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Metal–organic frameworks (MOFs) with fit ligands and metals can be integrated into electrochemical biosensors for the detection of various biomolecules. In this study, we have synthesized novel magnetic MOF composites as electrocatalysts and constructed a novel biosensor for electrochemical detection of dopamine. The composites named Fe3O4@ZIF-8@AuNPs–COOH are synthesized through layer-by-layer assembly. They exhibit excellent stability and cooperative catalytic activity. In addition, green recycling is readily achieved through magnetizing/demagnetizing the electrode. The large specific surface area and ordered porous structures of the magnetic MOFs ensure good dispersion of gold nanoparticles, while the carboxyl group efficiently shields other redox-active interfering substances. The proposed electrochemical biosensor accomplishes the sensitive detection of dopamine in human serums and living cells. This study broadens the application of MOFs in electrochemical biosensing, validates the feasibility of biosensors for in vivo analysis, and provides new insights into green sensing. [ABSTRACT FROM AUTHOR]

Rational design of γ-alumina-based catalysts relies on an extensive understanding of the distribution of hydroxyl groups on the surface of γ-alumina and their physicochemical properties, which remain unclear and challenging to determine experimentally due to the structural complexity. In this work, by means of DFT and thermodynamic calculations, various hydroxylation modes of γ-alumina (110) and (100) surfaces at different OH coverages were evaluated, based on which a thermodynamic model to reflect the relationship between temperature and the surface structure was established and the stable hydroxylation modes under experimental conditions were predicted. This enables us to identify the experimentally measured IR spectra. The effect of hydroxyl coverages on the surface Lewis acidity was then analyzed, showing that the presence of hydroxyl groups could promote the Lewis acidity of neighboring Al sites. This work provides fundamental insights into the molecular level understanding of the surface properties of γ-alumina and benefits the rational design of alumina-based catalysts. [ABSTRACT FROM AUTHOR]

Treatment of Yb(II) complex [L2Yb(THF)2] (L = PhC(NSiMe3)2) with elemental sulfur, selenium or tellurium resulted in the isolation of a series of dinuclear Yb(III) complexes featuring side-on bound S32− (1), Se22− (2) or Te22− (3) moieties, respectively. Magnetic study on these complexes revealed that 3 is a rare lanthanide telluride single-molecule magnet (SMM). [ABSTRACT FROM AUTHOR]

Novel materials displaying multiple exceptional properties are the backbone of the advancement of various industries. In the field of carbon materials, the combination of different properties has been extensively developed to satisfy diverse application scenarios, for instance, conductivity paired with exceptional hardness, outstanding toughness coupled with super-hardness, or heat resistance combined with super-hardness. In this work, a new carbon allotrope, bcc-C40 carbon, was predicted and investigated using first-principles calculations based on density functional theory. The allotrope exhibits unique structural features, including a combination of sp3 hybridized diatomic carbon and four-fold carbon chains. The mechanical and dynamic stability of bcc-C40 carbon has been demonstrated by its elastic constants and phonon spectra. Additionally, bcc-C40 carbon exhibits remarkable mechanical properties, such as zero homogeneous Poisson's ratio, superhardness with a value of 58 GPa, and stress-adaptive toughening. The analysis of the electronic properties demonstrates that bcc-C40 carbon is a semiconductor with an indirect band gap of 3.255 eV within the HSE06 functional, which increases with the increase in pressure. At a pressure of 150 GPa, bcc-C40 carbon transforms into a direct band gap material. These findings suggest the prospective use of bcc-C40 carbon as a superhard material and a novel semiconductor. [ABSTRACT FROM AUTHOR]

Direct access to trans–cis photoisomerization in a metastable state photoacid (mPAH) remains challenging owing to the presence of competing excited-state relaxation pathways and multiple transient isomers with overlapping spectra. Here, we reveal the photoisomerization dynamics in an indazole mPAH using time-resolved fluorescence (TRF) spectroscopy by exploiting a unique property of this mPAH having fluorescence only from the trans isomer. The combination of these experimental results with time-dependent density function theory (TDDFT) calculations enables us to gain mechanistic insight into this key dynamical process. [ABSTRACT FROM AUTHOR]

Lithium–sulfur batteries have garnered significant interest as potential energy storage systems for the future, owing to their remarkable theoretical specific capacity (1675 mA h g−1) and energy density (2600 W h kg−1). However, their development has been severely impeded by several challenges, including the low intrinsic conductivity of sulfur, volume expansion issues, and the polysulfide shuttle effect. To address these issues, polar metal compounds with nanostructures featuring hollow shells and catalytic functions have emerged as promising materials for designing advanced lithium–sulfur batteries. In this study, bimetallic selenides with varying degrees of hollowness are synthesized using a tannic acid etching and selenization strategy. By comparing the electrochemical characteristics of composite electrodes with different degrees of hollowness, an optimal semi-hollow core–shell structure is identified, implying that reasonable structural designing of metal compounds carries immense importance in improving electrochemical reactions. Moreover, the appropriate degree of hollowness effectively mitigates volume expansion issues associated with the sulfur cathode. Consequently, bimetallic selenides with a hollow core–shell structure coated with conductive MXene material exhibit superior electrochemical performance. The synergistic effect achieved through the judicious design of the hollow core–shell structure and the utilization of polar metal compounds has proved instrumental in enhancing the redox kinetics of lithium–sulfur batteries. As such, this research presents a novel avenue for the development of high-performance lithium–sulfur batteries. [ABSTRACT FROM AUTHOR]

A new family of reversible fluorescent adhesives based on Diels–Alder covalent adaptable networks with dynamic AIE crosslinks was developed. The accurate intrinsic correlation between the emission behavior, cross-linking state, and adhesion capability can be established, enabling the in situ visualization of adhesion capacity. [ABSTRACT FROM AUTHOR]

To overcome the effect of high actuation voltages causing dielectric elastomer films to breakdown, fabricating films with excellent dielectric properties and high durability is the current focus. Previously reported dielectric elastomer films, nevertheless, still require better dielectric properties and suffer from a lack of self-healing properties, which reduces the service life of the films. In this work, polysulfide polyurethane–urea (PSPU) elastomers with self-healing properties were synthesized through the insertion of dynamic disulfide bonds into the polymer chain segments via hydrogen transfer reactions. In addition, PSPU-based composites were fabricated in which the filler was MXene loaded with CeO2 obtained using a hydrothermal method. Benefiting from dynamic disulfide bonding and multiple hydrogen bonding interactions, PSPU attained a self-healing efficiency of 95%. Moreover, the 5.25 vol% CeO2@MXene/PSPU composite exhibited a dielectric constant of 206 at 100 Hz, maintaining a loss of 0.19 while having a self-healing efficiency of 97.9%. In contrast to PSPU, the dielectric constant of 5.25 vol% CeO2@MXene/PSPU was 34 times higher than that of the former at 100 Hz. These distinctive properties promise to render the films an integral part of the actuator. [ABSTRACT FROM AUTHOR]

Compared with traditional structure prediction methods, the purposeful bottom-up approach is better able to obtain structures with specified performance. In this study, we established two novel carbon phases in purely sp2-bonded networks, termed H61-carbon and H62-carbon, using a self-assembling approach. These carbyne-connected carbon allotropes had helix chains joined by cumulative double-bond chains. We certified the new carbon allotropes to be dynamically and mechanically stable. Both of these carbon allotropes exhibited excellent mechanical properties, and they had metallic and superconductive characteristics featuring superconducting transition temperatures of 10 K (H61-carbon) and 7.4 K (H62-carbon), respectively. These results provide an important strategy for the design of novel carbon allotropes with specified properties. [ABSTRACT FROM AUTHOR]

Hierarchical MoS2/graphene (MoS2/G) has been widely researched in energy storage via supercapacitors. The combination of MoS2 with graphene not only provides high conductivity but also enhances the structural stability, which are critical factors determining the electrochemical performance for energy storage. In this review, the recent development of various hierarchical MoS2/G nanostructures in supercapacitor applications is summarized by classifying the materials into MoS2/G nanospheres, MoS2/G nanosheets, and MoS2/G-based ternary composite. The description of the structural characteristics and electrochemical performance gives a clear and profound understanding of hierarchical MoS2/G nanostructures as a supercapacitor material. In addition, further research prospects of hierarchical MoS2/G are suggested. [ABSTRACT FROM AUTHOR]

g-C3N4 is introduced to the PEO electrolyte as a mediator to stabilize the interface to lithium metal anode. As a result, the interface resistance is stabilized after cycling and the symmetric cell exhibits a cycle life over 900 h, indicating that the interface stability is evidently promoted. [ABSTRACT FROM AUTHOR]

The development of a NIR-II (near-infrared-II: 1000–1700 nm) nanophotoswitch is urgently needed, due to its deeper tissue penetration and higher resolution imaging. In this work, a new type of NIR-II upconversion (UC) and downconversion (DC) nanophotoswitch (NaErF4:Ho@NaYF4@NaYbF4:Tm@NaYF4 core–multishell nanoparticles) is presented. When the switch is open, ultraviolet (UV)–blue emissions and intense red UC (Er3+:654 nm) and NIR-II DC (Er3+:1520 nm) emissions are simultaneously obtained under 980 nm NIR-I (near-infrared-I: 700–1000 nm) excitation, which shows potential application for real-time visible- and NIR-II-imaging in the photodynamic therapy (PDT) process. When the switch is closed, UV–blue emissions disappear while red UC (Er3+:654 nm) and NIR-II UC (Ho3+:1154 nm) emissions remain under 1532 nm NIR-II excitation, which may be used for real-time visible- and NIR-II-imaging before conducting PDT. This novel NIR-II nanophotoswitch displays special advantages in the biomedical field. [ABSTRACT FROM AUTHOR]

Hierarchical MoS2 nanostructures are of increasing importance in energy storage via batteries or supercapacitors. Herein, the various hierarchical MoS2 materials used as electrochemical electrodes are reviewed in detail by classifying the MoS2 into free-standing and substrate-supported hierarchical structures. The growth methods, morphologies, surface area, and electrochemical performance of the hierarchical MoS2 structures, including nanospheres, nanotubes, and nanoboxes are highlighted. Ascribed to the porous features and interconnected nanosheets, the hierarchical architectures demonstrated a large surface area and high structural stability, resulting in a high rate capacity and long cycling life. Based on the spotlight of applications for electrochemical energy storage, the recent progress of hierarchical MoS2 with efficient electrochemical properties is reviewed. Moreover, further research prospects and challenges of hierarchical MoS2 in energy storage are proposed. [ABSTRACT FROM AUTHOR]

In this critical review, hierarchical Bi2MoO6 nanostructures as photocatalysts for photocatalytically degrading organic materials are summarised in detail. Hierarchical nanostructures have attracted much attention due to their multiple advantages such as a porous structure, large surface area, efficient light harvesting and charge separation, which have considerable influences on the photocatalytic performance. Herein, the recent progress of hierarchical Bi2MoO6 nanostructures including primary, secondary and multiple structures is highlighted. Particularly, the morphologies, photocatalytic performance and mechanism of hierarchical Bi2MoO6 nanostructures are outlined. Finally, further development prospects of Bi2MoO6 photocatalysts are suggested. Hence, this systematic overview of hierarchical Bi2MoO6 will offer guidelines for designing efficient photocatalysts for environmental applications. [ABSTRACT FROM AUTHOR]

Organic homostructures with tunable physiochemical properties were fabricated by simply changing the isomer molecules via the "cocrystal engineering" approach. The morphology of the cocrystals can be changed into rod-like or branched, with superior waveguide and multi-directional waveguide performance, respectively, which contributes to the realization of optical waveguide modules with integrated functions. [ABSTRACT FROM AUTHOR]

There have been extensive studies on the application of topography in the field of tissue repair. A common feature of these studies is that the existence of topological structures in tissue repair scaffolds can effectively regulate a series of behaviors of cells and play a positive role in a variety of tissue repair and regeneration processes. This review focuses on the application of topography in the field of peripheral nerve repair. The integration of the topological structure and biomaterials to construct peripheral nerve conduits to mimic a natural peripheral nerve structure has an important role in promoting the recovery of peripheral nerve function. Therefore, in this review, we systematically analysed the structure of peripheral nerves and summarized the effects of topographic cues of different scales and shapes on the behaviors of nerve cells, including cell morphology, adhesion, proliferation, migration and differentiation. Furthermore, the application and performance of scaffolds with different topological structures in peripheral nerve repair are also discussed. This systematic summary may help to provide more effective strategies for peripheral nerve regeneration (PNR) and shed light on nervous tissue engineering and regenerative medicine. [ABSTRACT FROM AUTHOR]

Nonlinear optical microscopy that leverages an objective based total internal reflection (TIR) excitation scheme is an attractive means for rapid, wide-field imaging with enhanced surface sensitivity. Through select combinations of distinct modalities, one can, in principle, access complementary chemical and structural information for various chemical species near interfaces. Here, we report a successful implementation of such a wide-field nonlinear optical microscope system, which combines coherent anti-Stokes Raman scattering (CARS), two-photon fluorescence (TPF), second harmonic generation (SHG), and sum frequency generation (SFG) modalities on the same platform. The intense optical fields needed to drive these high order nonlinear optical processes are achieved through the use of femtosecond pulsed light in combination with the intrinsic field confinement induced by TIR over a large field of view. The performance of our multimodal microscope was first assessed through the experimental determination of its chemical fidelity, intensity and polarization dependences, and spatial resolution using a set of well-defined model systems. Subsequently, its unique capabilities were validated through imaging complex biological systems, including Hydrangea quercifolia pollen grains and Pantoea sp. YR343 bacterial cells. Specifically, the spatial distribution of different molecular groups in the former was visualized via vibrational contrast mechanisms of CARS, whereas co-registered TPF imaging allowed the identification of spatially localized intrinsic fluorophores. We further demonstrate the feasibility of our microscope for wide-field CARS imaging on live cells through independent characterization of cell viability using spatially co-registered TPF imaging. This approach to TIR enabled wide-field imaging is expected to provide new insights into bacterial strains and their interactions with other species in the rhizosphere in a time-resolved and chemically selective manner. [ABSTRACT FROM AUTHOR]

The development of Ho-based red-emitting upconversion (UC) nanoparticles with small size is of great significance in scientific research and practical application. Besides, a time-saving and environment-friendly strategy for the synthesis of core–multishell UC nanoparticles is urgently needed. In this work, small NaHoF4@NaYF4:Tb@NaGdF4:Yb,Tm@NaYF4 core/shell/shell/shell nanoparticles were successfully prepared by a modified co-precipitation method, in which sequential growth of shells could be realized. By means of Tb3+-mediated interfacial energy transfer (IET) and energy migration (EM), a novel mechanism for Ho-based red UC emission is presented under the premise of a small core size and thin shell. In the system, Ho-based red dominant emission mainly comes from the cross-relaxation process among Ho3+, which is induced by IET from Tb3+ to Ho3+. The EM process among Tb3+ can facilitate efficient energy transport. Furthermore, a mouse experiment demonstrates the deep penetration of 980 nm excitation and Ho-based red dominant emission. This new type of Ho-based red-emitting core–multishell UC nanoparticles not only provides an in-depth understanding of the IET-mediated energy-managing strategy but also displays special advantages in biomedical applications. [ABSTRACT FROM AUTHOR]

Currently, the red-to-UV-blue (R/U) ratio in the existing upconversion (UC) nanophotoswitches is too low to effectively realize real-time monitoring/imaging during the photodynamic therapy (PDT) process. Besides, the imaging depth is quite limited by using the NIR-I excitation (NIR-I = the first near-infrared biological window: 700–1000 nm), which cannot effectively determine the location of cancer cells before the induction of PDT. In this work, a novel NaErF4:0.5%Tm@NaYF4@NaYbF4:0.2%Tm@NaYF4 UC core–multishell nanophotoswitch is presented. For this Nd3+-free nanophotoswitch design, on the premise of ensuring the optimum intensity of UV-blue emission, red UC emission intensity is significantly enhanced under dual-NIR excitations. When the switch is turned off (before the induction of PDT), UV-blue emissions are turned off and red emission is left for real-time imaging under 1532 nm NIR-II excitation (NIR-II = the second near-infrared biological window: 1000–1700 nm), due to which the location of cancer cells can be effectively determined. When the switch is turned on, UV-blue and red emissions are simultaneously turned on with a high R/U ratio for PDT and real-time monitoring/imaging under 980 nm NIR-I excitation. This new type of UC nanophotoswitch can not only realize real-time imaging, but also simultaneously realize PDT and real-time monitoring/imaging, demonstrating the distinct advantages in bioapplications. [ABSTRACT FROM AUTHOR]

In this study, hierarchical MoS2/MoO3 nanotubes are fabricated through an elegant method. MoO3 nanorods serve as not only growth templates but also Mo precursors. It is well established that bubble-like MoS2 hollow nanospheres are uniformly distributed on the MoO3 nanotubes. Ascribed to the unique architecture and synergistic effect of active materials, the as-prepared hierarchical MoS2/MoO3 nanotubes exhibit excellent electrochemical performance for energy storage. This work sheds light on the design of hybrid hierarchical nanotubes as electrochemical electrode materials through an elegant and feasible strategy, providing an idea for fabricating hybrid materials with a high capacitive ability. [ABSTRACT FROM AUTHOR]

Well-ordered hierarchical Ag/Bi2MoO6 hollow nanoboxes are obtained through an artful hydrothermal method. Ag3PO4 nanocubes serve as growth templates and precursor sources of Ag. Ag3PO4 is reduced to Ag nanoparticles, which are dispersed on the nanosheet-built hierarchical Bi2MoO6 nanoboxes. With the investigation of intermediate products, the growth process of Ag/Bi2MoO6 is studied. Due to the hierarchical hollow structure and the introduction of Ag, the Ag/Bi2MoO6 nanoboxes exhibit enhanced visible-light absorption and photocatalytic performance compared to the pristine Bi2MoO6 microboxes. [ABSTRACT FROM AUTHOR]

Phenyl selenosulfide (PhS-SePh) is synthesized by an exchange reaction between phenyl disulfide and diselenide. PhS-SePh possesses average values of lattice parameters, bond character, and the lowest unoccupied molecular orbital as expected, but displays a higher discharge voltage plateau and much better cycling stability than the two precursors in rechargeable lithium batteries. [ABSTRACT FROM AUTHOR]

Zero-dimensional (0D) halides perovskites, in which anionic metal-halide octahedra (MX6)4− are separated by organic or inorganic countercations, have recently shown promise as excellent luminescent materials. However, the origin of the photoluminescence (PL) and, in particular, the different photophysical properties in hybrid organic–inorganic and all inorganic halides are still poorly understood. In this work, first-principles calculations were performed to study the excitons and intrinsic defects in 0D hybrid organic–inorganic halides (C4N2H14X)4SnX6 (X = Br, I), which exhibit a high photoluminescence quantum efficiency (PLQE) at room temperature (RT), and also in the 0D inorganic halide Cs4PbBr6, which suffers from strong thermal quenching when T ＞ 100 K. We show that the excitons in all three 0D halides are strongly bound and cannot be detrapped or dissociated at RT, which leads to immobile excitons in (C4N2H14X)4SnX6. However, the excitons in Cs4PbBr6 can still migrate by tunneling, enabled by the resonant transfer of excitation energy (Dexter energy transfer). The exciton migration in Cs4PbBr6 leads to a higher probability of trapping and nonradiative recombination at the intrinsic defects. We show that a large Stokes shift and the negligible electronic coupling between luminescent centers are important for suppressing exciton migration; thereby, enhancing the photoluminescence quantum efficiency. Our results also suggest that the frequently observed bright green emission in Cs4PbBr6 is not due to the exciton or defect-induced emission in Cs4PbBr6 but rather the result of exciton emission from CsPbBr3 inclusions trapped in Cs4PbBr6. [ABSTRACT FROM AUTHOR]

Luminescence concentration quenching, mainly due to a cross relaxation (CR) process between lanthanide ions (Ln3+), widely occurs in Ln3+ doped luminescent materials, setting a limit in the dopant content of Ln3+ emitters to withhold the brightness. Here, we introduced Na+ ions into the CaF2 host lattice codoped with Nd3+ emitters that alleviates concentration quenching greatly. And we show that the optimal dopant concentration of Nd3+ in colloidal CaF2:Nd nanoparticles increased from 10 to 30 mol%, resulting in an ∼32 times near-infrared (NIR) (1052 nm) brightness under 800 nm laser irradiation. Our mechanistic investigation suggests that the enhancement of NIR photo-luminescence (PL) could be attributed to not only the increasing crystallinity of nanoparticles but also the reducing concentration quenching of Nd3+ by improving the dopant distribution of Nd3+ ions in the CaF2 lattice, as evidenced by the high angle annular dark field images. These result in the optimal concentration increase to produce brightness enhancement greatly. This strategy can be utilized for other Ln3+ doped CaF2 based nanomaterials for bio-imaging. [ABSTRACT FROM AUTHOR]

Multi-dimensional accurate response and smooth signal transmission are critical challenges in the advancement of multi-resolution recognition and complex environment analysis. Inspired by the structure–activity relationship between discrepant microstructures of the spiral and radial threads in a spider web, we designed and printed graphene with porous and densely-packed microstructures to integrate into a multi-resolution graphene tactile sensor. The three-dimensional (3D) porous graphene structure performs multi-dimensional deformation responses. The laminar densely-packed graphene structure contributes excellent conductivity with flexible stability. The spider-web inspired printed pattern inherits orientational and locational kinesis tracking. The multi-structure construction with homo-graphene material can integrate discrepant electronic properties with remarkable flexibility, which will attract enormous attention for electronic skin, wearable devices and human–machine interactions. [ABSTRACT FROM AUTHOR]

Hierarchical nanosheet-based Bi2MoO6 microboxes are synthesized by a facile template-assisted strategy. MnCO3 microcubes are prepared as templates for the growth of Bi2MoO6 nanosheets and then etched by using HCl aqueous solution. In particular, the hierarchical Bi2MoO6 microboxes provide a large surface area, and facilitate visible-light absorption and charge separation, demonstrating efficient photocatalytic performance. This work highlights a new method to prepare hollow nanosheet-built Bi2MoO6 structures with high photocatalytic properties. [ABSTRACT FROM AUTHOR]

A simple, enzyme-free supersandwich-type biosensor is fabricated for the ultrasensitive detection of microRNAs (miRNAs) using N-doped graphene/Au nanoparticles (NG–AuNPs) and hemin/G-quadruplexes. In the proposed strategy, AuNPs are deposited on the surface of a MoSe2 modified electrode to immobilize the thiol-modified hairpin probe through the strong Au–S bond. When the target miRNA is added, capture DNA hybridizes with it and unfolds its stem-and-loop structure. The NG–AuNP hybrids are the main amplification element and are modified by hybridization with assistance DNA and the terminus of capture DNA, resulting in the formation of the supersandwich structure. The assistance DNA is embedded into the hemin/G-quadruplex complexes in the presence of hemin and K+ to provide an exceptional current signal for the detection of miRNAs. Under the optimized experimental conditions, a detection limit of 0.17 fM is obtained with a linear range of 10 fM–1 nM. In addition, the present biosensor shows outstanding selectivity towards mismatched miRNAs. This biosensor platform successfully realized the combination of the signal amplification technique with the supersandwich structure, providing a promising approach for the detection of miRNA-21 in practical applications. [ABSTRACT FROM AUTHOR]

Organosulfur compounds are cheap and abundant cathode materials that can offer high specific energies. Herein, we explore for the first time, the common vulcanization accelerators viz. thiuram polysulfides embedded in carbon nanotubes as binder-free cathodes in lithium batteries that show 3 highly reversible redox reactions (3 discharge plateaus) and high material utilization (up to 97%). We use electrochemical characterization techniques, first-principles calculations, XPS, XRD, FTIR, and SEM to gain insight into the chemical transformations occurring during battery cycling. We identify that the mesomeric form of lithium pentamethylene dithiocarbamate with a positive nitrogen center, formed in the discharge, can act as polysulfide and sulfide anchors through strong coulombic interactions thus enabling a capacity retention of 87% after 100 cycles at C/5 rate. A high loading cathode with an areal capacity of 5.3 mA h cm−2 tested under a low electrolyte to active material ratio of 3 μL mg−1 yields an active material specific energy of 1156 W h kg−1 thus demonstrating the potential of this class of compounds in high specific energy lithium batteries. [ABSTRACT FROM AUTHOR]

Milk fat globule-EGF factor 8 (MFG-E8) protein can promote growth factor induced survival and proliferation of vascular endothelial cells, leading to angiogenesis. Little has been reported on the potential effects of MFG-E8 on cell differentiation and the molecular mechanism. In this study, MFG-E8, the major component of milk fat globule membrane (MFGM) protein (82.35%), was isolated and purified using cellulose DEAE-52. Its effects on myogenic differentiation of murine skeletal muscle C2C12 cells were investigated using qRT-PCR, Western blotting and immunofluorescence assay. MFG-E8 promoted the formation of multinucleated myotubes, and increased the fusion index. In addition, Akt-activity was significantly increased during MFG-E8 induced C2C12 cell differentiation, whereas wortmannin, a PI3K inhibitor, was able to block the differentiation of C2C12 cells promoted by MFG-E8. MFG-E8 enhanced the expression of the myogenic regulatory factor MyHC in C2C12 cells over time. Conversely, the expression of MyHC was also inhibited by wortmannin. We conclude that MFG-E8 promotes the differentiation of C2C12 cells by activating the PI3K/Akt signaling pathway. Taken together, these results show that MFG-E8 could exert a beneficial effect on C2C12 myoblast cell differentiation, and therefore, it may have potential as a differentiation-inducing agent for the therapy of sarcopenia. [ABSTRACT FROM AUTHOR]

A novel method to improve the proliferation activity of C2C12 cells by the bovine milk fat globule membrane (MFGM) protein was established in this study. The MFGM protein was extracted and isolated into 4 fractions using an electric cream separator, and purified by a cellulose DEAE-52 column. Fraction 2 accounted for 57.8% of the total MFGM protein, and was used in the following study. The MTT assay showed that it induced cell proliferation activity, increased the cell survival rate and the cell number using flow cytometry and fluorescence microscopy analysis. There were only subtle changes in the morphology as observed using confocal scanning laser microscopy, but the number of mitochondria was significantly increased as observed using transmission electron microscopy analysis. Furthermore, the mRNA expression of MyoD, cyclin D1, p70S6K and mTOR was up-regulated as determined utilizing the quantitative real-time PCR assay, and the activation of Akt and mTOR phosphorylation was up regulated as determined using the Western blot assay. The main protein in fraction 2, assayed by 1-D gel electrophoresis and MALDI TOF-TOF, was identified as milk fat globule-EGF factor 8, the content was 65.6% of the total protein in fraction 2. The results elucidate a new molecular mechanism of the MFGM protein fraction 2: the activation of the Akt signal pathway in promoting cell proliferation. [ABSTRACT FROM AUTHOR]

Polypropylene (PP), as one of the most common prosthetic materials, has been widely used in intra-peritoneal repair. However, its adhesion to viscera has severely limited its application. Therefore it is critical to improve the PP surface with an anti-adhesion property. In this work, based on dopamine-inspired chemistry, virgin PP (V-PP) mesh was first pretreated with O2 plasma, subsequently dipped in dopamine aqueous solution for 24 h, and then chitosan (CS) was grafted onto it. Finally the anti-adhesion mesh (O-PP/PDA/CS) was obtained. The formation procedure of a PDA/CS ad-layer was characterized by water contact angle measurements, ATR-FTIR, SEM, and XPS. The results show that a PDA/CS ad-layer could be coated on the PP surface efficiently. NIH/3T3 cells were first cultured on O-PP/PDA/CS meshes to evaluate the availability of anti-adhesion and biocompatibility in vitro, and then the efficacy of the PDA/CS-coating as a barrier for reducing postsurgical adhesions was evaluated using a rat abdominal wall defect model. Compared with the V-PP group, NIH/3T3 cells exhibited higher viability in the O-PP/PDA/CS groups as evaluated by the CCK-8 method. In addition, NIH/3T3 cells grow into round-shapes on the O-PP/PDA/CS surface. This indicates that the modification strategy can facilely lead to excellent properties of anti-adhesion. In vivo tests further indicate that O-PP/PDA/CS meshes were effective in reducing adhesion formation. [ABSTRACT FROM AUTHOR]

Rapid development of wearable electronic devices stimulates the demand for matched energy storage devices. Such a complex application requires electronic devices and their power units to possess mechanically deformable ability and even healing capability to accommodate large scale mechanical deformation and self-heal cracks or fractures. Supercapacitors (SCs) are regarded as promising power units for wearable electronic devices due to the advantages of high power density, rapid charge rate, ultra-long life, great stability and safety. But conventional rigid SCs or primarily flexible SCs (bendable or twistable) are far from the requirements of practical applications of wearable electronic devices. SMART SCs with intensively deformable or healable abilities have been developed to satisfy these rigorous demands and have become a hot topic recently. In this article, we introduce the recent progress in this booming research area of compressible, self-healable, and shape memory SCs. For each type of these SMART SCs, the device or electrode structure design, the functional materials and their working mechanism, and the employed electrolyte are discussed in detail. Moreover, we also outline the challenges and perspective for the development of advanced SMART SCs. Both the mechanical and electrochemical performance of the SMART SCs require improvement. Meanwhile, it will be a fascinating trend to integrate multiple mechanical and non-mechanical functions into SMART SCs to make them novel self-powered multi-functional units in the near future. [ABSTRACT FROM AUTHOR]