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Active deformation behavior reflects cell structural dynamics adapting to varying environmental constraints during malignancy progression. In most cases, cell mechanics is characterized by modeling using static equilibrium systems, which fails to comprehend cell deformation behavior leading to inaccuracies in distinguishing cancer cells from normal cells. Here, a method is introduced to measure the active deformation behavior of cancer cells using atomic force microscopy (AFM) and the newly developed deformation behavior cytometry (DBC). During the measurement, cells are deformed and allows a long timescale relaxation (≈5 s). Two parameters are derived to represent deformation behavior: apparent Poisson's ratio for adherent cells, which is measured with AFM and refers to the ratio of the lateral strain to the longitudinal strain of the cell, and shape recovery for suspended cells, which is measured with DBC. Active deformation behavior defines cancer cell mechanics better than traditional mechanical parameters (e.g., stiffness, diffusion, and viscosity). Additionally, aquaporins are essential for promoting the deformation behavior, while the actin cytoskeleton acts as a downstream effector. Therefore, the potential application of the cancer cell active deformation behavior as a biomechanical marker or therapeutic target in cancer treatment should be evaluated. [ABSTRACT FROM AUTHOR]

Hierarchical structured ZnFeO@reduced graphite oxide@TiO (ZnFeO@RGO@TiO) nanocomposite was prepared by an electrostatic layer-by-layer route, which played a synthetic effect of Fenton oxidation of ZnFeO and photocatalytic oxidation of TiO to degrade fulvic acid (FA) solution under visible-light irradiation. In this method, RGO, as the middle layer, can effectively promote the photo-induced electron flow between the ZnFeO and TiO and further improve the efficiency of the photo-Fenton oxidation. The influencing factors on photo-Fenton oxidation, including solution pH, catalyst, and HO dosage, have also been investigated. The results illustrated that the ternary composite presented the enhanced catalytic performance. Under visible light irradiation, the degradation efficiency of the sample on the FA solution can reach 95.4% within 3 h. In addition, the catalyst exhibited superior stability and reusability, and its degradation efficiency was still up to 90% after 5 cycles. Therefore, the composite will be a kind of efficient photocatalyst and had a promising application for visible-light driven destruction of organic pollutants. [ABSTRACT FROM AUTHOR]

Coiled carbon nanotubes (CCNTs) were coated by CoFe 2 O 4 (CFO) nanoparticles to form the CCNTs/CFO composites. The phase composition, morphology, electrical and magnetic performances of the composites were characterized by means of modern analytical techniques. The results indicated that the conductivity and magnetic performances of the samples were related to their compositions. The CCNTs/CFO composite with ω CCNT / ω CFO of 0.4 exhibited the best microwave absorption property in the prepared samples, whose minimum reflection loss was about −14 dB in the frequency range of 2–18 GHz for a layer of 2.5–3.0 mm thickness, and the available bandwidth corresponding to RL less than −10 dB can reach 4.0 GHz. Hence, the obtained composite could be used as a new candidate for selective frequency shielding and lightweight microwave absorbing material. [ABSTRACT FROM AUTHOR]

Ternary photocatalyst, reduced graphene oxide-ZnFe 2 O 4 -polyaniline (RZP), has been successfully developed by the in-situ polymerization of aniline on the reduced graphene oxide-ZnFe 2 O 4 (RG/ZF) surface for sewage purification. The SEM, TEM and STEM images suggest that PANI has coated the RG/ZF composite well. The XRD, TG-DTG and FT-IR analysis confirm that there are some interactions between RG/ZF composite and PANI. Importantly, the decontamination performance of RZP composites has been investigated using RhB as a model organic in view of adsorption and photocatalysis. On one hand, thermodynamic researches indicate that the adsorption behaviors of RZP composites conform to the Langmuir model, and their adsorption mechanism can be well described by the second-order kinetic model. On the other hand, RZP composites with different mass ratios of PANI to RG/ZF ( m P/RZ ) present a better photocatalytic activity than that of RG/ZF composites, and their photocatalytic behaviors under different pH could be described by the first-order kinetic model. Furthermore, it can be observed that the RZP composite with m P/RZ = 0.4 has the excellent photocatalytic activity and photocatalytic stability under pH = 1. Finally, the possible photocatalytic degradation mechanisms of the RZP composite on RhB have been discussed. These results can unveil that the prepared RZP photocatalyst is very promising for application in water purification. [ABSTRACT FROM AUTHOR]

Visible-light-absorbing compounds that generate reactive oxygen species in water are needed to maximize the degradation rate of organic dye under incident solar radiation. In this study, hollow ZnFe 2 O 4 and ZnFe 2 O 4 /TiO 2 composites were prepared by coprecipitation and microemulsion method, respectively. The structure and morphology of as-prepared samples as well as their magnetic properties and photocatalytic degradation activities on methyl orange and rhodamine B solution were investigated in detail. The results show that ZnFe 2 O 4 /TiO 2 composites have excellent performance on photocatalytic degradation of dye in wastewater under visible light. Especially, the photocatalytic degradation activity of the composite with ω TiO 2 25% on dye in wastewater was comparable to that of pure titanium dioxide (under UV light). Also, all samples show good stability, and are easy to recycle. This work demonstrates a cost-effective, recyclable, environment-friendly and simple way to directly degrade organic dye in wastewater by means of photocatalysis. [ABSTRACT FROM AUTHOR]

The composites formed by copolymer (N-methylpyrrole-co-pyrrole) and Ba 0.9 Nd 0.1 Cr 0.5 Fe 11.5 O 19 ferrite were prepared by in-situ solution polymerization. The phase, morphology, thermal stability, electrical conductivity, electromagnetic properties, and reflection loss of the as-prepared samples were characterized. The results revealed that the Ba 0.9 Nd 0.1 Cr 0.5 Fe 11.5 O 19 ferrite particles have been successfully coated by the (N-methylpyrrole-co-pyrrole) copolymer. The concentration of H 3 PO 4 can make a difference to the conductivities of the as-prepared samples, and affect their microwave absorbing properties. In addition, the composition and thickness of samples also had the remarkable influence on their microwave absorbing properties. What is more, the microwave absorbing properties of the poly(N-methylpyrrole-co-pyrrole)/Ba 0.9 Nd 0.1 Cr 0.5 Fe 11.5 O 19 composites were better than that of single-component counterparts, in which the minimum of reflection loss and the available bandwidth (the frequency width of reflection loss is less than −8 dB) of poly(NMPy-co-Py)/BNCF composite with m NMPy–Py / m BNCF of 5/3 and n NMPy / n Py of 1 at thickness of 2 mm reached to −26.57 dB and 8.36 GHz in the range of 2–18 GHz, respectively. This work suggested that composites could be used as the potential absorbing materials due to their excellent microwave absorbing properties. [ABSTRACT FROM AUTHOR]

Substrate stiffness has been proven to play a critical role in vitro tumor proliferation; however, pharmacological studies on antitumor drug screening are still routinely carried out in regular plastic culture plates. In the article, polydimethylsiloxane (PDMS) substrates with different stiffness (mimicking articular cartilage, collagenous bone and mammary tumor respectively) and plastic substrate were employed to establish the mechanical microenvironment for the in vitro drug screening platform. We studied the influences of stiffness on the responses of MCF-7 cells to typical antitumor drugs, cisplatin and taxol. Results showed that for both the treatment IC50 value to MCF-7 cells decreased significantly (p < 0.01) on the rigid substrate, indicating that MCF-7 cells on soft substrate have a resistance to cytotoxicity of antitumor drugs. The sensitivity of MCF-7 cells on rigid substrate to drug cytotoxicity was attributed to the increased cell cycle progression, implying that agents proven to be effective in vitro by conventional screening approach might be inefficient in a soft microenvironment in vivo. We conclude that stiffness of the substrates, as a critical mechanical factor, should be concerned for screening antitumor agents in vitro. As an extrapolation, the extensively used drug screening system needs to be revalued and redesigned. [ABSTRACT FROM AUTHOR]

The excellent photocatalytic activity of the sample was attributed to the synergistic effect of photocatalytic oxidation of TiO 2 , adsorption of RGO, Fenton oxidation of ZnFe 2 O 4 and its unique yolk-shell structure. [Display omitted] • The ZnFe 2 O 4 @RGO@TiO 2 with yolk-shell structure has good photocatalytic activity. • The ZnFe 2 O 4 @RGO@TiO 2 with magnetism is recycled and reused easily. • The ZnFe 2 O 4 @RGO@TiO 2 is promising for applications in wastewater treatment. ZnFe 2 O 4 @RGO@TiO 2 composites with a yolk-shell structure are successfully synthesized and systematically characterized with SEM, TEM, XRD and UV–vis. The catalytic degrading activities of the catalyst samples on RhB solution were evaluated under visible light irradiation. The test results have indicated that the catalytic activity of catalysts significantly influenced by many factors, such as cavity size of the catalyst, solution pH, catalyst and H 2 O 2 dosage. Under the optimum conditions, the degradation efficiency of the catalyst on the RhB is up to 94.3%. In addition, the catalyst exhibited a stable catalytic performance, maintaining its degradation efficiency up to 87.3% after five cycles. The prepared catalyst is promising for applications in wastewater treatment. [ABSTRACT FROM AUTHOR]

An important and difficult issue is simultaneously identifying the detailed locations of various molecules on the cell surface, as this identification requires a synergistic effect between more than one molecule in a living cell. Au nanoparticles (NPs) with different shapes can be readily recognised under low vacuum scanning electron microscopy (lvSEM). Anisotropic Au nanorods (NRs) possess unique surface plasmon resonance (SPR) properties, which can be further utilised for two photon luminescence (TPL) and other optical imaging techniques. In this paper, Au NRs and Au nanooctahedra (Au NOs) are introduced as biomarkers for ICAM-1 and Integrin β1. Combined with the advantages of lvSEM, this multiple-labelling method is a new method for studying the interactions between specific, functional molecules. [ABSTRACT FROM AUTHOR]

The micro/-nanoscaled functional biointerfaces aroused much interest of their key unit element to present unique functions. So far it is still difficult to describe the whole picture of this process. More and more evidences are beginning to support the theory of 'mirco/-nanotopography-coupled-mechanical (TCM) action' into functional biointerfaces. Herein, we aim to highlight TCM action on varied micro/-nanoscaled functional biointerfaces, namely to achieve better understanding of micro/-nanoscaled structures by introducing interfacial mechanical behaviors. In this article, recent progressions on 'TCM on air/liquid/solid-phase biointerfaces in nature', ' in vivo TCM behaviors at micro/-nanoscales', 'TCM in micro/-nanoscaled artificial surface with living Cells' and 'topography, interfacial curvature, mechanics' are reviewed. Certain new concepts of 'TCM action based on spatial curvature', 'medically functional biointerfaces' and 'biomechanopharmacology' are also proposed. [ABSTRACT FROM AUTHOR]

Background: The mechanical properties of cellular microenvironments play important roles in regulating cellular functions. Studies of the molecular response of endothelial cells to alterations in substrate stiffness could shed new light on the development of cardiovascular disease. Quantitative real-time PCR is a current technique that is widely used in gene expression assessment, and its accuracy is highly dependent upon the selection of appropriate reference genes for gene expression normalization. This study aimed to evaluate and identify optimal reference genes for use in studies of the response of endothelial cells to alterations in substrate stiffness. Methodology/Principal Findings: Four algorithms, GeNormPLUS, NormFinder, BestKeeper, and the Comparative ΔCt method, were employed to evaluate the expression of nine candidate genes. We observed that the stability of potential reference genes varied significantly in human umbilical vein endothelial cells on substrates with different stiffness. B2M, HPRT-1, and YWHAZ are suitable for normalization in this experimental setting. Meanwhile, we normalized the expression of YAP and CTGF using various reference genes and demonstrated that the relative quantification varied according to the reference genes. Conclusion/Significance:: Consequently, our data show for the first time that B2M, HPRT-1, and YWHAZ are a set of stably expressed reference genes for accurate gene expression normalization in studies exploring the effect of subendothelial matrix stiffening on endothelial cell function. We furthermore caution against the use of GAPDH and ACTB for gene expression normalization in this experimental setting because of the low expression stability in this study. [ABSTRACT FROM AUTHOR]

BiVO samples doped with different amounts of La or Zn ions have been synthesized successfully by a hydrothermal method, and their composition, microstructure and photocatalytic activity were characterized by means of modern analytical techniques. The results illustrated that these doped BiVO samples presented a better photocatalytic performance than the undoped BiVO sample, among which BiLaVO and BiZnVO exhibited the highest degradation efficiency. Under visible light illumination, their photocatalytic degradation on RhB was up to 95.4 and 98.56% in 60 min, respectively. In particular, the BiLaVO and BiZnVO had a good stability and still retained the photocatalytic activity of 93.7 and 94% after five cycling test. These results confirmed that the La/Zn -doped BiVO samples were a kind of efficient and stable visible-light-driven photocatalysts and had a promising application for the degradation of organic contaminant. [ABSTRACT FROM AUTHOR]