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As a newly emerging pathogen, Candida auris has spread rapidly and caused a serious invasive infection. Candida auris often appeared high resistance to classical antifungal drugs. Drug combination therapy is emerging as an effective and well-established strategy to relieve drug resistance problems. The objective of present work was to examine the activity of fluconazole in combination with chlorhexidine acetate against Candida auris isolates.Antiplanktonic activity was studied using the EUCAST methodology and growth curve assay. Antibiofilm effectiveness was determined by the crystal violet method, checkerboard microdilution assay, scanning electron microscopy, and confocal laser scanning microscopy.The results indicated that the 80% minimal inhibitory concentrations for fluconazole alone against Candida auris were 2-32 mg/L and for chlorhexidine acetate were 2-8 mg/L. The combination of fluconazole with chlorhexidine acetate exhibited synergism with the growth curve assay. In addition, the checkerboard microdilution assay presented that fluconazole was strongly synergistic with chlorhexidine acetate (sFICI0.1875) in inhibiting the growth of Candida auris biofilms. The scanning electron microscopy and confocal laser scanning microscopy further exhibited the alteration of morphology of the cells and architecture of the biofilms.The combination therapy of fluconazole and chlorhexidine acetate provides a new potential strategy for the treatment of clinical Candida auris infection.

Background Growth factors execute essential biological functions and affect various physiological and pathological processes, including peripheral nerve repair and regeneration. Our previous sequencing data showed that the mRNA coding for betacellulin (Btc), an epidermal growth factor protein family member, was up-regulated in rat sciatic nerve segment after nerve injury, implying the potential involvement of Btc during peripheral nerve regeneration. Methods Expression of Btc was examined in Schwann cells by immunostaining. The function of Btc in regulating Schwann cells was investigated by transfecting cultured cells with siRNA segment against Btc or treating cells with Btc recombinant protein. The influence of Schwann cell-secreted Btc on neurons was determined using a co-culture assay. The in vivo effects of Btc on Schwann cell migration and axon elongation after rat sciatic nerve injury were further evaluated. Results Immunostaining images and ELISA outcomes indicated that Btc was present in and secreted by Schwann cells. Transwell migration and wound healing observations showed that transfection with siRNA against Btc impeded Schwann cell migration while application of exogenous Btc advanced Schwann cell migration. Besides the regulating effect on Schwann cell phenotype, Btc secreted by Schwann cells influenced neuron behavior and increased neurite length. In vivo evidence supported the promoting role of Btc in nerve regeneration after both rat sciatic nerve crush injury and transection injury. Conclusion Our findings demonstrate the essential roles of Btc on Schwann cell migration and axon elongation and imply the potential application of Btc as a regenerative strategy for treating peripheral nerve injury.

Cisplatin (DDP) is a commonly used chemotherapy drug, but DDP can cause skeletal muscle atrophy and cachexia. This study combined the DDP-induced C2C12 myotube atrophy model and the LLC tumour-bearing mouse cachexia model under DDP treatment to explore the effect and mechanism of naringenin (NAR) in alleviating skeletal muscle atrophy and cachexia. NAR alleviated the decreases in body weight, food intake, muscle, adipose tissue and kidney weight and forelimb grip strength in LLC tumour-bearing mice under DDP treatment and reduced the serum level of TNF-α. High dose NAR also enhanced the antitumour effect of DDP. NAR can prevent the cross-sectional area reduction of skeletal muscle fibres and prevent the change in fibre type ratio induced by DDP. NAR intervention inhibits the RIPK1/AMPK/NF-κB pathway in skeletal muscle, downregulates the expression of Atrogin1 and MuRF1, and inhibits the degradation of skeletal muscle protein. In C2C12 myotubes treated with DDP, NAR inhibited the RIPK1/AMPK/NF-κB pathway to reduce myotube cell atrophy, and the overexpression of RIPK1 reversed the therapeutic effect of NAR. These results indicate that NAR downregulates the expression of Atrogin1 and MuRF1 by regulating the RIPK1/AMPK/NF-κB pathway and alleviates DDP-induced skeletal muscle atrophy.

Unusual interactions occur between phonons and electrons in the topological semimetal tungsten diphosphide, a finding that could explain some of the material's strange properties.

A novel and efficient route is proposed to fabricate Fe3O4/polypyrrole (Fe3O4/PPy) nanotubes via a one-pot process. The one-pot strategy involves the synthesis of Fe3O4/PPy nanotubes by oxidative polymerization of pyrrole (Py) monomer using Fe3+ as an oxidant in the presence of methyl orange (MO) and Fe3+ used as iron source to form Fe3O4 simultaneously in basic conditions without adding any additional iron source and oxidant. The effects of Fe3+ concentration on the morphology and adsorption capacity of the Fe3O4/PPy nanotubes were investigated. The Fe3O4/PPy nanotubes exhibit a tubular structure. Fe3O4 nanoparticles are well dispersed among the PPy nanotubes. The Fe3O4/PPy nanotubes exhibit excellent magnetic property, which make them easy to separate from wastewater by magnetic separation. The diameter of the PPy nanotubes decreased with the increase of the Fe3+ concentration. The Fe3O4/PPy nanotubes showed strong adsorption capability for Cr(VI) with the maximum adsorption capacity of about 451.45 mg·g−1, which is significantly higher than bare Fe3O4 nanoparticles. Cr(VI) was adsorbed on Fe3O4/PPy nanotubes by ion exchange and chelation, where Cr(VI) was partially reduced to Cr(III) due to the existence of −NH+ on the Fe3O4/PPy nanotubes. Furthermore, the Fe3O4/PPy nanotubes are recyclable, retaining 90% of the initial removal efficiency after 5 adsorption/desorption cycles.

Hierarchically porous (HP) design provides an effective alternative to develop lightweight thermal insulation (T-I) materials, which play an important role in efficient energy management. Unlike elaborate synthetic methods, achieving HP features via supercritical fluid (SCF) techniques is still at an early stage. In this study, a facile and effective approach is reported to develop tailored HP foams via SCF foaming of binary blends with nanoscale phase separation patterns. The resultant cyclic olefin copolymer (COC) blend foams are extremely lightweight (50 kg m−3) and have excellent thermal conductivity of 25.8 mW m-1K−1, which is on par with the thermal conductivity of air. Through the SCF foaming process, tunable HP structures can be created from COC blends with nanoscale phase patterns (phase size from ∼ 150 to 240 nm). Different from traditional T-I polystyrene foams, chemical resistant COC blend foams are good candidates for durable coatings, and a dual-mode thermal device was successfully assembled with active photothermal conversion functionality and passive T-I performance, which exhibited a temperature difference of 32 °C between the two surfaces under illumination (2.4 × 105 lx). This opens up a new perspective for the development of lightweight, chemically resistant and highly thermally insulating foams for thermal management applications.

BackgroundVasomotor regulation of dermal blood vessels, which are critical in the function of the skin in thermoregulatory control, involves both neural and non-neural mechanisms. Whereas the role of sympathetic nerves in regulating vasomotor activities is comprehensively studied and well recognized, that of sensory nerves is underappreciated. Studies in rodents have shown that severance of the sciatic nerve leads to vasodilatation in the foot, but whether sympathetic or sensory nerve fibers or both are responsible for the neurogenic vasodilatation remains unknown.ResultsIn adult Sprague–Dawley rats, vasodilatation after transection of the sciatic nerve gradually diminished to normal within 3–4 days. The neurotmesis-induced neurogenic vasodilatation was not detectable when the sciatic nerve was chronically deafferentated by selective resection of the dorsal root ganglia (DRGs) that supply the nerve. Specific activation of C-afferents by intra-neural injection of capsaicin resulted in neurogenic vasodilatation to a magnitude comparable to that by neurotmesis, and transection of the sciatic nerve pre-injected with capsaicin did not induce further vasodilatation.ConclusionsOur results collectively indicate that vasodilatation after traumatic nerve injury in rats is predominantly mediated by C-fiber afferents.

The recent discovery that specific materials can simultaneously exhibit n-type conduction and p-type conduction along different directions of the single crystal has the potential to impact a broad range of electronic and energy-harvesting technologies. Here, we establish the chemical design principles for creating materials with this behavior. First, we define the single-carrier and multicarrier mechanisms for axis-dependent conduction polarity and their identifying band structure fingerprints. We show using first-principles predictions that the AMX (A = Ca, Sr, Ba; M = Cu, Ag, Au; X = P, As, Sb) compounds consisting of MX honeycomb layers separated by A cations can exhibit p-type conduction in-plane and n-type conduction cross-plane via either mechanism depending on the doping level. We build up the band structure of BaCuAs using a molecular orbital approach to illustrate the structural origins of the two different mechanisms for axis-dependent conduction polarity. In total, this work shows this phenomenon can be quite prevalent in layered materials and reveals how to identify prospective materials.

The graphane analogues of group 14 are a unique family of 2D materials due to the necessity of a terminal ligand for stability. Here we highlight how changing the surface ligand can lead to nonobvious interactions with other chemical species. We show using XRD, FTIR, and TGA that GeCH3 reversibly absorbs water into the van der Waals space, whereas GeH does not intercalate water. Molecular dynamics and density functional theory simulations predict that water datively interacts with the Ge-C ?* pocket on the Ge framework, resulting in local structural distortions. Surprisingly, these distortions give rise to an intense above band gap luminescence state of 1.87 eV, with an average lifetime of hundreds of picoseconds. This work opens potential applications for exploiting surface functionalization chemistry of 2D materials to create membrane and separation technologies.

Metabolic alterations are increasingly recognized as important novel anti-cancer targets. Among several regulators of metabolic alterations, fructose 2,6 bisphosphate (F2,6BP) is a critical glycolytic regulator. Inhibition of the active form of PFKFB3ser461 using a novel inhibitor, PFK158 resulted in reduced glucose uptake, ATP production, lactate release as well as induction of apoptosis in gynecologic cancer cells. Moreover, we found that PFK158 synergizes with carboplatin (CBPt) and paclitaxel (PTX) in the chemoresistant cell lines, C13 and HeyA8MDR but not in their chemosensitive counterparts, OV2008 and HeyA8, respectively. We determined that PFK158-induced autophagic flux leads to lipophagy resulting in the downregulation of cPLA2, a lipid droplet (LD) associated protein. Immunofluorescence and co-immunoprecipitation revealed colocalization of p62/SQSTM1 with cPLA2 in HeyA8MDR cells uncovering a novel pathway for the breakdown of LDs promoted by PFK158. Interestingly, treating the cells with the autophagic inhibitor bafilomycin A reversed the PFK158-mediated synergy and lipophagy in chemoresistant cells. Finally, in a highly metastatic PTX-resistant in vivo ovarian mouse model, a combination of PFK158 with CBPt significantly reduced tumor weight and ascites and reduced LDs in tumor tissue as seen by immunofluorescence and transmission electron microscopy compared to untreated mice. Since the majority of cancer patients will eventually recur and develop chemoresistance, our results suggest that PFK158 in combination with standard chemotherapy may have a direct clinical role in the treatment of recurrent cancer.

High-impact polypropylene (HIPP) is a commercially important polymer alloy with complex morphological structure. In this contribution, two commercial HIPPs have been investigated in detail by atomic force microscopy-infrared in conjunction with local thermal analysis to determine the composition and structure of the nanodomains. Both alloys contain numerous core-shell rubber particles dispersed in polypropylene matrix. In HIPP-1, the rigid cores of the particles are rich in polypropylene, which is highly crystalline, whereas for HIPP-2, the major component of the rigid cores is polyethylene with a high degree of crystallinity. The formation of these very different structures and compositions in the core and rubber domains may be attributed to different chain structures and compositions of the copolymers in the alloys produced by different catalysts.

Polytypism, or the ability for materials to crystallize with different stacking sequences, often leads to fundamentally different properties in families of two-dimensional materials. Here, we show that is possible to control the polytype of GeH, a representative two-dimensional material that is synthesized topotactically by first controlling the polytype sequence of the precursor Zintl phase. 1T, 2H, and 6R GeH can be prepared by the topotactic deintercalation of 1T EuGe2, 2H α-CaGe2, and 6R β-CaGe2, respectively. The 6R and 1T GeH polytypes exhibit remarkably similar properties and feature band gaps of 1.63 and 1.59 eV, respectively. However, the 2H CaGe2 precursor forms due to the incorporation of small amounts of In flux in the germanium lattice, which is retained when converted to GeH. Consequently, 2H GeH has a reduced band gap of 1.45 eV. Finally, temperature dependent diffraction of 6R GeH shows a negative coefficient of thermal expansion along the a-axis and a positive coefficient of thermal expan...

Introduction of the dynamic bonds will endow the polymer architectures with attractive adaptive properties, which enable thermoset materials re-processable, recyclable and sustainable. However, exploration of the miscible and cost-effective moieties containing such dynamic fragments are the burning question to implement the reversible polymer on a mass basis. Here we report an indirect formation strategy of borate ester crosslinkage from commercially available feedstocks . Remarkably, the borate ester crosslinks are ingeniously generated from borate and diols which are formed in-situ by glycidol and amines. The good miscibility of the precursors could be achieved without the use of any solvent, which benefits the large-scale production and practical application of these promising adaptive thermoset polymers. Such thermadapt epoxy networks utilizing dynamic borate ester crosslinking exhibit adaptive properties such as reprocessing, welding, self-healing, and extrusion injection molding . In addition, the facile reprocess and remold processes of resulted carbon fiber composite are demonstrated by incorporating thermadapt epoxy resin with continuous carbon fiber sheets. Our synthetic strategy provides innovative insights as a green and sustainable solution to traditional thermosets and its composites.

Increasing the intrinsic regeneration potential of neurons is the key to promote axon regeneration and repair of nerve injury. Therefore, identifying the molecular switches that respond to nerve injury may play critical role in improving intrinsic regeneration ability. The mechanisms by which injury unlocks the intrinsic axonal growth competence of mature neurons are not well understood. The present study identified the key regulatory genes after sciatic nerve crush injury by RNA sequencing (RNA-Seq) and found that the hub gene Vav1 was highly expressed at both early response and regenerative stages of sciatic nerve injury. Furthermore, Vav1 was required for axon regeneration of dorsal root ganglia (DRG) neurons and functional recovery. Kruppel-like factor 2 (Klf2) was induced by retrograde Ca2+ signaling from injured axons and could directly promote Vav1 transcription in adult DRG neurons. The increased Vav1 then promoted axon regeneration by activating Rac1 GTPase independent of its tyrosine phosphorylation. Collectively, these findings break through previous limited cognition of Vav1, and first reveal a crucial role of Vav1 as a molecular switch in response to axonal injury for promoting axon regeneration, which might further serve as a novel molecular therapeutic target for clinical nerve injury repair.

Tract tracing with neuronal tracers not only represents a straightforward approach to identify axonal projection connection between regions of the nervous system at distance but also provides compelling evidence for axonal regeneration. An ideal neuronal tracer meets certain criteria including high labeling efficacy, minimal neurotoxicity, rapid labeling, suitable stability in vivo, and compatibility to tissue processing for histological/immunohistochemical staining. Although labeling efficacy of commonly used fluorescent tracers has been studied extensively, neurotoxicity and their effect on neural functions remains poorly understood. In the present study, we comprehensively evaluated motor and sensory nerve function 2–24 weeks after injection of retrograde tracer Fluoro-Gold (FG), True Blue (TB) or Fluoro-Ruby (FR) in the tibial nerve in adult Spague-Dawley rats. We found that motor and sensory nerve functions were completely recovered by 24 weeks after tracer exposure, and that FG lead to a more prolonged delay in functional recovery than TB. These findings shed light on the long-term effect of tracers on nerve function and peripheral axonal regeneration, and therefore have implications in selection of appropriate tracers in relevant studies.

The presence of a point defect typically breaks the stoichiometry in a semiconductor. For example, a vacancy on an A-site in an AB compound makes the crystal B-rich. As the stoichiometry changes, so do the chemical potentials. While the prevalent first-principles methods have provided significant insight into characters of point defects in a transparent manner, the crucial connection between crystal stoichiometry and chemical potentials is usually not made. However, ad hoc choices for chemical potentials can lead to nonphysical negative formation energies in some Fermi level ranges, along with questions about charge balance. Herein, we formulate a canonical framework describing how the chemical potential of each element is directly linked to the composition of the crystal under (off-)stoichiometric conditions instead of the ad hoc assumption that the chemical potential is the elemental limit under a certain growth condition. Consequently, the chemical potential changes with the Fermi level within the band gap, and the formation energies are positive. Using such an approach, we present $ab$ $initio$ results for native point defects in BAs, a semiconductor with ultra-high room temperature thermal conductivity. We find that antisites are the constitutional defects in off-stoichiometric material, while B$_\mathrm{As}$ antisites and B vacancies dominate in the stoichiometric material. We further discuss the thermodynamic equilibrium and charge neutrality point in BAs in light of our stoichiometry-determined chemical potentials. As discussed, our work offers a more applicable and accessible approach to tackle defect formation energies in semiconductors, especially the ones with wide gap where negative formation energies are commonly seen., Comment: Including both main text and supplemental material

In the effort to alleviate climate change and energy consumption issues, thermally insulating polymeric foams can improve energy-management efficiency. To limit the transmission of infrared (IR) radiation through such foams, strong IR-shielding carbon particles are often incorporated to improve thermal insulation performance by blocking IR radiation. However, carbon particles can also dramatically increase solid phase conduction, which counteract efforts to further decrease thermal conductivity. Herein, we report a superior thermal insulation (~28.5 mW·m−1K−1) microcellular foam from ethylene-norbornene (NB) based cyclic olefin copolymers (COCs). Unlike the traditional carbon-filled approach, the incorporation of more NB segments (content from 33, 36, 51 and 58 mol %) in the COC structure greatly improved its ability to block thermal radiation without increasing its solid thermal conductivity. Using the supercritical CO2 and n-butane as physical blowing agents, we fabricated COC foams with tunable morphology. The void fraction of the foams ranged from 50 to 92%, and they demonstrated a high degree of closed cell content (>98%). In COC foams with given cellular structures (e.g. void fraction of 90%, cell size of 100–200 μm and cell density of ~107 cells/cc), their total thermal conductivity decreases from 49.6 to 37.9 mW·m−1K−1 with increasing NB content from 33 to 58%, which is attributed to high-NB COC’s strong ability to attenuate thermal radiation. Subsequently, a highly expanded COC microcellular foam with superior thermal conductivity was successfully developed by tuning both NB content and cellular structure. As a proof of concept, the incorporation of NB segments in COC foams can offer an effective way to shield thermal radiation, opening a new perspective in the development of thermal insulation foams.

The sulfide capacities of CaO-MgO-Al2O3-SiO2-CrO x slags were measured by gas–slag equilibration method in the temperature range of 1823 K to 1898 K (1550 °C to 1625 °C) to reveal the effect of CrO x on the sulfide capacities of slags. Both higher basicity and temperature enhanced sulfide capacities. The CrO x additions in the range of 0 to 5 mass pct increased the sulfide capacity, but, further increase of CrO x contents to 7 pct was found to lower the sulfide capacity. Utilizing the relationship for estimating the ratio of Cr(II)/Cr(III) put forward by the present authors, the influence of Cr(II) on the sulfide capacities of the slags studied is discussed.

Electrical conductivity of molten slags is one of the most important physicochemical properties and it also has a close relationship to the structure of slag. This article focused on the basic slag system CaO-MgO-Al2O3-SiO2 and made estimations for electrical conductivity. Ion-oxygen parameter was selected to describe the relationship between electrical conductivity with compositions. Moreover, the interaction between composition and temperature was embodied in the final model formula. It was shown that increasing CaO and MgO contents enhanced the ability for electric conduction. Moreover, with a higher temperature, the change of electrical conductivity with ion-oxygen parameter was more remarkable. This model gives reasonable prediction of the electrical conductivity for the slags studied with the mean deviation of 14.3%. Thus, this model would provide a feasible tool for industry to predict and optimize the electrical conductivity of slag system.

Tight junctions seal off physical barriers, regulate fluid and solute flow, and protect the endoneurial microenvironment of the peripheral nervous system. Physical barriers in the peripheral nervous system were disrupted after nerve injury. However, the dynamic changes of tight junction components after peripheral nerve injury have not been fully determined yet. In the current study, by using previously obtained deep sequencing outcomes and bioinformatic tools, we found that tight junction signaling pathway was activated after peripheral nerve injury. The investigation of the temporal expression patterns of components in tight junction signaling pathway suggested that many claudin family members were down-regulated after nerve injury. Moreover, we examined the effects of matrix metalloproteinases 7 and 9 (MMP7 and MMP9) on tight junction genes both in vitro and in vivo and found that MMP7 and MMP9 modulated the expressions of genes coding for claudin 1, claudin 10, and claudin 22. Our study revealed the dynamic changes of tight junction components after peripheral nerve injury and thus might contribute to the understanding of the molecular mechanisms underlying peripheral nerve injury and regeneration.

As a 2D ferromagnetic semiconductor with magnetic ordering, atomically thin chromium triiodide is the latest addition to the family of two-dimensional (2D) materials. However, realistic exploration of CrI3-based devices and heterostructures is challenging, due to its extreme instability under ambient conditions. Here we present Raman characterization of CrI3, and demonstrate that the main degradation pathway of CrI3 is the photocatalytic substitution of iodine by water. While simple encapsulation by Al2O3, PMMA and hexagonal BN (hBN) only leads to modest reduction in degradation rate, minimizing exposure of light markedly improves stability, and CrI3 sheets sandwiched between hBN layers are air-stable for >10 days. By monitoring the transfer characteristics of CrI3/graphene heterostructure over the course of degradation, we show that the aquachromium solution hole-dopes graphene., 4 figures

Actin cytoskeleton regulates many essential biological functions, including cellular development, shape, polarity, and motility. The organization of actin cytoskeleton has also been associated with numerous physiological and pathological conditions, for instance, the elongation of axonal growth cone during peripheral nerve regeneration. However, the spatio-temporal expression patterns of actin cytoskeleton-related genes and the specific roles of actin cytoskeleton following peripheral nerve injury have not been fully revealed. To address this question, we made rat sciatic nerve crush surgery, collected injured sciatic nerve stumps, analyzed RNA deep sequencing outcomes, and specifically studied two significantly involved canonical pathways that were related with actin, actin cytoskeleton signaling and regulation of actin-based motility by Rho. By using bioinformatic tools and qRT-PCR, We identified and validated differentially expressed genes in these two signaling pathways. Moreover, by applying actin polymerization inhibitor cytochalasin D to sciatic nerve crushed rats, we studied the in vivo effect of cytochalasin D and demonstrated that inhibiting actin polymerization would delay the migration of Schwann cells and hinder the repair and regeneration of injured peripheral nerves. Overall, our data revealed the changes of actin cytoskeleton-related genes following peripheral nerve injury and stated the importance of actin cytoskeleton during peripheral nerve regeneration.

The graphene and silk fibroin based carbon (GCN-S) material is prepared by the carbonization of reduced graphene oxide (RGO) and silk fibroin (SF) nanofibrils composite in the presence of KOH. The good combination of RGO and SF nanofibrils, which turns out to be micro/meso-carbon after activation, endows the obtained GCN-S materials with high specific surface area, multi-porous structure, good electrical conductivity, and consequently excellent electrochemical performance. For example, the GCN-S-0.5 synthesized at 0.5 : 1 ratio of KOH and RGO/SF nanofibrils suspension shows a high BET specific surface area of 3.2 × 103 m2 g−1, and the specific capacitance is 256 F g−1 at a current density of 0.5 A g−1. Moreover, it still delivers a specific capacitance of 188 F g−1 even at a current density as high as 50 A g−1, corresponding to a capacitance retention rate of 73.4%. After a charge–discharge rate of 5 A g−1 for 10 000 cycles, the GCN-S-0.5 exhibits remarkable electrochemical stability with the capacitance retention ratio of 96.3%. Furthermore, the GCN-S-0.5 based supercapacitor achieves high energy density up to 14.4 Wh kg−1 at an ultrahigh power density of 40 000 W kg−1. The results shown in this work indicate that our GCN-S material is a promising candidate for manufacturing supercapacitors with both a high performance and relatively low cost.

In order to optimize the current reduction process of chromite, a good knowledge of reduction mechanism involved is required. The basic component in chromite ore is FeCr2O4 with gangue component like MgO and Al2O3. In lack of clear and consistent explanation about the effect of addition on the reduction of FeCr2O4, investigation of synthetic FeCr2O4 with different kind and amount of additions was carried out at 1673K under isothermal mode. Kinetic mechanism was also studied by linear fitting of different kinetic equations. Combined with rate-controlling step, it could be concluded as follows. CaO could enhance the reduction because Ca2+ would replace Fe2+, thus facilitated the ion diffusion in solid phase. Al2O3 had a positive influence as well, since Al3+ could form a solid solution phase with Cr3+ and made Cr3+ reduced more easily. MgO would hinder the reduction due to formation of a more stable phase MgCr2O4. SiO2 would also hamper the Cr metallization because there was a liquid phase formed when Cr3+ was reduced to divalent, which would impede the nucleation of reduction product.

Extracellular/acellular matrix has been attracted much research interests for its unique biological characteristics, and ACM modified neural scaffolds shows the remarkable role of promoting peripheral nerve regeneration. In this study, skin-derived precursors pre-differentiated into Schwann cells (SKP-SCs) were used as parent cells to generate acellular(ACM) for constructing a ACM-modified neural scaffold. SKP-SCs were co-cultured with chitosan nerve guidance conduits (NGC) and silk fibroin filamentous fillers, followed by decellularization to stimulate ACM deposition. This NGC-based, SKP-SC-derived ACM-modified neural scaffold was used for bridging a 10 mm long rat sciatic nerve gap. Histological and functional evaluation after grafting demonstrated that regenerative outcomes achieved by this engineered neural scaffold were better than those achieved by a plain chitosan-silk fibroin scaffold, and suggested the benefits of SKP-SC-derived ACM for peripheral nerve repair.

Theoretical studies and experimental implementations of quantum correlation are the important contents of continuous variables quantum optics and quantum information science. There are various systems for the study of quantum correlation. Here, we study an experimental scheme for generating three quantum correlated beams based on phase-sensitive cascaded four-wave-mixing (FWM) processes in rubidium vapor. Quantum correlation including intensity difference or sum squeezing, two other combinatorial squeezing, and quantum entanglement among the three output light fields are theoretically analyzed in this paper. Also, the comparison of the quantum correlations have been made between the phase-sensitive cascaded FWM processes and the phase-insensitive cascaded FWM processes. By changing the phases and intensities of the input beams, it is interesting to find that the maximum degrees of various combinatorial squeezing are equal when the two FWM processes share a common intensity gain. When the common intensity gain of the two FWM processes changes, the maximum degrees of different combinatorial squeezing will be synchronously controlled. At last we discuss the genuine tripartite entanglement and steering in our phase-sensitive cascaded scheme, and compare them with the cases of the phase-insensitive cascaded scheme.

We use a combination of optical and electrostatic surface science techniques to measure electronically active native defects in multilayer GeCH3 and GeH, two-dimensional (2D) functionalized materials. Chemical processing techniques coupled with density functional theory enable us to identify the specific physical nature of both native point defects and synthesis-related impurities which can limit the optical and charge transport properties of these materials. Direct comparison of optical measurements with calculated electronic levels provides identification of these localized, deep level gap states and confirms partial H-passivation of dangling bonds, revealing synthesis and processing methods needed to control specific defects and optimize these 2D materials for emergent solid state-electronics.We use a combination of optical and electrostatic surface science techniques to measure electronically active native defects in multilayer GeCH3 and GeH, two-dimensional (2D) functionalized materials. Chemical processing techniques coupled with density functional theory enable us to identify the specific physical nature of both native point defects and synthesis-related impurities which can limit the optical and charge transport properties of these materials. Direct comparison of optical measurements with calculated electronic levels provides identification of these localized, deep level gap states and confirms partial H-passivation of dangling bonds, revealing synthesis and processing methods needed to control specific defects and optimize these 2D materials for emergent solid state-electronics.

Jia Jiang,1,2 Fang Wan,1 Jianjun Yang,1 Wei Hao,3 Yaxian Wang,3 Jinrong Yao,3 Zhengzhong Shao,3 Peng Zhang,1 Jun Chen,1 Liang Zhou,4 Shiyi Chen11Fudan University Sports Medicine Center and Department of Sports Medicine and Arthroscopy Surgery, Huashan Hospital, 2State Key Laboratory of Molecular Engineering of Polymers, 3Laboratory of Advanced Materials, National Key Laboratory ofMolecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai, People’s Republic of China; 4Department of Forest Products, Anhui Agricultural University, Hefei Anhui Province, People’s Republic ofChinaBackground: Application of artificial ligament in anterior cruciate ligament reconstruction is one of the research focuses of sports medicine but the biological tendon–bone healing still remains a problem. The preliminary study of hydroxyapatite (HAP) coating on the polyethylene terephthalate (PET) surface could effectively induce the osteoblast differentiation, but the tendon–bone healing was still not stable. As a green synthesis process, the biomimetic mineralization can simulate the natural bone growth in vitro and in vivo.Methods: HAP crystals were grown under the guide of silk fibroin (SF) PET surface by biomimetic route. Several techniques including scanning electron microscopy, attenuated total reflectance Fourier transform infrared spectroscopy, X-ray diffraction, and energy-dispersive X-ray spectroscopy were utilized for proving the introduction of both SF and HAP. The viability and osseointegration of bone marrow stromal cells on the surface of three kinds of ligament, including PET group (non-coating group), PET+SF group (SF-coating group), and PET+SF+HAP group (combined HAP- and SF-coating group), were analyzed by CCK-8 assays and alkaline phosphatase (ALP) detection. Seventy-two mature male New Zealand rabbits were randomly divided into three groups. Among them, 36 rabbits were sacrificed for mechanical testing, and histological examination for the others. Results: The SF and SF+HAP were successfully coated on the surface of PET fiber. The CCK-8 assay showed that the cell proliferation on PET+SF+HAP group was better than the other two groups from 24 to 120 hours. After 14 days of culture, the cells in the PET+SF+HAP group delivered higher levels of ALP than the other two groups. After 3 days of culture, the expression level of integrin β1 in the PET+SF+HAP group and PET+SF group were higher than in the PET group. The mean load to failure and the stiffness value of the PET+SF+HAP group were both higher than the other two groups. Hematoxylin and eosin staining showed that new bone tissue formation was only found in the PET+SF+HAP group 8 weeks postoperatively. Masson staining showed that in the PET+SF+HAP group 8 weeks postoperatively, the PET fibers were almost completely encircled by collagen. Histomorphometric analysis showed that the width of the graft–bone interface in the PET+SF+HAP group was narrower than that in the other two groups 4 and 8 weeks postoperatively. The mRNA level of BMP-7 in the PET+SF+HAP groups was significantly higher than those in the other two groups 4 and 8 weeks postoperatively.Conclusion: The study showed that the combined SF and HAP coating by biomimetic route on the surface of PET artificial ligament could induce graft osseointegration in the bone tunnel, providing theoretical and experimental foundation for manufacturing novel artificial ligaments meeting the clinical needs.Keywords: biomineralization, tendon–bone healing, ligament reconstruction

Sulfonated polyaniline (SPAN) is a self-doped conducting polymer. It has a high water solubility and a novel pH-dependent DC conductivity that is of interest for fundamental science and also for applications in such areas as rechargeable battery and pH control technologies. We report here the extensive characterization and details of synthesis of a new form of sulfonated polyaniline (LEB-SPAN) which shows novel or significantly improved chemical and physical properties. LEB-SPAN has a high sulfur to nitrogen ratio (S/N) of ∼0.75, 50% larger than that previously reported for EB-SPAN, S/N ∼0.50. This change in composition leads to significant alteration of the properties including an order of magnitude increase in the room temperature DC conductivity to ∼1 S·cm-1, nearly double the solubility in water, and a completely different pH dependence of the oxidation potential (E1/2). For LEB-SPAN the DC conductivity is unaffected by pH over the range 0 ≤ pH ≤ 14, strikingly different from the behavior of both pare...

Malignant gliomas are the most common and deadly primary brain tumors in adults. Increasing evidence has indicated that microRNAs (miRNAs) have an influence on the regulation of apoptotic cell signaling. Downregulation of miRNA 218 (miR-218) has been indicated in human glioma specimens. Here, we investigate the function of miR-218 in apoptosis and tumor growth of glioma cells.The expression of miR-218 was detected by real-time quantitative reverse transcriptase PCR. The effects of miR-218 on glioma cell proliferation and tumorigenicity were investigated by in vitro clonogenicity and in vivo xenograft assay. Apoptosis was evaluated by flow cytometric analysis and assay by terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling. The downstream targets of miR-218 were identified by bioinformatics analysis and further validated by Western blot and luciferase reporter assay.Overexpression of miR-218 induces glioma cell apoptosis and inhibits glioma cell viability, proliferation, and tumorigenicity. Epidermal growth factor receptor-coamplified and overexpressed protein (ECOP) was identified as a functional downstream target of miR-218, which can regulate transcriptional activity of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and associated with apoptotic response. Ectopic expression of ECOP rescued the glioma cells from miR-218-induced apoptosis and increased NF-κB activity.These results suggest that miR-218 sensitizes glioma cells to apoptosis by regulating ECOP-mediated suppression of NF-κB activity, which may provide novel opportunities for glioma therapy.

Angiogenesis is a key process in regenerative medicine generally, as well as in the specific field of nerve regeneration. However, no convenient and objective method for evaluating the angiogenesis of tissue-engineered nerves has been reported. In this study, tissue-engineered nerves were constructed in vitro using Schwann cells differentiated from rat skin-derived precursors as supporting cells and chitosan nerve conduits combined with silk fibroin fibers as scaffolds to bridge 10-mm sciatic nerve defects in rats. Four weeks after surgery, three-dimensional blood vessel reconstructions were made through MICROFIL perfusion and micro-CT scanning, and parameter analysis of the tissue-engineered nerves was performed. New blood vessels grew into the tissue-engineered nerves from three main directions: the proximal end, the distal end, and the middle. The parameter analysis of the three-dimensional blood vessel images yielded several parameters, including the number, diameter, connection, and spatial distribution of blood vessels. The new blood vessels were mainly capillaries and microvessels, with diameters ranging from 9 to 301 μm. The blood vessels with diameters from 27 to 155 μm accounted for 82.84% of the new vessels. The microvessels in the tissue-engineered nerves implanted in vivo were relatively well-identified using the MICROFIL perfusion and micro-CT scanning method, which allows the evaluation and comparison of differences and changes of angiogenesis in tissue-engineered nerves implanted in vivo.

Recently, metal-selective fluorescent chemosensors have attracted intense attention for their simple and real-time tracking of metal ions in environmental samples. However, most of the existing fluorescent sensors are one-off sensors and thus suffer from large amount of reagent consumption, significant experimental cost and raising the risk of environmental pollution. In this paper, we developed a green (low reagent consumption, low-toxicity reagent use), recyclable, and visual sensor for Cu(2+) in aqueous solution by using a fluorescent gold nanoclusters membrane (FGM) as the sensing unit, basing on our findings on gold nanoclusters (Au NCs) that the bovine serum albumin (BSA)-coated Au NCs exhibit excellent membrane-forming ability under the isoelectric point of BSA, and thus enable us to obtain a new type of sensing membrane (i.e. FGM) by denaturing Au NCs; the fluorescence of FGM can be significantly quenched by Cu(2+) ion, and the quenched fluorescence can be totally recovered by histidine; the as-prepared FGM is very stable and recyclable, which makes it an ideal sensing material.

OBJECTIVE To study the anti-tumor activity of SPS in vivo and in vitro and the cytotoxicity of CTL cells, NK cells of T739 lung cancer in mice. METHOD The transplanted tumor model of S180 Sarcoma was established with KM mouse. The SPS was adminished i.p. for 10 d, the tumor weight was detected. The transplanted tumor model of LA795 lung cancer was established with T739 mouse and SPS was adminished i.p. for 10 d and the tumor weight and the cytotoxicity of CTL cells, NK cells were detected. The Anti-tumor activity of SPS on three types of tumor cells in vitro was observed with trypan blue exclusion staining. RESULT SPS 40 mg x kg(-1) can significantly inhibit the growth of S180 Sarcoma in mice and inhibitory rate was 51.33% (P

Application of adult bone marrow stromal cells (BMSCs) provides therapeutic benefits to the treatment of neurological insults. The aim of this study was to explore the potential of nonhematopoietic BMSCs to produce soluble factors and stimulate signaling pathways in neurons that mediate trophic effects. A combination of enzyme-linked immunosorbent assay and two-dimensional gel electrophoresis coupled with mass spectrometry showed that the BMSCs released into the culture medium an array of soluble factors such as nerve growth factor, brain-derived neurotrophic factor, basic fibroblast growth factor, and ciliary neurotrophic factor, which have been shown to exhibit potent neurotrophic effects on neural cells. Immunochemistry, cell viability assay, and quantitative real-time RT-PCR collectively showed that neurite outgrowth and neurogenesis in cultured rat dorsal root ganglion (DRG) explants and neurons were enhanced after they were cocultured with rat BMSCs. Western blot analysis revealed that BMSC-conditioned medium activated phosphorylation of mitogen-activated protein kinase/extracellular signal-regulated protein kinase and/or phosphoinositide 3-kinase/serine/threonine kinase (PI3K/Akt) in primary culture of rat DRG neurons, which suggested that BMSCs trigger endogenous survival signaling pathways in neurons through their secreted soluble factors. Our data help to elucidate the mechanisms by which BMSCs function as a cell therapy agent in peripheral nerve regeneration.

A nanocomposite of ordered mesoporous pure anatase TiO2–C was successfully synthesized for the first time by using ordered mesoporous carbon as a nano-reactor and exhibited a short-range ordered mesoporous structure. It was found that carbon was coated on the surface of TiO2 nanoparticles to form a thin layer. Using this material as an anode in rechargeable lithium-ion batteries, it displayed a large reversible capacity, high rate performance and excellent long-term cycling stability. For instance, a large reversible capacity of 166 mA h g−1 and an average Coulombic efficiency of 99.7% could be maintained even after 900 cycles at a current rate of 1 C. This can be attributed to the structure of the ordered mesoporous TiO2–C nanocomposite. Such a nanostructure provides both electron and lithium-ion pathways which are essential for rechargeable lithium-ion batteries with a large capacity and excellent long-term performance.