Harnessing strategies for enhancing diabetic wound healing from the perspective of spatial inflammation patterns

Diabetic wound is a great threat to patient’s health and lives.The refractory diabetic wound shows spatial inflammation patterns,in which the early-wound pattern depicts a deprived acute inflammatory response,and the long-term non-healing wound pattern delineates an excessive and persistent inflammation due to the delayed immune cell infiltration in a positive feedback loop.In this work,we give points to some strategies to normalize the dysregulated immune process based on the spatial inflammation pattern differences in diabetic wound healing.First of all,inhibiting inflammatory response to avoid subsequent persistent and excessive immune infiltration for the early diabetic wound is proposed.However,diabetic wounds are unperceptive trauma that makes patients miss the best treatment time.Therefore,we also introduce two strategies for the long-term non-healing diabetic wound.One strategy is about changing chronic wounds to acute ones,which aims to rejuvenate M1 macrophages in diabetic wounds and make spontaneous M2 polarization possible.To activate the controllable proinflammatory response,western medicine delivers proinflammatory molecules while traditional Chinese medicine develops“wound-pus promoting granulation tissue growth theory”.Another strategy to solve long-term non-healing wounds is seeking switches that target M1/M2 transition directly.These investigations draw a map that delineates strategies for enhancing diabetic wound healing from the perspective of spatial inflammation patterns systematically.

Fabrication of magnesium-doped porous polylactic acid microsphere for bone regeneration

Biodegradable polymer microspheres that can be used as drug carriers are of great importance in biomedical applications,however,there are still challenges in controllable preparation of microsphere surface morphology and improvement of bioactivity.In this paper,firstly,poly(L-lactic acid)(PLLA)was synthesised by ring-opening polymerisation under anhydrous anaerobic conditions and further combined with the emulsion method,biodegradable PLLA microspheres(PM)with sizes ranging from 60-100μm and with good sphericity were prepared.In addition,to further improve the surface morphology of PLLA microspheres and enhance their bioactivity,functionalised porous PLLA microspheres loaded with magnesium oxide(MgO)/magnesium carbonate(MgCO_(3))(PMg)were also prepared by the emulsion method.The results showed that the loading of MgO/MgCO_(3)resulted in the formation of a porous structure on the surface of the microspheres(PMg)and the dissolved Mg^(2+)could be released slowly during the degradation of microspheres.In vitro cellular experiments demonstrated the good biocompatibility of PM and PMg,while the released Mg^(2+)further enhanced the anti-inflammatory effect and osteogenic activity of PMg.Functionalised PMg not only show promise for controlled preparation of drug carriers,but also have translational potential for bone regeneration.

Advances in electrode interface materials and modification technologies for brain-computer interfaces

Recent advances in neuroelectrode interface materials and modification technologies are reviewed. Brain-computer interface is the new method of human-computer interaction, which not only can realise the exchange of information between the human brain and external devices, but also provides a brand-new means for the diagnosis and treatment of brain-related diseases. The neural electrode interface part of brain-computer interface is an important area for electrical, optical and chemical signal transmission between brain tissue system and external electronic devices, which determines the performance of brain-computer interface. In order to solve the problems of insufficient flexibility, insufficient signal recognition ability and insufficient biocompatibility of traditional rigid electrodes, researchers have carried out extensive studies on the neuroelectrode interface in terms of materials and modification techniques. This paper introduces the biological reactions that occur in neuroelectrodes after implantation into brain tissue and the decisive role of the electrode interface for electrode function. Following this, the latest research progress on neuroelectrode materials and interface materials is reviewed from the aspects of neuroelectrode materials and modification technologies, firstly taking materials as a clue, and then focusing on the preparation process of neuroelectrode coatings and the design scheme of functionalised structures.

A suture-free, shape self-adaptive and bioactive PEG-Lysozyme implant for Corneal stroma defect repair and rapid vision restoration

limitation of donor tissue shortage clinically. In addition, suturing-needed transplantation potentially causes postoperative complications. Herein, we design a PEG-Lysozyme injective hydrogel as a suture-free, shape self-adaptive, bioactive implant for corneal stroma defect repair. This implant experiences a sol-gel phase transition via an in situ amidation reaction between 4-arm-PEG-NHS and lysozyme. The physicochemical properties of PEG-Lysozyme can be tuned by the components ratio, which confers the implant mimetic corneal modulus and provides tissue adhesion to endure increased intraocular pressure. In vitro tests prove that the implant is beneficial to Human corneal epithelial cells growth and migration due to the bioactivity of lysozyme. Rabbit lamellar keratoplasty experiment demonstrates that the hydrogel can be filled into defect to form a shape-adaptive implant adhered to native stroma. The implant promotes epithelialization and stroma integrity, recovering the topology of injured cornea to normal. A newly established animal forging behavior test prove a rapid visual restoration of rabbits when use implant in a suture free manner. In general, this work provides a promising preclinical practice by applicating a self-curing, shape self-adaptive and bioactive PEG-Lysozyme implant for suture-free stroma repair.

Size-transformable nanoparticles with sequentially triggered drug release and enhanced penetration for anticancer therapy

There are several limitations to the application of nanoparticles in the treatment of cancer,including their low drug loading,poor colloidal stability,insufficient tumor penetration,and uncontrolled release of the drug.Herein,gelatin/laponite(LP)/doxorubicin(GLD)nanoparticles are developed by crosslinking LP with gelatin for doxorubicin delivery.GLD shows high doxorubicin encapsulation efficacy(99%)and strong colloidal stability,as seen from the unchanged size over the past 21 days and reduced protein absorption by 48-fold compared with unmodified laponite/doxorubicin nanoparticles.When gelatin from 115 nm GLD reaches the tumor site,matrix metallopeptidase-2(MMP-2)from the tumor environment breaks it down to release smaller 40 nm LP nanoparticles for effective tumor cell endocytosis.As demonstrated by superior penetration in both in vitro three-dimensional(3D)tumor spheroids(138-fold increase compared to the free drug)and in vivo tumor models.The intracellular low pH and MMP-2 further cause doxorubicin release after endocytosis by tumor cells,leading to a higher inhibitory potential against cancer cells.The improved anticancer effectiveness and strong in vivo biocompatibility of GLD have been confirmed using a mouse tumor-bearing model.MMP-2/pH sequentially triggered anticancer drug delivery is made possible by the logical design of tumor-penetrating GLD,offering a useful method for anticancer therapy.