Complement C3 plays a critical role in periodontitis. However, its source, role and underlying mechanisms remain unclear. In our study, by analyzing single-cell sequencing data from mouse model of periodontitis, we identified that C3 is primarily derived from periodontal fibroblasts. Subsequently, we demonstrated that C3a has a detrimental effect in ligature-induced periodontitis. C3ar^-/- mice exhibited significantly less destruction of periodontal support tissues compared to wild-type mice, characterized by mild gingival tissue damage and reduced alveolar bone loss. This reduction was associated with decreased production of pro-inflammatory mediators and reduced osteoclast infiltration in the periodontal tissues. Mechanistic studies suggested that C3a could promote macrophage polarization and osteoclast differentiation. Finally, by analyzing single-cell sequencing data from the periodontal tissues of patients with periodontitis, we found that the results observed in mice were consistent with human data. Therefore, our findings clearly demonstrate the destructive role of fibroblast-derived C3 in ligature-induced periodontitis, driven by macrophage M1 polarization and osteoclast differentiation. These data strongly support the feasibility of C3a-targeted interventions for the treatment of human periodontitis.
Animals ; Osteoclasts/cytology* ; Periodontitis/metabolism* ; Cell Differentiation ; Mice ; Fibroblasts/metabolism* ; Macrophages ; Disease Models, Animal ; Complement C3/metabolism* ; Humans ; Disease Progression ; Mice, Inbred C57BL ; Male ; Mice, Knockout

Objective:To explore the association between the gross motor development of children and Chi-nese developmental dyslexia.Methods:A total of 54 children were enrolled,indadit 27 children with Chinese DD and 27 age-gender-matched normal children.The Test of Gross Motor Development-Third Edition(TGMD-3),and the balance tests from the Movement Assessment Battery for Children(M-ABC)were used to evaluate the children's gross motor development level.Children's reading ability was evaluated by primary school students'literacy test question bank,one-minute reading task,and the Reading Test on Pupils.Results:The overall analysis of motortests showed that the grossmotor total score,locomotor score,object control score,and balance score in the DD group were significantly lower than those in the normal control group(P＜0.05).Logistic regression analysis revealed a negative association between balance scores,locomotor scores,object control scores,TGMD-3 total scores and indi-viduals with dyslexia(OR=3.08,1.35,1.16,1.13,Ps＜0.05).Conclusion:The delayed gross motor development of children is associated with the occurrence of Chinese developmental dyslexia.

Objective:To explore the association between the gross motor development of children and Chi-nese developmental dyslexia.Methods:A total of 54 children were enrolled,indadit 27 children with Chinese DD and 27 age-gender-matched normal children.The Test of Gross Motor Development-Third Edition(TGMD-3),and the balance tests from the Movement Assessment Battery for Children(M-ABC)were used to evaluate the children's gross motor development level.Children's reading ability was evaluated by primary school students'literacy test question bank,one-minute reading task,and the Reading Test on Pupils.Results:The overall analysis of motortests showed that the grossmotor total score,locomotor score,object control score,and balance score in the DD group were significantly lower than those in the normal control group(P＜0.05).Logistic regression analysis revealed a negative association between balance scores,locomotor scores,object control scores,TGMD-3 total scores and indi-viduals with dyslexia(OR=3.08,1.35,1.16,1.13,Ps＜0.05).Conclusion:The delayed gross motor development of children is associated with the occurrence of Chinese developmental dyslexia.

Objective To explore the impact of exercise intervention on the reading abilities of chil-dren with Chinese developmental dyslexia(CDD).Methods Twenty-seven CDD children were recruited from patients of Peking University Sixth Hospital,and randomly divided into a CDD exercise interven-tion group of 14 and a CDD control group of 13.Another 14 age-matched normal children were select-ed into a normal control group.All groups kept daily physical activities in school,while the CDD ex-ercise intervention group additionally underwent 8-week individualized gross and fine motor interven-tion.The literacy,reading fluency and reading comprehension of all groups were evaluated by using"Elementary School Students'Literacy Test and Evaluation Scale",one-minute word reading and ele-mentary school students'reading ability assessment.Results Before the intervention,there were no sig-nificant differences between the exercise intervention and control groups in the literacy level,reading fluency,and reading comprehension(P>0.05),which were all significantly lower than the normal con-trol group(P<0.05).However,after the intervention,significant improvement was observed in the aver-age literacy level,reading fluency,and reading comprehension of the CDD exercise intervention group,and the literacy and reading fluency of the CDD control group,as well as the average literacy level and reading comprehension of the normal control group.Moreover,there were no significant differ-ences between the CDD exercise intervention and control groups in the average literacy level and read-ing fluency score(P>0.05),both significantly lower than the normal control group(P<0.05).Mean-while,the reading comprehension score of the CDD exercise intervention group was significantly higher than the CDD control group(P<0.05),but significantly lower than the normal control group(P<0.05).Conclusion Eight-week targeted gross and fine motor intervention can effectively improve reading abili-ty of DD children,especially their reading comprehension.

ObjectiveTo investigate the developmental characteristics of gross motor skills and executive functions, and the correlation between them in school-age children with attention deficit hyperactivity disorder (ADHD). MethodsFrom November, 2020 to May, 2021, 90 children with ADHD were recruited from Peking University Sixth Hospital and Beijing Haidian Wanquan Primary School, and other 90 children with normal development from this primary school were recruited matched their age and gender. Gross motor skills were assessed with the Test of Gross Motor Development in Children, Third Edition (TGMD-3), and inhibitory control, working memory, and cognitive flexibility were assessed with Stroop Color Words Test (SCWT), Rey-Osterrich Complex Figure Test (ROCFT) and Trail Making Test (TMT), respectively. ResultsThe TGMD-3 score was significantly lower in children with ADHD than in normal children (t = -6.275, P < 0.001), while the test results of SCWT, ROCFT and TMT were worse (|t| ≥ 1.986, P ≤ 0.05). The TGMD-3 score of children with ADHD was negatively correlated with the word sense reaction time (r = -0.261), the number of word sense errors (r = -0.404) and the number of color errors (r = -0.326) (P < 0.05), positively correlated with the delayed structural memory scores (r = 0.228) (P < 0.05), and negatively correlated with the TMT-A reaction time (r = -0.255), the number of TMT-A errors (r = -0.329), TMT-B reaction time (r = -0.214) and the number of TMT-B errors (r = -0.474) (P < 0.05). Stratified linear regression analyses showed that the TGMD-3 score of children with ADHD was significant only in predicting test results for inhibitory control and cognitive flexibility (P < 0.05), with explanations of 8.7% and 22.5%, respectively. ConclusionDevelopments of both gross motor skills and executive function delay in children with ADHD, and there is a relation between them, especially the level of gross motor skills relating to the developments of inhibitory control and cognitive flexibility.

Objective To observe the electromyography characteristics of children's handwriting with attention deficit hyperactivity disorder(ADHD),and explore its electrophysiological mechanism,so as to provide an objective basis for developing non-pharmacological treatment for such children.Methods Between September 2021 and April 2022,29 ADHD children were recruited from an ordinary public primary school and the psychiatric clinic of a class-3 grade-A hospital in Beijing.Among them,25 were boys and 4 were girls,with an average age of 8.21±1.78 years.Meanwhile,23 male and 5 fe-male healthy counterparts were selected with the age gap no more than 6 months.The Delsys wireless surface EMG system was used to collect the electromyographic signals of the abductor pollicis breve,the first dorsal interosseous muscle,the flexor radial carpi motor and the extensor finger muscles dur-ing their writing tasks such as tracing trajectories,writing Arabic numerals 0-9,26 small and capital English letters,Chinese characters one to ten and"Yong".The percentage of the averaged electromyog-raphy(AEMG)of a muscle in the sum value of all measured muscles,and the coefficient of differ-ence were selected to evaluate the muscle contribution rate and the consistency of exertion,respective-ly.Moreover,the independent sample t-test was employed to compare the two different groups with the significance set at α=0.05.Results There was a significant difference in the muscle contribution of abductor pollicis breve and first dorsal interosseous muscles when writing Arabic numerals and that of abductor pollicis breve muscles when writing Chinese characters between ADHD children(27.29%,25.58%and 27.53%)and their healthy counterparts(42.87%,19.96%and 37.13%)(P<0.05).Most muscle differentiation coefficients of ADHD children were higher than 100%,with that of the domi-nant hand radial wrist flexor muscle reaching 270%in the trajectory tracing task.Conclusion Accord-ing to the characteristics of EMG signals,school-age ADHD children show an immature writing pat-tern,including poor stability of writing-related muscles,insufficient control of small finger muscle groups,poor control of hand coordination,and insufficient muscle inhibition of non-dominant hand.It is recommended to conduct the electromyoelectric assessment of handwriting movements in ADHD chil-dren,so as to carry out targeted intervention at an early stage.

ObjectiveTo explore the characteristics of fine motor skills of school-age children with attention deficit hyperactivity disorder (ADHD) in different sexes. MethodsFrom April, 2021 to April, 2023, 66 ADHD children from grades one to four in Beijing Haidian Wanquan Primary School were screened by psychiatrists, and other 69 ADHD children were recruited from hospitals and patient groups of WeChat, accounting to 135 ADHD children. Meanwhile, a total of 135 typically developed (TD) children matched with sex and age (< 0.5 year) were recruited from the same primary school as controls. They were assessed with Movement Assessment Battery for Children (MABC-2) four subtests of manual dexterit. ResultsAfter controlling age, the subtest scores and the total score of fine motor of MABC-2 were less in ADHD boys and girls than in the TD boys and girls (P < 0.05). The main effect of sex was significant on the subtest scores and the total score of fine motor for ADHD children (F > 5.133, P < 0.05), and they were less in the boy than in the girls (P < 0.05). ConclusionThe development of fine motor delays in school-aged ADHD children, especially for the boys.

Objective:To evaluate the changes of peripapillary retinal and choroid thickness of tail-suspension rats in simulated weightless.Methods:Sixty rats were divided into 2 groups: control group (15 rats) and tail-suspension group (45 rats). The rats in tail-suspension group were tested by -30° tail suspension to simulate the effect of weightlessness for establishing model. The peripapillary retinal thickness of the rats were measured before and after 4- and 8-week tail suspension by enhanced depth imaging-optical coherence tomography (EDI-OCT). The choroid thickness of the rats were measured before and after 4-, 8-, 10-, and 12-week tail-suspension by EDI-OCT.Results:There was a significant difference in the peripapillary retinal thickness among the groups with different suspension time ( F=30.89, P<0.001), and the thickness showed a downward trend with the extension of the tail suspension time. After 8 weeks of tail-suspension, there was a significant difference in the peripapillary retinal thickness between the tail-suspension group and the control group ( t=5.73, P<0.001). After 4, 8, 10, and 12 weeks of tail-suspension, there were significant differences in the choroidal thickness of the rats between the tail-suspension group and the control group ( t=6.32, 12.78, 9.69, 6.39, all P<0.001); there was a significant difference in the choroidal thickness of the rats with different suspension time ( F=51.08, P<0.001). With the time of the tail suspension, the choroidal thickness and its changes compared with before tail suspension showed an upward trend, and reached peak after 8 weeks and then slightly decreased. Conclusions:With the extension of tail-suspension time, the changes of peripapillary retinal thickness of the tail-suspension rats generally show a downward trend, and the changes of choroidal thickness generally increased, and decreased slightly after reaching peak.

Objective:To evaluate the changes of peripapillary retinal and choroid thickness of tail-suspension rats in simulated weightless.Methods:Sixty rats were divided into 2 groups: control group (15 rats) and tail-suspension group (45 rats). The rats in tail-suspension group were tested by -30° tail suspension to simulate the effect of weightlessness for establishing model. The peripapillary retinal thickness of the rats were measured before and after 4- and 8-week tail suspension by enhanced depth imaging-optical coherence tomography (EDI-OCT). The choroid thickness of the rats were measured before and after 4-, 8-, 10-, and 12-week tail-suspension by EDI-OCT.Results:There was a significant difference in the peripapillary retinal thickness among the groups with different suspension time ( F=30.89, P<0.001), and the thickness showed a downward trend with the extension of the tail suspension time. After 8 weeks of tail-suspension, there was a significant difference in the peripapillary retinal thickness between the tail-suspension group and the control group ( t=5.73, P<0.001). After 4, 8, 10, and 12 weeks of tail-suspension, there were significant differences in the choroidal thickness of the rats between the tail-suspension group and the control group ( t=6.32, 12.78, 9.69, 6.39, all P<0.001); there was a significant difference in the choroidal thickness of the rats with different suspension time ( F=51.08, P<0.001). With the time of the tail suspension, the choroidal thickness and its changes compared with before tail suspension showed an upward trend, and reached peak after 8 weeks and then slightly decreased. Conclusions:With the extension of tail-suspension time, the changes of peripapillary retinal thickness of the tail-suspension rats generally show a downward trend, and the changes of choroidal thickness generally increased, and decreased slightly after reaching peak.