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Biogenic collagen membranes have been widely used as soft tissue barriers in guided bone regeneration (GBR) and guided tissue regeneration (GTR). Nevertheless, their clinical performance remains unsatisfactory because of their low mechanical strength and fast degradation rate in vivo. Although cross-linking with chemical agents is effective and reliable for prolonging the degradation time of collagen membranes, some adverse effects including potential cytotoxicity and undesirable tissue integration have been observed during this process. As a fundamental nutritional trace element, zinc plays an active role in promoting the growth of cells and regulating the degradation of the collagen matrix. Herein, a biogenic collagen membrane was cross-linked with glutaraldehyde-alendronate to prolong its degradation time. The physiochemical and biological properties were enhanced by the incorporation of zinc-doped nanohydroxyapatite (nZnHA), with the native structure of collagen preserved. Specifically, the cross-linking combined with the incorporation of 1% and 2% nZnHA seemed to endow the membrane with the most appropriate biocompatibility and tissue integration capability among the cross-linked membranes, as well as offering a degradation period of six weeks in a rat subcutaneous model. Thus, improving the clinical performance of biogenic collagen membranes by cross-linking together with the incorporation of nZnHA is a promising strategy for the improvement of biogenic collagen membranes. STATEMENT OF SIGNIFICANCE: The significance of this research includes.

Micro/nano topographic structures have shown great utility in many biomedical areas including cell therapies, tissue engineering, and implantable devices. Computer-assisted informatics methods hold great promise for the design of topographic structures with targeted properties for a specific medical application. To benefit from these methods, researchers and engineers require a highly reusable “one structural parameter – one set of cell responses” database. However, existing confounding factors in topographic cell culture devices seriously impede the acquisition of this kind of data. Through carefully dissecting the confounding factors and their possible reasons for emergence, we developed corresponding guideline requirements for topographic cell culture device development to remove or control the influence of such factors. Based on these requirements, we then suggested potential strategies to meet them. In this work, we also experimentally demonstrated a topographic cell culture device with controlled confounding factors based on these guideline requirements and corresponding strategies. A “guideline for the development of topographic cell culture devices” was summarized to instruct researchers to develop topographic cell culture devices with the confounding factors removed or well controlled. This guideline aims to promote the establishment of a highly reusable “one structural parameter – one set of cell responses” database that could facilitate the application of informatics methods, such as artificial intelligence, in the rational design of future biotopographic structures with high efficacy., Graphical abstract Image 1

Due to their good mechanical performances and high biocompatibility, all-ceramic materials are widely applied in clinics, especially in orthopedic and dental areas. However, the "hard" property negatively affects its integration with "soft" tissue, which greatly limits its application in soft tissue-related areas. For example, dental implant all-ceramic abutments should be well integrated with the surrounding gingival soft tissue to prevent the invasion of bacteria. Mimicking the gingival soft tissue and dentine integration progress, we applied the modified ion-exchange technology to "activate" the biological capacity of lithium disilicate glass-ceramics, via introducing OH

The paradoxical effect of cobalt on biological processes has aroused controversy regarding the application of cobalt-based biomaterials in bone regeneration. Tuning the dose range of cobalt ions may be a valid strategy to resolve the controversies about cobalt use for orthopedic applications. Recent progress in bone biology has highlighted the effects of multisystem cooperation (especially of osteoimmune, skeletal, and vascular systems) on bone dynamics. Before the application of this dose-tuning strategy, a deeper understanding of its dose-dependent effect on the cooperation of osteoimmune, skeletal, and vascular systems is needed. However, due to the difficulties with investigating the interaction of multiple systems in vitro, the multimodal effects of cobalt on bone homeostasis were investigated here, in an in vivo scenario. Methods: In vitro CCK8 assay and cytoskeletal staining were preformed to detecte the cell cytotoxic reaction in response to 0.1-100 ppm cobalt stimulation. Blood clot containing 0.1 to 5 ppm of cobalt were implanted in the rat calvarium defect. The gene profile of osteoimmune, skeletal, and vascular system as well as the systemic toxicity were evaluated via RT-qPCR, histological analysis and inductively coupled plasma mass spectrometry. The bone regeneration, osteoclastogenesis and vascularization were assessed by micro-ct and histological analysis. Results: Cobalt concentration below 5 ppm did not cause cell toxicity in vitro. No systemic toxicity was observed in vivo at 0.1-5 ppm cobalt concentration. It was found that the early cytokine profiles of the multiple interacting systems were different in response to different cobalt doses. Most of the anti-inflammatory, osteogenic, and proangiogenic factors were upregulated in the 1 ppm cobalt group at the early stage. In the late stage, the 1ppm group was most superior in bone regenerative effect while the 5 ppm group displayed the strongest osteoclastogenesis activity. Conclusions: The 1 ppm concentration of cobalt yielded the most favorable cooperation of the osteoimmune, skeletal, and vascular systems and subsequently optimal bone regeneration outcomes. Tuning the cobalt dose range to manipulate the cooperation of osteoimmune, skeletal, and vascular systems could be a promising and valuable strategy to prevent paradoxical effects of cobalt while preserving its beneficial effects.

Soft tissue integration is one major difficulty in the wide applications of metal materials in soft tissue-related areas. The inevitable inflammatory response and subsequent fibrous reaction toward the metal implant is one key response for metal implant-soft tissue integration. It is of great importance to modulate this inflammatory-fibrous response, which is mainly mediated by the multidirectional interaction between fibroblasts and macrophages. In this study, macrophages are induced to generate M1 and M2 macrophage immune microenvironments. Their cytokine profiles have been proven to have potentially multi-regulatory effects on fibroblasts. The multi-reparative effects of soft tissue cells (human gingival fibroblasts) cultured on metal material (titanium alloy disks) in M1 and M2 immune microenvironments are then dissected. Fibroblasts in the M1 immune microenvironment tend to aggravate the inflammatory response in a pro-inflammatory positive feedback loop, while M2 immune microenvironment enhances multiple functions of fibroblasts in soft tissue integration, including soft tissue regeneration, cell adhesion on materials, and contraction to immobilize soft tissue. Enlighted by the close interaction between macrophages and fibroblasts, we propose the concept of an "inflammatory-fibrous complex" to disclose possible methods of precisely and effectively modulating inflammatory and fibrous responses, thus advancing the development of metal soft tissue materials.

Formation of blood clots, particularly the fibrin network and fibrin network‐mediated early inflammatory responses, plays a critical role in determining the eventual tissue repair or regeneration following an injury. Owing to the potential role of fibrin network in mediating clot‐immune responses, it is of great importance to determine whether clot‐immune responses can be regulated via modulating the parameters of fibrin network. Since the diameter of D‐terminal of a fibrinogen molecule is 9 nm, four different pore sizes (2, 8, 14, and 20 nm) are rationally selected to design mesoporous silica to control the fibrinogen adsorption and modulate the subsequent fibrin formation process. The fiber becomes thinner and the contact area with macrophages decreases when the pore diameters of mesoporous silica are greater than 9 nm. Importantly, these thinner fibers grown in pores with diameters larger than 9 nm inhibit the M1‐polorazation of macrophages and reduce the productions of pro‐inflammatory cytokines and chemokines by macrophages. These thinner fibers reduce inflammation of macrophages through a potential signaling pathway of cell adhesion‐cytoskeleton assembly‐inflammatory responses. Thus, the successful regulation of the clot‐immune responses via tuning of the mesoporous pore sizes indicates the feasibility of developing advanced clot‐immune regulatory materials., Tuning mesoporous silica pore size is found to affect blood clot coagulation and change fibrin network structure through regulating fibrinogen adsorption. The regulated fibrin network further modulates the immune response of macrophage via a potential pathway of cell adhesion‐cytoskeleton assembly‐inflammatory response, indicating a feasible strategy to develop advanced clot‐immune regulatory materials.

In this work, the influence of solvothermal crystallization processes on the microstructure, pore characteristic, and adsorption/photocatalysis of SiO2-W0.02TiO2.06 composite aerogels synthesized via ambient pressure drying have been investigated. It has been clarified that the composite aerogels prepared via solvothermal crystallization at 120 °C for 0.5 h and 180 °C for 3 h exhibited high-specific surface area (416–729 m2/g) and pore volume (2.26–2.70 cm3/g). With the increase of solvothermal crystallization temperature and time, the crystallinity of composite aerogels increased gradually, but excessive solvothermal crystallization time at higher temperature decreased the pore volume greatly. Furthermore, it is found that bacterial cellulose (BC) in the composite gel plays an important role in enhancing the pore volume and crystallization of the SiO2-W0.02TiO2.06 composite aerogels as a pore-expanding agent and structure-directing agent. The as-synthesized SiO2-W0.02TiO2.06 composite aerogels exhibited higher adsorption and removal efficiency for RhB than the commercial P25-TiO2, which can be ascribed to its high pore volume and specific surface area, as well as the synergistic action of adsorption and photocatalysis.

In this paper, silica aerogels and carbon aerogels were prepared by ambient pressure drying and freeze drying, respectively. The microstructure and adsorption capability of the two kinds of aerogels for antibiotics in water were investigated. The results showed that silica aerogels and carbon aerogels exhibited completely different adsorption capability for antibiotics although they possessed similar specific surface area (665–765 m2/g) and pore volume (1.6–3.0 cm3/g). The silica aerogel, no matter how they are hydrophobic or hydrophilic, both showed much lower adsorption rate for antibiotics than the carbon aerogel. By contrast, the carbon aerogel and magnetic carbon aerogel both showed excellent adsorption performance for antibiotics, with the adsorption rate for terramycin within 180 min attaining to 99.9%. The adsorption mechanism of terramycin on the two kinds of aerogels was studied using kinetic adsorption models. It has been clarified that the adsorption process of the two aerogels is mainly based on chemical adsorption with the assistance of physical adsorption. Moreover, the carbon aerogel exhibited higher adsorption stability for antibiotics without desorption phenomenon, and the magnetic carbon aerogels have excellent recycling utilization performance.

In order to further improve the flexural strength of lithium disilicate glass-ceramic, surface strengthening by ion exchange using Rb, Cs nitrates has been studied for the first time. The influences of ion exchange using rubidium and cesium salts on the flexural strength and corrosion resistance have been investigated. It was found that the mechanical properties of the lithium disilicate glass-ceramic could be increased greatly by the ion exchange in rubidium nitrate (RbNO3) salt. After ion exchange for 4 h in RbNO3 salt, the flexural strength and microhardness increased from 169 MPa and 587 kgf mm−2 (5.75 Gpa) of the original lithium disilicate glass-ceramic to 493 MPa and 654 kgf mm−2 (6.4 Gpa), respectively. Moreover, the corrosion resistance of the lithium disilicate glass-ceramic was further improved by ion exchange in rubidium and cesium nitrate salts. Furthermore, the maximum thickness of the ion exchange layer using RbNO3 and CsNO3 was only 4.3 µm and 0.45 µm respectively. Such a thin exchange layer, which will only require very low Rb+, Cs+ ions exchange amount, indicates that the molten salts of RbNO3 and CsNO3 can be reused for many times. So it is suggested that surface strengthening of lithium disilicate glass-ceramic by ion exchange using Rb, Cs nitrates is cost-efficient and very suitable for the actual production and applications.

The lithium disilicate (LD) glass-ceramics with the SiO2-Li2O-R2O-Al2O3-P2O5-CeO2 system were prepared by adding R2O (R = K, Rb, Cs) as modifier. The effects of R2O addition on the crystallization behavior, microstructure and fracture strength of the LD glass-ceramics were investigated by differential thermal analysis (DTA), X-ray diffraction (XRD) and scanning electron microscopy (SEM) etc. The results indicate that the fracture strength of LD glass-ceramics could be improved greatly by introducing Rb2O or Cs2O instead of K2O, therein, introducing Rb2O instead of K2O improved the fracture strength by 26% and Cs2O substituting K2O improved the fracture strength by 37%. The crystallization activation energy of different crystal phase was calculated. It was found that the lower the crystallization activation energy of lithium disilicate is, the higher the fracture strength of LD glass-ceramic achieves. Based on the results, a new chemical strengthening theory of LD glass-ceramic has been proposed, which is of great significance for developing LD dental restorative materials and other functional glasses.

In order to obtain aerogel-based photocatalytic materials with higher adsorptivity and photocatalytic activity, SiO2–W x TiO2 composite aerogels were synthesized by the method of combining freeze drying with solvothermal crystallization under the guidance of bacterial cellulose using BC–SiO2 composite gel as skeleton. The influences of W/Ti mol ratio, solvothermal process parameters on the microstructure and properties of the SiO2–W x TiO2 composite aerogels were investigated. The results indicate that the obtained composite aerogels have higher specific surface area with 297–377 m2 g−1 and pore volume with 0.46–0.66 cm3 g−1. The adsorption/photocatalysis test indicates that the obtained aerogels showed prominent adsorption/photocatalytic activity, and the adsorption/photocatalytic degradation rate for Rhodamine B in aqueous solution could attain to 95 % within 120 min, which is obviously better than that of P25. With the increase of solvothermal crystallization time, the adsorption/photocatalysis tends to increase and the SiO2–W x TiO2 composite aerogel sample exhibited better removing efficiency for Rhodamine B. Doping of 2–3% W is favorable for improving the adsorption/photocatalytic properties of the SiO2–W x TiO2 composite aerogels. The SiO2–W x TiO2 composite aerogels were synthesized by the method of combining freeze drying with solvothermal crystallization under the guidance of bacterial cellulose (BC). The presence and hydrolysis of BC as a template and inducer during the solvothermal process played an important role in enhancing the porous network structure of the composite aerogels and inducing the deposition/crystallization of W x TiO2 nanoparticles. The SiO2–W x TiO2 composite aerogels exhibited higher adsorptivity and photocatalytic activity simultaneously.

Lithium disilicate glass-ceramics were prepared with SiO2–Al2O3–Li2O–CeO2–P2O5-R2O as the base system through the traditional melting method and modified with K2O, Rb2O, Cs2O, and Tb4O7. The microstructure of the lithium disilicate glass-ceramics was characterized through differential thermal analysis, X-ray diffraction and scanning electron microscopy. The whiteness and fracture strength of the lithium disilicate glass-ceramics were investigated to validate their potential applications as dental materials. Results indicated that the mixed alkali effect exerted by the introduction of K2O, Rb2O, and Cs2O greatly improved the fracture strength of the modified lithium disilicate glass-ceramics. Furthermore, X-ray photoelectron spectroscopy and whiteness analysis proved that free oxygen increased through the introduction of larger alkali metal ions and terbium element in the glass-ceramics. The increase in free oxygen content through the introduction of Rb2O or Cs2O into the lithium disilicate glass-ceramics could effectively promote the formation of lithium disilicate crystals and the crystallization of lithium disilicate glass-ceramics. Research results indicated that lithium disilicate glass-ceramics with high fracture strength under pressureless sintering had been successfully fabricated.