Natural killer (NK) cell is a specialized immune effector cell type that plays a critical role in immune activation against abnormal cells. Different from events required for T cell activation, NK cell activation is governed by the interaction of NK receptors with target cells, independent of antigen processing and presentation. Due to relatively unsophisticated cues for activation, NK cell has gained significant attention in the field of cancer immunotherapy. Many efforts are emerging for developing and engineering NK cell-based cancer immunotherapy. In this review, we provide our current understandings of NK cell biology, ongoing pre-clinical and clinical development of NK cell-based therapies and discuss the progress, challenges, and future perspectives.

Electrochemical desalination devices that use redox-active cation intercalation electrodes show promise for desalination of salt-rich water resources with high water recovery and low energy consumption. While previous modeling and experiments used ion-exchange membranes to maximize charge efciency, here a membrane-free alternative is evaluated to reduce capital cost by using a porous diaphragm to separate Na 1+x NiFe(CN) 6 electrodes. Two-dimensional porous-electrode modeling shows that, while charge efficiency losses are inherent to a diaphragm-based architecture, charge efficiency values approaching the anion transference number (61% for NaCl) are achievable for diaphragms with sufficiently low salt conductance. Closed-form equations are thereby derived that relate charge efficiency to the non-dimensional Pèclet and Damköhler numbers that enable the selection of current and flow velocity to produce a desired degree-of-desalination. Simulations using these conditions are used to quantify the tradeoffs between energy consumption and salt removal rate for diaphragmbased cells operated at a range of currents. The simulated distributions of reactions are shown to result from the local salt concentration variations within electrodes using diffusion-potential theory. We also simulate the cycling dynamics of various flow configurations and show that flow-through electrodes exceed the degree-of-desalination compared with flow-by and flow-behind configurations due to solution stagnation within electrodes.

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In clinics it is extremely important for implanted devices to achieve the property of enhanced lubrication and bacterial resistance; however, such a strategy has rarely been reported in previous literature. In the present study, a surface functionalization method, motivated by articular cartilage-inspired superlubrication and mussel-inspired adhesion, was proposed to modify titanium alloy (Ti6Al4V) using the copolymer (DMA–MPC) synthesized via free radical copolymerization. The copolymer-coated Ti6Al4V (Ti6Al4V@DMA–MPC) was evaluated by X-ray photoelectron spectroscopy, water contact angle, and Raman spectra to confirm that the DMA–MPC copolymer was successfully coated onto the Ti6Al4V substrate. In addition, the tribological test, with the polystyrene microsphere and Ti6Al4V or Ti6Al4V@DMA–MPC as the tribopair, indicated that the friction coefficient was greatly reduced for Ti6Al4V@DMA–MPC. Furthermore, the bacterial resistance test showed that bacterial attachment was significantly inhibited for Ti6Al4V@DMA–MPC for the three types of bacteria tested. The enhanced lubrication and bacterial resistance of Ti6Al4V@DMA–MPC was due to the tenacious hydration shell formed surrounding the zwitterionic charges in the phosphorylcholine group of the DMA–MPC copolymer. In summary, a bioinspired surface functionalization strategy is developed in this study, which can act as a universal and promising method to achieve enhanced lubrication and bacterial resistance for biomedical implants.

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Titanium and its alloys have long been used as implantable biomaterials in orthopedics; however, to the best of our knowledge, few studies were reported to investigate surface functionalization of titanium for enhanced lubrication and sustained drug release. In the present study, titania nanotube arrays (TNTs) were prepared by anodization as effective drug nanocarriers, using titanium as the substrate. Meanwhile, motivated by articular cartilage-inspired superlubricity and mussel-inspired adhesion, a copolymer containing both dopamine methacrylamide and 2-methacryloyloxyethyl phosphorylcholine was synthesized (DMA−MPC) and spontaneously grafted onto the TNT surface, which was validated by characterization techniques such as scanning electron microscopy, water contact angle measurements, and X-ray photoelectron spectroscopy. Additionally, the lubrication test showed that copolymer-grafted TNTs have remarkably reduced friction coefficients compared with bare TNTs. Furthermore, the drug release test demonstrated that copolymer-grafted TNTs inhibited burst drug release and achieved sustained drug release in comparison with bare TNTs. In conclusion, the bioinspired surface functionalization strategy developed here, namely DMA−MPC copolymer-grafted TNTs, can be applied to modify orthopedic biomaterials (such as titanium) for enhanced lubrication and sustained drug release.

Introduction Rambling natural landscapes or landscape gardens may invoke positive emotions. However, the manner in which people experience landscape gardens and the cortical differences in the appreciation of the naturalness and artificiality of landscapes remain unknown. Methods This study scanned participants with functional magnetic resonance imaging while they viewed photographs of natural landscapes and landscape gardens and performed scene type judgment task. Results As predicted, we identified brain regions that were associated with perceptual process, cognitive process, and rewarding experience when appreciating natural landscapes and landscape gardens without color preference. Meanwhile, the contrast between the appreciation of landscape gardens and natural landscapes was characterized by stronger activations of the inferior occipital lobe, the left superior parietal lobule (SPL), the right fusiform gyrus, the right cuneus, and the right hippocampus. Conclusions Responses in these regions indicate that the appreciation of landscape gardens and natural landscapes relies on common cortical regions, and suggest the possibility that the inferior occipital lobe, the SPL, the fusiform gyrus, and the cuneus may be specifically associated with the appreciation of landscape gardens.