High-Nuclear Co-Added Polyoxometalate-Based Chain: Electrocatalytic Oxygen Production.

A high-nuclear Co-added polyoxometalate (CoAP) was synthesized via a hydrothermal reaction: H14.5K9Na7.5-{[Co8(µ2-OH)(µ3-OH)2(H2O)2(Co(H2O)GeW6O26)(B-α-GeW9O34)2][BO(OH)2][Co12(µ2-OH)(µ3-OH)5(H2O)3(Co(H2O)GeW6O26)(GeW6O26)(B-α-GeW9O34)]}·46H2O (1). The polyoxoanion of 1 contains a large Co20 cluster gathered by lacunary GeW6O26 and GeW9O34 subunits. 1 represents a one-dimensional (1D) chain formed by adjacent polyoxoanions coupling through a CoO6 double bridge, showing the first example of a high-nuclear CoAP-based inorganic chain. 1 served as an efficient electrocatalyst in oxygen evolution reactions (OERs).

Porphyrin-Sensitizers and Anthracene-Annihilators Built in Isostructural Frameworks for Investigating Triplet-Triplet Annihilation Upconversion.

In this study, four isostructural pillar-layered frameworks were constructed using a porphyrin layer and an anthracene pillar, which served as the sensitizer and annihilator, respectively, in the triplet-triplet annihilation upconversion (TTA-UC) system. Framework 1 demonstrated the highest upconversion quantum yield of 1.01%. Additionally, 1 and 2 also exhibited down-conversion fluorescence resulting from the porphyrin component. A twist intramolecular charge transfer (TICT) state was observed in the bianthracene chromophore of 2, resulting in transient rotation of two anthracene rings and red-shifted emission. Both computational studies and experiments confirmed the transition from a locally excited state to a TICT state upon the inclusion of polar guest molecules into the framework.

Polypyridyl Ru(II) or cyclometalated Ir(III) functionalized architectures for photocatalysis.

The chemistry of polypyridyl Ru(II) and cyclometalated Ir(III) derivatives provides long-lasting interest to researchers due to the inherent advantage of their triplet states in a variety of photoactivities. The introduction of Ru(N^N)3 and Ir(C^N)2(X^N) modules into well-defined architectures extends the research areas of both photoactive metal complexes and network chemistry, generating a lot of new opportunities with interesting structural aesthetics and profound functional possibilities. The rapid development of research in integrating Ru(II) or Ir(III) metallotecons into the architectures has been apparent in recent years which makes this a fascinating subject for reviewing. This review focuses on the design and syntheses of Ru(N^N)3 and Ir(C^N)2(X^N) functionalized architectures of metal-organic frameworks (MOFs), covalent-organic frameworks (COFs), metallasupramolecules, organic supramolecules and supramolecular organic frameworks (SOFs). Furthermore, the photocatalytic applications including the hydrogen evolution reaction (HER), carbon dioxide reduction reaction (CO2RR), photocatalytic oxidation and photoredox catalysis of organic transformation are also presented.

Lanthanide-Anderson Polyoxometalates Frameworks: Efficient Sulfide Photooxidation.

Three polyoxometalate-based metal-organic frameworks were synthesized by the thermal reaction of pyridyl-Anderson polyoxometalate linker and lanthanide ions. With the help of [Ru(bpy)3]2+ photosensitizer, these frameworks exhibited excellent photocatalytic sulfide oxidation performance with sulfoxide selectivity. The reactive oxygen species as well as the photooxidation mechanism were also explored.

Primary intraspinal benign tumors treated surgically: an analysis from China.

PURPOSE: The purpose of this study was to review the clinical features in a cohort of Chinese patients with primary intraspinal benign tumors. METHODS: This retrospective study included a consecutive series of patients with intraspinal benign lesions who received surgery between January 2014 and October 2018 at our hospital. We collected each patient's clinical data, including age, gender, presenting symptoms, the spinal level (cervical, thoracic, lumbar, or sacral), and location (intramedullary or extramedullary) of the tumor. RESULTS: A total of 66 patients were included in this study, of whom 24 were men and 42 (63.6%) were women. The mean age was 52.5 years (range, 21-76 years). The most common symptom was sensory deficits. The most common tumor type, found in 56.1% patients, was schwannoma, followed by meningioma in 33.3% patients. The commonly performed surgery included decompression of spinal canal and excision of spinal lesions. CONCLUSION: Primary intraspinal benign tumors occur in elderly and female population and at the thoracic region. Schwannoma and meningioma are the two with higher incidence. The surgical outcome in terms of tumor excision and functional recovery is good.

Suite of Organoplatinum(II) Triangular Metallaprism: Aggregation-Induced Emission and Coordination Sequence Induced Emission Tuning.

A series of triangular metallaprisms with a kinetically inert Pt-N bond have been synthesized from the stepwise assembly of a Pt-corner, linear linker 4,4'-bipy (4,4'-bipy = 4,4'-bipyridine) and triangular ligand [tpb or tpt, tpb = tris(4-pyridyl)benzene, tpt = tris(4-pyridyl)triazine]. The use of an unsymmetrical [Pt(HL)]-corner (H2L = 2,6-diphenylpyridine) leads to novel isostructural products. Phenyl rotation at the metal-corners endows these complexes with good aggregation-induced emission (AIE) function, with varied activities across the isostructural complexes. The coordination sequence of electron-deficient ligand tpt also imparts significant influence on the complex emission. These organoplatinum triangular metallaprisms thus provide a good model to study the influence of building blocks and coordination sequence on the luminescence of supramolecules.

Iridium-mediated regioselective B-H/C-H activation of carborane cage: a facile synthetic route to metallacycles with a carborane backbone.

One-pot reactions of carborane carboxylic acids (L), [Cp*IrCl2]2, and silver salt are reported, which lead to regioselective B-H or C-H bond activation at ambient temperature in good yields. This process is demonstrated for three carborane (o-, m-, p-) dicarboxylates, and metal-mediated B-H functionalization of a p-carborane derivative is accomplished for the first time. Two metal-induced self-assembly routes to tetra-nuclear metallacycles 3 and 5 were performed through B(4, 7)/H and B(2, 10)/H activation, respectively, and the two metallacycles were found to be stable and to exist in solution as discrete complexes. Different activation modes in the carborane cage were ascribed to the characteristic structure of the products and the electronic density differences. The analogous reaction of o-carborane monocarboxylate with the same metal precursor gave the C-H activation complex 6, indicating that the B-H bond is more stable than the C-H bond in this carborane cage. The selective activation was confirmed by DFT calculation results. In this study, a facile and efficient synthetic route has been developed through specific B-H bond activation to construct carborane-based metallacycles that are unavailable by conventional methods.

Neuroprotective effects of ginsenoside Rg1 on oxygen-glucose deprivation reperfusion in PC12 cells.

The present study was aimed to investigate the protective effects of ginsenoside Rg1 (GRg1), an important component of ginseng, in oxygen-glucose deprivation/reperfusion (OGDR) and to elucidate the related mechanisms. PC12 cells were used as the model of OGDR. GRg1 administration was started 12 h before OGD and lasted for 12 h. After OGD, the cells were incubated in drug-free and full culture medium under normoxic condition for 24 h. Cell viability was then measured using MTT assay. Cell morphology was studied under a microscope. The expressions of survivin, caspase-3 and Terminal dUTP nick-end labeling (TUNEL) were measured by immunocytology. Results showed that pretreatment with GRg1 significantly increased the viability and survivin expression, and decreased the expressions of caspase-3 and TUNEL in a dose-dependent manner. In addition, it dramatically increased the number of cells and improved the cellular morphology. These results demonstrate the effect of GRg1 in preventing OGDR-induced PC12 cell apoptosis and partly reveal the mechanisms of the protective effect. It is suggested that GRg1 has potential beneficial effects in ischemic diseases.

Self-assembly of molecular Borromean rings from bimetallic coordination rectangles.

In contrast to conventional stepwise synthesis of molecular Borromean rings, a self-assembly synthetic method which proceeds without the aid of a template has been developed. In the formation of molecular rectangles, by adjustment of the long-arm length of the rectangles, a series of size-dependent Borromean-link frameworks were constructed. Both the shortest length of two arms and the relative proportion of the length of the long arm to that of the short arm play a key role in the formation of Borromean rings. DFT calculations were used to provide theoretical support for the formation of discrete interlocked frameworks.

Cp*Rh-based heterometallic metallarectangles: size-dependent Borromean link structures and catalytic acyl transfer.

A series of Cp*Rh-based functional metallarectangles have been synthesized from metallaligands. Enlargement of one linker leads to the isolation of two novel Borromean link architectures. All these complexes are intact in solution, as evident from ESI-MS spectroscopic analysis. Arising from the combination of open Cu centers and favorable cavity space, {(Cp*Rh)4(bpe)2[Cu(opba)·2MeOH]2}4(OTf)·6MeOH shows extraordinary catalytic abilities with high efficiency and wide substrate selectivity in the acyl-transfer reaction.

A novel primary culture method for rat choroidal epithelial cells.

OBJECTIVE: To establish a method for the culture of primary choroidal epithelial cells. METHODS: This descriptive experimental study was carried out in Xi`an Jiaotong University, Xi`an, China from September 2009 to August 2012. Choroidal epithelial cells were isolated from the choroid plexus tissues of the lateral ventricles from neonatal rats (n=36). The tissues were dissociated into small cell aggregates by a mechanical method, and cultured on plastic culture dishes containing Dulbecco`s modified Eagle`s medium with 10% fetal bovine serum and 10 ng/ml epidermal growth factor at 37 degrees C in an incubator with 5% humidified carbon dioxide. The cultured cells were examined by phase contrast microscope, electron microscopy, and immunocytochemistry. RESULTS: The cells showed typical morphologic characteristics of epithelial phenotypes with a cobblestone appearance in monolayer 7-9 days post-seeding. The electron microscopy spotted typical choroidal epithelial cells with microvilli on the cytomembrane, organelles in the cytoplasm, and tight junctions welding 2 adjacent cells. They were positive against anti-transthyretin immunostaining. CONCLUSION: This culture technique, which does not require complex equipment and operation skills, might be a simple and efficient method for obtaining choroidal epithelial cells in sufficient number and purity from mixed primary cultures of rat tissue.

Anderson-type polyoxometalates for catalytic applications.

Anderson-type polyoxometalates have exhibited remarkable catalytic capabilities in a wide range of reactions. This discourse delves into the distinct categories of Anderson POMs and their respective catalytic reactions, which are examined in separate segments. These encompass the straightforward {XMo6} POMs, the organic grafting {XMo6} POMs, and the integration of POMs into POM cluster organic frameworks. It is important to highlight that specific catalytic functionalities can solely be accomplished via the utilization of Anderson-type POMs, thus emphasizing their indispensable role in future explorations.

Recent Progress of Covalent Organic Frameworks Applied in Electrochemical Sensors.

As an emerging porous crystalline organic material, the covalent organic frameworks (COFs) are given more and more attention in many fields, such as gas storage and separation, catalysis, energy storage and conversion, luminescent devices, drug delivery, pollutant adsorption and removal, analysis and detection due to their special advantages of high crystallinity, flexible designability, controllable porosities and topologies, intrinsic chemical and thermal stability. In recent years, the COFs are applied in analytical chemistry, for instance, chromatography, solid-phase microextraction, luminescent and colorimetric sensing, surface-enhanced Raman scattering and electroanalytical chemistry. The COFs decorated electrodes show high performance for detecting trace substances with remarkable selectivity and sensitivity, such as heavy metal ions, glucose, hydrogen peroxide, drugs, antibiotics, explosives, phenolic compounds, pesticides, disease metabolites and so on. This review mainly summarized the application of COF based electrochemical sensor according to different target analytes.

Ru(N

Covalent organic frameworks (COFs) have emerged as significant candidates for visible-light photocatalysis due to their ability to regulate performance which is achieved through the careful selection of building modules, framework conjugation, and post-modification. This report focused on the efficient transformation of an imine-linked I-COF into a π-conjugated quinoline-based Q-COF, which enhanced both the chemical stability and conjugation of the network. By methylating the pyridyl groups in the Q-COF, an N+-COF was obtained. Subsequently, the Ru(N^N)3-photosensitizer ([Ru(dcbpy)3]4-) was incorporated into the channels of the cationic N+-COF through electrostatic interactions, resulting in the formation of [Ru(dcbpy)3]4-⊂N+-COF. This composite exhibited exceptional photocatalytic activity, demonstrating high yields and selectivity in the oxidation of sulfides or amines to their respective products.

Reconstruction of comminuted long-bone fracture using CF/CPC scaffolds manufactured by rapid prototyping.

BACKGROUND: Stabilization and bone healing of fractures in weight-bearing long bones are challenging. This study was conducted to evaluate the effect of a scaffold composed of chitosan fiber and calcium phosphate ceramics (CF/CPC scaffold) on stability and fracture repair in weight-bearing long bones. MATERIAL/METHODS: Comminuted fractures of paired radiuses were created in 36 healthy, mature dogs. The left radius of each dog was classified in the experimental group and treated with CF/CPC scaffold, and the right one was not filled, and was used as a blank control. Of the 12 animals in each group that were killed at week 4, 8, and 12 after the operation, 6 were used for histological analysis, and the other 6 used were for biomechanical studies. Both radiuses from each animal were dissected free and stored for these analyses. All the animals underwent X-ray radiograph pre- and post-operatively. Computer-aided rapid-prototyping technologies were adopted for the fabrication of three-dimensional scaffolds with precise geometric control. RESULTS: X-ray showed that the bone fracture area in the experimental group was filled with callus at week 12 after surgery. Histological examination detected slow resorption of the cement and new bone formation since week 4. At week 12, the scaffold material partially degraded and was still present in all specimens. Mechanical testing revealed that the failure strength of the radiuses treated with CF/CPC scaffolds was about 3 times that of the radiuses without implanted scaffolds. CONCLUSIONS: The effect of using CF/CPC scaffold in treating comminuted weight-bearing long bone fractures is satisfactory.

Dual-AIEgens in one organoplatinum(II) metallaprism: photoluminescence exploration.

Two sets of cis-trans isostructural metallaprisms were constructed from the controlling linkage of a Pt-corner, and a linear and quadrilateral AIE ligand. The combination of two AIEgens of TPE and the Pt-corner into one system endows these isomers with interesting AIE functions.

Timing of Splenectomy after Acute Spinal Cord Injury.

Spinal cord injury (SCI) is a devastating condition. Splenectomy may play a protective role in the development of SCI. However, little is known about whether the timing of splenectomy affects the outcome after SCI. Investigation into splenectomy after SCI would provide insight into how the timing can be selected following SCI to improve neurologic outcomes. Rats were randomized into a sham group, a nonsplenectomized group (NonSPX), four splenectomized groups with the surgery performed immediately, 6 h, 12 h, and 24 h after SCI (SPX0, SPX6, SPX12, and SPX24, respectively). Rats were subjected to severe contusive SCI at the level of the third thoracic vertebra. At different time points following SCI, Basso, Beattie, and Bresnahan (BBB) score was used to assess the recovery of injury. The animals in each group were randomly selected for tissue collection at days 3, 14, and 28 after surgery. Then, immunohistochemistry of immunologic cells was performed and inflammatory mediators were determined. Our study showed that splenectomy within 6 h after SCI improved BBB scores as compared with splenectomy more than 12 h after SCI, and decrease the immune cell responses to SCI. Protein levels of interleukin (IL)-1ß and tumor necrosis factor (TNF)-α were significantly elevated in nonsplenectomized group compared with sham group. No difference was observed in IL-10 at the lesion site between splenectomized and nonsplenectomized groups at 3 d post-SCI. The study demonstrates that splenectomy within 6 h after SCI would lessen the development of SCI and improve outcome.

Change of neural stem cells in the choroid plexuses of developing rat.

Neural stem cells reside in various brain regions. However, neural stem cells in the choroid plexuses are poorly understood. This study was conducted to corroborate the hypotheses that there are neural stem cells in the choroid plexuses, and the change of neural stem cells is age dependent. We examined neural stem cells from rats at postnatal 1, 3, 7 days, 2, 4, 6, and 8 weeks to investigate the distribution and change of the cells in the choroid plexuses. We found nestin-positive cells in the choroid plexuses and these nestin-expressing cells were located principally at the boundary between the choroid plexus epithelium and the underlying connective tissue stroma. Some choroid plexuses of the postnatal 1-, 3-, 7-day, and 2-week rats were stained with line-like markers of nestin. We also observed nestin-positive cells in 4-week rats, but no such cells were detected in the 6- and 8-week rats. These findings indicate that neural stem cells exist in the rat choroid plexuses, and the change of neural stem cells is age-dependent.

Selective Photocatalytic Oxidation of Sulfides in Lanthanide Metal -Organic Frameworks Incorporating Ru(2,2'-bpy)3 photosensitizer.

Three isostructural lanthanide metal-organic frameworks (Ln-MOFs) were synthesized with uncoordinated N^N site, and the Ru(N^N)3 photosensitizer was introduced via coordination link. These functionalized frameworks showed excellent performance in the photocatalytic oxidation of sulfides with good conversion and high sulfoxide selectivity.

Bis(ß-diketone)-based metallacycles with haloalkane-induced fluorescence enhancement.

A series of metallarectangles 1-5 were synthesized by the selective combination of (p-cymene)Ru-corner, bis(ß-diketone) arms and bifunctional pyridyl linkers. They exhibited a very rare phenomenon of haloalkane-induced fluorescence enhancement.