Self-cleaning poly(dimethylsiloxane) film with functional micro/nano hierarchical structures.

This paper reports a novel single-step wafer-level fabrication of superhydrophobic micro/nano dual-scale (MNDS) poly(dimethylsiloxane) (PDMS) films. The MNDS PDMS films were replicated directly from an ultralow-surface-energy silicon substrate at high temperature without any surfactant coating, achieving high precision. An improved deep reactive ion etching (DRIE) process with enhanced passivation steps was proposed to easily realize the ultralow-surface-energy MNDS silicon substrate and also utilized as a post-treatment process to strengthen the hydrophobicity of the MNDS PDMS film. The chemical modification of this enhanced passivation step to the surface energy has been studied by density functional theory, which is also the first investigation of C4F8 plasma treatment at molecular level by using first-principle calculations. From the results of a systematic study on the effect of key process parameters (i.e., baking temperature and time) on PDMS replication, insight into the interaction of hierarchical multiscale structures of polymeric materials during the micro/nano integrated fabrication process is experimentally obtained for the first time. Finite element simulation has been employed to illustrate this new phenomenon. Additionally, hierarchical PDMS pyramid arrays and V-shaped grooves have been developed and are intended for applications as functional structures for a light-absorption coating layer and directional transport of liquid droplets, respectively. This stable, self-cleaning PDMS film with functional micro/nano hierarchical structures, which is fabricated through a wafer-level single-step fabrication process using a reusable silicon mold, shows attractive potential for future applications in micro/nanodevices, especially in micro/nanofluidics.

Clinical trials using dental stem cells: 2022 update.

For nearly 20 years, dental stem cells (DSCs) have been successfully isolated from mature/immature teeth and surrounding tissue, including dental pulp of permanent teeth and exfoliated deciduous teeth, periodontal ligaments, dental follicles, and gingival and apical papilla. They have several properties (such as self-renewal, multidirectional differentiation, and immunomodulation) and exhibit enormous potential for clinical applications. To date, many clinical articles and clinical trials using DSCs have reported the treatment of pulpitis, periapical lesions, periodontitis, cleft lip and palate, acute ischemic stroke, and so on, and DSC-based therapies obtained satisfactory effects in most clinical trials. In these studies, no adverse events were reported, which suggested the safety of DSC-based therapy. In this review, we outline the characteristics of DSCs and summarize clinical trials and their safety as DSC-based therapies. Meanwhile, we also present the current limitations and perspectives of DSC-based therapy (such as harvesting DSCs from inflamed tissue, applying DSC-conditioned medium/DSC-derived extracellular vesicles, and expanding-free strategies) to provide a theoretical basis for their clinical applications.

Protective effects of silibinin on LPS-induced inflammation in human periodontal ligament cells.

Clinically, periodontitis is a chronic nonspecific inflammation that leads to damaged teeth and their supporting gum tissues. Although many studies on periodontitis have been conducted, therapy with natural products is still rare. Silibinin has been proven to have anti-inflammatory and antioxidant activities. However, the effects of silibinin on lipopolyssacharide (LPS)-induced inflammation in periodontal ligaments (PDLs) have not yet been investigated. In this study, the PDLs were treated with silibinin (10, 20, and 40 µM) in the presence of LPS. The results showed that silibinin treatment reduced the levels of NO, PGE2, IL-6, TNF-α, MMP-1, and MMP-3 and enhanced the activities of superoxide dismutase (SOD) and glutathione (GSH). Moreover, silibinin treatment downregulated RANKL levels and upregulated OPG and ALP levels. In summary, silibinin protected PDLs against LPS-induced inflammation, oxidative stress, and osteogenic differentiation.

Combined Application of Grid Body Surface Locator and Preemptive Analgesia in Daytime Vertebroplasty.

Objective: To explore the clinical advantages of grid body surface locator combined with preemptive analgesia in the treatment of osteoporotic lumbar fractures in daytime vertebroplasty. Methods: A retrospective study was conducted on 120 patients who underwent lumbar vertebroplasty in the Department of Orthopedics of General Hospital of Northern Theater Command from January 2017 to January 2020. According to the preoperative planning and analgesic mode of treatment, they were divided into the daily operation experimental group and the traditional mode control group. Prone positioning of a patient under anesthetic is safe of ensuring optimum surgical access for many procedures, providing that the risks are fully understood. The general baseline data, intraoperative fluoroscopy times and operation time, bone cement injection volume, bone cement permeability, VAS score before operation, 1 day, and 3 months after operation, and the recovery of anterior vertebral height before and after operation were analyzed. Results: There was no statistically significant difference in the preoperative general data between the two groups. One day after operation, the VAS score of the experimental group was lower than that of the control group, but there was no difference after 3 months. The permeability of bone cement in the experimental group was lower than that in the control group, the height of anterior edge of injured vertebra was better than that in the control group, and the operation time was less than that in the control group. Conclusion: The daytime operation experimental group can significantly alleviate postoperative pain, increase the amount of bone cement injection, and reduce the permeability of bone cement through preoperative planning of puncture path and key puncture points, combined with advanced labor pain, but there is no significant difference in long-term pain relief.

A Comparison between Accurate Unilateral Puncture Paths Planned by Preoperative and Conventional Unilateral Puncture Techniques in Percutaneous Vertebroplasty.

Objective: Comparison of the clinical and radiological effects of precise unilateral puncture pathway prepared by preoperative CT data and traditional unilateral puncture pathway in PVP administration for the treatment of osteoporotic vertebral compression fractures. Summary of background data. PVP is a commonly used vertebral augmentation operation for the treatment of painful spinal compression fractures. A percutaneous unilateral approach is routinely used to get access to the vertebral body. PVP has had positive clinical results in a number of prior investigations. Numerous difficulties and issues, including puncture difficulty, radiation exposure, cement leakage, spinal cord or nerve damage, and intraspinal hematoma, have been described in contrast. Methods: This prospective study included 300 patients with single-level lumbar osteoporotic vertebral compression fractures, 180 females and 120 males, with an average age of 71.5 years. PVP was performed on randomized subjects using two distinct puncture procedures. The patients were separated into two groups: Preoperative planning, in which a precise unilateral puncture path was established using preoperative CT data, and Conventional planning, in which multiple puncture procedures were used. The participants were followed up on after surgery and mostly assessed on clinical and radiological results. The visual analogue scale for pain and the 36-item Short Form Health Survey (SF-36) questionnaire for health status were used to assess clinical outcomes. Radiation dosage, bone cement distribution, vertebral body height, and kyphotic angle were used to evaluate radiological results. Results: Participants remained monitored for 12 to 28 months on average. 151 individuals were treated with accurate unilateral puncture paths planned by preoperative CT data percutaneous vertebroplasty and 149 patients were treated with conventional unilateral paths percutaneous vertebroplasty. The Preoperative planning group's operation time and radiation dose were significantly lower than the Conventional group's; nevertheless, the volume of injected cement was significantly higher in the Preoperative steering committee than in the Conventional group. All patients in both groups had much less pain after the operations when compared to their preoperative suffering. There were no statistically significant variations between groups when the visual analogue scale and the 36-Item Short Form Health Survey were compared. Neither group showed a substantial decrease in the kyphotic angle during the follow-ups. In the Preoperative planning group, the kyphotic angle improved much more than in the Conventional group. At 1 month postoperatively, 16 patients in the Conventional group experienced apparent discomfort in the puncture sites because to facet joint violation. At the latest follow-up, all of the patients' discomfort had vanished after receiving local block therapy. Conclusion: Both preoperatively designed precise unilateral puncture pathways and traditional unilateral puncture procedures PVP are reasonably safe and effective for individuals with painful osteoporotic spinal compression fractures. Unilateral puncture courses planned via preoperative PVP, on the other hand, absorbed less radiation and operation time, as well as a good level of deformity correction and amount of injected cement, and caused less complications than traditional unilateral PVP.

Three dimensional polyvinyl alcohol scaffolds modified with collagen for HepG2 cell culture.

The creation of in vitro functional hepatic tissue simulating micro environmental niche of the native liver is a keen area of research due to its demand in bioartificial liver. However, it is still unclear how to maintain benign cell function while achieving the sufficient cell quantity. In this work, we aim to prepare a novel scaffold for the culture of HepG2 cells, a liver cell line, by modifying polyvinyl alcohol (PVA) scaffold with collagen (COL). PVA is a kind of synthetic biostable polymer with high hydrophilicity in the human body, has been widely used in the biomedical field. However, the use of PVA is limited in cell cultures due to lack of biologically active functional groups. In this study, amino silane (KH-550), glutaraldehyde and native type I collagen were used to modify three-dimensional PVA scaffold to establish a suitable composite scaffold for hepatocyte culture. Three types of composite scaffolds were prepared for different collagen content, named as PVA/COL (0.2%), PVA/COL (0.5%) and PVA/COL (0.8%), respectively. The composite scaffolds were characterized by SEM, XPS, FTIR, MS, porosity estimation and water contact angle measurement. The PVA/COL (0.8%) scaffolds had the highest collagen content of 12.13%. The composite scaffold showed high porosity with interconnected pores. Furthermore, the biocompatibility between HepG2 cells and scaffolds was evaluated by the ability of cell proliferation, albumin secretion, as well as urea synthesis. The coating of collagen on PVA scaffolds promoted hydrophilicity and HepG2 cell adhesion. Additionally, enhanced cell proliferation, increased albumin secretion and urea synthesis were observed in HepG2 cells growing on collagen-coated three-dimensional PVA scaffolds.