Isomerization-induced fluorescence enhancement of two new viologen derivatives: mechanism insight and DFT calculations.

The dark-colored viologen radical cations are unstable in air and easily fade, thus greatly limiting their applications. If a suitable substituent is introduced into the structure, it will have the dual function of chromism and luminescence, which will broaden its application field. Here, Vio1·2Cl and Vio2·2Br were synthesized by introducing aromatic acetophenone and naphthophenone substituents into the viologen structure.

Anthraquinone-1,8-Derived (Pseudo-) Crown and Lariat Ethers:Design and Applications as Fluorescent and Chromogenic Ion (Pair) Sensors.

Cyclic polyamine/ethers embedded with anthraquinone moieties and functional pendants, are structural analogues of crown ethers and (oxo-) cyclams, and could be utilized as sensitive and selective chemosensors towards metal cations. Those pseudo- (similar but geometrically distinct) crown and lariat ethers show various cation-binding patterns and stoichiometry, being modulated by donor type, cavity size and pendants' chelating ability. The luminescent and chromogenic properties also differ a lot along with the derivation of the parental macrocycle.

Structures and Chromogenic Ion-Pair Recognition of a Catechol-Functionalized 1,8-Anthraquinone Macrocycle in Dimethyl Sulfoxide.

A lariat anthraquinone macrocycle functionalized with catechol (HL) was synthesized via the Mannich reaction. The Mannich base HL can be partially decomposed into L1·3HO and HL1·NO·2HO in the presence of tetrabutylammonium hydroxide/Al(NO)·9HO in dimethyl sulfoxide (DMSO). Free L1·3HO is essentially coplanar, while protonated HL1·NO·2HO is highly distorted.

Fluorescent perylene derivative functionalized titanium oxide gel for sensitive and portable ascorbic acid detection.

An inorganic titanium oxide (TiO) gel sensor was demonstrated for convenient detection of ascorbic acid (AA). It is composed of TiO (PI-TiO) functionalized with a perylene diimide derivative containing carboxylic groups as a new soft dopant material. A traditional solvothermal reaction is adopted to prepare the PI-TiO composite, which exhibits a different spectrum according to the reaction time.

Bis(2-pyridylmethyl)amine-functionalized alizarin: an efficient and simple colorimetric sensor for fluoride and a fluorescence turn-on sensor for Al in an organic solution.

A complexone analog chemosensor, H2L, bearing chelating bis(2-pyridylmethyl) amine and alizarin groups was synthesized via the Mannich reaction. H2L chromically responds to OH-, F-, CH3COO-, and H2PO4- in DMF, CH3CN, and acetone, but not in CH3OH or H2O. The addition of F- ions to H2L selectively induces a significant and visible color change in acetonitrile and shifts both methylene proton signals upfield.

Induced pluripotent stem cells as a potential therapeutic source for corneal epithelial stem cells.

Corneal blindness caused by limbal stem cell deficiency (LSCD) is one of the most common debilitating eye disorders. Thus far, the most effective treatment for LSCD is corneal transplantation, which is often hindered by the shortage of donors. Pluripotent stem cell technology including embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) have opened new avenues for treating this disease.

An anionic sod-type terbium-MOF with extra-large cavities for effective anthocyanin extraction and methyl viologen detection.

An anionic sod-type zeolitic metal-organic framework [(CH3)2NH2]9{Tb6(η6-TATAT)4(H2O)12}·3Cl·DMA·7H2O [1, H6TATAT = 5,5',5''-(1,3,5-triazine-2,4,6-triyltriimino)tri-1,3-benzenedicarboxylic acid] has been synthesized by metal-ligand directed assembly of hexacarboxylic acid units and Tb3+ ions. Compound 1 with extra-large cavities can efficiently extract natural product anthocyanins from blackberries and release them rapidly into NaCl aqueous solution. And, the nature of the anionic framework makes it very sensitive to detect cationic methyl viologen (MV2+) with a detection limit as low as 1 × 10-8 M.

Reasons of Dysphagia After Operation of Anterior Cervical Decompression and Fusion.

Study Design: Retrospective study.

Objective: To analyze the reasons, clinical manifestation, risk factors, prevention, and treatment of dysphagia after operation of anterior cervical decompression and fusion (ACDF).

Summary Of Background Data: Dysphagia is one of severe complications after ACDF.

A Homochiral {Co Co } Supertetrahedral T Cluster from a Racemic Ligand with Ferromagnetic Behavior and High Photocatalytic Activity.

A homochiral mixed-valence cobalt cluster [Co Co (μ -O) (μ -OH) (S-bme) (OAc) ]Cl ⋅5 CH OH⋅18 H O (1, Hbme=1H-(benzimidazol-2-yl)ethanol) was synthesized from a racemic ligand and three cobalt salts of CoCl ⋅6 H O, Co(Ac) ⋅4 H O and Co(NO ) ⋅6 H O in a DMF/MeOH mixed solvent. The enantioselective coordination occurs when a large excess of cobalt ions added in the solution and only the S-configuration of the racemic ligand involved in crystallization. The CD spectra of three crystal samples show identical Cotton signals, indicating the repeatability and the enantiomeric purity of the single crystals.

Phenolacetyl Viologen as Multifunctional Chromic Material for Fast and Reversible Sensor of Solvents, Base, Temperature, Metal Ions, NH Vapor, and Grind in Solution and Solid State.

Electron-withdrawing/coordinating -phenolacetyl-substituted viologen can act as a visual sensor for solvents, bases, and temperature in organic solvents. Due to chelating phenolacetyl groups, this viologen can coordinate to Fe(III), Cu(II), and ZnCl in aqueous and DMF solutions. Interestingly, this viologen can respond to temperature, grind, and NH vapor in its solid state.

Clinicopathological features for predicting central and lateral lymph node metastasis in papillary thyroid microcarcinoma: Analysis of 66 cases that underwent central and lateral lymph node dissection.

Currently the surgical approach for papillary thyroid microcarcinoma (PTMC), particularly the range of lymph node dissection, remains controversial. The present study aims to evaluate the risk factors for central and lateral lymph node metastasis (CLNM and LLNM) for appropriate clinical decision of neck lymph node dissection in PTMC. A total of 66 cases of PTMC that underwent unilateral or bilateral lobectomy plus prophylactic cervical lymph node dissection were collected for clinicopathological evaluation, including age, gender, tumor size, subtypes, extrathyroidal invasion, multifocality, calcifications, loss of cellular polarity/cohesiveness (LOP/C) in the invasive front, CLNM and LLNM, and retrospectively analysis.

High Sensitivity Viologen for a Facile and Versatile Sensor of Base and Solvent Polarity in Solution and Solid State in Air Atmosphere.

Viologen cations are excellent electro- and photochromic materials. They generally have no response or very low sensitivity to bases. In this paper, three compounds, 1,1'-bis(2-oxo-2-phenylethyl)-4,4'-bipyridinium (viologen) with different substituents, including H (1), Cl (2), and OH (3), were synthesized.

A metal-organic framework constructed using a flexible tripodal ligand and tetranuclear copper cluster for sensing small molecules.

A new porous metal-organic framework (MOF) {[Cu4(OH)2(tci)2(bpy)2]·11H2O} (1) based on a tetranuclear copper cluster with intracluster antiferromagnetic interactions was synthesized. Quartz crystal microbalance (QCM) sensor studies reveal sensitive and selective sensing for small molecules.

Simultaneous Determination of Seven Components from Hawthorn Leaves Flavonoids in Rat Plasma by LC-MS/MS.

In this study, a simple, sensitive, and throughout liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for the simultaneous determination of seven flavonoid compounds, namely, rutin, vitexin-4″-O-glucoside, vitexin-2″-O-rhamnoside, hyperoside, vitexin, shanyenoside A and quercetin in rat plasma after intravenous administration of hawthorn leaves flavonoids (HLF) using lysionotin as an internal standard (IS). The target compounds were extracted using protein precipitation by methanol. The detection was achieved by LC-MS/MS in multiple reaction monitoring mode.

Two nanocage anionic metal-organic frameworks with rht topology and {[M(H2O)6]6}(12+) charge aggregation for rapid and selective adsorption of cationic dyes.

Two rht anionic metal-organic frameworks were synthesized. There are six [M(H2O)6](2+) ions held together by a super-strong H-bond and arranged in a regular octahedron in each medium cage. Dye adsorption studies revealed a rapid and selective adsorption of cationic dyes and the adsorbed dyes can be released in saturated NaCl aqueous solution.

Synthesis, spectroscopy, and binding constants of ketocatechol-containing iminodiacetic acid and its Fe(III), Cu(II), and Zn(II) complexes and reaction of Cu(II) complex with H₂O₂ in aqueous solution.

A new neuromelanin-like ketocatechol-containing iminodiacetic acid ligand, (N-(3,4-dihydroxyl)phenacylimino)diacetic acid (H4L), which is also quite similar to compounds found in insect cuticle, has been synthesized and characterized. The X-ray crystal structure of H4L has been successfully determined. Proton binding and coordination with Fe(III), Cu(II), and Zn(II) have been studied by potentiometric titrations and UV-vis spectrophotometry in aqueous solution.

Aspartic acid functionalized water-soluble perylene diimide as "Off-On" fluorescent sensor for selective detection Cu(2+) and ATP.

Aspartic functionalized water-soluble perylene diimide, N,N'-di(2-succinic acid)-perylene-3,4,9,10-tetracarboxylic diimide (PASP) has two absorbance maximums at 527 and 498nm (ε≈1.7×10(4)Lcm(-1)mol(-1)) and two emission peaks at 547 and 587nm respectively. Emission intensities decrease with the increase of PASP concentrations in 20-100μM ranges.

Dinuclear complexes of copper and zinc with m-xylene/cyclohexane-linked bis-aspartic acids: synthesis, characterization, dioxygen activation, and catalytic oxidation of nitrobenzene in pure aqueous solution.

Two new m-xylene/cyclohexane-linked bis-aspartic acid ligands, L(b) and L(c), were synthesized via Michael addition in basic aqueous solution. Their structures were characterized by elemental analysis, NMR and MS spectrometry. Both ligands react with Cu(II) and Zn(II) to form dinuclear complexes, with M2L(OH)(-) the major species in neutral/weak basic aqueous solution.

Synthesis, spectra, and electron-transfer reaction of aspartic acid-functionalized water-soluble perylene bisimide in aqueous solution.

An aspartic acid-functionalized water-soluble perylene bisimide, N,N'-di(2-succinic acid)-perylene-3,4,9,10-tetracarboxylic bisimide (PASP) was synthesized and characterized. It has absorbance maximum A(0-0) and A(0-1) at 527 and 498 nm (ε ≈ 1.7 × 10(4) L cm(-1) mol(-1)) respectively in pH 7.

Ligand field effect tuned magnetic behaviors of two chain compounds based on Mn(III)3O units: from slow magnetic relaxation to metamagnetism.

Two chain compounds built with anti-anti acetate bridged Mn(III)(3)O units, [Mn(3)O(Clppz)(3)(EtOH)(4)(OAc)](n) (1) and [Mn(3)O(Clppz)(3)(EtOH)(2)(OAc)](n) (2), were synthesized and characterized. The magnetic studies indicate that 1 is a single-chain magnet with two slow magnetization relaxation processes which has for the first time been found in this type of chain complex, while 2 shows a field-induced metamagnetic behavior. The quite different magnetic behaviors resulted from the different number of coordinated ethanol molecules on the Mn(III)(3)O unit, four ethanol molecules for 1, and two ethanol molecules for 2.

[Preliminary clinical results of endoscopic discectomy followed by interbody fusion using B-Twin expandable spinal spacer].

Objective: To investigate the effectiveness and significance of percutaneous endoscopic discectomy followed by interbody fusion using B-Twin expandable spinal spacer for degenerative lumbosacral disc

Methods: Between January 2007 and August 2008, 21 patients with degenerative lumbosacral disc disease were treated with endoscopic discectomy followed by interbody fusion using B-Twin expandable spinal spacer. Among them, there were 13 males and 8 females with an average age of 52 years (range, 28-79 years). And the disease duration ranged from 3 months to 40 years (median, 9 months).

Application of intraoperative computed tomography with or without navigation system in surgical correction of spinal deformity: a preliminary result of 59 consecutive human cases.

Study Design: A retrospective analysis of patients undergoing spinal deformity correction surgery by the assistance of intraoperative computed tomography (iCT) with or without navigation system.

Objective: To share our preliminary experience and analysis of the iCT navigation system applied to spinal deformity surgery.

Summary Of Background Data: The iCT navigation system has been shown to improve accuracy and safety in posterior instrumentation.

N,N'-Dicarb-oxy-N,N'-dicarboxyl-ato(m-phenyl-ene)dimethanaminium monohydrate.

In the title inner salt, C(16)H(20)N(2)O(8)·H(2)O, two of four carboxyl groups are deprotonated, while the two imine groups are protonated. The two imino-diacetate groups are located on the same side of the benzene ring plane. Extensive inter-molecular O-H⋯O and N-H⋯O hydrogen bonds occur in the crystal.

Clinical application of computer-designed polystyrene models in complex severe spinal deformities: a pilot study.

Surgical treatment of complex severe spinal deformity, involving a scoliosis Cobb angle of more than 90 degrees and kyphosis or vertebral and rib deformity, is challenging. Preoperative two-dimensional images resulting from plain film radiography, computed tomography (CT) and magnetic resonance imaging provide limited morphometric information. Although the three-dimensional (3D) reconstruction CT with special software can view the stereo and rotate the spinal image on the screen, it cannot show the full-scale spine and cannot directly be used on the operation table.

Coordination polymer based on Cu(II), Co(II) and 4,4'-bipyridine-2,6,2',6'-tetracarboxylate: synthesis, structure and adsorption properties.

4,4'-Bipyridine-2,6,2',6'-tetracarboxylic acid H4L.3H2O, () and its copper(II) and cobalt (II) coordination polymers [Cu2L(H2O)4]2n () and {[Co(H2O)6].[Co3L2(H2O)2].