Bladder cancer has become the most common malignant urinary carcinoma. Studies have shown that significant antioxidant and bladder cancer-fighting properties of several plant-based diets like Psidium guajava, ginger and amomum, are associated with their high kaempferol content. In this paper, we evaluated the antioxidant and anticancer activities of kaempferol and its mechanism of induction to apoptosis on bladder cancer cells. Our findings demonstrated that kaempferol showed an obvious radical scavenging activity in erythrocytes damaged by oxygen. Kaempferol promoted antioxidant enzymes, inhibited ROS generation and lipid peroxidation and finally prevented the occurrence of hemolysis. Additionally, kaempferol exhibited a strong inhibitory effect on bladder cancer cells and high safety on normal bladder cells. At the molecular level, kaempferol suppressed EJ bladder cancer cell proliferation by inhibiting the function of phosphorylated AKT (p-AKT), CyclinD1, CDK4, Bid, Mcl-1 and Bcl-xL, and promoting p-BRCA1, p-ATM, p53, p21, p38, Bax and Bid expression, and finally triggering apoptosis and S phase arrest. We found that Kaempferol exhibited strong anti-oxidant activity on erythrocyte and inhibitory effects on the growth of cancerous bladder cells through inducing apoptosis and S phase arrest. These findings suggested that kaempferol might be regarded as a bioactive food ingredient to prevent oxidative damage and treat bladder cancer.

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.

An amorphous precursor of Cr₂O₃ pigment was prepared via solution combustion synthesis. After calcination at 1000 °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.