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This review presents the recent advances and the current state-of-the-art of bioactive glass-based composite biomaterials intended for bone regeneration. Composite materials comprise two (or more) constituents at the nanometre scale, in which typically, one constituent is organic and functions as the matrix phase and the other constituent is inorganic and behaves as the reinforcing phase. Such materials, thereby, more closely resemble natural bio-nanocomposites such as bone. Various glass compositions in combination with a wide range of natural and synthetic polymers have been evaluated in vivo under experimental conditions ranging from unloaded critical-sized defects to mechanically-loaded, weight-bearing sites with highly favourable outcomes. Additional possibilities include controlled release of anti-osteoporotic drugs, ions, antibiotics, pro-angiogenic substances and pro-osteogenic substances. Histological and morphological evaluations suggest the formation of new, highly vascularised bone that displays signs of remodelling over time. With the possibility to tailor the mechanical and chemical properties through careful selection of individual components, as well as the overall geometry (from mesoporous particles and micro-/nanospheres to 3D scaffolds and coatings) through innovative manufacturing processes, such biomaterials present exciting new avenues for bone repair and regeneration.

Primary bone tumors especially, sarcomas affect adolescents the most because it originates from osteoblasts cells responsible for bone growth. Chemotherapy, surgery, and radiation therapy are the most often used clinical treatments. Regrettably, surgical resection frequently fails to entirely eradicate the tumor, which is the primary cause of metastasis and postoperative recurrence, leading to a high death rate. Additionally, bone tumors frequently penetrate significant regions of bone, rendering them incapable of self-repair, and impairing patients' quality of life. As a result, treating bone tumors and regenerating bone in the clinic is difficult. In recent decades, numerous sorts of alternative therapy approaches have been investigated due to a lack of approved treatments. Among the novel therapeutic approaches, hydrogel-based anticancer therapy has cleared the way for the development of new targeted techniques for treating bone cancer and bone regeneration. They include strategies such as co-delivery of several drug payloads, enhancing their biodistribution and transport capabilities, normalizing accumulation, and optimizing drug release profiles to decrease the limitations of current therapy. This review discusses current advances in functionalized hydrogels to develop a new technique for treating bone tumors by reducing postoperative tumor recurrence and promoting tissue repair.

Osteosarcoma (OS) is one of the most common primary bone malignancies in children and adolescents. The toxicity to healthy tissues from conventional therapeutic strategies, including chemotherapy and radiotherapy, and drug resistance, severely affects OS patients' quality of life and cancer-specific outcomes. Many efforts have been made to develop various nanomaterial-based drug delivery systems with specific properties to overcome these limitations. Among the developed nanocarriers, liposomes are the most successful and promising candidates for providing targeted tumour therapy and enhancing the safety and therapeutic effect of encapsulated agents. Liposomes have low immunogenicity, high biocompatibility, prolonged half-life, active group protection, cell-like membrane structure, safety and effectiveness. This review will discuss various nanomaterial-based carriers in cancer therapy and then the characteristics and design of liposomes with a particular focus on the targeting feature. We will also summarise the recent advances in the liposomal drug delivery system for OS treatment in preclinical and clinical studies.

There has been a rapid increase in bone tissue regeneration since the concept of "tissue engineering." Stem cell-based biomaterials have revolutionized the field of tissue regeneration. Biomaterials play an essential part in bone regeneration through their crucial substratum for cell differentiation, cohesion, and proliferation by manipulating cells. Numerous studies have been carried out in order to create a biomaterial with diverse biological and physical characteristics. Furthermore, they developed a cell microenvironment with the desired pore magnitude to stimulate stem cells to transform them from artificial to biological microenvironments.The current review aims to give a comprehensive overview of stem cells and biomaterials in bone tissue regeneration.Initially, bone biology and its interaction with stem cells and biomaterials are briefly explained. Following that, the behavior and mechanism of biomaterials influencing the stem cells during bone tissue regeneration are emphasized. Lastly, the future outlook for tackling the current challenges for designing biomaterials/stem cell materials for bone tissue engineering (TE) is discussed.Compatible biomaterial for bone regeneration requires evaluating the structure, matrix, composition, flexibility, and nature of native bone tissue defects. The concept of TE offers a platform for designing biologically, physically, and chemically biocompatible biomaterials for stem cells to proliferate and differentiate. Currently, stem cells are increasingly used for TE with a promising outcome due to their self-renewal and differentiation potential. Furthermore, they can secrete biological-active compounds and modulate the fate and behavior of other cells in native tissues. Bone TE may flourish more rapidly and efficiently using stem cells.

Background Hypermethylation of gene promoters has been regarded as an epigenetic regulator for gene inactivation in the development of several diseases. In the current study, we aimed to explore how long noncoding RNA X-inactive specific transcript (lncRNA XIST) function in collagen degradation in chondrocytes of osteoarthritis (OA) after tibial plateau fracture by regulating tissue inhibitor of metalloproteinase-3 (TIMP-3) promoter methylation. Methods In silico analysis was used to screen differentially expressed lncRNAs in cartilage tissues of OA. Chondrocytes were then successfully isolated from normal and OA cartilage tissues and identified, with the expressions of lncRNA XIST and TIMP-3 examined. The methylation levels of TIMP-3 promoter were determined by MS-PCR. The binding of lncRNA XIST to DNA methyltransferase and the binding of TIMP-3 promoter to DNA methyltransferase were determined by a series of experiments, including RIP, RNA pull-down, and ChIP assays. Results The differentially expressed lncRNA XIST was determined in OA. In addition, cartilage tissues of OA showed upregulation of lncRNA XIST and downregulation of TIMP-3. LncRNA XIST was primarily localized in the nucleus and was capable of binding to the promoter of TIMP-3. The silencing of lncRNA XIST decreased the methylation levels of TIMP-3 promoter and increased the expressions of TIMP-3, which consequently inhibited collagen degradation in OA chondrocytes. Furthermore, TIMP-3 over-expression reversed the effect of lncRNA XIST on collagen degradation in OA chondrocytes. Conclusion Collectively, lncRNA XIST raises collagen degradation in OA chondrocytes after tibial plateau fracture by accelerating the methylation of TIMP-3 promoter by recruiting DNA methyltransferase.

A new two-stage gasification process, decoupling complex biomass gasification from biomass pyrolysis and char gasification, has been proposed for the production of clean industrial fuel gas. In this work, Chinese herb residues will be used as raw material, and the fundamental studies and demonstration of this process were conducted on an externally heated laboratory two-stage gasification setup and an industrial demonstration plant, respectively. The fundamental studies found that the appropriate operation of the upstream fluidized bed (FB) pyrolyzer occurred at 700 °C and the suitable conditions for effective tar removal in the downstream gasifier were as follows: 850 °C, an equivalent ratio of air (ER) at 0.04, and a retention time of tar-containing fuel gas above 0.9 s. On the basis of these fundamental data, an autothermal demonstration plant treating 600 kg of herb residue per hour was built and successfully commissioned for its continuous running to verify the technology feasibility. The running dat...

A fluidized bed two-stage gasification process, consisting of a fluidized-bed (FB) pyrolyzer and a transport fluidized bed (TFB) gasifier, has been proposed to gasify biomass for fuel gas production with low tar content. On the basis of our previous fundamental study, an autothermal two-stage gasifier has been designed and built for gasify a kind of Chinese herb residue with a treating capacity of 600 kg/h. The testing data in the operational stable stage of the industrial demonstration plant showed that when keeping the reaction temperatures of pyrolyzer and gasifier respectively at about 700 degrees C and 850 degrees C, the heating value of fuel gas can reach 1200 kcal/Nm3, and the tar content in the produced fuel gas was about 0.4 g/Nm(3). The results from this pilot industrial demonstration plant fully verified the feasibility and technical features of the proposed FB two-stage gasification process. (C) 2016 Published by Elsevier Ltd.

The so-called micro fluidized bed reaction analyzer (MFBRA) was adopted to implement the isothermal gasification of in situ coal char with CO2 under minimized external diffusion inhibition. It was done by keeping the reaction atmosphere and temperature in the MFBRA for both coal pyrolysis and char gasification. This was further compared to the gasification of two other kinds of ex situ chars. While the gasification of ex situ char 1 referred to the coal pyrolysis in Ar and then CO2 gasification of the resulting hot char without thermal annealing (cooling) in the same MFBRA, that of the ex situ char 2 was by first a separate coal pyrolysis in Ar and then gasification of the char in the MFBRA after thermal annealing (cooling). Reaction characterization and kinetic parameters based on the measured time-series product gas composition of CO clarified that the in situ coal char had the highest gasification reactivity and the lowest activation energy, whereas the ex situ coal char 2 showed the lowest gasification reactivity and the highest activation energy. Comparing the gasification behavior of chars made with Yima (YM) bituminous coal and Xilinhaote (XLHT) lignite further demonstrated that the char of XLHT lignite had the higher reactivity and smaller activation energy, complying with the higher gasification activity of lignite char than that of bituminite char.

A novel Ag3PO4/Nb2O5 fiber composite was fabricated through depositing Ag3PO4 nanoparticles on Nb2O5 fiber surfaces through a facile depositing precipitation approach. The as-prepared Ag3PO4/Nb2O5 photocatalyst was characterized through XRD, SEM, XPS and UV-Vis measurements. SEM results show that biomorphic Nb2O5 fibers have a wrinkled surface and porous walls. The special morphology of the Nb2O5 fibers provided a large amount of voids and interfaces in favor of decorating with Ag3PO4 nanocrystals. The Ag3PO4/Nb2O5 composite photocatalyst exhibits much higher photocatalytic activity for the degradation of rhodamine B than pure Ag3PO4 under simulated sunlight. Such superior photocatalytic activity is mainly attributed to enhanced visible light absorption and effective separation of photogenerated electron–hole pairs derived from the Ag3PO4/Nb2O5 heterojunction. No loss of photocatalytic activity has been observed after four recycles. Moreover, the large size of the Ag3PO4/Nb2O5 composite allows it to be easily separated from the solution.

Visible light driven BiOBr/rod-like BiPO4 composites with different BiOBr to BiPO4 molar ratios were fabricated via a facile deposition-precipitation method. X-ray powder diffraction, field emission scanning electron microscopy, transmission electron microscopy, UV-Vis diffuse reflectance spectroscopy and Brunauer–Emmett–Teller surface area were used to characterize the as-synthesized samples. Results showed that the BiOBr/rod-like BiPO4 composite with equal mole ratio exhibited the best photocatalytic performance for rhodamine B (RhB) degradation under visible light irradiation. The enhanced photocatalytic performance could be mainly attributed to the effective separation of the photogenerated electrons and holes at the heterojunction interface of p-BiOBr and n-BiPO4.

Cotton was used as template for the fabrication of a biomorphic Nb2O5 photocatalyst with hexagonal and orthorhombic structures. The as-prepared Nb2O5 was characterized through X-ray diffraction (XRD), scanning electron microscopy (SEM), specific surface area and UV-Vis diffused reflectance spectra measurements. The photocatalytic activity of the Nb2O5 fibers was evaluated through degradation of methylene blue (MB) in aqueous solution exposed to UV light. SEM results show that biomorphic Nb2O5 fibers are both hollow and have porous walls. The architectures allow a more accessible surface for the photocatalytic decomposition of dyes molecules. The photocatalytic activity of physically mixed fibers with 75% H-Nb2O5 and 25% O-Nb2O5 phases is superior to those of pure H- and O-Nb2O5 phases, and other samples with different H- and O-Nb2O5 ratios. Such superior photocatalytic activity is mainly due to an optimal balance between the adsorption of MB and the absorption of UV light. Moreover, the large size of the Nb2O5 hollow fibers allows them to be easily separated from the solution.