Multifunctional Flame-Retardant Melamine-Based Hybrid Foam for Infrared Stealth, Thermal Insulation, and Electromagnetic Interference Shielding.

Multifunctionalization is an important development direction of electromagnetic interference (EMI)-shielding materials. However, it is still a huge challenge to effectively integrate multiple functions into materials. Herein, we reported a facile method to fabricate multifunctional EMI-shielding materials, which were assembled with multidimensional components consisting of a 3D melamine-formaldehyde (MF) foam skeleton, 0D ferroferric oxide (FeO) nanoparticles, and 1D silver nanowires (AgNWs) via coprecipitation and dip-coating processes.

Multifunctional Photothermal Conversion Nanocoatings Toward Highly Efficient and Safe High-Viscosity Oil Cleanup Absorption.

Efficient and safe cleanup for the high-viscosity heavy oil spill has been a worldwide challenge due to its sluggish flowability, while classic absorption methods by electric/solar heating are seriously limited by low efficiency and high fire hazards during heating of highly flammable oil. Facing this dilemma, we reported a novel flame-retardant photothermal conversion nanocoating to endow commercial foams with highly efficient and safe heavy oil cleanup absorption. This multifunctional nanocoating consisting of nano-FeO and reduced graphene oxide (rGO) that both showed photothermal conversion ability and non-flammable nature can be firmly deposited on the polymer foam skeletons via facile coprecipitation and dip-coating processes.

Phenotype Regulation of Smooth Muscle Cells Through Facial Crystallization of Poly(-Caprolactone).

Phenotype conversion of smooth muscle cells (SMCs) plays a key role in the formation of atherosclerosis. Understanding how SMCs respond to a micro/nano-topology and elucidating the cellular mechanism of phenotype conversion is critical to the atherosclerosis treatment. Herein, we prepared poly(-caprolactone) (PCL) spherulites with a radius more than 350 m for the studying of radial microstructure influence on SMCs behaviors.

Integration of Cell-Penetrating Peptides with Rod-like Bionanoparticles: Virus-Inspired Gene-Silencing Technology.

Inspired by the high gene transfer efficiency of viral vectors and to avoid side effects, we present here a 1D rod-like gene-silencing vector based on a plant virus. By decorating the transacting activator of transduction (TAT) peptide on the exterior surface, the TAT-modified tobacco mosaic virus (TMV) achieves a tunable isoelectric point (from ∼3.5 to ∼9.

Balancing antimicrobial activity with biological safety: bifunctional chitosan derivative for the repair of wounds with Gram-positive bacterial infections.

Infection control and the promotion of healing are two key factors during the wound repair process. However, it is still a major challenge for one material to inhibit bacterial growth efficiently and promote wound healing at the same time. Here, a bifunctional chitosan derivative (CS-G/mPEG) was prepared by the successive modification of chitosan with carboxymethoxypolyethylene glycol (mPEG-COOH) and aminoiminomethanesulfonic acid (AIMSOA).

Tuning Alginate-Gelatin Bioink Properties by Varying Solvent and Their Impact on Stem Cell Behavior.

Bioink optimization is considered as one of main challenges in cell-laden 3D bioprinting. Alginate-Gelatin (Alg-Gel) hydrogel have been extensively used as bioink. However, its properties could be influenced by various parameters, and little is known about the evidence featuring the impact of solvent.

[Effect of aging on proliferative and differentiation capacity of human periodontal ligament stem cells].

Objective: To evaluate the effect of aging on the proliferative and differentiation capacity of human periodontal ligament stem cells (PDLSCs).

Methods: Human periodontal ligament tissues were obtained from surgically extracted third molars from 6 subjects aged 18-20 years (group A) and 6 subjects aged 45-50 years (group B). The proliferative capacity of PDLSCs isolated from the tissues was examined with MTT assay, and the osteogenic and adipogenic differentiation capacity of the cells were evaluated using alizarin red staining and oil red O staining.

Communication between nitric oxide synthase and positively-charged surface and bone formation promotion.

Despite the effects on physiology of bone marrow mesenchymal stem cells (BMSCs) and bone tissue, biological signal communication between bone implants and them is seldom employed as a guidance to create an osteo-inductive interface. Herein, the positively-charged surface is constructed on bone implant from the perspective of mediation of nitric oxide synthase (NOS) expression to signal BMSCs osteo-differentiation. In vitro and in vivo results indicate that the proper surface potential on the positively-charged surface affects NOS to express a high level of inducible nitric oxide synthase (iNOS) in three NOS isoforms of the contacted BMSCs, upregulates their osteogenetic expression, and ultimately foster new bone growth.

Brain and muscle aryl hydrocarbon receptor nuclear translocator-like protein-1 cooperates with glycogen synthase kinase-3β to regulate osteogenesis of bone-marrow mesenchymal stem cells in type 2 diabetes.

Type 2 diabetes mellitus (T2DM) is associated with inhibited osteogenesis of bone marrow mesenchymal stem cells (BMSCs). Brain and muscle ARNT-like protein 1 (BMAL1) has been linked to the T2DM-related bone remodeling, however, the specific mechanism is still unclear. Herein, we aimed to determine the role of BMAL1 in T2DM-induced suppression of BMSCs osteogenesis.

Influence of the intensity and loading time of direct current electric field on the directional migration of rat bone marrow mesenchymal stem cells.

Exogenic electric fields can effectively accelerate bone healing and remodeling through the enhanced migration of bone marrow mesenchymal stem cells (BMSCs) toward the injured area. This study aimed to determine the following: (1) the direction of rat BMSC (rBMSC) migration upon exposure to a direct current electric field (DCEF), (2) the optimal DCEF intensity and duration, and (3) the possible regulatory role of SDF-1/CXCR4 axis in rBMSC migration as induced by DCEF. Results showed that rBMSCs migrated to the positive electrode of the DCEF, and that the DCEF of 200 mV/mm for 4 h was found to be optimal in enhancing rBMSC migration.

[Difference of in vitro osteogenic differentiation and osteoclast capacity between stem cells from human exfoliated deciduous teeth and dental pulp stem cells].

Objective: To compare the osteogenic differentiation potential and osteoclast capacity between stem cells from human exfoliated deciduous teeth (SHED) in the physiological root resorption period and dental pulp stem cells (DPSCs).

Methods: SHED and DPSCs were isolated, purified and cultured in vitro. The two stem cells were examined with ALP staining at 14 days and with alizarin red staining at 21 days of osteogenic induction, and the expressions of the genes associated with osteogenesis and osteoclastogenesis were detected using real-time PCR.

In situ plasma fabrication of ceramic-like structure on polymeric implant with enhanced surface hardness, cytocompatibility and antibacterial capability.

Polymeric materials are commonly found in orthopedic implants due to their unique mechanical properties and biocompatibility but the poor surface hardness and bacterial infection hamper many biomedical applications. In this study, a ceramic-like surface structure doped with silver is produced by successive plasma implantation of silicon (Si) and silver (Ag) into the polyamine 66 (PA66) substrate. Not only the surface hardness and elastic modulus are greatly enhanced due to the partial surface carbonization and the ceramic-like structure produced by the reaction between energetic Si and the carbon chain of PA66, but also the antibacterial activity is improved because of the combined effects rendered by Ag and SiC structure.

High glucose microenvironments inhibit the proliferation and migration of bone mesenchymal stem cells by activating GSK3β.

Diabetes mellitus involves metabolic changes that can impair bone repair. Bone mesenchymal stem cells (BMSCs) play an important role in bone regeneration. However, the bone regeneration ability of BMSCs is inhibited in high glucose microenvironments.

Upregulation of BMSCs osteogenesis by positively-charged tertiary amines on polymeric implants via charge/iNOS signaling pathway.

Positively-charged surfaces on implants have a similar potential to upregulate osteogenesis of bone marrow-derived mesenchymal stem cells (BMSCs) as electromagnetic therapy approved for bone regeneration. Generally, their osteogenesis functions are generally considered to stem from the charge-induced adhesion of extracellular matrix (ECM) proteins without exploring the underlying surface charge/cell signaling molecule pathways. Herein, a positively-charged surface with controllable tertiary amines is produced on a polymer implant by plasma surface modification.

Effects of plasma-generated nitrogen functionalities on the upregulation of osteogenesis of bone marrow-derived mesenchymal stem cells.

Because of the complex plasma reactions and chemical structures of polymers, it is difficult to construct nitrogen functionalities controllably by plasma technology to attain the desirable biological outcome and hence, their effects on bone cells are sometimes ambiguous and even contradictory. In this study, argon plasma treatment is utilized to convert complex molecular chains into a pyrolytic carbon structure which possesses excellent cytocompatibility. The pyrolytic carbon then serves as a platform to prepare the desired nitrogen functionalities by nitrogen and hydrogen plasma immersion ion implantation.

Antibacterial and osteoinductive capability of orthopedic materials via cation-π interaction mediated positive charge.

Both implant centered infection and deficient osteoinduction are pivotal issues for orthopedic implants in early and long-term osseointegration, but constructing a functional bio-interface that can overcome these two problems is highly challenging. Our study reveals that a bio-interface with promoted positive charges plays an active role in simultaneously enhancing the antibacterial and osteoinductive capability of orthopedic implants. The positively charged bio-interface is fabricated by a simple dipping method, in which the cationic polymer (polyhexamethylene biguanidine, PHMB) is immobilized in the conjugated polydopamine coating.

Mesenchymal stem cells prevent hypertrophic scar formation via inflammatory regulation when undergoing apoptosis.

The cutaneous wound-healing process can lead to hypertrophic scar formation, during which exaggerated inflammation has been demonstrated to have an important role. Therefore, an exploration of strategies designed to regulate this inflammatory process is warranted. Mesenchymal stem cells (MSCs) have recently been demonstrated to regulate inflammation in various diseases.

Electrospun tubular scaffold with circumferentially aligned nanofibers for regulating smooth muscle cell growth.

Simulation for the smooth muscle layer of blood vessel plays a key role in tubular tissue engineering. However, fabrication of biocompatible tube with defined inner nano/micro-structure remains a challenge. Here, we show that a biocompatible polymer tube from poly(l-lactide) (PLLA) and polydimethylsiloxane (PDMS) can be prepared by using electrospinning technique, with assistance of rotating collector and parallel auxiliary electrode.

Hetero-epitaxy of anisotropic polycaprolactone films for the guidance of smooth muscle cell growth.

An anisotropic biocompatible composite PCL-PTFE film was used to guide smooth muscle cell outgrowth along defined directions.

Scaffold-free cell pellet transplantations can be applied to periodontal regeneration.

Cell transplantation has emerged as a novel therapeutic strategy for periodontitis, and the adoption of cell pellet offers advantages by secreting abundant extracellular matrix (ECM) and eliminating the adverse effect of cell carriers. This study aimed to fabricate scaffold-free periodontal ligament stem cell (PDLSC) pellets (MUCPs) and to evaluate their regeneration potential. We constructed monolayer cell pellets (MCPs) by fabricating and culturing multilayered cell sheets (MUCS) and constructed MUCPs from the MUCS.

Tailoring of mesenchymal stem cells behavior on plasma-modified polytetrafluoroethylene.

By altering the surface properties of polytetrafluoroethylene (PTFE) substrates using a special PIII technique, mesenchymal stem cells (MSCs) proliferation and osteogenesis can be promoted in culture without osteogenic supplements. The structures are created intrinsically in the PTFE for no risk of materials delamination. Large-scale features and locally different functions can also be readily produced on the same substrate by this technique.

Dental follicle cells and treated dentin matrix scaffold for tissue engineering the tooth root.

Tissue engineering strategies to reconstruct tooth roots are an effective therapy for the treatment of tooth loss. However, strategies to successfully regenerate tooth roots have not been developed and optimized. In the present study, rat dental follicle stem cells (DFCs) were characterized, followed by a thorough investigation of tooth roots regeneration for a combination of DFCs seeding cells, treated dentin matrix (TDM) scaffolds, and an inductive alveolar fossa microenvironment.

High levels of β-catenin signaling reduce osteogenic differentiation of stem cells in inflammatory microenvironments through inhibition of the noncanonical Wnt pathway.

Periodontal ligament stem cells (PDLSCs), a new population of mesenchymal stem cells (MSCs), have been isolated from the periodontal ligament (PDL). The capacity of multipotency and self-renewal makes them an excellent cell source for bone regeneration and repair. However, their bone-regeneration ability could be awakened in inflammatory microenvironments, which may be the result of changes in their differentiation potential.