Brain-computer interface (BCI) based on functional near-infrared spectroscopy (fNIRS) is a new-type human-computer interaction technique. To explore the separability of fNIRS signals in different motor imageries on the single limb, the study measured the fNIRS signals of 15 subjects (amateur football fans) during three different motor imageries of the right foot (passing, stopping and shooting). And the correlation coefficient of the HbO signal during different motor imageries was extracted as features for the input of a three-classification model based on support vector machines. The results found that the classification accuracy of the three motor imageries of the right foot was 78.89%±6.161%. The classification accuracy of the two-classification of motor imageries of the right foot, that is, passing and stopping, passing and shooting, and stopping and shooting was 85.17%±4.768%, 82.33%±6.011%, and 89.33%±6.713%, respectively. The results demonstrate that the fNIRS of different motor imageries of the single limb is separable, which is expected to add new control commands to fNIRS-BCI and also provide a new option for rehabilitation training and control peripherals for unilateral stroke patients. Besides, the study also confirms that the correlation coefficient can be used as an effective feature to classify different motor imageries.
Objective To investigate the causal relationship between 91 circulating inflammatory proteins and respiratory tract infection by bidirectional Mendelian randomization. Methods single nucleotide polymorphisms (SNPs) for 91 inflammatory circulating proteins were derived from GWAS data from a genome-wide association study of 14 824 subjects of European ancestry on the Olink Target platform, and SNPs for acute bronchitis, acute bronchiolitis, and acute laryngitis and tracheitis were derived from GWAS pooled data in the FinnGen database. Inverse variance weighting method was used as the main research method to conduct bidirectional Mendelian randomization analysis, and Cochran’ IVW Q test, MR-Egger regression method and one by one elimination method were used to conduct sensitivity tests to evaluate heterogeneity and horizontal pleiotropy. In order to reduce the incidence of Class I errors and improve the feasibility of the study, Bonferroni correction was performed.ResultsLevels of C hemokine C-X-C motif ligand 6 (CXCL6), matrix metalloproteinase-1 (MMP-1), hepatocyte growth factor (HGF), interleukin-10 (IL-10), chemokine C-X3-C motif ligand 1 (CX3CL1), and TNF-related activation-induced cytokine (TRANCE) were causally associated with acute bronchitis. MMP-1 level [OR: 1.239 0, 95%CI: 1.111 6-1.382 2, P<0.000 5] had a significant causal relationship with acute bronchitiss and played a promoting role. Levels of macrophage inflammatory protein-1α (MIP-1α), signaling lymphocyte activating molecules, and FMS-associated tyrosine kinase 3 ligand (FIt3L) were potentially causally associated with acute bronchiolitis. There was a potential causal relationship between C-X-C motif chemokine 5 (CXCL5), T cell surface glycoprotein CD6 subtype (CD6), fibroblast growth factor 19 (FGF-19), C-C motif chemokine 23 (CCL23), monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor ligand superfamily member 12 (TNFSF12) levels and acute laryngitis and tracheitis. In reverse Mendelian randomization analysis, there were no positive results between acute bronchitis, acute bronchiolitis and 91 inflammatory factors. Acute laryngitis and tracheitis [OR: 1.076 3,95%CI: 1.012 9-1.143 7, P=0.017 6] were potentially causally associated with FGF-19 levels. Conclusions MMP-1 level have a significant causal relationship with acute bronchitis. The levels of other inflammatory factors such as CXCL6, HGF, MIP-1 alpha, FIt3L, CXCL5, FGF-19 are potentially causally associated with respiratory tract infections. MMP-1 may be an important target for the prediction or treatment of acute bronchitis.
Objective To extend its application in the field of bone repair by adding oxygen-carboxymethylated chitosan (O-CMC) and gentamicin for modification of the calcium sulfate cement (CSC). Methods The O-CMC/CSC was prepared by adding O-CMC with different concentrations (0.1wt%, 0.3wt%, 0.5wt%, 0.7wt%, and 1.0wt%) in the CSC liquid phase. The effect of O-CMC on the CSC was evaluated by testing the injectability, compressive strength, degradation rate, pH value, cytotoxicity and osteogenesis. After the optimal concentration of O-CMC was determined, gentamicin with different concentrations (0.5wt%, 1.5wt%, and 2.5wt%) was added in the O-CMC/CSC, and then the compressive strength and antibacterial properties were investigated. Results After adding O-CMC in the CSC liquid phase, the injection time of O-CMC/CSC was increased to more than 5 minutes; it significantly prolonged with increased concentration of O-CMC (P<0.05). The compressive strength of the modified bone cement was in the range of 11-18 MPa and it was the highest when the concentration of O-CMC was 0.5wt% (P<0.05). The degradation rate of O-CMC/CSC was not influenced obviously by O-CMC (P>0.05). The pH value was in the range of 7.2-7.4 and Ca2+ concentration was in the range of 6-8 mmol/L.In vitro mineralization experiment indicated that the induced mineralization ability of O-CMC/CSC was much higher than that of pure CSC. The 0.5wt% O-CMC/CSC had the best performance; the compressive strength of the composite bone cement was above 5 MPa after gentamicin was added, which had antibacterial effect. Conclusion O-CMC is able to effectively improve the injection, compressive strength, and osteogenic activity of CSC; in addition, antibacterial properties is obtained in the CSC after adding gentamicin.
Objective To design and construct a graphene oxide (GO)/silver nitrate (Ag3PO4)/chitosan (CS) composite coating for rapidly killing bacteria and preventing postoperative infection in implant surgery. Methods GO/Ag3PO4 composites were prepared by ion exchange method, and CS and GO/Ag3PO4 composites were deposited on medical titanium (Ti) sheets successively. The morphology, physical image, photothermal and photocatalytic ability, antibacterial ability, and adhesion to the matrix of the materials were characterized. Results The GO/Ag3PO4 composites were successfully prepared by ion exchange method and the heterogeneous structure of GO/Ag3PO4 was proved by morphology phase test. The heterogeneous structure formed by Ag3PO4 and GO reduced the band gap from 1.79 eV to 1.39 eV which could be excited by 808 nm near-infrared light. The photothermal and photocatalytic experiments proved that the GO/Ag3PO4/CS coating had excellent photothermal and photodynamic properties. In vitro antibacterial experiments showed that the antibacterial rate of the GO/Ag3PO4/CS composite coating against Staphylococcus aureus reached 99.81% after 20 minutes irradiation with 808 nm near-infrared light. At the same time, the composite coating had excellent light stability, which could provide stable and sustained antibacterial effect. ConclusionGO/Ag3PO4/CS coating can be excited by 808 nm near infrared light to produce reactive oxygen species, which has excellent antibacterial activity under light.