Possible causes of atherosclerosis: lncRNA COLCA1 induces oxidative stress in human coronary artery endothelial cells and impairs wound healing.

Background: Atherosclerosis is the most common cause of cardiovascular disease, accompanied by high mortality and poor prognosis. Low-density lipoprotein (LDL) and its oxidized form oxidized low-density lipoprotein (oxLDL) play an important role in atherosclerosis. This article will explore the role of the lncRNA COLCA1 (colorectal cancer associated 1)/hsa-miR-371a-5p/SPP1 (secreted phosphoprotein 1) pathway in oxLDL in causing human coronary artery endothelial cells (HCAECs) inflammation and related biological function changes. Methods: OxLDL was used to stimulate HCAECs. The inflammatory response and biological function changes of HCAECs were analyzed, total RNA-seq was performed on HCAECs before and after stimulation, and RT-Qpcr (real-time quantitative PCR) was used to verify the differential genes. Interference of the expression of COLCA1 in HCAECs was performed by siRNA interference technology to verify the role of COLCA1 in the biological function changes of HCAECs after oxLDL stimulation, and further prove that COLCA1 affects SPP1 through hsa-miR-371a-5p. Results: OxLDL can affect the oxidative stress response of HCAECs, which in turn affects the apoptosis and wound healing ability of HCAECs. COLCA1 and SPP1 were highly expressed after oxLDL stimulation, while hsa-miR-371a-5p was the opposite. After COLCA1 interference, the oxidative stress level of HCAECs stimulated by oxLDL decreased, the apoptosis level also significantly decreased, and the wound healing ability was enhanced. After simultaneous COLCA1 interference and recovery of the expression of hsa-miR-371a-5p, these improved functions disappeared. The dual-luciferase assay confirmed that hsa-miR-371a-5p and COLCA1, hsa-miR-371a-5p and SPP1 has binding targets. Conclusions: OxLDL can up-regulate the expression of COLCA1 in HCAECs, which in turn affects the intracellular COLCA1/hsa-miR-371a-5p/SPP1 pathway to regulate the level of oxidative stress in cells. This in turn affects the level of apoptosis and wound healing ability, which causes cells to produce a continuous inflammatory response.

Treatment of open tibial diaphyseal fractures by external fixation combined with limited internal fixation versus simple external fixation: a retrospective cohort study.

BACKGROUND: The treatment of open tibial shaft fractures is challenging. External fixation (EF) is comparatively safe in treating these open injuries, meanwhile it has the advantages of easy application, minimal additional disruption, and convenient subsequent soft tissue repair. Nevertheless, its application is accompanied by a series of problems in alignment and bone healing. Therefore, limited internal fixation (LIF), such as cortical screws, has been used based on the external fixator for better therapeutic effect. The aim of this study is to compare the outcomes of EF combined with LIF and simple EF in the management of open tibial shaft fractures, evaluating the efficacy and safety of using the combined technique in treating such fractures. METHODS: From January 2012 to December 2016, patients with open tibial shaft fractures treated with EF with or without LIF augmentation were identified. A total of 152 patients were included in the analysis, and there were 85 patients in the simple external fixation group and 67 patients in the EF-LIF group. General assessment indicators included the direct cost of hospitalization and the times of first surgery, full weight bearing, and complete union. Infections and complications in union or limb alignment were compared as primary outcomes. Additionally, the number of patients who changed the fixation system for various reasons were analysed. RESULTS: Effective follow-up of all participants for statistical analysis was obtained. The follow-up time averaged 17.15 months (range: 12.00 to 24.00 months) in the EF group and 16.20 months (range: 12.00 to 19.00 months) in the EF-LIF group. Combined fixation provided shortened time to bear full weight and achieve complete bone union, while requiring additional first surgery time. No significant difference was found in infection rates or direct cost of hospitalization. Delayed union and non-union in the EF-LIF group were significantly decreased (20.9% versus 40.0, 1.5% versus 14.1%, p < 0.05). In limb alignment, patients with combined fixation exhibited reduced malreduction, loss of reduction, and malunion. In terms of secondary fixation, the EF-LIF group showed a markedly lower incidence (5.8% versus 34.1%, p < 0.001). CONCLUSION: Compared with simple EF, combined fixation is an effective and safe alternative for management of open tibial diaphyseal fractures. It provides superior initial reduction, better stability and decreases the risk of inferior alignment and delayed union without increasing the risk of infection.

Application of a Ni-Ti arched shape-memory connector in unstable lateral malleolus fractures: A retrospective study.

PURPOSE: To compare the outcomes of the arched shape-memory connector (ASC) only fixation and the lateral one-third tubular plate fixation in managing unstable Type A or B lateral malleolus fractures according to the Weber (AO) classification, and to evaluate the feasibility and reliability of ASC only fixation in treating these fractures. METHODS: From January 2010 to January 2015, 148 patients with Type A or B (Weber (AO) classification) lateral malleolus fractures treated with the arched shape-memory connector (ASC) only fixation or lateral plate fixation were included. There were 66 patients in the ASC only fixation group and 82 patients in the lateral plate group. Intergroup differences were absent regarding patient and fracture characteristics. The incision length, complete-union time, major complications and complaints, incidence of hardware removal, and final radiographic and functional evaluations were compared. RESULTS: The follow-up time averaged 18.2 months in the ASC fixation group and 17.2 months in the lateral plate group. The ASC only fixation group had significantly decreased wound infection (4.55% versus 14.63%) and skin necrosis (none versus 7.32%). Of patients who underwent ASC only fixation 3.03% reported lateral ankle pain, 7.58% received palpable hardware, and 3.03% reported hardware irritation, while the corresponding observations in the lateral plate group were 19.51%, 54.88%, and 14.63%, respectively, representing a statistical difference. Furthermore, compared with the lateral plate group, the incidence of hardware removal was markedly lower in the ASC fixation group (12.12% versus 30.49%). In terms of reduction accuracy, complete-union time, and AOFAS scores, no appreciable differences were observed. CONCLUSIONS: ASC only fixation is a reliable alternative for managing Type A or B lateral malleolus fractures, leading to fewer soft tissue complications, fewer hardware complaints, and a reduced need for hardware removal, and a reduced need for hardware removal. In addition, ASC can be used for augmented plate fixation in certain comminuted fracture patterns.

Stem cell-derived exosomes: A promising strategy for fracture healing.

OBJECTIVES: To describe the biological characteristics of exosomes and to summarize the current status of stem cell-derived exosomes on fracture healing. Meanwhile, future challenges, limitations and perspectives are also discussed. METHODS: Search and analyze the related articles in pubmed database through the multi-combination of keywords like "stem cells","exosomes","bone regeneration" and "fracture healing". CONCLUSION: Stem cell-derived exosome therapy for fracture healing has been enjoying popularity and is drawing increasing attention. This strategy helps to promote proliferation and migration of cells, as well as osteogenesis and angiogenesis, in the process of bone formation. Although the exact mechanisms remain elusive, exosomal miRNAs seem to play vital roles. Future studies are required to solve multiple problems before clinical application, including comprehensive and thorough understanding of exosomes, the exact roles of exosomes in regulating bone formation, and the optimal source, dose and frequency of treatment, as well as technical and safety issues. Moreover, studies based on fracture models of large animals are could offer guidance and are in demand.

Stem cell therapy: a promising biological strategy for tendon-bone healing after anterior cruciate ligament reconstruction.

Tendon-bone healing after anterior cruciate ligament (ACL) reconstruction is a complex process, impacting significantly on patients' prognosis. Natural tendon-bone healing usually results in fibrous scar tissue, which is of inferior quality compared to native attachment. In addition, the early formed fibrous attachment after surgery is often not reliable to support functional rehabilitation, which may lead to graft failure or unsatisfied function of the knee joint. Thus, strategies to promote tendon-bone healing are crucial for prompt and satisfactory functional recovery. Recently, a variety of biological approaches, including active substances, gene transfer, tissue engineering and stem cells, have been proposed and applied to enhance tendon-bone healing. Among these, stem cell therapy has been shown to have promising prospects and draws increasing attention. From commonly investigated bone marrow-derived mesenchymal stem cells (bMSCs) to emerging ACL-derived CD34+ stem cells, multiple stem cell types have been proven to be effective in accelerating tendon-bone healing. This review describes the current understanding of tendon-bone healing and summarizes the current status of related stem cell therapy. Future limitations and perspectives are also discussed.