Fabrication and characterization of photosensitive non-isocyanate polyurethane acrylate resin for 3D printing of customized biocompatible orthopedic surgical guides.

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 epidemiological survey of mental disorders 5 years after the Lushan earthquake in Ya'an, China.

PURPOSE: This study aimed to (1) explore the prevalence and relevant influencing factors of different mental disorders 5 years after the Lushan earthquake in Ya'an, China. METHODS: An epidemiological mental health survey was conducted to identify the prevalence of mental disorders in general population in Ya'an. A multi-stage, group-matching random sampling method was adopted. Face-to-face interviews were done with a two-stage design by trained interviewers and psychiatrists. The 5th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-V) was used for the diagnosis. RESULTS: There were 8876 participants who were interviewed in this study. The total 12-month and lifetime prevalence of all mental disorders were 12.5% and 14.7%, respectively. There was a significant difference between males and females in the prevalence patterns of several mental disorders. Han ethnic group had higher prevalence of anxiety disorders (2.7%), and the Tibetan group had higher prevalence of alcohol-related disorders (5.0%). Logistic regression analysis showed that the areas severely affected by the earthquake had significantly higher prevalence of depressive disorders, and the extremely severe affected areas had significantly higher prevalence of trauma- and stressor-related disorders. CONCLUSION: Our findings show that the prevalence of a range of mental disorders 5 years after the earthquake in Ya'an are high, and the prevalence of depressive and trauma- and stressor-related disorders may be influenced differently by the various severity of earthquake impact. This study may be crucial for the health policy-making, cultural-specific mental health services and long-term mental recovery after the earthquake.