Fabrication and in vitro evaluation of 3D printed porous silicate substituted calcium phosphate scaffolds for bone tissue engineering.

Silicate-substituted calcium phosphate (Si-CaP) ceramics, alternative materials for autogenous bone grafting, exhibit excellent osteoinductivity, osteoconductivity, biocompatibility, and biodegradability; thus, they have been widely used for treating bone defects. However, the limited control over the spatial structure and weak mechanical properties of conventional Si-CaP ceramics hinder their wide application. Here, we used digital light processing (DLP) printing technology to fabricate a novel porous 3D printed Si-CaP scaffold to enhance the scaffold properties. Scanning electron microscopy, compression tests, and computational fluid dynamics simulations of the 3D printed Si-CaP scaffolds revealed a uniform spatial structure, appropriate mechanical properties, and effective interior permeability. Furthermore, compared to Si-CaP groups, 3D printed Si-CaP groups exhibited sustained release of silicon (Si), calcium (Ca), and phosphorus (P) ions. Furthermore, 3D printed Si-CaP groups had more comprehensive and persistent osteogenic effects due to increased osteogenic factor expression and calcium deposition. Our results show that the 3D printed Si-CaP scaffold successfully improved bone marrow mesenchymal stem cells (BMSCs) adhesion, proliferation, and osteogenic differentiation and possessed a distinct apatite mineralization ability. Overall, with the help of DLP printing technology, Si-CaP ceramic materials facilitate the fabrication of ideal bone tissue engineering scaffolds with essential elements, providing a promising approach for bone regeneration.

Low-level laser therapy with different irradiation methods modulated the response of bone marrow mesenchymal stem cells in vitro.

Low-level laser therapy (LLLT) also known as photobiomodulation is a treatment to change cellular biological activity. The exact effects of LLLT remain unclear due to the different irradiation protocols. The purpose of this study was to investigate the effects of LLLT by three different irradiation methods on the proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) in vitro. BMSCs were inoculated in 24-well plates and then irradiated or not (control) with a laser using three different irradiation methods. The irradiation methods were spot irradiation, covering irradiation, and scanning irradiation according to different spot areas (0.07 cm2 or 1.96 cm2) and irradiation areas (0.35 cm2 or 1.96 cm2), respectively. The laser was applied three times at energy densities of 4 J/cm2. The cell proliferation by CCK-8. ALP activity assay, alizarin red, and quantitative real-time polymerase chain reaction (RT-PCR) were performed to assess osteogenic differentiation and mineralization. Increases in cell proliferation was obvious following irradiation, especially for covering irradiation. The ALP activity was significantly increased in irradiated groups compared with non-irradiated control. The level of mineralization was obviously improved following irradiation, particularly for covering irradiation. RT-PCR detected significantly higher expression of ALP, OPN, OCN, and RUNX-2 in the group covering than in the others, and control is the lowest. The presented results indicate that the biostimulative effects of LLLT on BMSCs was influenced by t he irradiation method, and the covering irradiation is more favorable method to promote the proliferation and osteogenic differentiation of BMSCs.

Factors influencing bedtime procrastination in junior college nursing students: a cross-sectional study.

BACKGROUND: Sleep quality is related to physical and mental health. Though bedtime procrastination has been identified as a potentially key source of poor sleep quality, related research is scarce. The goal of our study was to determine bedtime procrastination among nursing students and identify its influencing factors. METHODS: This cross-sectional study comprised 1827 junior college nursing students. The data were collected from November to December 2021 using a mobile app-based survey. We evaluated demographic factors, Big Five personality traits, self-regulatory fatigue, future time perspective, and problematic mobile phone use. Multiple linear regression analysis was used to identify independent characteristics that influence bedtime procrastination among junior college nursing students. RESULTS: The mean bedtime procrastination score in junior college nursing students was 25.11 ± 6.88. Family monthly income of 3000-6000 RMB (ß = 0.740; p = 0.015), as well as that of > 6000 RMB (ß = 1.708; p = 0.001), and an extroverted personality (ß = 0.225; p = 0.001), self-regulatory fatigue (ß = 0.135; p < 0.001), and problematic mobile phone use (ß = 0.078; p < 0.001) had significant positive effects on bedtime procrastination. Conscientious personality (ß = - 0.284; p = 0.003), neurotic personality (ß = - 0.203; p = 0.031), and future time perspective (ß = - 0.141; p < 0.001) had significant negative effects on bedtime procrastination. CONCLUSION: The nursing students who participated in this study had moderate levels of bedtime procrastination. Bedtime procrastination was predicted by higher monthly household income; personality traits of extroversion, conscientiousness, and neuroticism; self-regulatory fatigue; future time perspective; and problematic mobile phone use. PRACTICAL IMPLICATIONS: We recommend that effective measures are needed to help alleviate bedtime procrastination and improve the health and well-being of nursing students.

Trephine-based foraminoplasty in PTED treatment of lumbar lateral recess stenosis.

BACKGROUND: During minimally invasive spine surgery, nerve root decompression is challenging due to the anatomical division and uncertainty in lumbar lateral recess (LLR). OBJECTIVES: To evaluate the outcome and safety of foraminoplasty using percutaneous transforaminal endoscopic decompression (PTED) (performed with an aid of a trephine) in the treatment of lumbar lateral recess stenosis (LLRS). MATERIAL AND METHODS: All operations were performed under local anesthesia and in prone position. The puncture point was 10-14 cm away from the midline of the spinous process. One hundred eight individuals with LLRS who underwent PTED from September 2016 to December 2020 in our hospital were enrolled in the study. Visual Analog Scale (VAS) and Oswestry Disability Index (ODI) scores were collected preoperatively after 1 day, 7 days, 1 month and at the final follow-up (June 2021). Low back pain and leg pain were measured using VAS score. Functional outcomes were assessed with ODI and modified Macnab criteria. RESULTS: After the surgery, the VAS score and ODI were statistically significant at all follow-up points compared with the pre-surgery (both p < 0.05). Based on the modified Macnab scores at the final follow-up, the satisfaction rate at postoperative 1 month was 96.3% and the satisfaction rate at postoperative 7 days was 70.38%. A significant difference was observed between the 2 groups (p < 0.05). CONCLUSIONS: Foraminoplasty using PTED performed with a trephine is one of the safe and effective, minimally invasive methods to treat LLRS.