ABSTRACT
[This corrects the article DOI: 10.1016/j.apsb.2021.04.013.].
ABSTRACT
[This corrects the article DOI: 10.1016/j.apsb.2021.04.013.].
ABSTRACT
Dental implant restoration has become the preferred clinical option for the treatment of tooth loss. The basis for the functioning of implant prostheses is good osseointegration of the implant. Osteointegration is a delicate and complex biological process that is not only a simple physical attachment but also initiates and regulates a series of important events such as cell survival, migration, recruitment, and osteogenic differentiation, involving a series of physicochemical changes from the molecular to the cellular level. In-depth studies on osseointegration can facilitate the development of new implants, improve the success rate of implantation in complex clinical conditions, and have important implications for the prevention and treatment of peri-implant diseases. In this review, the research on the regulation of cell signal pathways of implant osseointegration was reviewed, including the biological process of implant osseointegration, integrin-mediated signal pathways, Wnt signal pathways, transforming growth factor-β (TGF-β)/bone morphogenetic protein (BMP) signal pathways, hypoxia-inducible factors (HIFs) signal pathways, Notch signal pathways, Hippo signal pathways, and other signal pathways related to bone integration that are expected to provide some theoretical reference for the optimization of implant performance.
ABSTRACT
Vascular smooth muscle cell (VSMC) migration plays a critical role in the pathogenesis of many cardiovascular diseases. We recently showed that TMEM16A is involved in hypertension-induced cerebrovascular remodeling. However, it is unclear whether this effect is related to the regulation of VSMC migration. Here, we investigated whether and how TMEM16A contributes to migration in basilar artery smooth muscle cells (BASMCs). We observed that AngII increased the migration of cultured BASMCs, which was markedly inhibited by overexpression of TMEM16A. TMEM16A overexpression inhibited AngII-induced RhoA/ROCK2 activation, and myosin light chain phosphatase (MLCP) and myosin light chain (MLC20) phosphorylation. But AngII-induced myosin light chain kinase (MLCK) activation was not affected by TMEM16A. Furthermore, a suppressed activation of integrin
ABSTRACT
Objective:To explore the achievements of clinical teaching and scientific research acquired by visiting scholars funded by medical foundation, which will be benefit for the improvement for cultivation of innovative talents in general hospitals.Methods:Questionnaire data of 132 visiting scholars supported by Beijing Li Huanying Medical Foundation from 2010 to 2016 were analyzed and applied by descriptive statistics.Results:Study abroad has played a positive role in promoting clinical skills, teaching level, and scientific research capacity building. Visitors have significantly improved their teaching titles, mentor positions, paper publishing and approved funding projects, in which there was a year-on-year growth trend high level projects funded.Conclusions:Study abroad is conducive to stimulating the enthusiasm and creativity of medical talents, and also an effective way to enhance the overall strength of the hospital. The foundation exerts the overall planning and leadership role of talent construction, and provides full-chain service and management for overseas study personnel, which is the key to maximize the teaching and research output of medical personnel.
ABSTRACT
BACKGROUND:The biomechanical effect of the implant-bone interface is one of the most important factors for bone resorption. The new structure of the periodontal-ligament-like implants may improve the distribution of the interfacial stress. OBJECTIVE:To discuss the effect of the internal structure changes of traditional implants on the cortical bone stress distribution and peak at the implant-bone interface under different occlusal load conditions, so as to provide a theoretical basis for the optimization design and clinical application of new structure implants. METHODS:Two kinds of digital models, new structure implant (model A) and non-threaded cylindrical implant (model B), were established by Pro/ENGINEER software. Variations of the stress peak and stress distribution of implant-bone interface cortical bone area under the same bone and force environment were analyzed using Ansys software. RESULTS AND CONCLUSION: Under a vertical loading, the stress peak under different forces was reduced by 17.54% in model A compared with model B; under a 45° loading, the stress peak of model A was reduced by 2.59% compared with model B, and it showed an evident tendency of high stress area focusing to the buccal side of model B. Under the chew-simulation loading, the stress peak of model A was lower than that of model B. The biggest difference (0.353 2 MPa) appeared atβ=12°(β is the angle of force direction and the implant axis), and it gradualy reduced atβ > 12°. At the same time, model A had a wider range of application degree compared with model B in two quantitative indicators, including optimal peak stress of promoting bone tissue growth and stress peak of maintaining healthy bone tissue. These results suggest that the optimized structure of implants contributes to improve the cortical bone stress distribution at the implant-bone interface, decrease the peak stress, and reduce the risk of cortical bone absorption in a wider range.
ABSTRACT
Objective To explore the value of diffusion tensor imaging (DTI) and diffusion tensor tracography (DTT) in assessment of Corticospinal tract (CST) and medial lemniscus (ML) in tumors involving brainstem.Methods A total of 35 cases with pathologically confirmed tumors involving brainstem were collected,and 35 volunteers matched with genders and ages were recruited as the normal group.DTI scanning was performed on all the patients and controls.The damage degrees of CST and ML were evaluated and graded by DTT,and the dysfunction degrees were evaluated for the patients.Spearman correlation was used to statistically analyze the relationships of limb movement,sensory dysfunction and CST and ML damage.Results According to the rating results,normal findings,shifting,edema or infiltration and damage of CST was found in 9,9,11,and 6 cases respectively.They were 8,9,15,3 cases for ML.Motor function was normal in 20 cases,slightly defective in 11 cases,and moderate defective in 4 cases.Sensory function was normal in 21 cases,slightly defective in 6 cases,and moderate defective in 8 cases.The patients' dyskinesia and CST damage degree,sensory dysfunction and ML damage degree were positively correlated (r was 0.786 and 0.686 respectively,P < 0.01).The position relationship among tumor and CST and ML could be well displayed on images.None of the patients showed new symptoms of dysneuria after surgery.Conclusions DTI and DTT technology can be used to evaluate CST and ML damage degree in tumors involving brainstem.They can display the position relationship between tumor and the brainstem CST and ML,which is important in protecting the brainstem fiber tract during operation and evaluating the recovery after the operation.