Bone Marrow Mesenchymal Stem Cell-Derived Exosomes Alleviate Nuclear Pulposus Cells Degeneration Through the miR-145a-5p/USP31/HIF-1α Signaling Pathway.

Bone marrow mesenchymal stem cell (BMSC)-derived exosomes possess therapeutic potential against degenerative diseases. This study aimed to investigate the effects of BMSC-derived exosomes on intervertebral disc degeneration (IVDD) and explore the underlying molecular mechanisms. Through transcriptome sequencing and histological analysis, we observed a significant increase in HIF-1α expression in degenerative nucleus pulposus (NP) tissues. The addition of HIF-1α resulted in elevated expression of inflammatory factors IL-1ß and IL-6, higher levels of matrix-degrading enzyme MMP13, and lower expression of aggrecan in NP cells. Co-culturing with BMSCs diminished the expression of HIF-1α, MMP13, IL-1ß, and IL-6 in degenerative NP cells induced by overload pressure. miRNA chip analysis and PCR validation revealed that miR-145a-5p was the primary miRNA carried by BMSC-derived exosomes. Overexpression of miR-145a-5p was effective in minimizing the expression of HIF-1α, MMP13, IL-1ß, and IL-6 in degenerative NP cells. Luciferase reporter assays confirmed USP31 as the target gene of miR-145a-5p, and the regulation of NP cells by BMSC-derived exosomes via miR-145a-5p was dependent on USP31. In conclusion, BMSC-derived exosomes alleviated IVDD through the miR-145a-5p/USP31/HIF-1α signaling pathway, providing valuable insights into the treatment of IVDD.

Comparing Clinical and Radiographic Outcomes Between the Self-locking Stand-alone Cage and Conventional Cage-plate Construct: A Five-year Retrospective Cohort Study.

STUDY DESIGN/SETTING: A retrospective cohort study. OBJECTIVE: To evaluate the clinical efficacy of the self-locking stand-alone (SA) cage and conventional cage-plate construct (CPC) in treating degenerative cervical spondylosis with a five-year follow-up. SUMMARY OF BACKGROUND DATA: The SA approach was designed to reduce complications associated with traditional anterior cervical discectomy and fusion. These techniques have been shown to have satisfactory short-term clinical outcomes. Literature describing the mid-term clinical outcomes of SA cage is limited. MATERIALS AND METHODS: We retrospectively analyzed patients with cervical spondylosis who had received an SA device or CPC between 2014 and 2016 at the Xijing Hospital. Participants were matched for sex, age, and operative level. Differences in clinical and radiographic outcomes and the occurrence of postoperative complications between the two groups were analyzed. RESULTS: In total, 207 patients were included (101 with SA and 106 with CPC), the median follow-up for both groups were 60.2 and 60.9 months. Both groups exhibited significant improvements in all measured values compared with the preoperative values. The SA group had a shorter operation time, less intraoperative blood loss, and a significantly lower incidence of dysphagia after surgery than the CPC group ( P <0.05). At the last visit, cage subsidence was 6.9% and 3.8% in the SA and CPC groups, respectively ( P =0.365). The radiographic adjacent segment degeneration (ASD) was significantly lower in the SA group than in the CPC group (6.9% vs. 27.4%, P <0.01). No symptomatic ASD was observed in the SA group, and six (5.7%) cases occurred in the CPC group ( P =0.029). CONCLUSIONS: In this study, the SA cage showed similar efficacy to that of the conventional CPC in treating cervical spondylosis using anterior cervical discectomy and fusion, with a significant reduction in the incidence of immediate postoperative dysphagia and mid-term ASD.

Toward Risk Reduction for Mobile Service Composition.

The advances in mobile technologies enable us to consume or even provide services through powerful mobile devices anytime and anywhere. Services running on mobile devices within limited range can be composed to coordinate together through wireless communication technologies and perform complex tasks. However, the mobility of users and devices in mobile environment imposes high risk on the execution of the tasks. This paper targets reducing this risk by constructing a dependable service composition after considering the mobility of both service requesters and providers. It first proposes a risk model and clarifies the risk of mobile service composition; and then proposes a service composition approach by modifying the simulated annealing algorithm. Our objective is to form a service composition by selecting mobile services under the mobility model and to ensure the service composition have the best quality of service and the lowest risk. The experimental results demonstrate that our approach can yield near-optimal solutions and has a nearly linear complexity with respect to a problem size.

Optimal Group Size for Software Change Tasks: A Social Information Foraging Perspective.

Group size is a key factor in collaborative software development and many other cybernetic applications where task assignments are important. While methods exist to estimate its value for proprietary projects, little is known about how group size affects distributed and decentralized cybernetic applications and in particular open source software (OSS) development. This paper presents a novel approach in which we frame developers' collective resolution of OSS change tasks as a social information foraging problem. This new perspective enables us to predict the optimal group size and quantify group size's effect on individual performance. We test the theory with data mined from two projects: 1) Firefox and 2) Mylyn. This paper not only uncovers the mismatch of optimal and actual group sizes, but also reveals the association of optimality with improved productivity. In addition, the social-level productivity gain is observed as project evolves. We show this paper's impact by extending the frontiers of knowledge in two areas: 1) social coding and 2) recommendation systems.