工程技术最新文献

Objective: To explore the synergistic effect of nano-pearl powder (NPP) and adipose-derived stem cell exosomes (ADSC-Exos) on the osteogenic potential of MC3T3-E1 cells.

Methods: The water-soluble matrix of NPP (NPP-WSM) was extracted via freeze-drying, and ADSC-Exos were isolated by ultracentrifugation. NPP-WSM was incorporated into ADSC-Exos through co-incubation to generate NPP-WSM-Exos. MC3T3-E1 cells were treated with NPP-WSM or NPP-WSM-Exos. Cell proliferation and migration were evaluated using CCK-8 and wound-healing assays, respectively. Osteogenic differentiation was assessed by Alizarin Red S staining and alkaline phosphatase (ALP) activity. The expression of osteogenesis-related genes (COL1A1, RUNX2, OCN, and OPN) was measured by qPCR and Western blotting. Transcriptome sequencing (RNA-seq) was conducted to identify signaling pathways activated by NPP-WSM-Exos.

Results: NPP-WSM-Exos displayed distinct exosome morphology and biomarkers, confirming their successful preparation. Significantly, NPP-WSM-Exos enhanced the viability of MC3T3-E1 cells compared to NPP-WSM alone and upregulated the expression of osteogenic genes, including COL1A1, RUNX2, OCN, and OPN, at both the transcriptional and translational levels. Additionally, NPP-WSM-Exos strongly promoted mineralization, as evidenced by the increased calcification observed through Alizarin Red S staining, and elevated alkaline phosphatase (ALP) activity, indicating excellent potential for osteogenic differentiation. Transcriptome sequencing showed that NPP-WSM-Exos significantly enhanced the PI3K/AKT pathway in MC3T3-E1 cells, while protein level detection indicated that NPP-WSM-Exos could increase AKT phosphorylation levels and inhibit GSK3β activity to improve osteogenic efficiency.

Conclusion: The use of adipose-derived stem cell exosomes to encapsulate NPP-WSM can increase the utilization of WSM, promote the proliferation of MC3T3-E1, and enhance the osteogenic differentiation ability.

Decellularized blood vessels with low immunogenicity and excellent biocompatibility are promising for tissue engineering and clinical applications. However, current decellularization methods face limitations in cell removal efficiency, matrix preservation, and biosafety. This study optimized the Triton X-100/SDS (TX-100/SDS) decellularization method using ultrasound technology by systematically evaluating the effects of ultrasound power, temperature, and processing time on decellularization efficiency. The optimized method achieved a 72% reduction in nucleic acid residues at 100 W power while preserving matrix integrity and significantly reducing chemical reagent residues. Structural and biosafety evaluations confirmed that the optimized scaffolds met biological safety standards and demonstrated excellent stability, providing a strong foundation for developing high-performance decellularized vascular materials for clinical applications.

Animal experimental studies involving the Igaki-Tamai stent (ITS), a bioresorbable poly-l-lactic acid scaffold, in peripheral arteries are limited, and existing studies evaluated only short-term (3-month) outcomes. This study compared arterial responses associated with the ITS and bare metal stent (BMS) over 6 months using intravascular ultrasound (IVUS) analysis and evaluated feasibility in porcine iliac arteries. Four miniature pigs underwent stent implantation with the ITS in the right iliac artery and the BMS in the left iliac artery. Follow-up evaluations at 6, 12, and 24 weeks included angiographic and IVUS analyses to assess neointimal hyperplasia, percent area stenosis (%AS), and percent in-stent volume obstruction (%VO). Histological analysis was performed to evaluate tissue injury and inflammation scores. At 6 weeks, the neointimal area did not differ significantly between the ITS and BMS groups (8.49 ± 2.10 mm² vs 13.47 ± 6.67 mm², P = .205). However, the ITS group exhibited a significantly smaller neointimal area at 12 weeks (6.87 ± 1.15 mm² vs 20.65 ± 10.99 mm², P = .050) and 24 weeks (5.20 ± 0.85 mm² vs 22.32 ± 12.03 mm², P = .042). %AS and %VO were significantly lower in the ITS group at all follow-ups. The ITS group showed reduced tissue damage (injury score: 0.80 ± 0.430 vs 1.74 ± 0.908, P < .001) and inflammation (inflammation score: 1.25 ± 0.516 vs 1.67 ± 0.832, P < .001) compared with the BMS group. The ITS was associated with reduced vessel injury, lower inflammatory response, and favorable luminal remodeling over 6 months in healthy porcine iliac arteries.

Background: This study aimed to determine the potential mechanism by which pancreatic stem cell-derived beta cells (PSCs-β) assist in the body's glucose-lowering capacity in type 1 diabetes (T1D) rats.

Methods: We screened the transcriptomic changes in the pancreatic islets of T1D mice to extract key genes from the GSE169275 dataset. Cell proliferation, cell cycle distribution, apoptosis, PSC-β differentiation ability, and insulin production levels were analyzed after MLPH overexpression/knockdown in PSCs. PSC-β-overexpressing MLPH were transplanted into T1D rats, and the changes in fasting blood glucose level, glucose tolerance and insulin, glucagon and C-peptide contents were examined. After the target genes of MLPH were analysed using the database, immunoprecipitation was introduced for validation. Whether RAB3A is involved in the regulatory effects of MLPH on the proliferation and differentiation of PSCs was further verified.

Results: MLPH overexpression further enhanced the proliferation of PSCs, inhibited apoptosis and accelerated the differentiation of PSCs to PSC-β cells and insulin secretion. After the transplantation of MLPH-overexpressing PSC-β cells, the pancreatic islet tissue damage was restored, the insulin expression was substantially elevated and the glucagon content decreased. RAB3A knockdown counteracted the effects of MLPH on the proliferation, differentiation and insulin secretion of PSCs.

Conclusion: MLPH overexpression is favourable for the differentiation of PSCs to insulin β-cells. Transplantation of MLPH-overexpressing PSC-β cells restored the ability of T1D rats to manage a glycemic load by promoting RAB3A expression.

Endovascular aneurysm repair (EVAR) is a widely accepted treatment for aortic pathologies owing to its minimally invasive nature. However, long-term complications, such as stent graft migration and infection, remain unresolved, primarily due to the persistent presence of synthetic materials and limited tissue integration. This pilot study evaluated the feasibility of a novel tissue-engineered stent graft (TESG) combining a bioresorbable poly-L-lactic acid (PLLA) stent with decellularized porcine veins. The veins were processed using a sodium dodecyl sulfate and the Triton X-100 decellularization protocol. Histological and ultrastructural analyses confirmed effective cell removal while preserving extracellular matrix components. Quantitative deoxyribonucleic acid (DNA) analysis showed a > 97% reduction in DNA content. The TESGs were assembled by suturing the decellularized veins into bioresorbable PLLA stents and implanted into porcine iliac arteries (n = 3). Commercially available prosthetic grafts were used as control implants to evaluate differences in tissue responses. Graft patency and morphology were assessed at implantation and on postoperative day 14 using angiography and intravascular ultrasonography. All TESGs remained patent, with no evidence of thrombosis or aneurysmal changes. Histological analysis revealed early endothelialization and smooth muscle cell infiltration within the TESG wall, in contrast to the prosthetic graft controls, which lacked comparable cellular integration. This study demonstrated the short-term feasibility and biological compatibility of a fully bioresorbable TESG. Although long-term outcomes remain to be established, these results support further development of TESG to reduce late complications through improved tissue integration and avoidance of permanent synthetic materials.

Traffic accidents usually result from driver's inattention, sleepiness, and distraction, posing a substantial danger to worldwide road safety. Advances in computer vision and artificial intelligence (AI) have provided new prospects for designing real-time driver monitoring systems to reduce these dangers. In this paper, we assessed four known deep learning models, MobileNetV2, DenseNet201, NASNetMobile, and VGG19, and offer a unique Hybrid CNN-Transformer architecture reinforced with Efficient Channel Attention (ECA) for multi-class driver activity categorization. The framework defines seven important driving behaviors: Closed Eye, Open Eye, Dangerous Driving, Distracted Driving, Drinking, Yawning, and Safe Driving. Among the baseline models, DenseNet201 (99.40%) and MobileNetV2 (99.31%) achieved the highest validation accuracies. In contrast, the proposed Hybrid CNN-Transformer with ECA attained a near-perfect validation accuracy of 99.72% and further demonstrated flawless generalization with 100% accuracy on the independent test set. Confusion matrix studies further indicate a few misclassifications, verifying the model's high generalization capacity. By merging CNN-based local feature extraction, attention-driven feature refinement, and Transformer-based global context modeling, the system provides both robustness and efficiency. These findings show the practicality of using the suggested technology in real-time intelligent transportation applications, presenting a viable avenue toward reducing traffic accidents and boosting overall road safety.

Little is known about whether direct and vicarious rewards affect bilingual language control in social learning. We used a dual-electroencephalogram (EEG) to simultaneously record the effects of direct and vicarious rewards on language control when bilinguals switched between their two languages. We found that both direct and vicarious rewards elicited more switch behavior. On an electrophysiological level, although both direct and vicarious rewards elicited Reward-positivity and Feedback-P3 when receiving reward outcomes, direct rewards induced greater reward effects than vicarious rewards. In addition to an N2 effect in language switching, vicarious rewards elicited more pronounced LPCs relative to direct rewards. More important, in the alpha band, there was a predictive effect of behaviors on rewards in binding vicarious rewards and language switching activities. These findings demonstrate that both direct and vicarious rewards influence language control during language selection.

Ruminative brooding is marked by its perseverative nature. Existing mechanistic theories attribute this to cognitive control deficits linked to elevated functional connectivity within the default mode network and abnormal prefrontal activity. Here, we conceptualize ruminative brooding as an emergent property of a neural attractor state within the default mode network. Stable attractors are mathematically defined by two key properties: (1) convergence over time (assessing attractivity), and (2) resistance to perturbation (assessing stability). We tested whether brain states associated with brooding exhibited these properties in healthy volunteers using EEG during a task-switching protocol that interleaved cued rumination, working memory, and autobiographical memory tasks. Since cued rumination and working memory are thought to engage anticorrelated networks (default mode vs. central executive), switching from cued rumination to working memory effectively "perturbs" this system. Cued rumination was associated with beta power in the posterior cingulate cortex, with rumination disengagement marked by a reduction in beta power in posterior parietal and cingulate cortices. Moreover, high trait rumination was associated with impaired disengagement of these rumination-related dynamics and reduced recruitment of the dlPFC when transitioning from cued rumination to the working memory task, consistent with the "resistance to perturbation" criterion of a stable attractor. Furthermore, trait brooding was positively associated with a reduction in variance in posterior parietal and cingulate cortices time series over the course of cued rumination trials, consistent with the "convergence" criterion. These results provide support for framing brooding-related neural dynamics as pathological attractor states, providing a mechanistic account of rumination's perseverative quality.

Supplementary information: The online version contains supplementary material available at 10.1007/s11571-026-10425-3.

Spiking neural networks (SNNs) have gained significant attention for their biological plausibility, event-driven operation, and low power consumption, establishing them as a leading model for processing event stream data. However, current models often oversimplify neuronal dynamics to balance computational cost and performance. To address this limitation and enhance the dynamical behavior of spiking neurons, this paper introduces two key innovations. First, inspired by biological autaptic connections and memristive devices, we propose the memristive autapse (M-Autapse), a self-connection mechanism that enables adaptive modulation of a neuron's membrane potential. Second, recognizing the need for attention mechanisms that match SNNs' spatio-temporal nature, we design a spatio-temporal synergistic attention (STSA) mechanism to bolster simultaneous focus on both temporal and spatial dimensions of input data. Extensive experiments on the neuromorphic speech benchmarks SHD and SSC validate our methods. On SHD, our model demonstrates performance competitive with the state-of-the-art, while also achieving strong results on the SSC dataset.