Spontaneous thermal energy transfer and anti-gravitational water pumping using Al2O3 fiber-enhanced flexible nonwoven material as a high-performance and self-floating solar evaporator.

Solar-driven evaporation is promising to address water scarcity. However, preserving the heat inside evaporators instead of allowing run-off, and synergistically utilizing it to wick water from the bulk, is still underexplored. Herein, a dual-functional bridge of longitudinal orientated channels of Al2O3 fibers (AOFs) embedded in a multi-layered nonwoven evaporator was proposed to create a buffer for spontaneous thermal conduction and anti-gravitational water pumping. As a self-floating system with high porosity and flexibility, benefiting from the strong water transporting ability and high thermal conductivity of the AOFs, a superhigh evaporation rate (2.79 kg m-2 h-1 under 1 sun) can be achieved with great stability and durability. This work highlights the potential of promoting thermal management using a large-scale vapour chamber and mass-producible nonwoven technology to prepare a high-performance evaporator for practical applications.

Preparation of hydroxyapatite coated porous carbon nanofibres for DEX loading and enhancing differentiation of BMSCs.

The proliferation and differentiation of bone mesenchymal stem cells (BMSCs) in vitro are the key properties of bone tissue engineering for biomaterials. In this study, hydroxyapatite (HA) coated porous carbon nanofibres (PCNFs) were prepared to load dexamethasone (DEX) and further improve the differentiation ability of the BMSCs. Various characterisations were applied to reveal the DEX loading efficacy and biocompatibility, especially the differentiation strength. The results showed that HA could be successfully coated on the PCNFs by pretreating the surface using PEG conjugation. With an increase of HA, the particle diameter increased and the DEX loading decreased. In vitro experiments proved higher cell viability, alkaline phosphatase (ALP) activity, calcium nodule secretion ability and the RUNX2 protein expression, indicating that the as-prepared was of great biocompatibility and optimised osteoconductivity, which was attributed to the componential imitation to natural bone and the accelerated BMSCs differentiation. Consequently, the novel DEX loaded and HA coated PCNFs can provide potential applications in bone tissue regeneration.

Preparation of ZnO-Incorporated Porous Carbon Nanofibers and Adsorption Performance Investigation on Methylene Blue.

To improve the adsorption performance of carbon materials, novel ZnO nanoparticle-incorporated porous carbon nanofibers (Zn@PCNFs) were prepared via an electrospinning technique. A facile one-step fabrication strategy was proposed to simultaneously complete the carbonization of a peroxided polyacrylonitrile framework, the activating treatment caused by ZnO reducing to Zn, and the pore generation caused by evaporation of reduced Zn with a low melting point. The influences of the pH, ion category, and concentration on methylene blue adsorption were investigated. The physical-chemical characterizations showed that ZnO was homogeneously distributed on the nanofibers and micropores were generated. The adsorption results revealed that an efficient adsorption was obtained within a large range of pH values through different adsorption models, which was accelerated by increasing the temperature. Therefore, the novel Zn@PCNFs are anticipated to be applied in the future as an effective dye waste adsorbent.

The Construction of Multi-Incorporated Polylactic Composite Nanofibrous Scaffold for the Potential Applications in Bone Tissue Regeneration.

To improve the bone regeneration ability of pure polymer, varieties of bioactive components were incorporated to a biomolecular scaffold with different structures. In this study, polysilsesquioxane (POSS), pearl powder and dexamethasone loaded porous carbon nanofibers (DEX@PCNFs) were incorporated into polylactic (PLA) nanofibrous scaffold via electrospinning for the application of bone tissue regeneration. The morphology observation showed that the nanofibers were well formed through electrospinning process. The mineralization test of incubation in simulated body fluid (SBF) revealed that POSS incorporated scaffold obtained faster hydroxyapatite depositing ability than pristine PLA nanofibers. Importantly, benefitting from the bioactive components of pearl powder like bone morphogenetic protein (BMP), bone mesenchymal stem cells (BMSCs) cultured on the composite scaffold presented higher proliferation rate. In addition, by further incorporating with DEX@PCNFs, the alkaline phosphatase (ALP) level and calcium deposition were a little higher based on pearl powder. Consequently, the novel POSS, pearl powder and DEX@PCNFs multi-incorporated PLA nanofibrous scaffold can provide better ability to enhance the biocompatibility and accelerate osteogenic differentiation of BMSCs, which has potential applications in bone tissue regeneration.

Photothermal/pH Dual-Responsive Drug Delivery System of Amino-Terminated HBP-Modified rGO and the Chemo-Photothermal Therapy on Tumor Cells.

In this paper, a simple method to prepare hydrophilic reduced graphene oxide (rGO) was proposed via reducing GO by amino-terminated hyperbranched polymer (NHBP), the as-prepared NrGO could present excellent dispersibility, near infrared (NIR) light absorbance, photothermal conversion ability and stability. Then, the doxorubicin hydrochloride (DOX) was conjugated with NrGO to prepare the drug-loading system, and a pH/photothermal dual-responsive drug delivery behavior was characterized. At acidic environment or under NIR laser irradiation, the drug release rate could be improved, which is beneficial to control release anti-tumor drug in tumor tissues. What is more, the in vitro cell experiments revealed that NrGO was well biocompatible, and in the tumor inhibition part, comparing to the control group without any treatment, DOX@NrGO gained efficient chemo-photothermal synergetic therapy, the inhibition rate of which was much higher than single chemotherapy of released DOX. Therefore, the as-prepared DOX@NrGO obtained great potential application in tumor therapy and an excellent candidate in other biomed applications.

DNA vaccine and the CNS axonal regeneration.

Vaccines have been considered in treating many CNS degenerative disorders, including Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), epilepsy, multiple sclerosis (MS), spinal cord injury (SCI), and stroke. DNA vaccines have emerged as novel therapeutic agents because of the simplicity of their generation and application. Myelin components such as NOGO, MAG and OMGP are known to trigger demyelinating autoimmunity and to prevent axonal regeneration. For these reasons DNA vaccines encoding NOGO, MAG and OMGP, and fragments thereof, make them suitable vehicles for treatment of SCIs and MS. We need to obtain a deeper understanding of the immunologic mechanisms underlying the neuroprotective immunity to optimize the design of DNA vaccines for their use in clinical setting. In this review, we discuss recent findings suggesting that DNA vaccines hold a promising future for the treatment of axonal degeneration and demyelination.

Physiological roles of neurite outgrowth inhibitors in myelinated axons of the central nervous system--implications for the therapeutic neutralization of neurite outgrowth inhibitors.

It has long been recognized that the central nervous system (CNS) exhibits only limited capacity for axonal regeneration following injury. It has been proposed that myelin-associated inhibitory molecules are responsible for the nonpermissive nature of the CNS environment to axonal regeneration. Experimental strategies to enhance regeneration by neutralizing these inhibitory molecules are rapidly advancing toward clinical application. It is therefore important that the physiological distribution and functions of these supposed inhibitory molecules should be understood. In this review, we examine the distribution of these inhibitors of neurite outgrowth in relation to the longitudinal polarization of the myelinated axon into the node of Ranvier and associated domains and explore their potential domain specific physiological functions. Potential implications for the therapeutic strategy of neutralizing these inhibitory molecules to promote neural repair are discussed.

Oligodendrocytes regulate formation of nodes of Ranvier via the recognition molecule OMgp.

The molecular mechanisms underlying the involvement of oligodendrocytes in formation of the nodes of Ranvier (NORs) remain poorly understood. Here we show that oligodendrocyte-myelin glycoprotein (OMgp) aggregates specifically at NORs. Nodal location of OMgp does not occur along demyelinated axons of either Shiverer or proteolipid protein (PLP) transgenic mice. Over-expression of OMgp in OLN-93 cells facilitates process outgrowth. In transgenic mice in which expression of OMgp is down-regulated, myelin thickness declines, and lateral oligodendrocyte loops at the node-paranode junction are less compacted and even join together with the opposite loops, which leads to shortened nodal gaps. Notably, each of these structural abnormalities plus modest down-regulation of expression of Na(+) channel alpha subunit result in reduced conduction velocity in the spinal cords of the mutant mice. Thus, OMgp that is derived from glia has distinct roles in regulating nodal formation and function during CNS myelination.

Recombinant DNA vaccine encoding multiple domains related to inhibition of neurite outgrowth: a potential strategy for axonal regeneration.

Myelin-derived proteins, such as tenascin-R (TN-R), myelin associate glycoprotein (MAG), and Nogo-A, inhibit the CNS regeneration. By targeting specifically the inhibitory epitopes, we have investigated whether vaccination with a recombinant DNA molecule encoding multiple domains of myelin inhibitors may be useful in CNS repair. We show here that the recombinant DNA vaccine is able to activate the immune system but does not induce experimental autoimmune encephalomyelitis (EAE) in Lewis rats. Importantly, it promotes axonal regeneration in a spinal cord injury model. Thus, the application of DNA vaccine, encoding multiple specific domains of major inhibitory proteins and/or their receptors, provides another promising approach to overcome the inhibitory barriers during CNS regeneration.

Optic nerve regeneration in polyglycolic acid-chitosan conduits coated with recombinant L1-Fc.

Autografts have been extensively studied to facilitate optic nerve (ON) regeneration in animal experiments, but the clinical application of this approach to aid autoregeneration has not yet been attempted. This study aims to explore the guided regeneration by an artificial polyglycolic acid-chitosan conduit coated with recombinant L1-Fc. Consistent with previous studies; in vitro assay showed that both chitosan, a natural biomaterial, and the neural cell adhesion molecule L1-Fc enhanced neurite outgrowth. Rat optic nerve transection was used as an in vivo model. The implanted PGA-chitosan conduit was progressively degraded and absorbed, accompanied by significant axonal regeneration as revealed by immunohistochemistry, anterograde and retrograde tracing. The polyglycolic acid-chitosan conduit coated with L1-Fc showed more effective to promote axonal regeneration and remyelination. Taken together, our observations demonstrated that the L1-Fc coated PGA-chitosan conduits provided a compatible and supportive canal to guild the injured nerve regeneration and remyelination.

NB-3/Notch1 pathway via Deltex1 promotes neural progenitor cell differentiation into oligodendrocytes.

Neurons and glia in the vertebrate central nervous system arise in temporally distinct, albeit overlapping, phases. Neurons are generated first followed by astrocytes and oligodendrocytes from common progenitor cells. Increasing evidence indicates that axon-derived signals spatiotemporally modulate oligodendrocyte maturation and myelin formation. Our previous observations demonstrate that F3/contactin is a functional ligand of Notch during oligodendrocyte maturation, revealing the existence of another group of Notch ligands. Here, we establish that NB-3, a member of the F3/contactin family, acts as a novel Notch ligand to participate in oligodendrocyte generation. NB-3 triggers nuclear translocation of the Notch intracellular domain and promotes oligodendrogliogenesis from progenitor cells and differentiation of oligodendrocyte precursor cells via Deltex1. In primary oligodendrocytes, NB-3 increases myelin-associated glycoprotein transcripts. Thus, the NB-3/Notch signaling pathway may prove to be a molecular handle to treat demyelinating diseases.

Nogo-A at CNS paranodes is a ligand of Caspr: possible regulation of K(+) channel localization.

We report Nogo-A as an oligodendroglial component congregating and interacting with the Caspr-F3 complex at paranodes. However, its receptor Nogo-66 receptor (NgR) does not segregate to specific axonal domains. CHO cells cotransfected with Caspr and F3, but not with F3 alone, bound specifically to substrates coated with Nogo-66 peptide and GST-Nogo-66. Binding persisted even after phosphatidylinositol- specific phospholipase C (PI-PLC) removal of GPI-linked F3 from the cell surface, suggesting a direct interaction between Nogo-66 and Caspr. Both Nogo-A and Caspr co-immunoprecipitated with Kv1.1 and Kv1.2, and the developmental expression pattern of both paralleled compared with Kv1.1, implicating a transient interaction between Nogo-A-Caspr and K(+) channels at early stages of myelination. In pathological models that display paranodal junctional defects (EAE rats, and Shiverer and CGT(-/-) mice), distances between the paired labeling of K(+) channels were shortened significantly and their localization shifted toward paranodes, while paranodal Nogo-A congregation was markedly reduced. Our results demonstrate that Nogo-A interacts in trans with axonal Caspr at CNS paranodes, an interaction that may have a role in modulating axon-glial junction architecture and possibly K(+)-channel localization during development.