimetric analysis and magnetic measurement of some complexes were performed. more...

Precision forging of the helical gear is a complex metal forming process under coupled effects with multi-factors. The high forming load is required to fill the teeth corner, which significantly causes failure, plastic deformation and wear of dies. The maximum forming load during precision forging helical gear is calculated by the finite element method (FEM). Combining the FEM simulation results with the artificial neural networks (ANN), backward propagation (BP) neural network is trained using the data of FEM simulation as learning sample. The trained BP neural network is validated using test samples and used to predict the maximum forming load under the different deformation conditions. The results show that the predicted results agree well with the simulated ones, the differences of prediction results exhibit low value, the predicted precision satisfy the request of industry. more...

A 3-fold interpenetrated uninodal 5-connected zfy network, based on a trigonal bipyramid Zn2(CO2)2(NN) unit, with excellent chemical and thermal stability has been synthesized, which shows triple aromatic walls and nanoscale one-dimensional square channels. more...

A series of Ln–Ni heterometallic coordination polymers, {[Ln2Ni(MIDA)4(H2O)6](H2O)4} (Ln = La (1), Ce (2), Pr (3), and Nd (4); H2MIDA = N-methyl-iminodiacetic acid), were obtained under hydrothermal conditions. Single crystal X-ray diffraction revealed that they feature two-dimensional isomorphic frameworks, which could be viewed as the construction by one-dimensional {Ln}n chain connecting by bridges of [Ni(MIDA)2]2. The magnetic measurements reveal that compounds 2–4 exhibit antiferromagnetic properties. TGA results indicate compounds 1 and 4 have good thermostability with the critical temperature of 375 °C. more...

Take a automobile bumper for example, analysis of effect of process parameters on warpage of a automobile bumper, including melt temperature, injection time, cooling time and packing pressure, on the warpage of the automobile bumper were analyzed by means of Moldflow software. The results show the warpage decrease of the increase of the injection time, the cooling time and the packing pressure, but when the packing pressure reached 45MPa, the warpage slightly increased; the melt temperature should be picked out by the characteristics of the plastics material. more...

Reactions of Pb(CH3COO)2·3H2O, MNO3 (M = K, Rb, and Cs) with m-H2BDC (1,3-H2BDC = 1,3-benzenedicarboxylic acid) in a mixed-solvent of DMF and methanol (v/v = 2/1) resulted in the formation of novel metal–organic frameworks [(Me)4N]2[Pb6M6(m-BDC)9(OH)2]·H2O (1: M = K; 2: M = Rb; 3: M = Cs). With H2SDBA (H2SDBA = 4,4′-sulfonyldibenzoic acid), two new lead(II) coordination polymers, [K2Pb(SDBA)2(μ3–H2O)]·3H2O (4) and [Cs2Pb2(SDBA)3(DMF)] DMF (5), were isolated. These complexes have been fully characterized by elemental analysis, PXRD, FTIR, TGA and single crystal X-ray diffraction. Compounds 1–3 are 3-D coordination frameworks built by a novel 12-metal heterometallic Pb6-M6 cage that extends topologically into an eight-connected hex network viaisophthalic acid ligands. Compounds 4 and 5 are new 3-D lead(II) MOFs constructed by ladder-like Pb(II)/K(I)/SDBA2− and rod-shaped Pb(II)/Cs(I)/SDBA2− motifs, respectively. The Pb(II) ions in these complexes show different coordination geometries with various coordination numbers (5, 7 and 9). In addition, an ideal T-shaped μ3-H2O is observed in 4. The SDBA2− ligands in 4 and 5 display three types of new coordination modes that have not been observed before. At room temperature, 1–3 exhibit strong emissions in the solid-state which can be attributed to ligand-to-metal charge transfer between the delocalized π bonds of carboxylate groups and p orbitals of lead(II) centers. more...

Polymer-stabilized iron oxide nanoparticles could be used as contrast agents in magnetic resonance imaging (MRI) due to their unique superparamagnetism. Here we demonstrate a quaternized chitosan, i.e. N-[(2-hydroxy-3-trimethylammonium)propyl] chitosan chloride (HTCC), encapsulating superparamagnetic iron oxide (SPIO), with very low toxicity and less effect on cell growth. HTCC has quaternary amino groups introduced into the chitosan chain, and such modification of chitosan should render it soluble in water. Most importantly, the HTCC―SPIO thus prepared has the ability to accelerate the MRI relaxation processes of surrounding water protons, resulting in enhanced MRI contrast (R2: y = 0.1076x ― 0.0092; R1: y = 0.008x ― 0.0005). The iron content quantified by Prussian blue staining and MRI revealed a positive correlation between Prussian blue positive cells and the change of MRI signal intensity. Also, transmission electron microscopy and element mapping confirmed intracellular metal-like spots as internalized iron oxide. Such findings support the use of these quaternized chitosan-stabilized iron oxide nanoparticles as a potential MRI contrast agent for cell tracking. more...

Superparamagnetic iron oxide nanocrystals (SPION) and their colloidal solutions of magnetic nanoparticles (ferrofluid) appear to contribute to the magnetite imaging applications. Here we present an aqueous ferrofluid in physiological pH and its cell tracking potential. In situ coating method was adapted to synthesize N-[(2-hydroxy-3-trimethylammonium) propyl] chitosan chloride (HTCC)-coated SPION. Characterization results reveal their features as follows: (1) z -average diameter of 274.1 ± 1.934 nm; (2) polydispersity index (PDI) of 0.135 ± 0.029; (3) zeta potential of 11.4 ± 0.410 mV; (4) iron concentration of 5.4 mg Fe/ml; (5) stable in both water and normal saline; (6) uptake by a variety of cell lines and (7) little cytotoxicity. Finally, islet grafting experiments demonstrated the potential usefulness of this product as a MRI contrast agent for cell tracking. more...

A series of new 3D coordination polymers Ln2(BTC)1.5(H2O)(DMSO) (Ln Eu(1), Gd(2), Tb(3), Dy(4), Ho(5)) (H4BTC = 1,2,4,5-benzenetetracarboxylic acid) have been solvothermal synthesized by the reactions of lanthanide ions with 1,2,4,5-benzenetetracarboxylic acid in a DMSO/H2O solution. These compounds possess the same 3D architectures based on dinuclear lanthanide SBUs {Tb2O4} linked by BTC4− anions and exhibit unprecedented 3D topological nets. Compounds 1 and 3 are strong luminescent materials which display characteristic Eu3+ and Tb3+ emission bands in the visible region. The magnetic properties of 2–5 have also been investigated through the measurement of their magnetic susceptibilities over the temperature range of 2–300 K. more...

Subperiosteal placement of nasal implants has been performed widely for dorsal nasal augmentation in Asia. The authors introduced anatomical and biomechanical studies to investigate the influence of the periosteum on the subperiosteal technique.Nasal periosteum on 20 cadavers was investigated by hematoxylin and eosin staining and biomechanical methods. Nasal profiles (n = 160) and motility testing (n = 1317) were used to analyze patients who underwent augmentation rhinoplasty between 2003 and 2008. An alternative high-split subperiosteal technique was developed for higher placement of the nasal implant.In the cadaver study, the authors discovered that the periosteum and bone were bound together by Sharpey's fibers below the nasion (1.3 +/- 0.6 mm) that penetrated into the nasofrontal suture. The nasal periosteum above the nasofrontal suture (1.77 +/- 0.19 mm) was thicker than the one below the suture (0.83 +/- 0.15 mm) (p0.001). Men had relatively thicker periosteum (1.41 +/- 0.49 mm) compared with women (1.18 +/- 0.5 mm), and the difference was statistically significant (p0.001). Motility testing for clinical cases revealed that there was a higher percentage of the mobilized implant in women than in men (p = 0.042). When the subperiosteal technique was compared with the subcutaneous technique, analysis of the Poisson ratio for the periosteum (0.33 +/- 0.02) indicated greater strength than in the subcutaneous tissue (0.45 +/- 0.02). The alternative high-split subperiosteal technique significantly shortened the radix-to-glabella distance, increased the radix height, and made the nasofrontal angle more obtuse than the conventional subperiosteal technique (p0.001, p0.001, and p = 0.02, respectively).Analysis of the nasal periosteum provided scientific support for using the subperiosteal technique in dorsal nasal augmentation. more...

Neprilysin has been singled out as the most promising candidate for use in the degradation of Abeta as a therapy for Alzheimer's disease. In this study, a quenched fluorogenic peptide substrate containing the first seven residues of the Abeta peptide plus a C-terminal Cysteine residue was synthesized to detect neprilysin activity. A fluorophore was attached to the C-terminal Cysteine and its fluorescence was quenched by a quencher linked to the N-terminus of the peptide. When this peptide substrate was degraded by an endopeptidase, fluorescence was produced and proved to be a sensitive detection system for endopeptidase activity. Our results showed that this assay system was extremely sensitive to neprilysin and insulin-degrading enzyme, but insensitive, or much less sensitive, to other Abeta-degrading enzymes. As low as 0.1 nM of neprilysin and 0.2 nM of insulin-degrading enzyme can be detected. more...

Breast asymmetries and scoliosis influence the results of augmentation mammaplasty. Although a variety of methods have been proposed to resolve breast asymmetries, to date, no simple preoperative algorithm has been proposed for predicting the breast volume and decreasing breast asymmetries in the place of subjective or expensive evaluation. The relationship between the scoliosis and breast volume asymmetry was further analyzed statistically in this study.The study enrolled 60 scoliotic patients from 780 patients undergoing augmentation mammaplasty between January 2000 and March 2008. The average follow-up period was 2 years. The inclusion criteria required hypoplastic breasts, a difference in bilateral breast volumes greater than 20 ml, and scoliosis with a Cobb angle greater than 10 degrees . The authors' surgical algorithm demonstrated an anthropomorphic equation for predicting breast volume and selecting the correct implant size.Pearson regression analysis showed that the breast volume asymmetry difference was significantly correlated with the severity of scoliosis (Cobb angle) (correlation coefficient, 0.901). No correlation between the difference in pre- and postoperative nipple and inframammary levels and the severity of scoliosis was noted. Augmentation mammaplasty significantly decreased the breast asymmetry differences (volume and nipple level) (p0.001). The average preoperative estimated breast volume was 45.3 ml for the smaller breast and 88.4 ml for the larger breast.This study found that the severity of scoliosis showed significant correlation with the breast volume asymmetry differences. Augmentation mammaplasty for breast asymmetries decreased not only the volume difference but also the difference in nipple levels. more...

Three new cluster-based Cu II -azide coordination polymers, [Cu 8 (N 3 ) 16 (222-tet) 2 ] n (1), [Cu 10 (N 3 ) 20 (dien) 2 ] n (2), and [Cu 12 (N 3 ) 24 (Me 5 dien) 2 ] n (3) as well as a 1D polymer [Cu 2 (N 3 ) 4 -(dien)] n (4) were prepared by hydrothermal reactions of Cu II ions with NaN 3 in the presence of various polyamines. Single-crystal X-ray diffraction studies reveal that 1 has a 1D chain structure based on an octanuclear cluster unit {Cu 8 (N 3 ) 16 -(222-tet) 2 }. Complexes 2 and 3 are 3D polymers and in both cases the azido anions display five different bridging modes (μ-1,1, μ-1,3, μ-1,1,1, μ-1,1,3,μ-1,1,1,3). Compound 4 is a 1D chain that represents the first example of a Cu II -azide compound that contains cis-EE, double EO, and terminally bonded azido ligands. The magnetic susceptibility data, measured from 2 to 300 K, showed ferromagnetic couplings in 1, 2, and 4 and antiferromagnetic interaction in 3. The magnetic data of 1 and 4 were fitted with rough models, giving the exchange coupling constants J = 4.19 cm -1 for 1 and J = 25.31 cm -1 for 4. more...

New tetracarboxylate ligands with dihydroxy (L(1)) and crown ether functionalities (L(2)) have been synthesized and treated with Cu(II) and Zn(II) ions to generate three-dimensional (3D) metal-organic frameworks (MOFs) with the compositions of [Cu(2)(L(1))(H(2)O)(2)].14DMF.10H(2)O, 5, [Cu(2)(L(2))(H(2)O)(2)].12DMF, 6, [Zn(6)(mu(4)-O)(L(1))(2)(L(1)-H(2))].35DMF.27H(2)O, 7, and [Zn(3)Na(2)(L(2))(2)(DMF)(2)].7DMF.14H(2)O, 8. The four compounds show different framework structures with different connectivities. Compound 5 exhibits the PtS topology whereas compound 6 has a [6(4).8(2)](3)[6(6)] topology. Compound 7 adopts a new [4.6(5)][4(2).6(8)][4(4).6(2)][4(5).6][4(8).6(10).8(3)] topology while compound 8 exhibits the Flu topology. The porosity and H(2) uptake were studied by gas sorption experiments and grand canonical Monte Carlo (GCMC) simulations. Compound 5 shows a high H(2) uptake of up to 1.11 wt % at 77 K. more...

通讯作者地址: Long, LS (通讯作者), Xiamen Univ, Coll Chem & Chem Engn, Dept Chem, State Key Lab Phys Chem Solid Surface, Xiamen 361005, Peoples R China 地址: 1. Xiamen Univ, Coll Chem & Chem Engn, Dept Chem, State Key Lab Phys Chem Solid Surface, Xiamen 361005, Peoples R China 电子邮件地址: lslong@xmu.edu.cn, zhiping@u.arizona.edu more...

Five Cu(II)/benzoate/4,4‘-bipy complexes, namely, [Cu(H2O)(benzoate)2(4,4‘-bipy)2](benzoic acid)2·(4,4‘-bipy) (1), [Cu2(H2O)2(benzoate)4(4,4‘-bipy)3]·(H2O)9 (2), [Cu2(benzoate)4(4,4‘-bipy)3] (3), [Cu3(H2O)4(benzoate)6(4,4‘-bipy)4.5]·(4,4‘-bipy)·(H2O)5 (4), and [Cu3(OH)2(H2O)2(benzoate)4(4,4‘-bipy)2] (5) (4,4‘-bipy = 4,4‘-bipyridine), have been synthesized through hydrothermal reaction of copper(II) nitrate, benzoic acid, and 4,4‘-bipyridine under different pH conditions. The diverse product structures show the marked sensitivity of the structural chemistry of the aromatic carboxylate ligand to synthesis conditions. Complex 1, which exhibits a zero-dimensional (0D) structure of mononuclear copper(II), is formed at pH = 5.5. At pH = 6.0, dimeric copper(II) complexes of 2 and 3 are formed. Reaction at pH = 7 leads to a one-dimensional (1D) structure of 4. A further increase of the pH to 8.0 results in a two-dimensional (2D) structure of 5. Crystal data are monoclinic, space group P2/n, a = 13.992(4) A, b = 5... more...

Solvothermal reactions of Cu(NO3)2·3H2O with trimesic acid (H3BTC) at different pH conditions yield two coordination polymers of [Cu3(BTC)2(H2O)3(NH3)4]n·2nH2O (1) and [Cu4(BTC)2(OH)2(H2O)2(NH3)4]n (2). Crystal structural analysis reveals that complex 1 exhibits a three-fold parallel interpenetration network and complex 2 shows a two-dimensional bilayer structure. Crystal data are orthorhombic, space group Pbcn, a = 11.242(3) A, b = 16.963(4) A, c = 13.898(4) A, Z = 4 for 1 and monoclinic, space group C2/c, a = 18.887(4) A, b = 10.761(2) A, c = 14.488(3) A, β = 126.100(3)°, Z = 4 for 2. more...

Nitric oxide (NO) is one of the most important interneural signaling molecules mediating hippocampal functions for learning and memory. The diurnal expression of neuronal NO synthase (nNOS) has been well studied. However, the temporal profile and underlying mechanisms of inducible NOS (iNOS) expression in a normal photoperiod or in altered light-dark cycles remain unclear. We examined the temporal profile of iNOS expression in adult male Sprague-Dawley rats maintained in a 12h-light/ 12h-dark photoperiod (12L/12D), which were pre-synchronized for 7 days before the experiment. The protein and mRNA levels of iNOS in the cortex and hippocampus were measured to examine the photic influences on iNOS expression. The results showed rhythmically changes of the levels of iNOS mRNA and protein in the hippocampus, but not in the cerebral cortex. The iNOS mRNA levels peaked at Zeitgeber time (ZT) 6 and ZT22, and the protein levels peaked at ZT8 and ZT18. Notably, the peaks in iNOS mRNA and protein levels in the 12L/12D group were 10 to 12 h apart, and the rhythmic pattern was absent in the 24-h period of the darkness group. In addition, the level of the phosphorylated cAMP response element binding protein (phospho-CREB) was the highest at ZT18, prior to a peak in iNOS mRNA expression at ZT22. A phospho-CREB-iNOS signaling pathway was further confirmed by the interaction of phospho-CREB and the iNOS DNA in histone complexes isolated by chromatin immunoprecipitation at ZT18. In conclusion, the photoperiod affects the diurnal expression of iNOS and activation of CREB in the hippocampus, which provide clues for the possible impact of circadian changes in hippocampal functions. more...

In the previous study (Tsai and Yen , 2003) we had described a simple method for the construction of microwire arrays consisting of evenly spaced insulated microwires in either horizontal or vertical orientations. In addition to the single row arrayed microwire electrode , two or more rows microwire arrays also used frequently (Ghazanfar et al., 2000 ; Shuler et al., 2001; Donoghue, 2002). In this letter, we describe a simple procedure to fabricate multi-row microwire arrays on the basis of the previous work (Tsai and Yen, 2003) but some key steps were improved. A two rows, separated by lmm , of 8 microwires array is described to illustrate the fabrication procedure . Each row of array consists of 8 Tefloninsulated microwires (AM system, Carlsborg,WA; #790700) which are aligned in single file , with an inter-electrode separation of 600700 u in for a total u horizontal span of 5 mm . The straightened microwires were cut into sixteen 3 -cm segments, and approximately 2 mm of insulation was removed from one end . Two slim bamboo sticks were fixed about 1-1.5 cm apart onto a piece of paper with sticky tape to serve as the fabrication jig. A razor blade was used to make notches in the bamboo sticks to mark the positions of the microwires . A small drop of epoxy glue was spread evenly on the surface of the sticks, and the straightened microwires were placed into these notches before the glue solidified . After all the microwires were placed in their proper positions, another drop of epoxy glue was applied to the sticks to cover the wires and fix a piece of PE-50 tube (od = 1 mm) on each stick as the spacer. When the epoxy glue had solidified , the free ends of the microwires were bent to the left . Another piece of microwire (about 10 mm) was glued to the arrayed wires transversely 2 mm from the distal stick. This transverse microwire will help to keep the arrayed more...