Saikosaponin B2, Punicalin, and Punicalagin in Vitro Block Cellular Entry of Feline Herpesvirus-1.

In the realm of clinical practice, nucleoside analogs are the prevailing antiviral drugs employed to combat feline herpesvirus-1 (FHV-1) infections. However, these drugs, initially formulated for herpes simplex virus (HSV) infections, operate through a singular mechanism and are susceptible to the emergence of drug resistance. These challenges underscore the imperative to innovate and develop alternative antiviral medications featuring unique mechanisms of action, such as viral entry inhibitors. This research endeavors to address this pressing need. Utilizing Bio-layer interferometry (BLI), we meticulously screened drugs to identify natural compounds exhibiting high binding affinity for the herpesvirus functional protein envelope glycoprotein B (gB). The selected drugs underwent a rigorous assessment to gauge their antiviral activity against feline herpesvirus-1 (FHV-1) and to elucidate their mode of action. Our findings unequivocally demonstrated that Saikosaponin B2, Punicalin, and Punicalagin displayed robust antiviral efficacy against FHV-1 at concentrations devoid of cytotoxicity. Specifically, these compounds, Saikosaponin B2, Punicalin, and Punicalagin, are effective in exerting their antiviral effects in the early stages of viral infection without compromising the integrity of the viral particle. Considering the potency and efficacy exhibited by Saikosaponin B2, Punicalin, and Punicalagin in impeding the early entry of FHV-1, it is foreseeable that their chemical structures will be further explored and developed as promising antiviral agents against FHV-1 infection.

An Accurate and Transferable Coarse-Graining Method for the Investigation of Microscopic Fracture Behaviors of Epoxy Thermosets.

Coarse-grained modeling shows potential in exploring the thermo-mechanical behaviors of polymers applied in harsh conditions such as cryogenic environment, but its accuracy in simulating fracture behaviors of highly cross-linked epoxy thermosets is largely limited due to the complex molecular structures of the cross-linked networks. We address this fundamental problem by developing a CG modeling method where the backbones and electrostatic interaction (EI) contributions in the cross-linked networks are retained, and thus the potentials of the CG model can be directly extracted, or parametrized on the basis of, existing all-atomistic (AA) force fields. A multilevel parametrization procedure was adopted, where the bond potentials were parametrized relying on the results of density functional theory (DFT) simulation, whereas the nonbond potentials were parametrized by renormalizing the cohesive interaction strength. Remarkably, the CG model can reproduce stress-strain responses highly consistent with the AA simulation results at multiple stages, including elastic deformation, yielding, plastic flow, strain hardening, etc., and the straightforward parametrization procedure can be easily transferred to different materials and thermodynamic conditions. The CG modeling method was then used to build a large-scale representative volume element (RVE) to investigate the microscopic fracture behavior of an epoxy thermoset. It has been discovered that EI contributions play a significant role in generating correct mechanical responses and fracture morphologies. The influences of temperature (i.e., from room to cryogenic temperatures) and strain rates were discussed, and the fracture morphology in the RVE was unveiled and analyzed in a quantitative manner.

Exploring PLGA-OH-CATH30 Microspheres for Oral Therapy of Escherichia coli-Induced Enteritis.

Antibiotic therapy effectively addresses Escherichia coli-induced enteric diseases, but its excessive utilization results in microbial imbalance and heightened resistance. This study evaluates the therapeutic efficacy of orally administered poly (lactic-co-glycolic acid) (PLGA)-loaded antimicrobial peptide OH-CATH30 microspheres in murine bacterial enteritis. Mice were categorized into the healthy control group (CG), untreated model group (MG), OH-CATH30 treatment group (OC), PLGA-OH-CATH30 treatment group (POC), and gentamicin sulfate treatment group (GS). Except for the control group, all other experimental groups underwent Escherichia coli-induced enteritis, followed by a 5-day treatment period. The evaluation encompassed clinical symptoms, intestinal morphology, blood parameters, inflammatory response, and gut microbiota. PLGA-OH-CATH30 microspheres significantly alleviated weight loss and intestinal damage while also reducing the infection-induced increase in spleen index. Furthermore, these microspheres normalized white blood cell count and neutrophil ratio, suppressed inflammatory factors (IL-1ß, IL-6, and TNF-α), and elevated the anti-inflammatory factor IL-10. Analysis of 16S rRNA sequencing results demonstrated that microsphere treatment increased the abundance of beneficial bacteria, including Phocaeicola vulgatus, in the intestinal tract while concurrently decreasing the abundance of pathogenic bacteria, such as Escherichia. In conclusion, PLGA-OH-CATH30 microspheres have the potential to ameliorate intestinal damage and modulate the intestinal microbiota, making them a promising alternative to antibiotics for treating enteric diseases induced by Escherichia coli.

Research Note: Isolation and immunomodulatory activity of bursal peptide, a novel peptide from avian immune system developments.

The bursa of Fabricius (BF) is pivotal for B lymphocyte ontogenesis. In the present investigation, a novel bursal peptide, designated BP7, was extracted from BF and was found to stimulate colony-forming unit pre-B (CFU pre-B) formation at various concentrations (1 µg/mL, P < 0.05; 5 µg/mL, P < 0.05; 25 µg/mL, P < 0.05). Moreover, BP7 modulated B cell differentiation pathways. The immunoregulatory potential of BP7 was further assessed in avian and murine models subjected to immunization with inactivated avian influenza virus (AIV, H9N2 subtype). BP7 significantly augmented AIV-specific antibody levels (Prime immunization: 5 mg/kg, P < 0.05; Boost immunization: 0.4, 1, and 5 mg/kg, P < 0.05) and cytokine secretion in the avian model (IL-4 and IFN-γ: 0.4, 1, and 5 mg/kg, P < 0.05). Similarly, in the murine model, AIV-specific antibody levels (Prime and Boost immunization: 0.4, 1, and 5 mg/kg, P < 0.05) and cytokine production (IL-4 and IFN-γ: 0.4, 1, and 5 mg/kg, P < 0.05) were notably enhanced. This study offers novel insights into the mechanisms underlying B cell maturation and holds implications for future immunopharmacological interventions.

Assessing the Efficacy of PLGA-Loaded Antimicrobial Peptide OH-CATH30 Microspheres for the Treatment of Bacterial Keratitis: A Promising Approach.

Bacterial keratitis in animals presents challenges due to ocular structural barriers, hindering effective drug delivery. In this study, we used biocompatible and biodegradable poly(lactic-co-glycolic acid) (PLGA) to encapsulate the naturally occurring antimicrobial peptide OH-CATH30, an alternative to conventional antibiotics, for the treatment of bacterial keratitis in animals. Microspheres (MS) were prepared using a modified water-in-oil-in-water (W/O/W) double-emulsion method with optimized osmotic pressure. We conducted comprehensive evaluations, including in vitro characterization, encapsulation efficiency determination, in vitro release kinetics, and in vivo/vitro assessments of irritation and bacterial inhibition. The optimized method yielded microspheres with impressive encapsulation efficiency of 75.2 ± 3.62% and a loading capacity of 18.25 ± 5.73%, exhibiting a well-defined particle size distribution (200-1000 nm) and a ζ-potential of -17.3 ± 1.91 mV. The microspheres demonstrated initial burst release followed by sustained and controlled release in vitro. Both in vitro and in vivo tolerance tests confirmed the biocompatibility of the drug-loaded microspheres, as they did not elicit significant irritation in ocular tissues. Remarkable antibacterial effects were observed in both in vitro and in vivo experiments. Our developed PLGA microspheres show promise as an alternative therapeutic option for topical administration in managing keratitis, offering exceptional drug delivery capabilities, improved bioavailability, and potent antibacterial efficacy.

Impact of 1,25-dihydroxyvitamin D3 PLGA-nanoparticles/chitosan hydrogel on osteoimmunomodulation.

Severe bone defects that extend beyond a critical size do not heal on their own, increasing the risk of complications and leading to poor outcomes for patients. Healing is a highly coordinated and complex process in which immune cells have an important function making the design and preparation of biomaterials with immunomodulatory functions an important new therapeutic strategy. 1,25-dihydroxyvitamin D3 (VD3) is crucial for bone metabolism and immune regulation. For post-defect bone regeneration, we developed a drug delivery system (DDS) based on chitosan (CS) and nanoparticles (NPs) to sustain the release effect of VD3 and desirable biological characteristics. The hydrogel system was physically characterized and confirmed to have good mechanical strength, degradation rate, and drug release rate. In vitro experiments showed that the cells had good biological activity when the hydrogel was co-cultured with MC3T3-E1 and RAW264.7. The high expression of ARG-1 and low expression of iNOS in macrophages confirmed that VD3-NPs/CS-GP hydrogel transformed lipopolysaccharide-induced M1 macrophages into M2 macrophages. Alkaline phosphatase and alizarin red staining showed that VD3-NPs/CS-GP hydrogel promoted osteogenic differentiation under inflammatory conditions. In conclusion, VD3-NPs/CS-GP hydrogel with synergistic anti-inflammatory and pro-osteogenic differentiation effects may serve as a potential immunomodulatory biomaterial for bone repair and regeneration in cases of bone defects.

Boosting the electrochemical performance of Li-rich Mn-based cathode materials via oxygen vacancy and spinel phase integration.

Li-rich Mn-based oxide cathodes (LMOs) are regarded as one of the most prospective high energy density cathodes due to the reversible anion redox reaction, which gives them a very high capacity. However, LMOs materials usually have problems like low initial coulombic efficiency (ICE) and poor cycling performance during cycling, which are associated with irreversible surface O2 release and unfavourable electrode/electrolyte interface side reactions. Herein, an innovative and scalable NH4Cl-assisted gas-solid interfacial reaction treatment technique is employed to construct oxygen vacancies and spinel/layered heterostructures simultaneously on the surface of LMOs. The synergistic effect of the oxygen vacancy and the surface spinel phase can not only effectively enhance the redox properties of the oxygen anion and inhibit irreversible oxygen release, but also effectively mitigate the side reactions at the electrode/electrolyte interface, inhibit the formation of CEI films and stabilize the layered structure. The electrochemical performance of the treated NC-10 sample improved significantly, showing an increase in ICE from 77.4 % to 94.3 % and excellent rate capability and cycling stability, with a capacity retention of 77.9 % after 400 cycles at 1 C. This oxygen vacancy and spinel phase integration strategy offers an exciting prospect and avenue for improving the integrated electrochemical performance of LMOs.

High expression of antimicrobial peptides cathelicidin-BF in Pichia pastoris and verification of its activity.

Antibacterial peptides are endogenous polypeptides produced by multicellular organisms to protect the host against pathogenic microbes, they show broad spectrum antimicrobial activities against various microorganisms and possess low propensity for developing resistance. The purpose of this study is to develop recombinant antibacterial peptide cathelicidin-BF by genetic engineering and protein engineering technology, and study its antibacterial activity in vitro and in vivo, so as to provide reference for the production and application of recombinant antibacterial peptide cathelicidin-BF. In this study, on account of Pichia pastoris eukaryotic expression system, we expressed and prepared antibacterial peptide cathelicidin-BF. Then, the minimum inhibitory concentration of antibacterial peptide cathelicidin-BF and the comparison with the antibacterial activity of antibiotics were determined through the antibacterial experiment in vitro. Chickens as infection model were used to verify the antibacterial peptide activity in vivo. The results show that the bacteriostatic ability of antibacterial peptide cathelicidin-BF is similar to that of antibiotics in certain concentration, and can reach the treatment level of antibiotics. Although the mode of administration of antibacterial peptide is still limited, this study can provide reference for the future research of antibacterial peptide.

Hydrogel electrodes with conductive and substrate-adhesive layers for noninvasive long-term EEG acquisition.

Noninvasive brain-computer interfaces (BCIs) show great potential in applications including sleep monitoring, fatigue alerts, neurofeedback training, etc. While noninvasive BCIs do not impose any procedural risk to users (as opposed to invasive BCIs), the acquisition of high-quality electroencephalograms (EEGs) in the long term has been challenging due to the limitations of current electrodes. Herein, we developed a semidry double-layer hydrogel electrode that not only records EEG signals at a resolution comparable to that of wet electrodes but is also able to withstand up to 12 h of continuous EEG acquisition. The electrode comprises dual hydrogel layers: a conductive layer that features high conductivity, low skin-contact impedance, and high robustness; and an adhesive layer that can bond to glass or plastic substrates to reduce motion artifacts in wearing conditions. Water retention in the hydrogel is stable, and the measured skin-contact impedance of the hydrogel electrode is comparable to that of wet electrodes (conductive paste) and drastically lower than that of dry electrodes (metal pin). Cytotoxicity and skin irritation tests show that the hydrogel electrode has excellent biocompatibility. Finally, the developed hydrogel electrode was evaluated in both N170 and P300 event-related potential (ERP) tests on human volunteers. The hydrogel electrode captured the expected ERP waveforms in both the N170 and P300 tests, showing similarities in the waveforms generated by wet electrodes. In contrast, dry electrodes fail to detect the triggered potential due to low signal quality. In addition, our hydrogel electrode can acquire EEG for up to 12 h and is ready for recycled use (7-day tests). Altogether, the results suggest that our semidry double-layer hydrogel electrodes are able to detect ERPs in the long term in an easy-to-use fashion, potentially opening up numerous applications in real-life scenarios for noninvasive BCI.

Pt Nanoflowers as a Highly Effective Electrocatalyst for Glucose Oxidation in Abiotic Glucose Fuel Cells.

Self-powered implantable medical devices (IMDs) without any external power supply are desired in a growing number of situations. Glucose fuel cells (GFCs) that convert the chemical energy of intrinsic glucose and oxygen into electricity are promising technology to achieve this goal. Herein, a Pt nanoflower (Pt NF) catalyst is prepared by using a facile one-step reduction method and employed as the anode catalyst for abiotic GFCs in a neutral environment at a physiological concentration of glucose. The Pt NF catalyst exhibits high electrocatalytic activity, catalytic selectivity, and good durability in the electrochemical analysis. The Pt NF's rapid linear current response to the variation of glucose concentration within a wide range also makes it a promising material for glucose sensors. A GFC with two chambers fabricated with a Pt NF catalyst-decorated carbon paper (Pt NFs/CP) anode and a Pt sheet cathode generates a maximum power density (Pmax) of 13.8 µW cm-2, an open-circuit voltage (VOC) of 819.5 mV, and a short-circuit current density (JSC) of 0.12 mA cm-2, which makes it a viable candidate for application in self-powered devices.

Preparation of a SiO2 @Carbon Sphere/SiO2 -CNF Multilayer Self-standing Anode Prepared via an Alternate Electrospraying - Electrospinning Technique.

The development of flexible lithium-ion batteries (FLIBs) is restrained by traditional rigidity anodes. Carbon nanofiber (CNF) is a promising anode material owing to its high specific surface and superior ion transportation capability. However, the low amount of active material loaded on the CNFs and the poor stability during long cycling restrain their applications. Herein, a SiO2 @carbon sphere/SiO2 -CNF self-standing anode was prepared via alternate electrospraying-electrospinning. The SiO2 content of the anode was increased through the electrospraying SiO2 @carbon spheres layers, and the electrospun SiO2 -CNFs as robust layers enhanced the stability of the anode. The self-standing anode exhibited 633 mA h g-1 in the initial cycle and maintained a 70% Coulomb efficiency for 1000 cycles at a current density of 100 mA g-1 , which could be applied in FLIB and other electrochemical storage devices.

Magnetorheological properties of Fe-Co nanoparticles with high saturation magnetization and low coercivity.

Fe-Co alloys exhibit an excellent saturation magnetization, which makes them become a potential candidate for the high property magnetic particles in magnetorheological fluids (MRFs). How to decrease their coercivity and residual magnetization without sacrificing the saturation magnetization is a crucial problem to be solved. In this study, Fe-Co nanoparticles were prepared by DC arc discharge and further disposed through low temperature annealing in Ar atmosphere. The successful synthesis of Fe-Co nanoparticles was proved by x-ray diffraction and EDS. The vibrating sample magnetometer results revealed that the prepared Fe-Co nanoparticles had a saturation magnetization of 208 emu g-1, while the coercivity and remanent magnetization were 58 Oe and 5.8 emu g-1, respectively. The MR properties of Fe-Co nanoparticles based MRFs (FeCoNP-MRFs) with 10% particles by volume fraction were systematically investigated. The FeCoNP-MRFs showed up to 4.61 kPa dynamic shear stress at 436 kA m-1magnetic field and an excellent reversibility. The MR properties of FeCoNP-MRFs were fitted well by Bingham and power law model, and described by Seo-Seo and Casson fluid model. Meanwhile, the sedimentation ratio of FeCoNP-MRFs was still 87.3% after 72 h, indicating an excellent sedimentation stability.

Self-Sensing Cementitious Composites with Hierarchical Carbon Fiber-Carbon Nanotube Composite Fillers for Crack Development Monitoring of a Maglev Girder.

In view of high-performance, multifunctional, and low-carbon development of infrastructures, there is a growing demand for smart engineering materials, making infrastructures intelligent. This paper reports a new-generation self-sensing cementitious composite (SSCC) incorporated with a hierarchically structured carbon fiber (CF)-carbon nanotube (CNT) composite filler (CF-CNT), which is in situ synthesized by directly growing CNT on CF. Various important factors including catalyst, temperature, and gas composition are considered to investigate their kinetic and thermodynamic influence on CF-CNT synthesis. The reciprocal architecture of CF-CNT not only alleviates the CNT aggregation, but also significantly improves the interfacial bonding between CF-CNT and matrix. Due to the synergic and spatially morphological effects of CF-CNT, that is, the formation of widely distributed multiscale reinforcement networks, SSCCs with CF-CNTs exhibit high mechanical properties and electrical conductivity as well as excellent self-sensing performances, particularly enhanced sensing repeatability. Moreover, the SSCCs with CF-CNTs are integrated into a full-scale maglev girder to devise a smart system for crack development monitoring. The system demonstrates high sensitivity and fidelity to capture the initiation of cracks/damage, as well as progressive and sudden damage events until the complete failure of the maglev girder, indicating its considerable potential for structural health monitoring of infrastructures.

Mussel-Inspired Calcium Alginate/Polyacrylamide Dual Network Hydrogel: A Physical Barrier to Prevent Postoperative Re-Adhesion.

Intrauterine adhesions (IUA) has become one of the main causes of female infertility. How to effectively prevent postoperative re-adhesion has become a clinical challenge. In this study, a mussel-inspired dual-network hydrogel was proposed for the postoperative anti-adhesion of IUA. First, a calcium alginate/polyacrylamide (CA-PAM) hydrogel was prepared via covalent and Ca2+ cross-linking. Benefiting from abundant phenolic hydroxyl groups, polydopamine (PDA) was introduced to further enhance the adhesion ability and biocompatibility. This CA-PAM hydrogel immersed in 10 mg/mL dopamine solution possessed remarkable mechanical strength (elastic modulus > 5 kPa) and super stretchability (with a breaking elongation of 720%). At the same time, it showed excellent adhesion (more than 6 kPa). Surprisingly, the coagulation index of the hydrogel was 27.27 ± 4.91, demonstrating attractive coagulation performance in vitro and the potential for rapid hemostasis after surgery.

The Synthesis of Carbon Black-Loaded Pt Concave Nanocubes with High-Index Facets and Their Enhanced Electrocatalytic Properties toward Glucose Oxidation.

Catalysts with high catalytic activity and good stability are desirable in the electrocatalytic oxidation of glucose. Herein, Pt concave nanocubes with high-index facets (HIFs) supported by carbon black (Pt CNC/CB) are prepared through a hydrothermal method. The experimental results demonstrate that the peak current densities in different potential regions on the Pt CNC/CB anode are 0.22, 0.20, and 0.60 mA cm-2. The catalytic process of the glucose oxidation reaction is investigated in electrolytes with different pH values. Better stability is achieved by Pt CNC/CB than by Pt concave nanocubes (Pt CNCs). Abundant surface defects with low-coordinated atom numbers, such as steps, kinks, and edges, served as active sites in the electrocatalytic oxidation of glucose. With the addition of carbon black, the catalytic activity can be improved by facilitating the full exposure of the active surface defects on the HIFs of the Pt CNCs. Moreover, to address the aggregation of Pt CNCs, caused by the high surface energy of HIFs, the introduction of carbon material is an effective way to preserve the HIFs and thus enhance the stability of the catalyst. Hence, the prepared Pt CNC/CB electrocatalyst has great potential to be applied in the electrooxidation of glucose.

Promoting the Oxygen Evolution Reaction via Morphological Manipulation of a Lamellar Nanorod-Assembled Ni(II)-Pyrazolate Superstructure.

Nanoscale pyrazolate-based coordination polymers (CPs) are becoming increasingly popular as electrocatalysts owing to their customizable compositions and structures. However, using them for oxygen evolution reaction (OER) is highly challenging due to their unsatisfactory catalytic efficiency and relatively low stability. Herein, a simple one-step solvothermal process was employed for the fabrication of polycrystalline nickel-pyrazolate [Ni(Pz)] with an unusual lamellar nanorod-assembled microsphere morphology for the first time using ethanol as a green organic solvent via controlling other physical parameters. Meanwhile, the Ni(Pz) structure and morphology are investigated to derive its formation process following the different monomeric feed ratios relying on the metal/ligand interactions of CP. Shaping the Ni(Pz) electrocatalyst in well-oriented lamellar nanorod-assembled microspheres brings the advantage of porosity and high specific surface area, which expedites mass/charge transport and contact with the electrolyte as well as creates less tortuous pathways for charge distribution, thus improving the charge homogeneity. These high-class structural features and polycrystalline nature of Ni(Pz)-E-PVP facilitate amazing catalytic OER activity with a low overpotential of 290 mV at 10 mA cm-2 and a Tafel slope of only 94 mV dec-1 beyond the yardstick material (i.e., RuO2) in alkaline solution. A suite of measurements, entailing X-ray photoelectron spectroscopy and density functional theory calculations, suggest that the rich Ni-N4 moieties in Ni(Pz)-E-PVP are central species providing adsorption sites for OER intermediates. This facile protocol is prophesied to commence the imminent development of noble metal-free, effective, and low-priced electrocatalysts for OER.

Effect of viscoelastic properties of cellulose nanocrystal/collagen hydrogels on chondrocyte behaviors.

Cartilage tissue engineering technology provides a solution for treating osteoarthritis. Based on the viscoelastic nature of articular cartilage, many viscoelastic hydrogel scaffolds have been developed for investigating the effects on chondrocyte behaviors. However, cellulose nanocrystal/collagen (CNC/COL) hydrogels have not been used as a viscoelastic microenvironment to study chondrocyte growth. Here, we prepared CNC/COL hydrogels with tunable viscoelastic properties and investigated their influences on chondrocyte behaviors. The results showed that CNC and COL within the hydrogels are bonded by hydrogen bonds. The hydrogels had a microporous structure, and the viscoelastic properties were enhanced by increasing the concentration of CNC. Moreover, enhancing the hydrogel viscoelastic properties, including stress relaxation, creep, storage modulus, and loss modulus, promoted the cell shape change, proliferation, and matrix deposition and reduced the IL-1ß level. Using a principal component analysis (PCA), stress relaxation was assessed to have the strongest correlation with chondrocytes behaviors, with an authority weight value of 62.547%. More importantly, FAK and YAP were involved in the chondrocytes' response to the rapid relaxing hydrogel by immunofluorescence staining.

The porous spongy nest structure compressible anode fabricated by gas forming technique toward high performance lithium ions batteries.

The state-of-the-art electronics promote the development of flexible and deformable batteries, which rely on design of advanced structure batteries and fabrication of suitable electrode materials. The current flexible electronics are generally limited by rigidity and nondeformable electrodes. Herein, this work reports an exceeding compressible spongy carbon nanofibers composite anode which was fabricated by electrospinning and gas-forming techniques. The abundant macro/micro porous and loss structure of spongy layers enable the composite electrode exhibited compressible capability and faster ions infiltration ability. And the nest morphology of spongy carbon nanofibers network promised stable conductivity and superior cycling performance of self-standing anodes. The compressible SnO2@spongy carbon nanofibers and SiO2@spongy carbon nanofibers self-standing anode exhibited outstanding cycling ability before 300 cycles under compressed state, with a capacity of 350 and 398 mA h g-1, respectively. Notably, the stress and strain of compressible spongy composite electrode are 370 kPa and 92%, separately, with recovery ability. The compressible spongy anode is highly recommended for flexible electrochemical energy storage devices and the novel gas-forming technique is a potential method for fabrication of multi morphology electrode.

Exosome-functionalized magnesium-organic framework-based scaffolds with osteogenic, angiogenic and anti-inflammatory properties for accelerated bone regeneration.

Exosomes derived from human adipose-derived stem cells (hADSCs-Exos) have shown potential as an effective therapeutic tool for repairing bone defects. Although metal-organic framework (MOF) scaffolds are promising strategies for bone tissue regeneration, their potential use for exosome loading remains unexplored. In this study, motivated by the potential advantages of hADSCs-Exos and Mg-GA MOF, we designed and synthesized an exosome-functionalized cell-free PLGA/Mg-GA MOF (PLGA/Exo-Mg-GA MOF) scaffold, taking using of the benefits of hADSCs-Exos, Mg2+, and gallic acid (GA) to construct unique nanostructural interfaces to enhance osteogenic, angiogenic and anti-inflammatory capabilities simultaneously. Our in vitro work demonstrated the beneficial effects of PLGA/Exo-Mg-GA MOF composite scaffolds on the osteogenic effects in human bone marrow-derived mesenchymal stem cells (hBMSCs) and angiogenic effects in human umbilical endothelial cells (HUVECs). Slowly released hADSCs-Exos from composite scaffolds were phagocytosed by co-cultured cells, stabilized the bone graft environment, ensured blood supply, promoted osteogenic differentiation, and accelerated bone reconstruction. Furthermore, our in vivo experiments with rat calvarial defect model showed that PLGA/Exo-Mg-GA MOF scaffolds promoted new bone formation and satisfactory osseointegration. Overall, we provide valuable new insights for designing exosome-coated nanocomposite scaffolds with enhanced osteogenesis property.

Molecular Dynamics Simulations and Experimental Studies of the Microstructure and Mechanical Properties of a Silicone Oil/Functionalized Ionic Liquid-Based Magnetorheological Fluid.

Magnetorheological (MR) fluids are smart materials that show enormous potential in vibration control, mechanical engineering, etc. However, the effects of the solid-liquid interface strength and the interaction strength between carrier liquid molecules on the mechanical properties and sedimentation stability of MR fluids have always been unresolved issues. This work presents a new type of MR fluid that has a novel carrier liquid, i.e., silicone oil (SO) mixed with a hydroxyl-functionalized ionic liquid (IL-OH). An all-atomic Fe/SO/IL-OH interface model for studying the relationship between mechanical properties and interface strength and intermolecular interactions is established. On the basis of simulation results and theoretical analyses, the mechanical properties and sedimentation stability of the SO/IL-OH-based MR fluids are thoroughly investigated by experiments. The results show that functional ionic liquids significantly improve the mechanical properties and sedimentation stability of MR fluids. These results are essentially attributed to the stronger solid-liquid interface strength, van der Waals forces, and hydrogen bonds between the silicone oil and the functional ionic liquid. The explicit results not only help elucidate the numerous phenomena involved in the research process for MR fluids at the atomic scale but also provide insightful information on the fabrication of high-performance MR fluids.