BACKGROUND: The osteoinduction by biomaterials has been proven in various animal experiments. OBJECTIVE: To investigate the osteoinduction of porous calcium phosphate cement on bone marrow mesenchymal stem cel s. METHODS: Bone marrow mesenchymal stem cel s were isolated from rabbits aged 1 week in vitro and labeled by PKH-67 or PKH-26, respectively. Forty-eight adult New Zealand white rabbits were randomized into four groups and porous calcium phosphate cement was implanted into both sides of gluteus maximus in each rabbit. Then, 1 mL PKH-26-labeled bone barrow mesenchymal stem cel s (1×1010/L) were injected into the superior gluteal artery branch at each side of gluteus maximus near the femur, and 1 mL PKH-67-labeled bone barrow mesenchymal stem cel s (1×1010/L) injected into tissues around the cement (group A); 1 mL PKH-26-labeled bone barrow mesenchymal stem cel s (1×1010/L) were injected into the each side of superior gluteal artery branch (group B); 1 mL PKH-67-labeled bone barrow mesenchymal stem cel s (1×1010/L) were injected into tissues around the cement (group C); the same amount of normal saline was injected into tissues around the cement (group D). At 3, 7 and 12 weeks after implantation, the cement and its surrounding tissues were extracted and detected by fluorescence microscope and Massion staining. Expression of bone morphogenetic protein 2 was analyzed by RT-PCR. RESULTS AND CONCLUSION: Under fluorescence microscope, PKH-26-labeled bone barrow mesenchymal stem cel s attached fast and distributed homogeneously; however, PKH-67-labeled bone barrow mesenchymal stem cel s attached slowly and exhibited a gradual y homogeneous distribution. Massion staining showed that ectopic new bone formation appeared to have an upward trend in al groups, and the area of new bones in groups A, B and C were larger than that of group D at different time points after implantation. There was a significantly higher expression of bone morphogenetic protein 2 in groups A, B and C compared with the group D at different time points after implantation (P < 0.05), and the expression was the highest in the group A (P < 0.05). In conclusion, the porous calcium phosphate cement can induce bone barrow mesenchymal stem cel s chemotaxis and osteogenetic differentiation. Besides, osteoblasts are differentiated from both the surrounding capil aries and body fluid, and capil ary-derived mesenchymal stem cel s occupy the important position.

Objective To assess the neurophysiological effects of transcranial direct current stimulation (tDCS) of the motor cortex when swallowing.Methods Twenty healthy volunteers had anodal tDCS (a-tDCS), cathodal tDCS (c-tDCS) or sham tDCS applied over the hemisphere with stronger suprahyoid projections, effortful swallowing was performed simultaneously.Suprahyoid motor-evoked potentials (MEPs) on both the stimulated and non-stimulated contra-lateral hemisphere were examined immediately before stimulation and 5,30, 60 and 90 minutes later.The MEPs were normalized and analyzed using two-way repeated measures analysis of variance.Results The tDCS had long-lasting effects on the suprahyoid MEPs bilaterally.There were significant changes in the effect over time.Sham tDCS showed no significant effect.Compared with sham tDCS, a-tDCS significantly increased the excitability of the stimulated hemisphere, but not the non-stimulated projection.Compared with sham tDCS, c-tDCS induced decreased cortical excitability in the stimulated hemisphere but an increase in the non-stimulated projection.Conclusions tDCS during swallowing can alter bilateral swallowing activity in the motor cortex in a polarity-dependent and site-dependent way.A-tDCS enhances the excitability of the stimulated hemisphere while c-tDCS inhibits it ipsilaterally but increases it contralaterally.

Objective To explore the effect of applying surface neuromuscular electrical stimulation (NMES) on the functioning of the upper esophageal sphincter (UES) using the high-resolution solid-state manometry.Methods Seventeen healthy volunteers were selected and given sham stimulation (SS),superior and inferior hyoid stimulation (SIHS),superior hyoid stimulation (SHS) or inferior hyoid stimulation (IHS) at a frequency of 80 Hz and the maximum tolerated level before swallowing.Any changes in the kinematics or biomechanics during swallowing and at rest were recorded using high-resolution solid-state manometry.One-factor repeated analysis of the measurement variance was used.Results A significant decrease in the duration of UES relaxation was observed in response to the electrical stimulation (compared with the sham stimulation).The UES's residual pressure showed a rising trend during electrical stimulation,especially in response to IHS,but the difference compared with SS was not significant.The UES's resting pressure during SIHS increased significantly compared with SS,but there was no significant difference between SHS and IHS in this respect.Conclusions Surface neuromuscular electrical stimulation applied to the neck can immediately change the functioning of the UES.NMES at the maximum tolerated intensity can reduce the duration of UES relaxation,which is important for dysphagia therapy and research.

Purpose To explore the value of texture analysis in the diagnosis and course evaluation of Parkinson's disease(PD)by analyzing the texture features of gray matter nuclei and white matter on quantitative susceptibility mapping(QSM)sequences.Materials and Methods A total of 30 PD patients and 22 normal controls from July 2019 to November 2020 in Jiangyin People's Hospital were prospectively enrolled to perform enhanced gradient echo T2* weighted angiography(ESWAN)sequence scanning.All QSM images were obtained through post-processing.Region of interest was manually obtained,including bilateral caudate heads,globus pallidus,putamen,substantia nigra,red nucleus,cerebellar dentate nucleus and white matter at the center of the semicircle.The texture features of the region of interest were extracted.After dimension reduction and screening,a set of optimal texture parameters were obtained,and a random forest prediction model was constructed.The diagnostic efficiency of the model was analyzed and evaluated and the reliability of the model was evaluated.The correlation between the selected texture features and the clinical scale of PD patients was analyzed.Results A group(n=5)of the best texture feature parameters were obtained from QSM map.The area under curve range of independent prediction PD was 0.697-0.823,the area under curve of random forest model was 0.910,and the accuracy of cross validation was 0.888.Texture feature(r4_wavelet_LLL_firstorder_Energy)of PD group was negatively correlated with the scores of the mini mental state examination(r=-0.470,P=0.011).Conclusion The texture analysis based on QSM has a high diagnostic value for PD,and the texture features of the left putamen have a certain correlation with the cognitive function of PD patients.

Objective:To explore the application of pyrophosphorolysis-activated polymerization(PAP)to monitor plasma cfDNA in ad-vanced non-small cell lung cancer(NSCLC).Methods:A total of 85 patients diagnosed with advanced NSCLC between March 2016 and June 2017 were enrolled in the present study. EGFR mutations in cfDNA extracted from the plasma were detected using PAP and ARMS-PCR technology.The concordance analysis of EGFR mutations involved plasma vs.tumor tissue and PAP vs.ARMS-PCR.Further-more,38 EGFR-positive patients were selected to monitor EGFR mutations with PAP.Results:No statistical differences in EGFR muta-tions were observed between plasma and tumor tissue(P=0.092),as well as PAP and ARMS-PCR(P=0.210).The detection rate of EGFR mutations in cfDNA was higher in the progressor than in the non-progressor(62.5% vs.21.3%,P<0.001).Conclusions:PAP can be used for detecting and monitoring EGFR mutations in cfDNA to predict disease progression.

Objective The aim of this study is to evaluate the effect of repeated sintering and variation in thickness on the color and microstructure of dental lithium disilicate-based glass ceramic veneers. Methods A total of 24 computer aided design and computer aided manufacturing (CAD/CAM) veneers was fabricated using the IPS e.max-CAD LS2 and then randomly divided into four groups (S0, S1, S2, S3; n=6). Each group was sintered 0, 1, 2, 3 times individually according to the manufacturer's recommendation. The color parameters (L, C, H, a, b values) of all the specimens were measured by a Vita easyshade dental colorimeter. The results were statistically analyzed using the SAS 9.1.3 software for MANOVA and LSD. Subsequently, the microstructures of the intersecting surfaces of the specimens were observed by scanning electron microscopy (SEM). Results After repeated sintering, the L value significantly decreased (P<0.05). For the C and b values, statistical differences were observed among the groups except between S2 and S3. SEM results showed that the interlocking microstructures of rod-shaped Li₂Si₂O₅ crystals became more compact when the number of sintering times was increased. Conclusion Repeated sintering exhibited significant influence on the color of the IPS e.max-CAD LS2 veneers.

This review summarizes the applications and advancements of artificial intelligence(AI)in the analysis of retinal vascular parameters. Retinal vascular parameters, including vessel diameter, fractal dimension, vascular tortuosity, branching angles, and vessel density, are important indicators for assessing changes in the retinal vascular network structure. These parameters are not only related to various ophthalmic diseases but also reflect the conditions of systemic diseases such as diabetes and Alzheimer's disease. This article provides a detailed discussion on the advantages of AI technology in the automated identification and quantification of retinal vascular parameters, particularly in improving measurement efficiency and accuracy, and enabling the early detection and monitoring of various diseases. Additionally, the challenges faced by AI in the analysis of retinal vascular parameters were discussed, such as data standardization and insufficient sample diversity, and proposes directions for future research. By thoroughly analyzing the application of AI in retinal vascular parameter analysis, this article aims to offer new perspectives and methods for clinical diagnosis and early intervention of diseases, holding significant clinical significance and application prospects.