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A pair of enantiomeric tetrahedral cages have been constructed using a hexapod ligand. By utilizing large aromatic triphenylene as the core, the crystal structure of the metallo-cages exhibited a hierarchical packing due to the π–π interaction.

Here we have achieved accurate ligand tailoring at specific sites on calixarene-protected Cu(ii)-based metallamacrocycles.

To explore its potential causative role in CRC development, we evaluated the colon pathology, mucosa barrier, colon microbiota and host transcriptome profile afterThree groups of mice were compared to reveal the differences,Both the AOM/DSS and AOM/DSS-FUSO groups exhibited a significantly reduced body weight and increased tumor numbers than the control group, and AOM/DSS mice withOur study demonstrated that

PDF file - 2492K, Effect of 25D3 in combination with TBBz on CYP24A1 mRNA expression and cell proliferation in PC3 cell.

PDF file - 2596K, CYP24A1 mRNA expression in PC3 cell treated with TBBz and 1,25D3

PDF file - 56K, Prostate tumor and matching normal

Vitamin D has broad range of physiological functions and antitumor effects. 24-Hydroxylase, encoded by the CYP24A1 gene, is the key enzyme for degrading many forms of vitamin D including the most active form, 1,25D3. Inhibition of CYP24A1 enhances 1,25D3 antitumor activity. To isolate regulators of CYP24A1 expression in prostate cancer cells, we established a stable prostate cancer cell line PC3 with CYP24A1 promoter driving luciferase expression to screen a small molecular library for compounds that inhibit CYP24A1 promoter activity. From this screening, we identified, 4,5,6,7-tetrabromobenzimidazole (TBBz), a protein kinase CK2 selective inhibitor as a disruptor of CYP24A1 promoter activity. We show that TBBz inhibits CYP24A1 promoter activity induced by 1,25D3 in prostate cancer cells. In addition, TBBz downregulates endogenous CYP24A1 mRNA level in TBBz-treated PC3 cells. Furthermore, siRNA-mediated CK2 knockdown reduces 1,25D3-induced CYP24A1 mRNA expression in PC3 cells. These results suggest that CK2 contributes to 1,25D3-mediated target gene expression. Finally, inhibition of CK2 by TBBz or CK2 siRNA significantly enhances 1,25D3-mediated antiproliferative effect in vitro and in vivo in a xenograft model. In summary, our findings reveal that protein kinase CK2 is involved in the regulation of CYP24A1 expression by 1,25D3 and CK2 inhibitor enhances 1,25D3-mediated antitumor effect. Cancer Res; 73(7); 2289–97. ©2013 AACR.

Here, we systematically studied the self-assembly behavior of chiral polyoxytitanium clusters for the first time. Through the cooperative assembly of ferrocenecarboxylic acid and ketoxime ligands, we successfully incorporated the planar chirality of ferrocene (Fc) into the layered {Ti

The first Ti(iv)-based metallocalixarene nanocage cluster was obtained using t-butylcalix[4]arene as the ligand, which has extraordinary chemical stability and can act as a stable photocatalyst to catalyze the oxidation of ammonia to imine.

The self-assembly of giant hollow macrocyclic structures has been achieved through two novel tetratopic ligands. The bi-directional geometric mutual constraints were found to be the key factors controlling the giant hollow architectures.

Duck down, as a natural keratin material, has been widely used as a filling material. The multilevel bifurcation structure of down has been observed and characterized through scanning electron microscopy. The structure is a complex fractal structure composed of four-level self-similar structures including five units, that is, the calamus, main barb, barb, barbule, and node or prong. The differential friction effect of the dynamic friction coefficients of the barb was reduced from 0.4 (dry state) to 0.23 (wet state), namely a decrease of 42.5%. The friction locking effect decreases due to the swelling of the fiber diameter. The down is zero gravity in water, and under the action of vibration and internal stress, down that has been subjected to friction or heat setting treatment can quickly return to its original shape in water. This shape memory mechanism was further confirmed, in which down after heat setting can restore its shape to the natural state by shaking it quickly and vigorously. This research provides inspiration to investigate more complicated functions of natural materials and encourages the creation of very intelligent synthetic polymers.

Incorporating heterometal into titanium-oxygen clusters (TOCs) is an effective way to improve its catalytic activity. Herein, we synthesize three novel heterometallic TOCs with the formula of [Ti

Four new tris-Anderson polyoxometalates (POMs), (NH4)4[ZnMo6O18(C4H8NO3)(OH)3]·4H2O (1), (NH4)4[CuMo6O18(C4H8NO3)(OH)3]·4H2O (2), (TBA)3(NH4)[ZnMo6O17(C5H9O3)2(OH)]·10H2O (3) (TBA = n-C16H36N), and...

Silk fibroin (SF) material receives a great deal of attention in the biomedical field for its extensive mechanical performance and applications due to its singular structure/properties and applications, especially hierarchical structure. Here, we blended polyethylene glycol (PEG) into SF solutions that reconstruct the hierarchical micro structure of SF. The effect of PEG on the SF gelation process was in situ observed through rheological measurement and optical density changes. The structural change of SF/PEG blended films with different concentrations and their effects on the mechanical performance were investigated. The results indicated that with increasing PEG content, the β-sheet content of the films increased with the α-helix declining, which enables a composite film with a fracture strain exceeding 300%, Young's modulus exceeding 200 MPa and a fracture strength exceeding 20 MPa. The culture of MC-3T3 proves that the film is beneficial for cell proliferation and adhesion. By constructing the mesoscopic structure of SF, the plasticized silk materials provide great options for biodegradable and flexible protein-based materials.

Objective To observe the diastolic wall shear stress (WSS) pattern of the left ventricle (LV) by using vector flow mapping (VFM) in normal subjects. Methods A total of 371 healthy volunteers were recruited into this study and divided into four age groups. The LV WSS was measured at each diastolic phase, and the mapping of WSS was analyzed. Results Among groups I, II and III, The absolute value of WSS of Anterolateral，Inferoseptal and Anterospetal segments in phase D1；WSS values of inferolateral，Inferoseptal and Anterospetal segments in phase D4 all showed an increasing trend with age. In terms of gender differences, In most cases，women had greater diastolic WSS values compared to men. For each age group, the log-transformed WSS value appeared the increasing-decreasing-increasing trend from phase D1 to D4, with a peak value at the rapid filling phase.Multivariate backward stepwise linear regression analysis revealed that the certain segments log-transformed WSS was independently related to conventional parameters in evaluating diastolic function（mitral lateral E/e', septal E/e', mitral lateral e', septal e' and LAVI）.Conclusions In diastolic period, segmental LV WSS shows a regular variation phenomenon and has specific age- and gender-related patterns in different diastolic phases. The mapping of WSS may help identify the diastolic hemodynamic changes or diastolic function phase by phase.

A series of functional cation-regulated isopolymolybdate-based organic–inorganic hybrid compounds, Na2H2[Mo4O12(C8H17O5N)2]·10H2O (1), Na2[M(Bis-tris)(H2O)]2[Mo7O24]·10H2O [M = Cu, 2; Ni, 3; Co, 4;...

Two classic sandwich type selenotungstate derivates polyoxometalate [M2(Se2W19O67)(H2O)3]8− (M = CoII or MnII) have been successfully obtained and characterized. The compounds acted as promising co-catalyst of tetrabutylammonium bromide and promoted the conversion of carbon dioxide to a cyclic carbonate under mild reaction conditions.

Cu(II) and Zn(II) complexes with Schiff bases derived from diethylenetriamine, [Cu(C22H23N5)(H2O)(ClO4)2] (1), [Cu(C14H18N4)(ClO4)](ClO4) (2), and [Zn(C10H17N5Cl)]4[ZnCl4]2·H2O (3), have been synthesized and structurally characterized. The interactions of the complexes with CT-DNA were investigated by electronic absorption, circular dichroism (CD), and fluorescence spectroscopies. All three complexes appear to bind to DNA via groove binding modes. The order of DNA binding strength was 2 > 1 > 3. The complexes proved to be capable of efficient cleavage of pBR322 DNA at micromolar concentrations in the presence of ascorbic acid as a reducing regent. The hydroxyl radical may be the reactive species, and H2O2 may be involved in DNA strand breakage induced by these complexes. Furthermore, in vitro cytotoxicities of the complexes against four human carcinoma cell lines (HepG2, MGC-803, EC9706, and MCF-7) were screened by MTT assays. Complex 2 shows potent activity against HepG2 and MGC-803 cell lines; for all four cell lines, the activities of the complexes follow the order: 2 > 1 > 3. Hence, the different anticancer activities of the complexes may be correlated with their DNA binding abilities.

A carboxylate-driven assembly strategy has been developed for the first time to build calix[n]arene-based polyoxotitanate clusters with tuneable nuclearity and structures. Photocatalytic studies revealed that these clusters exhibit structural-dependent H2 evolution ability with a maximum rate up to 415.11 μmol h−1 g−1, which is almost the highest recorded in polyoxotitanate clusters.

With use of a macrocyclic polyphenol, tert-butylcalix[8]arene (TBC[8]), as ligands, a series of TBC[8]-stabilized {Ti4O2}clusters, containing penta- and hexacoordinated Ti centers, were synthesized. Such complexes are "core-shell" shaped containing a {Ti4O2} core arranged in a zigzag fashion. While outer walls of the clusters are decorated by deprotonated TBC[8], their upper and lower surfaces can be modified by various O- or N-donor ligands, and the ratio of the penta- and hexacoordinated Ti(IV) centers in the {Ti4O2} core can be precisely regulated from 4:0, to 3:1, to 2:2, to 1:3, and finally to 0:4. The combined coordination of different ligands in the axial direction shows significant influence on the adsorption of the TBC[8]-Ti4 system in the visible-light region, and their absorption edge can be precisely regulated from 600 to 700 nm. The above structural functionalization in the TBC[8]-Ti4 system also tunes their photocatalytic H2 production activities and oxidative desulfurization ability. Thus, for the first time, by confining the polyoxotitanium cluster in macrocyclic molecules, we provide an example of understanding the structure-property relationship of titanium-oxygen materials by ligand modification.

Three new coordination compounds containing 5‑diethylamino‑2‑((4‑(phenyldiazenyl) phenylimino) methyl) phenol ligand have been synthesized and fully characterized. Single crystal structure showed that the ligand shows multiple coordination mode and the phenyl group next to azo group could rotate during the coordination process. In Mn(HDAPPP)2Cl2·CH3CN (1), the HDAPPP behaved as a mono ligand because of the N of the imine group is protonated in the keto form and does not participate in coordination. While the Cu(DAPPP)2 (2) and Ni(DAPPP)2 (3) are classic complexes containing azo-Schiff base ligand. The fluorescence emission peaks of compounds indicated that the fluorescence of the compounds are mainly derived from the π-π* charge transition of the ligand and affected by the rotation of ligand. The UV–Vis data revealed that the compound 1–3 with the maximum absorption peak at 425 nm, 440 nm and 338 nm, respectively. This clearly confirmed that the compound 1 is mainly based on the keto configuration while the compound 3 is mainly based on the enol configuration. Z-scan experiments showed that all compounds exhibited reverse saturable absorption effect and self-defocusing effect for nonlinear optical materials. The nonlinear absorption coefficients (β) of compound 1–3 are evaluated to be 6 × 10−11 m·W−1, 4.4 × 10−11 m·W−1, and 1.7 × 10−11 m·W−1 respectively, and the nonlinear refraction coefficients (n2) are −1.4 × 10−17 m2·W−1, −1.6 × 10−17 m2·W−1, −7.0 × 10−18 m2·W−1 respectively. The nonlinear optical property of compound 1 and 2 are better than compound 3, which are influenced by ligand rotation after coordination.

Two new types of supramolecular aggregate co-crystals containing C70 and M(TPP), Co(TPP)·C70·1.5CS2 (1) and M(TPP)·C70·CS2 [M = Zn (2), 2H (3), TPP = tetraphenylporphyrin], were discovered by adjusting the synthetic parameters, and their inherent resistance measurement was utilized to study the intermolecular contact of these compounds for the first time. The results showed that the resistance was affected by the packing of the components as well the metal center of M(TPP) units, and the method could clearly be beneficial to the discovery of new aggregates with stronger interaction.

A new C60-polyoxometalate compound was synthesized by a C60 derivative with a {SiW11Mn} cluster connecting through a coordination bond and characterized. The photocurrent response test showed great improvement of this new compound compared to C60 and the polyoxometalate precursor, which could be used as a potential photoelectric material.

Introduction: Radiotherapy, combined regimens as platinum-paclitaxel chemotherapy and/or endocrine therapy is an important adjuvant treatment after surgery for endometrial cancer (EC). While, the resistance to them remain unclear. In our study, to separate the characteristics of side population (SP) cells from EC cell lines, study the mechanism of Taxol-resistance, progestin resistance and radioresistanc, and provide the basic for EC.Methods: SP cells from EC cell lines HEC-1A, Ishikawa and RL95-2 were separated by Hoechst 33342 staining and flow cytometry analysis. The expression of breast cancer resistance protein (BCRP) in SP cells and non-SP cells from HEC-1A was examined by immunocytochemistry, and the radiation-resistant and Taxol-resistant characteristics of SP cells and non-SP cells were compared by MTS. Ishikawa, Ishikawa-SP, and Ishikawa-non-SP cells incubated with MPA were selected for cell apoptosis assays by using flow cytometry. The expression of caspase-3 was examined by immunocytochemistry, and autophagy was detected by MDC staining.Results: Small proportions of SP cells, namely, 1.44 ± 0.93%, 2.86 ± 3.09%, and 2.87 ± 1.29%, were detected in HEC-1A, Ishikawa and RL95-2, respectively. There was a stronger clone formation efficiency for the SP cells than for non-SP cells in HEC-1A [(6.02 ± 1.17) vs. (0.53±0.20)%, P = 0.001], and there was a significant difference in the rate of tumourigenicity between the SP cells and non-SP cells in HEC-1A (87.5 vs. 12.5%). There were higher levels of BCRP expression (P = 0.001) and resistance to Taxol and radiation (P < 0.05) in the SP cells than in non-SP cells. After MPA treatment, the apoptosis rates were significantly different among the Ishikawa, Ishikawa-SP and Ishikawa-non-SP groups [(4.64 ± 0.18)%, (4.01 ± 0.43)%, and (9.3 ± 0.67)%; (P = 0.05)], and the expression of Caspase-3 in the Ishikawa group was higher than that in Ishikawa-SP group. The autophagic activity of the Ishikawa-SP cells was the strongest, while the autophagic activity of Ishikawa-non-SP was the weakest.Conclusions: There is a significant enrichment in SP cells among different EC cell lines, and these SP cells be more resistant to Taxol, MPA and radiation therapy. The overexpression of BCRP among SP cells may be the cause of resistance to Taxol, progestin and radiotherapy, which may be related to apoptosis and autophagic activity.

Polyoxometalate (POMs) are large group of discrete, mostly anionic polynuclear metal-oxo clusters amenable to a variety of chemical transformations. Because of high oxidation of the central metal, the original structure of POMs did not change after electron implantation. The electrons introduced during the reduction process can be immobilized on a certain metal or between the metal center and the titanium oxide metal ions. Compared with fully oxidized POMs, reduced POMs have different electron densities of oxygen atoms, so their coordination ability is different, which affects their physical and chemical properties. When synthesizing reduced POMs, some basic principle must be considered, such as whether the POMs system contains diversified structure points, whether the intermediate product has high enthalpy value, whether it has isomerization, whether the system can cover other metal ions should be considered, etc. According to the stability of reduced POMs, they can divided into three types: firstly each center metal contains only one end oxygen atom, second each center metal contains two end oxygen atoms, last the combination of the first two conditions. There are significant differences in the preparation methods of different types of reduced POMs. There are three kinds of common methods: photochemical reduction, control potential electrolysis and chemical oxidation reduction. Besides, hydrothermal synthesis, microwave synthesis and one pot synthesis were new approaches without specific reaction mechanism. With the injection of electrons in the system, different degrees of reduction and the way will be derived from new derivatives. The reduced POMs of various types of structures and corresponding typical examples are briefly introduced, and the application of reduced POMs in many aspects is discussed. In the field of traditional catalysis, reduced POMs in molecular devices, biological reagents and new application of energy materials has gradually begun to attract peoples attention. Chemists have long realized that the delocalized electrons of reduced POMs can produce magnetism, but the magnetic utilization work has just started, although there are a large number of heteropoly blue molecules. It has been reported, but only a few molecules have been studied as functional elements of magnet devices or spins. Scientists understanding of the biological activity of POMs is not very thorough, but research in this field is gradually deepening and systematic. Studies have shown that reduced POMs can exhibit higher biological activity relative to their oxidation states. There are many challenges in the study of reduced POMs from basic chemistry to molecular applications. However, the discovery and characterization of multi-molecular molecules has led to the refinement of POMs in the structural model, the clear relationship between structure and properties. The advantages are more obvious. Furthermore, the research on related materials will be more and more worthy of attention. It is believed that through unremitting efforts, the reduced POMs in future new material systems, such as molecular-based magnetic materials, nanotechnology, catalyst molecular-based energy storage devices and life. In areas such as learning, it will show its revolutionary potential and prospects.

The infrared image is corrupted by heavy Poisson noise in lowlight situation, which results in the loss of detail information. To suppress the heavy Poisson noise and keep the distinct edges of images in the lowlight situation, the denoising method based on the improved Anscombe transformation in wavelet domain is proposed. The Anscombe transformation in wavelet domain is improved to control the image distribution from Poisson into Gaussian distribution accurately; then the improved total variation regularization is applied to the wavelet-Anscombe domain for suppressing the heavy noise effectively with the optimal wavelet function. Denoising experiments on artificially degraded and practical lowlight infrared images show that the proposed denoising method can suppress the noise effectively and preserve the detail of images with heavy noise compared with several state-of-the-art methods.

Two polyoxomolybdates (DMAH)2.75Na1.25[H2Mo6O19(C7H7AsO3)2]·6H2O (1) and In0.5Na3.5[Mo12O34(C7H7AsO3)2]·16H2O (2) have been synthesized by the reactions of benzyl arsonate with molybdate in aqueous solution with the existence of In3+ ions and characterized. The [H2Mo6O19(C7H7AsO3)2]4− in 1 is a new derivative of Strandberg-Type cluster and compound 2 is 3D network which is constructed by “inverse-Keggin” cluster and In3+ and Na+ cations. Both of the compounds show efficient catalytic activity on selective oxidation of benzyl alcohol to benzaldehyde.

A pure inorganic 2D network molybdophosphate, [Mn3 Mo12 O24 (OH)6 (HPO3 )8 (H2 O)6 ]4- (1 a), synthesized through microwave irradiation with the existence of Mn2+ and organic cations and isolated as [(CH3 )2 NH2 ]3 Na[Mn3 Mo12 O24 (OH)6 (HPO3 )8 (H2 O)6 ]⋅12 H2 O (1), is found to possess highly enhanced performance in lithium-ion batteries' anode materials. The molecule shows multielectron redox properties suitable for producing anode materials with a specific capacity of 602 mA h g-1 at 100 mA g-1 after 50 cycles in lithium-ion batteries, although its specific capacity is the highest among all the reported pure inorganic 2D polyoxometalates to date, the cyclic stability is not that satisfactory. A hybrid nanocomposite of this 2D network and polypyrrole cations effectively reduces the capacity fading in initial cycles, and increases the stability and improves the electrochemical performance of lithium-ion batteries as well.