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Three-dimensional (3D)-printed orthopedic surgical guides have the potential to provide personalized precision treatment. Non-isocyanate polyurethane (NIPU) is commonly used in the 3D printing of biomedical materials but its application in the orthopedic surgical guide is limited by poor mechanical properties and biocompatibility. In this study, we fabricated non-isocyanate polyurethane acrylate (NIPUA) photosensitive resin with superior biocompatibility and mechanical properties required for 3D-printed orthopedic surgical guides. NIPU prepolymer was synthesized by a ring-opening reaction and a ring acrylation reaction. NIPUA was further synthesized using polyethylene glycol diacrylate (PEGDA) as a modified material based on sustainable synthesis with reduced synthesis time. NIPUA showed the best tensile and flexural strengths when the PEGDA content reached 12 wt.%. NIPUA exhibited higher thermal stability, hemocompatibility, superior biocompatibility to ME3T3-E1 bone cells and C1C12 muscle cells, and non-immunogenic effect toward macrophages compared with commercial photosensitive resins. Commercial resins triggered a severe inflammatory response during in vivo implantation, but this effect was not observed during NIPUA implantation. Transcriptome analysis showed downregulation of cell death and cell cycle disruption-related genes, such as CDK2, CDKN1a, and GADD45a, and upregulation of autophagy and anti-tumor activity-related genes, such as MYC, PLK1, and BUB1b, in NIPUA-treated MC3T3-E1 cells compared with commercial resin-treated MC3T3-E1 cells. In conclusion, NIPUA resin showed excellent mechanical and thermal properties as well as good biocompatibility toward bone cells, muscle cells, and macrophages, suggesting its possible application in the 3D printing of customized orthopedic surgical guides.

Porous scaffolds as succedaneum of natural bone were investigated and applied in medical field. In this work, we carried out studies on mechanical properties of solid parts and porous scaffolds obtained by additive manufacturing (AM) technique. It is found that productions of AM process have a higher yield strength and higher microhardness compared to commercial Ti6Al4V. Roughened surface was observed for layer-by-layer process of AM and sticking of powder particles. The machining accuracy is affected by both dimensions and angles. Meanwhile, mechanical properties of porous scaffolds are influenced by machining accuracy and microdefects. In addition, the unit cell structures also impact the mechanical properties of porous scaffolds in terms of elastic modulus, yield strength and failure mode. Overall, considering the mechanical properties and biological properties, scaffolds with cube (CB) crystal cells are the best choice in our study.

An amorphous precursor of Cr2O3 pigment was prepared via solution combustion synthesis. After calcination at 1000 &deg, C for 1.0 h, the precursor was converted into well-crystallized submicron Cr2O3 crystals with uniform particle distribution and low aggregation. Furthermore, Ti, Co, and Fe were doped into the lattice of Cr2O3, and the effects of these dopants on the reflectance spectroscopy modulation as well as chromatic properties were investigated in detail. As a result, a series of Cr2O3 pigment samples sharing similar spectra within the wavelength from 400 to 1600 nm with green plants could be successfully fabricated.

In recent years, photothermal materials have attracted much attention in cancer research. In the present study, a new near infrared biocompatible photothermal therapeutic (PTT) agent, named BPD-BBTD was synthesized by the facile one-step Suzuki reaction. This agent has excellent proterties, such as high photothermal conversion efficiency (40 %), photothermal cycle stability, and even can withstand superacid and superalkali environments. More importantly, a new type of photo thermal gel BPD-BBTD-NPs@PDA-PAM hydrogels was synthesized. The hydrogels have not only excellent anti stretching, biocompatibility, exceedingly and adhesion, but also excellent photothermal transformation ability. The temperature of the hydrogels are up to 102 °C under 0.8 W cm−2 808 nm laser irradiation for 4 min, which is higher than most reported inorganic and organic PTT agents. In vitro experiments showed that BPD-BBTD-NPs@PDA-PAM hydrogels exhibited excellent photothermal killing ability for cancer cells under low power laser irradiation (0.3 W cm−2). This work can not only contribute to enrich the research of photothermal therapy, but also has potential usage in photothermal treatment of breast cancer.

To improve biocompatibility and mechanical compatibility, post-treatment is necessary for porous scaffolds of bone tissue engineering. Hot isostatic pressing (HIP) is introduced into post-treatment of metal implants to enhance their mechanical properties by eliminating residual stress and pores. Additionally, oxide film formed on the material surface can be contributed to improve its biocompatibility. Ti6Al4V porous scaffolds fabricated by laser-powder bed fusion (L-PBF) process is studied in this paper, their mechanical properties are measured by pressure test, and the macroscopic surface morphology and microstructure are observed by optical microscope (OM), scanning electron microscope (SEM) and transmission electron microscope (TEM). After HIP treatment, an oxide layer of 0.8 &mu, m thickness forms on the surface of Ti6Al4V porous scaffolds and the microstructure of Ti6Al4V transforms from &rsquo, phase to  dual-phase, as expected. However, the pressure test results of Ti6Al4V porous scaffolds show a definitely different variation trend of mechanical properties from solid parts, unexpectedly. Concerning Ti6Al4V porous scaffolds, the compression stiffness and critical stress improves clearly using HIP treatment, and the fracture morphology shows obvious brittle fracture. Both the strengthening and brittleness transition of Ti6Al4V porous scaffolds result from the formation of an oxide layer and an oxygen atom diffusion layer. The critical stress of Ti6Al4V porous scaffolds can be calculated by fully considering these two strengthening layers. To obtain a porous scaffold with specific mechanical properties, the effect of post-treatment should be considered during structural design.

P-element-induced wimpy testis (PIWI)-interacting RNAs (piRNAs), a novel class of noncoding RNAs, are involved in the carcinogenesis. However, the functional significance of piRNAs in oral squamous cell carcinoma (OSCC) remains unknown. In the present study, we used chemical carcinogen 4-nitroquinoline-1-oxide (4NQO) induced OSCC mouse model. piRNAs and mRNAs were profiled using next-generation sequencing in the tongue tumor tissues from 4NQO induction and healthy tongue tissues from control mice. Furthermore, we analyzed the differential gene expression of human OSCC in Gene Expression Omnibus (GEO) database. According to the common differentially expressed genes in the 4NQO model and human OSCC tissues, piRNAs and mRNAs network were established based on informatics method. A total of 14 known piRNAs and 435 novel predicted piRNAs were differently expressed in tumor tissue compared to healthy tissue. Among differently expressed piRNAs 260 were downregulated, and 189 were upregulated. The mRNA targets for the differentially expressed piRNAs were identified using RNAhybrid software. Primary immunodeficiency and herpes simplex infection were the most enriched pathways. A total of 22 mRNAs overlapped in human and mice OSCC. Moreover, we established the regulatory network of 11 mRNAs, including Tmc5, Galnt6, Spedf, Mybl2, Muc5b, Six31, Pigr, Lamc2, Mmp13, Mal, and Mamdc2, and 11 novel piRNAs. Our data showed the interaction between piRNAs and mRNAs in OSCC, which might provide new insights in the development of diagnostic biomarkers and therapeutic targets of OSCC.

A novel MIL-68(In)-NH 2 /graphene oxide (GrO) composite was prepared as a visible-light-driven photocatalyst for the degradation of amoxicillin (AMX). The MIL-68(In)-NH 2 /GrO composite exhibited much higher photocatalytic activity than pure MIL-68(In)-NH 2 . Using 0.6 g L −1 MIL-68(In)-NH 2 /GrO and pH = 5, 93% degradation and 80% TOC removal toward AMX could be achieved after irradiation time of 120 and 210 min, respectively. The enhanced activity for MIL-68(In)-NH 2 /GrO can be attributed to the modification by using GrO, which not only acted as electron transporters for suppressing the photogenerated carrier recombination, but also played as a sensitizer for enhancing visible light absorption. Further experiments revealed that the solution pH had a significant impact on the photodegradation of AMX. In addition, MIL-68(In)-NH 2 /GrO possessed good reusability and stability. Finally, the enhanced photocatalytic mechanism over MIL-68(In)-NH 2 /GrO was also proposed, and h + and O 2 − were further determined to be the main active species in the photocatalytic system.

15,16-Dihydrotanshinone I (DI), a natural compound isolated from a traditional Asian functional food Salvia Miltiorrhiza Bunge, is known for its anticancer activity. However, poor solubility of DI limits its desirable anticancer application. Herein, polylactic- co-glycolic acid (PLGA) was functionalized with polyethylene glycol (PEG) and biotin to form copolymers PEG-PLGA (PPA) and biotin-PEG-PLGA (BPA). DI was encapsulated in copolymers PPA and BPA to obtain DI-PPA-NPs (NPs = nanoparticles) and DI-BPA-NPs, respectively. The particle size and its distribution, encapsulation efficiency, and in vitro releasing capacity of DI-BPA-NPs were characterized by biophysical methods. MTT assay was used to evaluate the antiproliferative activity of free DI, DI-PPA-NPs, and DI-BPA-NPs in human cervical cancer Hela cells. DI-BPA-NPs showed the highest cytotoxicity on Hela cells with an IC50 value of 4.55 ± 0.631 μM, while it was 8.20 ± 0.849 and 6.14 ± 0.312 μM for DI and DI-PPA-NPs in 72 h, respectively. The superior antiproliferative activity was supported by the fact that DI-BPA-NPs could be preferentially internalized by Hela cells, owing to their specific interaction between biotin and overexpressed biotin receptors. In addition, DI-BPA-NPs effectively inhibited Hela cell proliferation by inducing G2/M phase cycle arrest and decreasing the intracellular reactive oxygen species (ROS) level by 31.50 ± 2.29% in 5 min. In summary, DI-BPA-NPs shows improved antiproliferative activity against human cervical cancer as comparing with free DI, demonstrating its application potential in cancer therapy.

Calcium phosphate layers, which are widely applied on the surface of biomaterials, are important for improving tissue regeneration performance. The composition of layers formed on the surface of biomaterials differs depending on the soaking fluid. Herein, revised simulated blood fluid and fast calcification solution were investigated as immersing solutions for the mineralization of hydroxyapatite ceramics. The morphology of the hydroxyapatite particles and precipitate formation on the hydroxyapatite ceramics surface were characterized by transmission electron microscopy. Furthermore, scanning electron microscopy was used to examine the morphology of the bioactive ceramics surface. The structure of the layers was determined by selected-area electron diffraction. The prepared hydroxyapatite powders were characterized by powder X-ray diffraction. The results showed that hydroxyapatite was preferentially formed on the hydroxyapatite ceramics surface in revised simulated blood fluid and octacalcium phosphate precipitated in fast calcification solution. Additionally, the content of HCO3- in the mineralization fluid strongly influenced the crystal phase composition and morphology of the calcium phosphate layers on the bio-ceramics materials studied herein.

Beta-tricalcium phosphate (β-TCP) nanocoatings, which can be analysed using a quartz crystal microbalance with dissipation technique (QCM-D), were fabricated on a gold surface by electrophoretic deposition. The influences of electric field intensity and electrophoresis time were investigated. The adsorption behaviours of bovine serum albumin (BSA) and lysozyme (LSZ) on Au and β-TCP surfaces were observed in real time by QCM-D. The homogeneous β-TCP nanocoating with moderately sized particles on gold surface was fabricated at 25V/cm for 5min, and it met the requirements for the QCM-D experiment. The adsorption behaviour of BSA was different from that of LSZ, which was caused by the differences of protein properties. The adsorption quantity of BSA on a β-TCP surface was higher than that on a gold surface. However, the adsorption amount of LSZ on a β-TCP surface was lower than that on a gold surface. The electrostatic force was the major factor affecting the adsorption quantities of BSA and LSZ on Au and β-TCP surfaces based on the investigation of various factors. The findings reported here will be useful for understanding the mechanism of the interaction between biomaterials and proteins.

In this report, we present results from our experiments on composite coatings formed on biomedical titanium substrates by micro-arc oxidation (MAO) in constant-voltage mode. The coatings were prepared on the substrates in an aqueous electrolyte containing calcium acetate and β-glycerol phosphate disodium salt pentahydrate (β-GP). We analyzed the element distribution and phase components of the coatings prepared at different voltages by X-ray diffraction, thin-coating X-ray diffraction, electron-probe microanalysis, and Fourier-transform infrared spectroscopy. The results show that the composite coatings formed at 500 V consist of titania (TiO2), hydroxylapatite (HA), and calcium carbonate (CaCO3). Furthermore, the concentration of Ca, P, and Ti gradually changes with increasing applied voltage, and the phase components of the composite coatings gradually change from the bottom of the coating to the top: the bottom layer consists of TiO2, the middle layer consists of TiO2 and HA, and the top layer consists of HA and a small amount of CaCO3. The formation of HA directly on the coating surface by MAO technique can greatly enhance the surface bioactivity.

In this paper, we present the first report about constructing a scaffold-like delivery system with poly (lactic-co-glycolic) (PLGA) microspheres on micro-arc oxidation titanium (MAO-Ti). The results show that this system could be stable on the porous MAO-Ti surface up for 6 weeks. Not only the system could control the release of model protein BSA, but also the MAO film could regulate the pH value of the solution which would decrease by the degradation of PLGA microspheres. In addition, compared to MAO-Ti, this system loaded with BSA could improve the proliferation of HBMSCs after 3 or 7 days culture.

Whereas TNF-α can facilitate the metastasis of oral squamous cancer cells (OSCC), whether it inhibits the metastasis is not clear so far. In this study, we demonstrated that high dose TNF-α at 100ng/mL could in vitro significantly inhibit the migration of two OSCC cell lines, CAL-27 and SCC-25. To explore the related mechanisms, we focused on the involvement of the microRNAs and found that TNF-α increased the expression of miR-765. The upregulation of miR-765 was attributed to the inhibition of the migration. We showed that miR-765 directly targeted EMP3 and suppressed its expression. We also found that the expression of EMP3 was much higher in human oral squamous cancer in compare with the surrounding normal tissue. Interestingly, p66Shc, a downstream molecule in the EMP3-related signaling pathway, was increased by TNF-α. We found that the overexpression of p66Shc could suppress the migration through the enhanced E-cadherin and ZO-1 signals. Either silencing the expression of EMP3 or enhancing the expression of miR-765 could upregulate the expression of p66Shc. Together, our results demonstrated that TNF-α inhibited the metastasis of oral squamous cancer cell through the miR-765-EMP3-p66Shc axis, which may provide new insights for the therapy of oral squamous cancer.

The Ca- and P-containing MAO films were prepared on titanium substrate at different frequencies (100–5000 Hz) and were characterized by SEM, XRD, XPS and contact angle goniometer. For in vitro test, the rat bone marrow mesenchymal stem cells (rMSCs) were seeded on the films. The fluorescence microscopy and the PicoGreen assay were used to determine the cell initial adhesion and proliferation. It shows that the frequency of the MAO affected the crystallinity, composition, morphology and wetting ability of the oxidation film. At a high frequency, the crystallinity decreased, and the content of Ca and P increased. The structure formed at a high frequency – there were many smaller pores on the wall of the larger ones and many inner pores in the film – could improve the connectivity of the film. The wetting ability of the film was also improved by increasing the frequency. The mechanism of how the frequency of the MAO process could influence the oxidation film was discussed. It could be explained by the theory of electron avalanche and the phenomenon of secondary breakdown. In vitro test showed that the film formed at 5000 Hz was more favorable for the initial cell attachment and proliferation.

Porous polycaprolactone (PCL) scaffolds were fabricated by combination of porogen-leaching and freeze-drying processes. Ice particulates were used as porogen materials. The porous PCL scaffolds were modified by potassium hydroxide solution with concentration of 1 mol/L at room temperature for 8 h, subsequently biomineralized in simulated body fluid for 2 h and 8 h, respectively. The microstructure and characteristics of the PCL scaffolds were investigated by scanning electron microscope (SEM) and EDS. The results showed (1) PCL scaffolds had high degree of connectivity and different pore sizes. (2) Plate-like apatite was observed on the surface of the scaffolds after being immersed into SBF for 8 h.

In the present study, porous PCL (poly (epsilon-caprolactone)) scaffolds were prepared through a melted extrusion manufacturing (MEM) machine, and carboxylate groups were formed on the surfaces of specimen by hydrolyzation with NaOH aqueous solutions. Apatite precursor was introduced on the surfaces of specimens with CaCl2 and K2 HPO4 under vacuum condition, and mineralization study was applied to these specimens. The results showed that the hydrophilicity of PCL surface was improved with the introduction of carboxylate groups, and the contact angle of surface was decreased to 26.52 degrees. A dense and uniform bone-like layer was confirmed to be formed on the surface of Ca-P treated specimens after mineralizing for less than 24 h in SBF by SEM and EDAX.