Objective To explore the effects of narrative intervention and different intervention models on children at risk for developmental language disorders (DLD). Methods Using a random number table method, thirty children at risk for DLD in Yuhua District, Changsha City, were selected from September to December 2024 and randomly assigned to three groups: individual group (n=10), peer group (n=10), and control group (n=10). The individual and peer groups (2-3 children per peer group) received a 20-hour narrative intervention, while the control group did not receive any intervention. The Little Frog, Where Are You? test was used to assess the children’s narrative abilities, and both global and local coherence error rates were analyzed. Results A total of 24 children were enrolled in the final analysis, including 7 in the individual group, 9 in the peer group, and 8 in the control group. Compared with pre-intervention levels, in the individual group, within-group differences in global and local coherence error rates at 1 week and 3 months post-intervention were statistically significant (all P<0.05) with large effect sizes (Cohen’s |d|>1); in the peer group, only the within-group difference in local coherence error rate at 1 week post-intervention reached statistical significance (P<0.05), with a large effect size (Cohen’s |d|>1); in the control group, within-group differences in global coherence error rate were statistically significant at both 1 week and 3 months post-intervention (both P<0.05), with large effect sizes (Cohen’s |d|>1). Between-group comparisons revealed that at 1 week post-intervention, statistically significant differences in local coherence error rates were observed between both intervention groups and the control group (both P<0.05), with large effect sizes (Cohen’s |d|>1); 3 months post-intervention, the difference in global coherence error rate between the individual group and the control group was statistically significant (P<0.05) and exhibited a large effect size (Cohen’s |d|>1); no statistically significant intergroup differences were identified in any other pairwise comparisons (all P>0.05). Conclusions Early narrative intervention has a preliminary positive effect on enhancing the narrative coherence in children at risk for DLD. In clinical practice, either individualized intervention or peer participatory intervention can be used independently, or the advantages of both approaches can be integrated by alternating individual and peer collaborative interventions.
Objective To analyze the distribution of stress in the upper and lower plates of the prosthesis-bone interface, and the effect of interface pressure on osseointegration. Methods CT scanning was performed on goats at 1 week after artificial cervical disc replacement to establish the finite element model of C3, 4. The stress distribution of the upper and lower plates of the interface was observed. At 6 and 12 months after replacement, Micro-CT scan and three dimensional reconstruction were performed to measure the bone volume fraction (BVF), trabecular number (Tb. N), trabecular thickness (Tb. Th), trabecular separation (Tb. Sp), bone mineral density (BMD), bone surface/bone volume (BS/BV), and trabecular pattern factor (Tb. Pf). The C3 lower plate and C4 upper plate of 4 normal goat were chosen to made the cylinder of the diameter of 2 mm. The gene expressions of receptor activator for nuclear factor κB ligand (RANKL), osteoprotegerin (OPG), transforming growth factor β (TGF-β), and macrophage colony-stimulating factor (M-CSF) were detected by real time fluorescent quantitative PCR at immediate after cutting and at 24 and 48 hours after culture. The samples of appropriate culture time were selected to made mechanical loading, and the gene expressions of RANKL, OPG, M-CSF, and TGF-β were detected by real time fluorescent quantitative PCR; no mechanical loading samples were used as normal controls. Results Under 25 N axial loading, the stress of the upper plate of C3, 4 was concentrated to post median region, and the stress of the lower plate to middle-front region and two orbits. According to stress, the plate was divided into 5 regions. The Micro-CT scan showed that BMD, Tb.Th, BVF, and Tb.N significantly increased, and BS/BV, Tb.Sp, and Tb.Pf significantly decreased at 12 months after replacement when compared with ones at 6 months (P<0.05). At 24 and 48 hours after culture, the gene expressions of RANKL, OPG, and TGF-β were signifi-cantly higher than those at immediate (P<0.05), but no significant difference was found between at 24 and 48 hours after culture (P>0.05). The mechanical loading test results at 24 hours after culture showed that the RANKL and OPG gene expressions and OPG/RANKL ratio in C3 lower plate and C4 upper plate were significantly up-regulated when compared with controls (P<0.05), but no significant difference was shown in TGF-β and M-CSF gene expressions (P>0.05). Conclusion Domestic artificial cervical disc endplate has different pressure distribution, the stress of lower plate is higher than that of upper plate. Pressure has important effect on local osseointegration; the higher pressure area is, the osseointegration is better. Under the maximum pressure in interface, the osteoblast proliferation will increase, which is advantageous to the local osseointegration.