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Several isostructural lanthanide metal–organic frameworks, viz. [Ln(DCHB)1.5phen]n(Ln-MOFs, where Ln = Eu for 1, Tb for 2, Sm for 3and Dy for 4), are successfully synthesized through the hydrothermal reactions of 4′-di(4-carboxylphenoxy)hydroxyl-2, 2′-bipyridyl (H2DCHB) and lanthanide nitrates as well as chelator 1,10-phenantroline (phen). These structures are characterized by single-crystal X-ray diffraction, and the representative Ln-MOF 1is a fivefold interpenetrated framework with the uncoordinated Lewis base N sites form DCHB2–ligands. The photoluminescence research studies reveal that Ln-MOFs 1–4exhibit characteristic fluorescent emissions from ligand-induced lanthanide Ln(III) ions, while the single-component emission spectra of Ln-MOF 4are all located in a white region under different excitations. The absence of coordinated water and the interpenetration property of the structures are conducive to the structure rigidity, and the results display that Ln-MOF 1has high thermal/chemical stabilities in common solvents and a wide pH range as well as the boiling water. Notably, luminescent sensing studies reveal that Ln-MOF 1with prominent fluorescence properties can perform in highly sensitive and selective sensing of vanillylmandelic acid (VMA) in aqueous systems (KSV= 562.8 L·mol–1; LOD = 4.6 × 10–4M), which can potentially establish a detection platform for the diagnosis of pheochromocytoma via multiquenching mechanisms. Moreover, the 1@MMMs sensing membranes comprised of Ln-MOF 1and a poly(vinylidene fluoride) (PVDF) polymer can also be facilely developed for VMA detection in aqueous media, suggesting the enhanced convenience and efficiency of practical sensing applications.

Bacterial infections pose mounting public health concerns and cause an enormous medical and financial burden today. Rapid and sensitive detection of pathogenic bacteria at the point of care (POC) remains a paramount challenge. Here, we report a novel concept of bacteria-instructed click chemistry and employ it for POC microbial sensing. In this concept of bacteria-instructed click chemistry, we demonstrate for the first time that pathogenic bacteria can capture and reduce exogenous Cu2+to Cu+by leveraging their unique metabolic processes. The produced Cu+subsequently acts as a catalyst to trigger the click reaction between gold nanoparticles (AuNPs) modified with azide and alkyne functional molecules, resulting in the aggregation of nanoparticles with a color change of the solution from red to blue. In this process, signal amplification from click chemistry is complied with the aggregation of functionalized AuNPs, thus presenting a robust colorimetric strategy for sensitive POC sensing of pathogenic bacteria. Notably, this colorimetric strategy is easily integrated in a smartphone app as a portable platform to achieve one-click detection in a mobile way. Moreover, with the help of the magnetic preseparation process, this smartphone app-assisted platform enables rapid (within 1 h) detection of Escherichia coliwith high sensitivity (40 colony-forming units/mL) in the complex artificial sepsis blood samples, showing great potential for clinical early diagnosis of bacterial infections.

ABSTRACTIntroduction: Chemotherapy plays an important role in antitumour therapy, but causes serious adverse reactions. So, drug delivery system (DDS) with cell-targeting ability is an important method to reduce adverse reactions while ensuring the effectiveness of chemotherapy. Synthetic drug carriers and DDSs based on cells have proven safety and efficacy, but they also have many deficiencies or limitations. Cell membrane capsules (CMCs), which are based on extracellular vesicles (EVs), are a promising biomimetic DDS that retains some cell membrane channels and cytoplasmic functions, with escape macrophage phagocytosis.Areas covered: The EVs for constructing CMCs can be prepared by natural secretion, chemical-induced budding, nanofilter membrane extrusion and similar methods and are isolated and purified by a variety of methods such as centrifugation and liquid chromatography. CMCs can target the tumour cells either spontaneously or through targeting modifications using proteins or aptamers to actively target the tumour cells. CMCs can be directly wrapped with chemicals, photosensitizers, RNA, proteins and other ingredients, or they can be loaded with antitumour agent-loaded synthetic nanoparticles, which are delivered to the target cells to play a specific role.Expert opinion: This review describes the concept, function, characteristics, origins, and manufacturing methods of CMCs and their application in antitumour therapy.

ABSTRACTIntroduction: Ceramide is a bioactive lipid which functions as a tumor suppressor, regulating processes such as cell proliferation, differentiation, senescence and apoptosis. However, several challenges need to be overcome in order to realize the therapeutic potential of such a bioactive lipid combination regimen, including the hydrophobic and hemolytic nature of the lipids.Areas covered: In this review, we briefly describe the biological function of ceramide, then the delivery systems that have been developed to improve the pharmacology of ceramide have been summarized. In addition, combination therapies based on these delivery systems to reveal the interactions between therapeutic drugs and ceramide were also highlighted. Furthermore, future perspective before the extension of ceramide’s applications in cancer treatment will also be discussed.Expert opinion: Although ceramide has attracted tremendous attention in targeted cancer treatment, its levels are usually suppressed by over-expression of ceramide-metabolizing enzymes or down-regulation of ceramide-generating enzymes. Thus, finding ways to increase ceramide by exogenous treatment in cancer cells is desired. Therefore, translating these bioactive lipids into clinical usage requires a variety of methods, and appropriately designed delivery systems may play the direct and important role in this process.

ABSTRACTIntroduction: Toll-like receptors (TLRs) are expressed by a wide variety of cell types including immune cells. They play a crucial role in the inflammatory and host defense response against microorganisms, and triggering TLRs can mediate the activation of innate immunity. Furthermore, research suggests that various TLRs may function differently on different tumor cells. The change in TLR activity may elicit an anti-tumor activity in hepatocellular carcinoma (HCC) cells and may serve as a novel therapeutic target for HCC therapy.Areas covered: This review discusses the role of the TLR family in HCC and the underlying signaling pathway of TLRs as a form of pattern recognition receptor in mediating inflammation and HCC immunity responses. Agonists and antagonists of TLRs, which render TLRs as potential therapeutic targets, activate downstream molecules, subsequently causing HCC cell survival. The proliferation or protection against the development of HCC is also described.Expert opinion: A series of studies have highlighted a crucial role of TLRs in HCC and consider TLR signaling pathways as potential therapeutic targets for HCC. However, the conclusions of these studies are in part paradoxical and controversial. Thus, it is necessary to extend further research to help determine the signaling pathways involved.

Fabricated straw brick is a new wall material, its character is a kind of sandwich structure with tenon and groove, and wall assembly does not require any additional connections. Experiment and calculation have done to study the thermal parameters of fabricated straw brick and environmental protection performance of building in this material. The results show that straw wall’s heat transfer coefficient is much lower than that of normal concrete block and lightweight aggregate concrete block, which can guarantee good insulation performance. It was proved to have good thermal insulation in the further computational analysis. Therefore, it is a kind of environmental protection building material.

Reperfusion is the key strategy in acute ST-segment elevation myocardial infarction (STEMI) care, and it is time-dependent. Shortening the time from symptom to reperfusion and choosing the optimal reperfusion strategy for STEMI patients are great challenges in practice. We need to improve upon the problems of low reperfusion rate, non-standardized treatment, and economic burden in STEMI care. This article briefly reviews the current status of reperfusion strategy in STEMI care, and also introduces what we will do to bridge the gap between the guidelines and implementation in the clinical setting through the upcoming China STEMI early reperfusion program.

Bolted steel-wood-steel connection is an important fashion of connections in timber structure, the manners of failure loaded parallel-to-grain include bearing, row shear-out, group tear-out and splitting, and the brittle failure modes are predominant in some tested results of bolted connections specimens. End distance, bolt spacing, row spacing and the thickness of wood have important influence on the failure modes, and meanwhile, the bolt diameter can not be neglected. Based on the different failure fashion, the equations of strength were given.

Considering bamboo as a 2-phase natural composite made up of vascular bundles (reinforcement or fiber) and matrixes (ground tissues) on the scale of micromechanics. By test of bamboo specimens and analysis of microscopic images of their cross sections, the distribution of vascular bundles along the axial and radial of bamboo culm were investigated. The relations between tensile properties of bamboo and its distribution of vascular bundles were studied. The results show that the vascular bundles are graded distributing along the radius of bamboo culm. The volume fraction of vascular bundles is larger near the outside, and attenuates rapidly to about 40 percent of that at the location away from outer side about 1/3 thickness of bamboo culm, and than slowly reduces to 0 near the inner side of culm. In axial direction, the volume fraction of vascular bundles in the bottom culm is smaller than that in the middle culm where the volume fraction is less variation, and reaches the largest value at the top culm. The tensile moduli and strength of bamboo are linearly related to the volume fraction of vascular bundles. The tensile moduli and the strength of vascular bundle are largely grater than that of matrix. The stiffness and the strength of bamboo are mainly offered by vascular bundles.

The formulas to define the minimum ratio of length-to-thickness of the pier cross section of short-pier shear wall is presented, by which the short pier shear wall is distinguished from the irregular cross-section column frame numerically. According to the results of finite element analysis of typical short-pier shear walls, the elastic mechanical performances of them were investigated. Conclusions were achieved that the flange width hardly influence on the moment of piers but significantly influence on the magnitude of stresses in the horizontal section and the top displacements of walls; the deflection curve of short-pier shear wall is flexural-shearing type, equations and diagrams to define the position of the contra-flexural point in the curve are provided.

In this paper both a hollow floor and the corresponding solid floor are analysed by using finite element software and the results are compared. The comparison is made through a detailed finite element study between a column-supported cast-in-situ hollow floor filled by tube with its solid counter-part. The orientation of the tube fillers causes the stiffness of the hollow slab to be orthotropic, potentially changing the distribution of load carrying between the two orthogonal directions. The inclusion of the hollows also potentially increases the flexibility of the slab. Recommendations for design of column-supported cast-in-situ concrete floors compared with the solid floor are then made with respect to distribution of design moments and calculation of deflections. Thus the reference was given to the designer.

Statical analysis of infilled frame structure was conducted on 3D finite element models by means of software ANSYS10.0. Analyses on relevant parameters of infilled frame walls with or without openings have been carried out seperately, and it is found that the relevant stiffness of the model gradually increases with the ratio of the wall’s width to its height. However, the effection of the width to height ratio of the wall on its structural lateral stiffness becomes much smaller when the value of the width to height ratio is larger than 1.5. The effection can be basically ignored when the width to height ratio is larger than 1.8. It is investigated that the ratio of posts inertia moment to beams has great influence on model’s relevant stiffness. The relevant stiffness of frame structure decreases with the growth of the ratio of posts inertia moment to beams (I2/I1). For a long time, Filling Wall is widely used in multi-storey buildings and Civil Construction Structures, for its flexible architecture flats and large interior space, etc. However, because of the imperfection in analysis methods and the defects in model, pure- framework design is used in civil architectures, and the weight of filling wall is calculated by converting to the Line Load on the beam. According to the analysis of 5.12 Wenchuan earthquake[1], the early filling wall absorbs a large earthquake because of its stiffness, while its Adhesive Tensile Strength is low, which making the earthquake-damage to the filling wall is more serious than that to the frame structure. By analyzing the parameters in non-opening and opening filling wall and changing a given parameter, while keeping other parameters unchanged. This paper studies the influence on the Lateral Stiffness of Frame Structure, to provide Earthquake Fortifying Areas with reference data in the design process of filling wall.