Fabrication of Carboxylate-Functionalized 2D MOF Nanosheet with Caged Cavity for Efficient and Selective Extraction of Uranium from Aqueous Solution.

The efficient removal of radioactive uranium from aqueous solution is of great significance for the safe and sustainable development of nuclear power. An ultrathin 2D metal-organic framework (MOF) nanosheet with cavity structures was elaborately fabricated based on a calix[4]arene ligand. Incorporating the permanent cavity structures on MOF nanosheet can fully utilize its structural characteristics of largely exposed surface area and accessible adsorption sites in pollutant removal, achieving ultrafast adsorption kinetics, and the functionalized cavity structure would endow the MOF nanosheets with the ability to achieve preconcentration and extraction of uranium from aqueous solution, affording ultrahigh removal efficiency even in ultra-low concentrations. Thus, more than 97% uranium can be removed from the concentration range of 50-500 µg L-1 within 5 min. Moreover, the 2D nano-material exhibits ultra-high anti-interference ability, which can efficiently remove uranium from groundwater and seawater. The adsorption mechanism was investigated by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FT-IR) analysis, and density functional theory (DFT) calculations, which revealed that the cavity structure plays an important role in uranium capture. This study not only realizes highly efficient uranium removal from aqueous solution but also opens the door to achieving ultrathin MOF nanosheets with cavity structures, which will greatly expand the applications of MOF nanosheets.

Synthesis of Calix[4]arene-Based Porous Organic Cages and Their Gas Adsorption.

Two crystalline large-sized porous organic cages (POCs) based on conical calix[4]arene (C4A) were designed and synthesized. The four-jaw C4A unit tends to follow the face-directed self-assembly law with the planar triangular building blocks such as tris(4-aminophenyl)amine (TAPA) or 1,3,5-tris(4-aminophenyl)benzene (TAPB) to generate a predictable cage with a stoichiometry of [6+8]. The formation of the large cages is confirmed through their relative molecular mass measured using MALDI-TOF/TOF spectra. The protonated molecular ion peaks of C4A-TAPA and C4A-TAPB were observed at m/z 5109.0 (calculated for C336H240O24N32: m/z 5109.7) and m/z 5594.2 (calculated for C384H264O24N24: m/z 5598.4). C4A-POCs exhibit I-type N2 adsorption-desorption isotherms with the BET surface areas of 1444.9 m2 ⋅ g-1 and 1014.6 m2 ⋅ g-1. The CO2 uptakes at 273 K are 62.1 cm3 ⋅ g-1 and 52.4 cm3 ⋅ g-1 at a pressure of 100 KPa. The saturated iodine vapor static uptakes at 348 K are 3.9 g ⋅ g-1 and 3.5 g ⋅ g-1. The adsorption capacity of C4A-TAPA for SO2 reaches to 124.4 cm3 ⋅ g-1 at 298 K and 1.3 bar. Additionally, the adsorption capacities of C4A-TAPA for C2H2, C2H4, and C2H6 were evaluated.

CREB-binding protein and HIF-1α/ß-catenin to upregulate miR-322 and alleviate myocardial ischemia-reperfusion injury.

Myocardial ischemia/reperfusion injury (MIRI) is a prevalent condition associated with numerous critical clinical conditions. miR-322 has been implicated in MIRI through poorly understood mechanisms. Our preliminary analysis indicated potential interaction of CREB-binding protein (CBP), a transcriptional coactivator and acetyltransferase, with HIF-1α/ß-catenin, which might regulate miR-322 expression. We, therefore, hypothesized that CBP/HIF-1α/ß-catenin/miR-322 axis might play a role in MIRI. Rat cardiomyocytes subjected to oxygen-glucose deprivation /reperfusion (OGD/R) and Langendorff perfused heart model were used to model MIRI in vitro and in vivo, respectively. We used various techniques such as CCK-8 assay, transferase dUTP nick end labeling staining, western blotting, RT-qPCR, chromatin immunoprecipitation (ChIP), dual-luciferase assay, co-immunoprecipitation (Co-IP), hematoxylin and eosin staining, and TTC staining to assess cell viability, apoptosis, and the levels of CBP, HIF-1α, ß-catenin, miR-322, and acetylation. Our results indicate that OGD/R in cardiomyocytes decreased CBP/HIF-1α/ß-catenin/miR-322 expression, increased cell apoptosis and cytokines, and reduced cell viability. However, overexpression of CBP or miR-322 suppressed OGD/R-induced cell injury, while knockdown of HIF-1α/ß-catenin further exacerbated the damage. HIF-1α/ß-catenin bound to miR-322 promoter to promote its expression, while CBP acetylated HIF-1α/ß-catenin for stabilization. Overexpression of CBP attenuated MIRI in rats by acetylating HIF-1α/ß-catenin to stabilize their expression, resulting in stronger binding of HIF-1α/ß-catenin with the miR-322 promoter and subsequent increased miR-322 levels. Therefore, activating CBP/HIF-1α/ß-catenin/miR-322 signaling may be a potential approach to treat MIRI.

Calix[4]arene-Derived 2D Covalent Organic Framework with an Electron Donor-Acceptor Structure: A Visible-Light-Driven Photocatalyst.

The calixarenes are ideal building blocks for constructing photocatalytic covalent organic frameworks (COFs), owing to their electron-rich and bowl-shaped π cavities that endow them with electron-donating and adsorption properties. However, the synthesis and structural confirmation of COFs based on calixarenes are still challenging due to their structural flexibility and conformational diversity. In this study, a calix[4]arene-derived 2D COF is synthesized using 5,11,17,23-tetrakis(p-formyl)-25,26,27,28-tetrahydroxycalix[4]arene (CHO-C4A) as the electron donor and 4,7-bis(4-aminophenyl)-2,1,3-benzothiadiazole (BTD) as the acceptor. The powder X-ray diffraction data and theoretical simulation of crystal structure indicate that COF-C4A-BTD exhibits high crystallinity and features a non-interpenetrating undulating 2D layered structure with AA-stacking. The density functional theory theoretical calculation, transient-state photocurrent tests, and electrochemical impedance spectroscopy confirm the intramolecular charge transfer behavior of COF-C4A-BTD with a donor-acceptor structure, leading to its superior visible-light-driven photocatalytic activity. COF-C4A-BTD exhibits a narrow band gap of 1.99 eV and a conduction band energy of -0.37 V versus normal hydrogen electrode. The appropriate energy band structure can facilitate the participation of ·O2- and h+ . COF-C4A-BTD demonstrates high efficacy in removing organic pollutants, such as bisphenol A, rhodamine B, and methylene blue, with removal rates of 66%, 85%, and 99% respectively.

Loss of YAP1 C-terminus expression as an ancillary marker for metaplastic thymoma: a potential pitfall in detecting YAP1::MAML2 gene rearrangement.

AIMS: Metaplastic thymoma is a rare thymic tumour characterized by Yes Associated Protein 1 (YAP1) and Mastermind Like Transcriptional Coactivator 2 (MAML2) gene fusions resulting from an intrachromosomal inversion of chromosome 11. Immunohistochemistry with an antibody directed against the C-terminus of YAP1 has shown loss of expression in YAP1-rearranged vascular neoplasms, poromas, and porocarcinomas. This study aimed to validate an anti-YAP1 C-terminal antibody as an ancillary immunohistochemical marker for the diagnosis of metaplastic thymoma. MATERIALS AND METHODS: Ten metaplastic thymomas were selected for the current study. Fluorescence in situ hybridization (FISH), next-generation sequencing (NGS), and reverse transcription-polymerase chain reaction (RT-PCR) analyses were performed to detect YAP1::MAML2 fusions. We then performed immunohistochemistry to detect YAP1 C-terminus expression in 10 metaplastic thymomas, 50 conventional thymomas (10 each of type A thymoma, type AB thymoma, type B1 thymoma, type B2 thymoma, and type B3 thymoma) and seven thymic carcinomas. RESULTS: All 10 cases showed narrow split signals with a distance of nearly two signal diameters and sometimes had false-negative results in YAP1 and MAML2 break-apart FISH (BA-FISH). Abnormal colocalized signals of the YAP1::MAML2 fusion were observed in all 10 cases using fusion FISH (F-FISH) assays. Eight of 10 cases with adequate nucleic acids were successfully sequenced and all showed YAP1::MAML2 fusions; in two cases the fusions were detected by both DNA and RNA sequencing and in six cases by RNA sequencing only. YAP1::MAML2 fusion transcripts were identified in four cases by RT-PCR. Metaplastic thymoma showed loss of YAP1 C-terminus expression in all 10 (100%) cases. All other thymic neoplasms showed retained YAP1 C-terminus expression. CONCLUSION: YAP1 C-terminus immunohistochemistry is a highly sensitive and specific ancillary marker that distinguishes metaplastic thymoma from its mimics. BA-FISH assays could not effectively detect YAP1::MAML2 fusions due to the proximity of the two genes. Loss of YAP1 C-terminus expression is a reliable surrogate for the detection of YAP1::MAML2 fusions in metaplastic thymoma.

Reversible Single-Crystal-to-Single-Crystal Transformation of a Coordination Polymer through Solar-Switchable Cycloaddition and Cycloreversion Reaction.

Reversible covalent reactions within crystalline complexes are powerful tools for the design and developing of new generation of reusable smart materials. In this work, a unique photoreactive olefin-containing metal-organic coordination polymer [Ag2(2,3-ppe)2(1,3-bdc)]n (1) was prepared by the hydrothermal reaction between AgNO3, 1-(2-pyridyl)-2-(3-pyridyl)ethylene (2,3-ppe), and 1,3-benzenedicarboxylic acid (1,3-H2bdc). When exposed to sunlight, 1 can undergo single-crystal-to-single-crystal (SCSC) transformation to form [Ag2(dpdpcb)(1,3-bdc)]n (1a, dpdpcb = 1,3-di(2-pyridyl)-2,4-di(3-pyridyl)cyclobutane) through a [2 + 2] cycloaddition reaction. 1a can regenerate into 1 via the cycloreversion reaction based on the thermal effect of sunlight. Such a metal-organic complex exhibits interesting fluorescence switching behavior during the unprecedented fully solar-controlled reversible SCSC reaction, which makes it possible to be applied to the fields of optical memory storage and anti-counterfeiting.

Luminescent Two-Dimensional Metal-Organic Framework Nanosheets with Large π-Conjugated System: Design, Synthesis, and Detection of Anti-Inflammatory Drugs and Pesticides.

Two-dimensional (2D) metal-organic framework (MOF) nanosheets, with largely exposed surface area and highly accessible active sites, have emerged as a novel kind of sensing material. Here, a luminescent 2D MOF nanosheet was designed and synthesized by a facile top-down strategy based on a three-dimensional (3D) layered MOF {[Zn(H2L)(H2O)2]·H2O}n (Zn-MOF; H4L = 3,5-bis(3',5'-dicarboxyphenyl)-1H-1,2,4-triazole). With a large π-conjugated system and rigid planar structure, ligand H4L was elaborately selected to construct the bulk Zn-MOF, which can be readily exfoliated into 2D nanosheets, owing to the weak interlayer interactions and easy-to-release H2O molecules in the interspaces of 2D layers. Given the great threat posed to the ecological environment by anti-inflammatory drugs and pesticides, the developed luminescent Zn-MOF nanosheets were utilized to determine these organic pollutants, achieving highly selective and sensitive detection of diclofenac sodium (DCF) and tetramethylthiuram disulfide (TMTD). Compared to the detection limits of 3D Zn-MOF (7.72 ppm for DCF, 6.01 ppm for TMTD), the obviously lower detection limits for 2D Zn-MOF nanosheets toward DCF (0.20 ppm) and TMTD (0.18 ppm) further revealed that the largely exposed surface area with rigid planar structure and ultralarge π-conjugated system greatly accelerated electron transfer, which brought about a vast improvement in response sensitivity. The remarkable quenching performance for DCF and TMTD stems from a combined effect of photoinduced electron transfer and competitive energy absorption. The possible sensing mechanism was systematically investigated by the studies of powder X-ray diffraction, UV-vis, luminescence lifetime, and density functional theory calculations.

Fabrication of Protonated Two-Dimensional Metal-Organic Framework Nanosheets for Highly Efficient Iodine Capture from Water.

Radioactive iodine (129I and 131I), produced or released from nuclear-related activities, posed severe effects on both human health and environment. The efficient removal of radioiodine from aqueous medium and vapor phase is of paramount importance for the sustainable development of nuclear energy. Herein, a metal-organic framework (MOF) nanosheet with a positive charge was constructed for the capture of iodine for the first time. The as-synthesized ultrathin nanosheets, with a thickness of 4.4 ± 0.1 nm, showed a record-high iodine adsorption capacity (3704.08 mg g-1) from aqueous solution, which is even higher than that from the vapor phase (3510.05 mg g-1). It can be ascribed to the fully interactions between the extensive accessible active sites on the largely exposed surface of 2D MOF nanosheets and the target pollutants, which also gave rise to fast adsorption kinetics with relative high removal efficiencies in the low concentrations, even in seawater. Moreover, a facile recyclability with fast desorption kinetics can also be achieved for the MOF nanosheets. The excellent iodine removal performance in aqueous solution demonstrated that the electrostatic attraction between MOF nanosheets with a positive charge and the negatively charged triiodide (I3-, the dominant form of iodine in aqueous solution) is the driving force in adsorption, which endows the adsorbents with the characteristics of fast adsorption and desorption kinetics. The adsorption mechanism was systematically verified by the studies of ζ potential, Fourier transform infrared, X-ray photoelectron spectroscopy, and Raman spectra.

Crystallographic Visualization of a Guest-Induced Solar-Driven Cycloaddition Reaction Based on a Recyclable Nonporous Coordination Polymer.

Stimuli-responsive solids with adjustable photophysical properties are particularly attractive because they can be used as smart materials in anticounterfeiting, information storage, holographic imaging, and other fields. Herein, we report a unique nonporous coordination polymer, {[Ag(3,3'-dpe)](2,2'-Hbpdc)}n (1; 3,3'-dpe = 1,2-dipyridin-3-ylethene and 2,2'-H2bpdc = 2,2'-biphenyldicarboxylic acid), that can convert to an extremely photoreactive compound, 1·H2O·MeCN (MeCN = acetonitrile), through guest capture. Upon irradiation of sunlight, 1·H2O·MeCN can transform to {[Ag(3,3'-tpcb)0.5](2,2'-Hbpdc)(H2O)(MeCN)}n (2·H2O·MeCN; 3,3'-tpcb = 1,2,3,4-tetrapyridin-3-ylcyclobutane). 2·H2O·MeCN can lose its solvent molecules to form 2 and further return to 1 at high temperature. Accompanied by direct visualization based on multistep single-crystal-to-single-crystal conversions, the recyclable crystalline solid exhibits remarkable fluorescence changes, which makes it a supramolecular switch for application in multiple anticounterfeiting.

[Characteristic spectrum and decoction process of classical prescription Qingwei San].

In this experiment, by determination of the HPLC characteristic spectrum of the classical prescription Qingwei San decoction, the contents of isoferulic acid, palmatine and paeonol in Qingwei San decoction and the extraction rate were investigated. The factors such as the crushing degree of decoction pieces, the amount of decocting water, the decocting time, the filter material and the decocting container involved in Qingwei San decoction process were examined to make a detailed comparison of Qingwei San's decoction processes during the development.HPLC characteristic spectrum method of Qingwei San was established, and then the decoction process parameters of Qingwei San were optimized, with the similarity of characteristic spectrum, the concentration of the index components and the extraction rate as indexes. The decoction process of Qingwei San was determined as follows: Qingwei San decoction pieces were weighed according to the prescription amount and pulverized into the most coarse powder; the powder was put in a ceramic pot, added with 225 mL water, heated to boiling, cooked for 50 minutes with gentle heat(100 W), and filtered with a layer of 300 mesh nylon cloth.The similarity of Qingwei San's characteristics pectrum of different decoction methods was all above 0.9, and the concentration of isoferulic acid, palmatine and paeonol in Qingwei San under determined decoction process was 40.74, 26.73, 65.73 µg·mL~(-1), respectively, with an extraction rate of 33.80%.The characteristic spectrum determined in this experiment can better express the information and index components of Qingwei San, and if combined with the extraction rate information, it can provide the general information, index component content and extraction information. The decoction process after detailed investigation can better reflect the quality of Qingwei San decoction, with easier control and operation. It can provide a basis for the subsequent research and development of Qingwei San decoction standard, and can also provide experimental basis and reference for the decoction process research of other classical prescriptions.

Expression of GluA2-containing calcium-impermeable AMPA receptors on dopaminergic amacrine cells in the mouse retina.

Purpose: The neuromodulator dopamine plays an important role in light adaptation for the visual system. Light can stimulate dopamine release from dopaminergic amacrine cells (DACs) by activating three classes of photosensitive retinal cells: rods, cones, and melanopsin-expressing intrinsically photosensitive retinal ganglion cells (ipRGCs). However, the synaptic mechanisms by which these photoreceptors excite DACs remain poorly understood. Our previous work demonstrated that α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate (AMPA) receptors contribute to light regulation of DAC activity. AMPA receptors are classified into Ca2+-permeable and Ca2+-impermeable subtypes. We sought to identify which subtype of AMPA receptors is involved in light regulation of DAC activity. Methods: AMPA receptor-mediated light responses and miniature excitatory postsynaptic currents were recorded from genetically labeled DACs in mouse retinas with the whole-cell voltage-clamp mode. Immunostaining with antibodies against tyrosine hydroxylase, GluA2 (GluR2), and PSD-95 was performed in vertical retinal slices. Results: The biophysical and pharmacological data showed that only Ca2+-impermeable AMPA receptors contribute to DAC light responses driven by ipRGCs or cones (via depolarizing bipolar cells). We further found that the same subtype of AMPA receptors mediates miniature excitatory postsynaptic currents of DACs. These findings are supported by the immunohistochemical results demonstrating that DACs express the PSD-95 with GluA2, a subunit that is essential for determining the impermeability of AMPA receptors to calcium. Conclusions: The results indicated that GluA2-containing Ca2+-impermeable AMPA receptors contribute to signal transmission from photosensitive retinal cells to DACs.

[Analysis on quality value transmitting of substance benchmarks of Linggui Zhugan Decoction].

By preparing 10 batches of the material reference of Linggui Zhugan Decoction,the methodology of the characteristic spectrum of the material reference was created. The creaming rate range,the contents and the transfer rate range of cinnamaldehyde,glycyrrhizin and glycyrrhizic acid,the characteristic peaks and the similarity range of the characteristic spectrum of Linggui Zhugan Decoction were determined to clarify key quality attributes of the material reference of Linggui Zhugan Decoction. In the 10 batches of the material reference of Linggui Zhugan Decoction,the similarity of characteristic spectrum was higher than 0. 9. Furthermore,after summarizing the characteristic peak information,we knew that Fuling had two characteristic peaks,Guizhi had six characteristic peaks,Baizhu had two characteristic peaks and Gancao had 11 characteristic peaks. The average creaming rate of the material reference of the ten batches was( 12. 13 ± 0. 35) %. The average content of cinnamaldehyde was 0. 32%,the average transfer rate was 10. 69%,the content of cinnamaldehyde in the different batches was between 0. 22% and 0. 42%,and the transfer rate was between 7. 48% and13. 90%. The average content of glycyrrhizin was 0. 84%,the average transfer rate was 50. 39%,the content of glycyrrhizin in the different batches was between 0. 42% and 1. 26%,and the transfer rate was between 35. 27% and 65. 51%. The average content of glycyrrhizic was 1. 88%,the average transfer rate was 40. 74%,the content of glycyrrhizic in the different batches was between 0. 94% and2. 82%,and the transfer rate was between 28. 52% and 52. 96%. In this paper,the quality value transmitting of substance benchmarks of Linggui Zhugan Decoction was analyzed by the combination of characteristic spectrum,creaming rate and the content of index component. A scientific and stable method was preliminarily established,which provided scientific basis for the quality control and formulation development of Linggui Zhugan Decoction.

M1 ipRGCs Influence Visual Function through Retrograde Signaling in the Retina.

UNLABELLED: Melanopsin-expressing intrinsically photosensitive retinal ganglion cells (ipRGCs, with five subtypes named M1-M5) are a unique subclass of RGCs with axons that project directly to many brain nuclei involved in non-image-forming functions such as circadian photoentrainment and the pupillary light reflex. Recent evidence suggests that melanopsin-based signals also influence image-forming visual function, including light adaptation, but the mechanisms involved are unclear. Intriguingly, a small population of M1 ipRGCs have intraretinal axon collaterals that project toward the outer retina. Using genetic mouse models, we provide three lines of evidence showing that these axon collaterals make connections with upstream dopaminergic amacrine cells (DACs): (1) ipRGC signaling to DACs is blocked by tetrodotoxin both in vitro and in vivo, indicating that ipRGC-to-DAC transmission requires voltage-gated Na(+) channels; (2) this transmission is partly dependent on N-type Ca(2+) channels, which are possibly expressed in the axon collateral terminals of ipRGCs; and (3) fluorescence microscopy reveals that ipRGC axon collaterals make putative presynaptic contact with DACs. We further demonstrate that elimination of M1 ipRGCs attenuates light adaptation, as evidenced by an impaired electroretinogram b-wave from cones, whereas a dopamine receptor agonist can potentiate the cone-driven b-wave of retinas lacking M1 ipRGCs. Together, the results strongly suggest that ipRGCs transmit luminance signals retrogradely to the outer retina through the dopaminergic system and in turn influence retinal light adaptation. SIGNIFICANCE STATEMENT: Melanopsin-expressing intrinsically photosensitive retinal ganglion cells (ipRGCs) comprise a third class of retinal photoreceptors that are known to mediate physiological responses such as circadian photoentrainment. However, investigation into whether and how ipRGCs contribute to vision has just begun. Here, we provide convergent anatomical and physiological evidence that axon collaterals of ipRGCs constitute a centrifugal pathway to DACs, conveying melanopsin-based signals from the innermost retina to the outer retina. We further demonstrate that retrograde signals likely influence visual processing because elimination of axon collateral-bearing ipRGCs impairs light adaptation by limiting dopamine-dependent facilitation of the cone pathway. Our findings strongly support the hypothesis that retrograde melanopsin-based signaling influences visual function locally within the retina, a notion that refutes the dogma that RGCs only provide physiological signals to the brain.

Sesquiterpenoids with Various Carbocyclic Skeletons from the Flowers of Chrysanthemum indicum.

A phytochemical investigation of the flowers of Chrysanthemum indicum yielded sesquiterpenoids 1-25 with various carbocyclic skeletons, including 10 new (1-10) and 15 known (11-25) analogues. The structures were elucidated via their physical data, while the absolute configuration of compounds 6, 8, and 10 was assessed via electronic circular dichroism analysis. The evaluation of the effect of sesquiterpenoids on porcine epidemic diarrhea virus (PEDV) replication showed that compounds 1-5, 12, 14, 16, 17, 19, and 21 increased cell viability against cell death in PEDV-injected cells. Compounds 2, 12, and 17 were selected and investigated for their inhibition of proteins required for PEDV replication. Compounds 2 and 17 significantly reduced PEDV nucleocapsid and spike protein synthesis compared with azauridin as a positive control.

One-step hyperentanglement purification and hyperdistillation with linear optics.

We investigate a new approach for achieving hyperdistillation and hyperentanglement purification operations simultaneously on two-photon systems, whose state is described by nonlocal hyperentangled Bell states on both the spatial mode and polarization degree of freedoms. Exploiting linear optics and local entanglement resource, the quantum nondemolition (QND) parity-checking measurement and the heralded two-qubit amplification could are key steps in our scheme. With the QND parity-checking measurement and heralded qubit amplification operations, both the bit-flip (phase-flip) errors caused by decoherence in noisy channels and the vacuum errors caused by the transmission losses can be corrected. We show that the proposed scheme provides a new solution to overcome the problem of photon losses and decoherence simultaneously, which could be achieved with current technologies.

Poly[aqua[µ(4)-3,3'-(diazenediyl)dibenzoato]zinc].

The solvothermal reaction of Zn(OAc)(2)·2H(2)O with 3,3'-(diazenediyl)dibenzoic acid (H(2)ADB) in H(2)O at 393 K afforded the title complex, [Zn(C(14)H(8)N(2)O(4))(H(2)O)](n). The asymmetric unit contains half a Zn(II) cation, half an ADB ligand and half a water molecule. Each Zn(II) centre lies on a crystallographic twofold rotation axis and is five-coordinated by four O atoms of bridging carboxylate groups from four ADB ligands and one O atom from a water molecule, forming a distorted trigonal-bipyramidal coordination geometry. The [Zn(H(2)O)] subunits are bridged by carboxylate groups to give one-dimensional [Zn(µ-COO)(4)(H(2)O)](n) chains. The chains are linked by ADB ligands into two-dimensional sheets, and these sheets are further connected to neighbouring sheets via hydrogen bonds (OW-HW...O), forming a three-dimensional hydrogen-bond-stabilized structure with an unprecedented 3(7)4(17)5(2)6(2) topology.

First and second instar larvae and adults of a new Homidia species (Collembola, Entomobryidae) recorded from Xizang Autonomous Region with three new records.

Three new recorded species of genus Homidia were collected from Xizang Autonomous Region, China, in the present paper. Among them, a new species, Homidiabreviseta Pan, sp. nov., is included in the present paper. This new species can be identified by having a single uninterrupted dark band on central thoracic segment III; 14 macrochaetae on abdominal segment I and seven on the posterior central abdominal segment IV (half segment); and very short bothriotricha on abdominal segments II-IV. It can be easily discriminated from similar species of Homidia by its colour pattern, chaetotaxy of the labium, and abdominal segments I and IV. The chaetotaxy of the first and second instar larvae of this new species and a key to four species of genus Homidia from Xizang are also provided.

Topological structural transformation of a two-dimensional coordination polymer via single-crystal to single-crystal photoreaction.

Photoreactive coordination polymers are particularly important media for the implementation of highly-selective photoreactions and creation of photoresponsive intelligent materials and devices. Herein, a two-dimensional (2D) photoreactive coordination polymer, formulated as [Cd(pha)(3,3'-bpe)]n (1) was prepared through the hydrothermal reaction between Cd(NO3)2·4H2O, phthalic acid (H2pha) and 1,2-bis(3-pyridyl)ethylene (3,3'-bpe). Upon exposure to 365 nm UV light, the 1H NMR spectroscopy and single crystal X-ray diffraction analysis results indicated that 1 can undergo a [2 + 2] photocycloaddition reaction and thus form a new coordination polymer [Cd(pha)(3,3'-tpcb)0.5]n (1a) through single-crystal to single-crystal (SCSC) transformation. Accompanied by the SCSC photoreaction, the 2D sql net of 1 converted into a 2D binodal network of 1a with the rare (324·627)(326272) topology. The SCSC transformation from 1 to 1a also exhibits an interesting photocontrolled fluorescence. The unique photoinduced structural change and fluorescence quenching of 1 makes it a potential intelligent material for optical anti-counterfeiting, fluorescence sensors and other fields.

Efficient and selective removal of Pb2+ from aqueous solution by using an O- functionalized metal-organic framework.

Lead (Pb) is one of the most widespread and highly toxic heavy metals in the environment. The design and synthesis of adsorbent materials for the selective and efficient removal of Pb2+ from aqueous solution has received much attention. Herein, the ligand 4,4'-azoxydibenzoic acid with the O- group was elaborately selected to construct a novel Pr-based MOF for Pb2+ removal. The as-prepared MOF adsorbents with high stability exhibited ultra-high selectivity for Pb2+, even in the presence of various highly concentrated competitive ions (with the ratios from 1 : 5 to 1 : 50). Also, a high uptake capacity (560.26 mg g-1) can be achieved for the MOF material, due to the availability of sufficient adsorption sites. The strong electrostatic attraction and coordination interaction between the numerous active O- sites on MOF adsorbents and Pb2+ can account for the good adsorption performance for Pb2+, which was systematically verified by zeta potential, FT-IR and XPS studies.

Differential analysis of intestinal microbiota and metabolites in mice with dextran sulfate sodium-induced colitis.

BACKGROUND: Intestinal micro-ecological imbalances impair the intestinal barrier and induce intestinal inflammation, for example, ulcerative colitis (UC). According to the latest research, abnormalities in intestinal microbiota structure and their metabolites play a dominant role in UC progression; in addition, they could affect the mucus barrier based on different factors. Although numerous studies have confirmed the important role of intestinal microbiota in UC pathogenesis, the intricate connection between microbiota and metabolites and mucus barrier in UC occurrence remains unclear, and correlation analyses of differential microbiota and their metabolites under UC are relatively scarce. AIM: To reveal the differential intestinal microbiota and metabolites in UC pathogenesis and explore more sensitive biomarker compositions. METHODS: We used the antibiotic combination method to establish intestinal pseudo-aseptic mice; afterward, dextran sulfate sodium (DSS) was applied to establish an acute experimental colitis mice model. Colitis severity, assessed based on disease activity index, colorectal length, colorectal wet weight, and histological lesions, and mucus-related staining (mucopolysaccharide alcian blue and immunofluorescence of mucin), was compared between the pseudo-aseptic and bacterial colitis mice. Finally, differential intestinal microbiota, metabolites, and their association and correlations, were analyzed by 16s rDNA sequencing in combination with non-targeted metabolomics, through gas chromatography-mass spectrometry. RESULTS: Compared with the pseudo-aseptic mice, intestinal bacteria positive mice were more severely ill and their intestinal mucus loss was more pronounced in DSS-induced colitis (P < 0.05), suggesting that different microbiota and metabolites could cause the different degrees of colitis. Subsequently, we observed that in addition to Klebsiella, and Bacteroides, which were widely associated with colitis, Candidatus Stoquefichus, Anaerobiospirillum, Muribaculum, and Negativibacillus may be involved in protection against colitis. Furthermore, differential metabolites of the microbiota were mainly enriched in the synthesis-related pathways of key structural sequences of mucin. In combination with the mucin-related staining and immunofluorescence results, the findings indicate that the differential microbiota and their metabolites potentially regulate the composition and function of mucus under colitis. CONCLUSION: Microbiota and their metabolites are major factors regulating the composition and function of mucus, in turn influencing the function and structure of intestinal mucus barrier under colitis. The different microbiota and metabolites identified in the present study could be novel biomarkers for colitis.