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 investigate the effect of LncRNA GAPLINC on the cell proliferation of RA-FLSs. MethodsRA-FLSs were cultured from synovial specimens. The expression of LncRNA GAPLINC in RA-FLSs and trauma-FLSs groups was detected by qRCR. GAPLINC suppression was transfected by siRNA and the inhibition efficiency was detected by qRCR. Flow cytometry was adopted to determine the change of cell growth and cell cycle distribution. 【ResμLts】 The expression of LncRNA GAPLINC was significantly higher in RA-FLSs than that of the trauma-FLSs （P<0.05）.Transfection of GAPLINC-siRNA significantly decreased the expression of LncRNA GAPLINC. GAPLINC silence in RA-FLSs revealed significant inhibition in cell proliferation which was showed by the reduced cell number in S phase（P<0.05）. Moreover， flow cytometry assay showed GAPIINC-siRNA treatment group had an accumμLation of cells in the G0/G1 phase and decreased RA-FLSs in the S and G2/M phase（P<0.05）. After GAPLINC knockdown， mRNA and protein levels of Cyclin D1 and PCNA， which were positively correlated with proliferative phenotype， were decreased （P<0.05）， while p21， which was negatively correlated with proliferative phenotype， was up-regμLated （P<0.05）. ConclusionsThe mRNA expression of GAPLINC was higher in RA-FLSs compared with trauma-FLSs ，which was statistically significant（P<0.05）. The silence of LncRNA GAPLINC coμLd significantly inhibit RA-FLSs cell growth and suppress the cell cycle transformation， which suggests that GAPLINC may play a role in the regμLation of proliferation of RA-FLSs， leading to synovial hyperplasia and contributing to RA progression.