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.

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.

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.

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.

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.

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.

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.

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.

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.

Three ring-shaped Zr(iv)-substituted silicotungstates: syntheses, structures and their properties.

Three Zr(iv)-substituted polyoxometalate nanoclusters, H16(H2dap)4[{Zr2(OH)2(α-SiW10O38)}2{Zr2(OH)2(ß-SiW10O38)}2]·8H2O (1, dap = 1,3-diaminopropane), H17Na9[(Zr2(OH)2)2(Zr2BO(OH)4)2(ß-SiW10O38)4]·50H2O (2) and H20Na8[(Zr2BO(OH)4)2(Zr2B2O2(OH)5)2(ß-SiW10O38)4]·40H2O (3), were made by a hydrothermal reaction of trivacant [A-α-SiW9O34]10-, Zr4+ ions, and H3BO3 under different alkaline conditions. Single-crystal X-ray structure analysis revealed that they are ring-shaped polyoxotungstate aggregates built by Zr2(OH)2 ({Zr2}) clusters and two types of dilacunary α-/ß-SiW10O38 ({α-/ß-SiW10}) fragments for 1, {Zr2}, {ß-SiW10}, and Zr2BO(OH)4 ({Zr2B}) clusters for 2, and {ß-SiW10}, {Zr2B}, and Zr2B2O2(OH)5 ({Zr2B2}) clusters for 3, respectively, showing that the Zr-B-O clusters, {Zr2B} and {Zr2B2}, have been introduced to the lacunary sites of polyoxometalates for the first time. The electrochemistry and electrocatalytic properties of 2 were studied, and it exhibited effective catalytic activities for the reduction of H2O2, NO2-, and BrO3-. Moreover, the catalysis of 2 for the oxidation reactions of various thioethers was investigated, and it was found that 2 possessed high conversion and remarkable selectivity.

Correlation between elevated inflammatory cytokines of spleen and spleen index in acute spinal cord injury.

BACKGROUND: Spinal cord injury (SCI) is a devastating disorder. After SCI, it initiates a robust immune response. Considering the spleen is one of the most important immune organs, the present study further characterizes the inflammatory cytokine profile of spleen in acute SCI. METHODS: Adult rats were divided into sham and SCI groups (n = 36). SCI was produced at the T3 vertebral level. The whole blood and spleen was collected at 6, 24, 48, 72, 120, and 168 h after SCI. The levels of the inflammatory factors (IL-1ß, IL-6, IL-10, TNF-α, and TGF-ß) in spleen and serum were measured with an ELISA kit. RESULTS: The results showed significantly elevated levels of IL-1ß, IL-6, IL-10 and TNF-α in spleen compared with control group levels. Inflammatory cytokine levels of spleen correlated negatively with spleen index. CONCLUSION: It was found that inflammatory cytokines in spleen showed dynamic responses to SCI, which suggest their specificity change of spleen caused by SCI. These results suggest that a possible involvement of spleen in the initiation of the inflammatory response after SCI.

Effects of ginsenoside Rb1 on spinal cord ischemia-reperfusion injury in rats.

BACKGROUND: The aim of this study was to evaluate the effects of different doses of ginsenoside Rb1 (GRb1) pretreatment on spinal cord ischemia-reperfusion (SCII) in rats and explore the potential mechanisms about the expression of survivin protein after the intervention. METHODS: A total of 90 healthy adult Sprague-Dawley (SD) rats were randomly divided into six groups: sham-operated (n = 15), SCII model (n = 15), and GRb1-treated groups (n = 60). The GRb1-treated group was divided into four subgroups: 10 mg/kg, 20 mg/kg, 40 mg/kg, and 80 mg/kg (n = 15). The corresponding dose of GRb1 was injected intraperitoneally 30 min before operation and every day after operation. Forty-eight hours after model establishment, the neurological function of hind limbs was measured with Basso, Beattie, and Bresnahan (BBB) scale. The superoxide dismutase (SOD) and malondialdehyde (MDA) levels in serum and spinal cord tissue were detected respectively. The expression of survivin protein was observed by immunofluorescence staining. HE and TUNEL staining were used to observe neural cell injury and apoptosis, respectively, in the spinal cord of rats with SCII. RESULTS: The intervention of different doses of GRb1 could increase SOD activity and decrease MDA content in serum and spinal cord tissue, increase survivin protein expression, and decrease neuronal apoptosis. It was dose-dependent, but there was no significant change between 40 mg/kg and 80 mg/kg. CONCLUSIONS: GRb1 could reduce the cell apoptosis induced by SCII through inhibiting oxidative stress. It can also inhibit apoptosis by promoting the expression of Survivin protein. Ginsenoside Rb1 had a dose-dependent protective effect on SCII in the dose range of 10 mg/kg-40 mg/kg.

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.

Cellular Inflammatory Response of the Spleen After Acute Spinal Cord Injury in Rat.

Spinal cord injury (SCI) involves both primary and secondary damages. After the phase of primary injury, a series of inflammatory responses initiate, which belong to the secondary injury. There has been little investigation into the cellular inflammatory response of the spleen to SCI. To disclose the impact of SCI on the spleen, we examined the inflammatory reactions of the spleen during the acute phase of SCI in rat. Adult rats were used as experimental animals and divided into un-injured, sham, and SCI groups (n = 36). Contusion injuries were produced at the T3 vertebral level. Spinal cords were harvested 6 h, 24 h, 48 h, 72 h, 120 h, and 168 h after surgery and were prepared for immunohistochemistry. Spleen wet weight was measured. Blood and spleens were prepared for quantitative analyses. The spleen index was significantly decreased in the SCI groups. Immunohistochemical results showed an increase of the infiltrating cells in the spinal cord tissues from SCI rats at all time points, peaking in 72 h post injury. In the blood, T and B lymphocytes significantly decreased in the SCI group as compared with the sham group, while monocyte increased. Surprisingly, in the SCI group, neutrophil initially decreased and subsequently tended to return toward baseline levels, then remained elevated until the end of the study. Spleen analyses revealed a significant increase in monocyte and neutrophil but a minor (not statistically significant) reduction in T and B lymphocytes. Our data show that the four most prevalent inflammatory cells infiltrate the spinal cord after injury. Increased levels of inflammatory cells (monocyte and neutrophil) in the blood and spleen appear to be very sensitive to SCI. The spleen plays a critical role in the acute phase of SCI.

Effects of passage and cryopreservation on neurotrophic factor secretion from choroid plexus epithelial cells.

The aim of the present study was to evaluate the effects of passage and cryopreservation of choroid plexus epithelial cells on their secretion of neurotrophic factors. Choroid plexus epithelial cells were cryopreserved and thawed following primary culture or passage cultured for up to two passages. The supernatant of primary, first/second passage and cryopreserved-thawed choroid plexus epithelial cells was collected when cells reached 80-90% confluence. ELISA was used to quantify brain-derived neurotrophic factor (BDNF), glial cell-derived neurotrophic factor (GDNF), nerve growth factor (NGF) and ciliary neurotrophic factor (CNTF) levels in the cell supernatant. First passage and cryopreserved-thawed cells secreted less BDNF and CNTF compared with primary cultured cells and increased levels of these two factors compared with second passage cells, and increased levels of GDNF and NGF compared with primary cultured and second passage cells (all P<0.05). Therefore, first passage culture decreased BDNF and CNTF secretion but increased NGF and GDNF compared with primary culture; second passage culture diminished neurotrophic factor secretion compared with first passage culture; and cryopreservation did not weaken the function of choroid plexus epithelial cells in secreting BDNF, GDNF, NGF and CNTF. The current study demonstrates that first passage and cryopreserved-thawed choroid plexus epithelial cells have an enhanced function to secrete neurotrophic factors including BDNF, GDNF, NGF and CNTF.

Self-assembled [2]catenane in trapezoidal metallacycles with [Cp*Ir]-corners.

A series of trapezoidal metallacycles were synthesized by the selective combination of a rigid with a flexible arm. [2]Catenane 3 was obtained by self-assembly when the cavity size of the trapezoidal rings was optimised.