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Lithium metal anodes (LMAs) present limitations for practical applications due to dendritic Li growth and infinite volume expansion during cycling. Lithium carbon composites exhibit great potential to address these issues owing to the promotion of Li ion diffusion by offering a stable Li host. Herein, we report the fabrication of a carbon-based lithium metal (GKBLi) anode through a ball milling approach by exploiting a mixture of passivated lithium metal powder and graphitic carbon nanomaterials (GKB). The in situ mechanical chemistry lithiation reaction between GKB and Li forms graphite intercalation compounds that exhibit lithiophilicity and generate Li3N, which effectively promotes the transport of Li ions. The highly uniform distribution of Li and GKB in the anode matrix can enable the deposition and stripping of Li homogeneously. The GKBLi symmetrical cell can stably cycle for more than 1200 h with low voltage hysteresis. Impressively, a full cell assembled with a GKBLi anode and commercial LiFePO4 cathode achieves extraordinary cycling stability with a capacity retention of 90.9% over 1000 cycles at a high current of 2C. This highly uniform distribution of lithium in the electrodes by a simple dry preparation method provides new insight into high-performance LMAs on an industrial scale. [ABSTRACT FROM AUTHOR]

As a common algorithm in mobile robot path planning, grid method has the characteristics of less information and simple structure, but the traditional grid method usually affects the effectiveness of the algorithm because of its excessive grid. In order to solve this problem, this paper proposes an improved grid method for feature points extraction. This method uses the idea of feature extraction to extract the vertices of obstacle grid as feature points, and carries out path planning among these feature points. This method simplifies the planning scope of the algorithm. The new grid method is applied to different kinds of path planning algorithms and compared with the traditional grid method. The results show that this modeling method can solve the local optimization problem of artificial potential field method and make the planned path safer; reduce the number of grid search grid of A* algorithm, make A* algorithm search more purposeful, and improve the efficiency of A* algorithm search; at the same time, the ant colony algorithm does not search path by grid, reducing the calculation times of transition probability and speeding up the algorithm iteration speed. [ABSTRACT FROM AUTHOR]

BACKGROUND: The proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) can delay the procession of steroid-induced femoral head necrosis. Besides, microRNA-141 (miR-141) is one of the important regulatory factors to promote cell proliferation. In addition, velvet antler is a traditional Chinese medicine which has significant roles in repairing bone and tissue and improving health. OBJECTIVE: To investigate whether velvet antler serum can regulate the expression of miR-141 to promote the proliferation of BMSCs, and further delay or reverse the progression of steroid-induced femoral head necrosis. METHODS: BMSCs were isolated and cultured from Sprague-Dawley rats. The passage 3 BMSCs were transfected with miR-141 mimic or miR-141 inhibitors, and then real-time PCR and methyl thiazolyl tetrazolium (MTT) assay were performed for detecting miR-141 expression and cell proliferation, respectively. The passage 3 BMSCs were divided into three groups: control group (α-MEM), dexamethasone group (α-MEM+1 μmol/L dexamethasone), and velvet antler serum group (α-MEM+1 μmol/L dexamethasone+15% velvet antler serum). Expression of miR-141 mRNA was detected by real-time PCR at 24 hours after intervention. The proliferation ability of BMSCs was evaluated by MTT assay at 24, 48, and 72 hours after intervention. RESULTS AND CONCLUSION: After transfection with miR-141 mimic, the expression of miR-141 mRNA was upregulated, while the cell proliferation was reduced. After transfection with miR-141 inhibitor, the expression of miR-141 mRNA was downregulated, while the cell proliferation was increased. The expression of miR-141 mRNA was significantly higher in the dexamethasone group than the control group (P < 0.01), while the treatment with velvet antler serum could significantly downregulate the expression of miR-141 mRNA (P < 0.01). The absorbance of BMSCs in the dexamethasone group was significantly lower than that in the control group (P < 0.01), and the absorbance value in the velvet antler serum group was significantly higher than that in the dexamethasone group (P < 0.01). In conclusion, the serum containing velvet antler can downregulate the expression of miR-141 which is upregulated by dexamethasone and then do help to promote the proliferation of BMSCs. [ABSTRACT FROM AUTHOR]

Objective Methods Results Conclusion Osteoporosis is a severe bone disease with a complex pathogenesis involving various immune processes. With the in‐depth understanding of bone immune mechanisms, discovering new therapeutic targets is crucial for the prevention and treatment of osteoporosis. This study aims to explore novel bone immune markers related to osteoporosis based on single‐cell and transcriptome data, utilizing bioinformatics and machine learning methods, in order to provide novel strategies for the diagnosis and treatment of the disease.Single cell and transcriptome data sets were acquired from Gene Expression Omnibus (GEO). The data was then subjected to cell communication analysis, pseudotime analysis, and high dimensional WGCNA (hdWGCNA) analysis to identify key immune cell subpopulations and module genes. Subsequently, ConsensusClusterPlus analysis was performed on the key module genes to identify different diseased subgroups in the osteoporosis (OP) training set samples. The immune characteristics between subgroups were evaluated using Cibersort, EPIC, and MCP counter algorithms. OP's hub genes were screened using 10 machine learning algorithms and 113 algorithm combinations. The relationship between hub genes and immunity and pathways was established by evaluating the immune and pathway scores of the training set samples through the ESTIMATE, MCP‐counter, and ssGSEA algorithms. Real‐time fluorescence quantitative PCR (RT‐qPCR) testing was conducted on serum samples collected from osteoporosis patients and healthy adults.In OP samples, the proportions of bone marrow‐derived mesenchymal stem cells (BM‐MSCs) and neutrophils increased significantly by 6.73% (from 24.01% to 30.74%) and 6.36% (from 26.82% to 33.18%), respectively. We found 16 intersection genes and four hub genes (DND1, HIRA, SH3GLB2, and F7). RT‐qPCR results showed reduced expression levels of DND1, HIRA, and SH3GLB2 in clinical blood samples of OP patients. Moreover, the four hub genes showed positive correlations with neutrophils (0.65–0.90), immature B cells (0.76–0.92), and endothelial cells (0.79–0.87), while showing negative correlations with myeloid‐derived suppressor cells (negative 0.54–0.73), T follicular helper cells (negative 0.71–0.86), and natural killer T cells (negative 0.75–0.85).Neutrophils play a crucial role in the occurrence and development of osteoporosis. The four hub genes potentially inhibit metabolic activities and trigger inflammation by interacting with other immune cells, thereby significantly contributing to the onset and diagnosis of OP. [ABSTRACT FROM AUTHOR]

Background: The role of gut bacteria in preventing and delaying osteoporosis has been studied. However, the causal relationship between gut bacteria, plasma proteins, circulating metabolites and osteoporosis (OP) risk has not been fully revealed., Materials and Methods: In this study, a two-sample Mendelian randomization study (MR) approach was used to assess the causal associations between gut bacteria, plasma proteins and circulating metabolites, and osteoporosis risk using Genome Wide Association Study (GWAS) data from gut bacteria(n=8208), plasma proteins(n=2263), circulating metabolites (n=123), and osteoporosis (3203 cases and 16380452 controls). Inverse-variance weighted (IVW) was used as the main analytical method to estimate the MR causal effect and to perform directional sensitivity analysis of causality. Finally, the mediating effect values for the influence of gut flora on OP pathogenesis through circulating metabolites were calculated by univariate MR analysis, and multivariate MR analysis. Next, we evaluated the effect of Phosphatidylcholine on the osteogenic function of bone marrow mesenchymal stem cells (BMSCs) through relevant experiments, including Edu detection of cell proliferation, alkaline phosphatase (ALP) staining, Alizarin red staining to evaluate osteogenic function, qPCR and WB detection of osteogenic differentiation related gene expression., Results: A total of 9 gut microbial taxa, 15 plasma proteins and eight circulating metabolites were analysed for significant causal associations with the development of OP. Significant causal effects of 7 on gut bacteria, plasma proteins and circulating metabolites were analysed by univariate MR analysis and these results were used as exposure factors for subsequent multivariate MR. Multivariate MR analyses yielded a significant effect of circulating metabolites Phosphatidylcholine and other cholines on OP (P<0.05). Further mediation effect analysis showed that the mediation effect of Bifidobacteriaceae affecting OP through the circulating metabolite Phosphatidylcholine and other cholines was -0.0224, with a 95 % confidence interval for the mediation effect that did not include 0, and the complete mediation effect was significant. Phosphatidylcholine can promote BMSCs proliferation and osteogenesis., Conclusion: Our study demonstrated significant causal associations of gut bacteria, plasma proteins and circulating metabolites on OP, and that Bifidobacteriaceae affect OP through the circulating metabolites Phosphatidylcholine and other cholines. Phosphatidylcholine affects the osteogenic ability of BMSCs. Further exploration of potential microbiota-associated mechanisms of bone metabolism may offer new avenues for osteoporosis prevention and treatment of osteoporosis., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)