Biodegradable Polymeric Nanoparticles Containing an Immune Checkpoint Inhibitor (aPDL1) to Locally Induce Immune Responses in the Central Nervous System

Immunotherapy is an efficient approach to clinical oncology. However, the immune privilege of the central nervous system (CNS) limits the application of immunotherapeutic strategies for brain cancers, especially glioblastoma (GBM). Tumor resistance to immune checkpoint inhibitors is a further challenge in immunotherapies. To overcome the immunological tolerance of brain tumors, a novel multifunctional nanoparticle (NP) for highly efficient synergetic immunotherapy is reported. The NP contains an anti-PDL1 antibody (aPDL1), upconverting NPs, and the photosensitizer 5-ALA; the surface of the NP is conjugated with the B1R kinin ligand to facilitate transport across the blood-tumor-barrier. Upon irradiation with a 980 nm laser, 5-ALA is transformed into protoporphyrin IX, generating reactive oxygen species. Photodynamic therapy (PDT) further promotes intratumoral infiltration of cytotoxic T lymphocytes and sensitizes tumors to PDL1 blockade therapy. It is demonstrated that combining PDT and aPDL1 can effectively suppress GBM growth in mouse models. The proposed NPs provide a novel and effective strategy for boosting anti-GBM photoimmunotherapy.     

Interfacial microstructure and mechanical properties of Ti3SiC2 ceramic and TC11 alloy joint diffusion bonded with a Cu interlayer

Reliable joints of Ti₃SiC₂ ceramic and TC11 alloy were diffusion bonded with a 50 μm thick Cu interlayer. The typical interfacial structure of the diffusion boned joint, which was dependent on the interdiffusion and chemical reactions between Al, Si and Ti atoms from the base materials and Cu interlayer, was TC11/α-Ti + β-Ti + Ti₂Cu + TiCu/Ti₅Si₄ + TiSiCu/Cu(s, s)/Ti₃SiC₂. The influence of bonding temperature and time on the interfacial structure and mechanical properties of Ti₃SiC₂/Cu/TC11 joint was analyzed. With the increase of bonding temperature and time, the joint shear strength was gradually increased due to enhanced atomic diffusion. However, the thickness of Ti₅Si₄ and TiSiCu layers with high microhardness increased for a long holding time, resulting in the reduction of bonding strength. The maximum shear strength of 251 ± 6 MPa was obtained for the joint diffusion bonded at 850 °C for 60 min, and fracture primarily occurred at the diffusion layer adjacent to the Ti₃SiC₂ substrate. This work provided an economical and convenient solution for broadening the engineering application of Ti₃SiC₂ ceramic.     

A Bi-Enzymatic Cascade Pathway towards Optically Pure FAHFAs**

Recently discovered endogenous mammalian lipids, fatty acid esters of hydroxy fatty acids (FAHFAs), have been proved to have anti-inflammatory and anti-diabetic effects. Due to their extremely low abundancies in vivo, forging a feasible scenario for FAHFA synthesis is critical for their use in uncovering biological mechanisms or in clinical trials. Here, we showcase a fully enzymatic approach, a novel in vitro bi-enzymatic cascade system, enabling an effective conversion of nature-abundant fatty acids into FAHFAs. Two hydratases from Lactobacillus acidophilus were used for converting unsaturated fatty acids to various enantiomeric hydroxy fatty acids, followed by esterification with another fatty acid catalyzed by Candida antarctica lipase A (CALA). Various FAHFAs were synthesized in a semi-preparative scale using this bi-enzymatic approach in a one-pot two-step operation mode. In all, we demonstrate that the hydratase-CALA system offers a promising route for the synthesis of optically pure structure-diverse FAHFAs.     

Fabrication of Nd-doped Ni–Zn ferrite/multi-walled carbon nanotubes composites with effective microwave absorption properties

The electromagnetic materials are featured by good magnetic permeability and dielectric constant characteristics, which are of significant importance in solving the pollution problem of electromagnetic. In this study, after the complete of the use of sol-gel method, argon gas was then introduced for calcination, and eventually a new type of MWCNTs/Ni_0.5Zn_0.5Nd_0.04Fe_1.96O₄ composites was synthesized after the above mentioned procedures. The synthesized MWCNTs were able to be adsorbed on the surface of Ni_0.5Zn_0.5Nd_0.04Fe_1.96O₄ and could form a good conductive work of 3D. Also, the effect of additional MWCNTs on microwave absorption properties of MWCNTs/Ni_0.5Zn_0.5Nd_0.04Fe_1.96O₄ composites were also observed in this study. The results indicate that the additional MWCNTs function to significantly improve the microwave absorption property of MWCNTs/Ni_0.5Zn_0.5Nd_0.04Fe_1.96O₄. Through altering the amount of MWCNTs, the microwave attenuation performance and impedance matching coefficient of this electromagnetic materials can be effectively improved. The S2 sample presented a minimum reflection loss of ?35.05 dB when its thickness reached 1.6 mm, meanwhile, the effective absorption bandwidth achieved 4.55 GHz. The prepared composites perform well in microwave absorption, which can attribute to the reasonable ratio of composites as well as its interaction with both of the magnetic and dielectric components. This research paved the way for novel ideas to be put in the electromagnetic absorption materials with high-efficient.     

Targeted Delivery of Anesthetic Agents to Bone Tissues using Conductive Microneedles Enhanced Iontophoresis for Painless Dental Anesthesia

Pain management during dental procedures is a cornerstone for successful daily practice. In current practice, the traditional needle and syringe injection is used to administer local anesthesia. However, the appearance of long needles and the pain associated with it often leads to dental anxiety deterring timely interventions. Microneedles (MNs) have emerged as a minimally invasive alternative to hypodermic needles and shown to be effective in transdermal drug delivery applications. In this article, the potential use of MNs for local anesthesia delivery in dentistry is explored. The development of a novel conductive MN array that can be used in combination with iontophoresis technique to achieve drug penetration through the oral mucosa and the underlying bone tissue is presented. The conductive MN array plays a dual-role, creating micro-conduits and lowering the resistance of the oral mucosa. The reduced tissue resistance further enhances the application of a low-voltage current that is able to direct and accelerate the drug molecules to target the sensory nerves supplying teeth. The successful delivery of lidocaine using this new strategy in a clinically relevant rabbit incisor model is shown to be as effective as the current gold standard.     

Toward High-Performance Dihydrophenazine-Based Conjugated Microporous Polymer Cathodes for Dual-Ion Batteries through Donor–Acceptor Structural Design

Recent studies have demonstrated that dihydrophenazine (Pz) with high redox-reversibility and high theoretical capacity is an attractive building block to construct p-type polymer cathodes for dual-ion batteries. However, most reported Pz-based polymer cathodes to date still suffer from low redox activity, slow kinetics, and short cycling life. Herein, a donor–acceptor (D–A) Pz-based conjugated microporous polymer (TzPz) cathode is constructed by integrating the electron-donating Pz unit and the electron-withdrawing 2,4,6-triphenyl-1,3,5-triazine (Tz) unit into a polymer chain. The D–A type structure enhances the polymer conjugation degree and decreases the band gap of TzPz, facilitating electron transportation along the polymer skeletons. Therefore the TzPz cathode for dual-ion battery shows a high reversible capacity of 192 mAh g⁻¹ at 0.2 A g⁻¹ with excellent rate performance (108 mAh g⁻¹ at 30 A g⁻¹), which is much higher than that of its counterpart polymer BzPz produced from 1,3,5-triphenylbenzene (Bz) and Pz (148 and 44 mAh g⁻¹ at 0.2 and 10 A g⁻¹, respectively). More importantly, the TzPz cathode also shows a long and stable cyclability of more than 10 000 cycles. These results demonstrate that the D–A structural design is an efficient strategy for developing high-performance polymer cathodes for dual-ion batteries.     

Effects of the joining process on the microstructure and properties of liquid-phase-sintered SiC-SiC joints formed with Ti foil

The joining of liquid-phase sintered SiC (LPS-SiC) ceramics was conducted using spark plasma sintering (SPS), through solid state diffusion bonding, with Ti-metal foil as a joining interlayer. Samples were joined at 1400 °C, under applied pressures of either 10 or 30 MPa, and with different atmospheres (argon, Ar, vs. vacuum). It was demonstrated that the shear strength of the joints increased with an increase in the applied joining pressure. The joining atmosphere also affected on both the microstructure and shear strength of the SiC joints. The composition and microstructure of the interlayer were examined to understand the mechanism. As a result, a SiC-SiC joining with a good mechanical performance could be achieved under an Ar environment, which in turn could provide a cost-effective approach and greatly widen the applications of SiC ceramic components with complex shape.     

Surface modification of superfine SiC powders by ternary modifiers-KH560/sodium humate/SDS and its mechanism

SiC is a promising functional ceramic material with many great properties. High concentrated SiC slurry with excellent rheology and stability is required in some processes of ceramic forming. In this work, the dispersion of SiC powders was obviously improved by ternary modifiers: γ-(2,3-epoxypropoxy) propytrimethoxysilane (KH560), sodium humate and sodium dodecyl sulfate (SDS). Modified SiC slurry showed the lowest viscosity of 0.168 Pa s at a solid content of 50 vol%. The maximum absolute value of zeta potential of SiC increased from 47.3 to 61.6 mV by modification. Sedimentation experiments showed that a highly stable suspension of modified SiC was obtained at pH 10. SiC green body with high density of 2.643 g/cm³ was prepared with modified powders by slip casting. X-ray photoelectron spectra (XPS) and thermogravimetry (TG) measurements indicated the adsorption of modifiers on SiC surface. Therefore, modified SiC powders could stably disperse in aqueous media due to the increase of electrosteric repulsion between particles. The novel strategy used in this study could further improve the dispersion of SiC powders.