Objective:To evaluate the effect of Parkinson′s disease factor on the sedative efficacy of dexmedetomidine.Methods:The patients of either sex, aged 45-64 yr, of American Society of Anesthesiologists Physical Status classification Ⅱor Ⅲ, with body mass index of 18.5-30.0 kg/m 2, undergoing non-intracranial space-occupying lesions in neurosurgery, were selected.Patients were divided into control group (group C) and Parkinson′s disease group (group P) according to whether they had Parkinson′s disease or not.The ED 50 of dexmedetomidine was determined by using the Dixon′s up-and-down method.The initial dose of dexmedetomidine was 0.5 μg/kg in both groups, and each time the concentration increased/decreased by 0.05 μg/kg in the next patient, which was repeated until 7th independent crossover pair (loss of consciousness) appeared, and then the test was ended.The ED 50 and 95% confidence interval of dexmedetomidine inducing loss of consciousness were calculated using the probit test in a Logistic regression model.Hypertension, hypotension, bradycardia and nausea and vomiting were recorded. Results:Compared with group C, the ED 50 of dexmedetomidine inducing loss of consciousness was significantly increased in group P ( P<0.05), and no significant change was found in the incidence of adverse reactions in group P ( P>0.05). Conclusions:Parkinson′s disease factor can decrease the sedative efficacy of dexmedetomidine.

Objective: To investigate the relationship between after-school schedule and bone mineral density in middle-school students in Shanghai, to provide a reference for taking targeted measures. Methods: From November 2017 to April 2018，eighteen classes of six middle schools in Shanghai (from urban districts, urban-suburb combined districts and suburban districts, respectively) were selected based on cluster random sampling. In each school, 2-4 classes were further randomly chosen in the 6th grade. Questionnaires were completed by 518 students and their parents, as well as physical examination and bone mineral density assessment. Results: The average time spent on after-school academic learning during weekends was 4.0 (IQR: 2.0, 6.0) h. The Z-score of bone density was 0.3 (IQR: -0.7, 1.0). The smooth curve fit model showed a non-linear relationship between after-school academic learning time during weekends and the Z-scores of bone mineral densities. A two-stage multiple linear regression analysis was further applied according to the fit results, and the results showed that when total afterschool academic learning time <4.5 hours during weekends, the learning time was inversely correlated with the bone density Z-scores (β=-0.11,P=0.01), and when the learning time ≥4.5 hours, there was no significant correlation between the learning time and bone density Z-scores (β=0.02, P=0.65). Parent and student questionnaires showed that there was a non-linear relationship between students’ daily time spent on outdoor sports-related activities and bone density Z-scores. When time spent on the outdoor activities ≥45 minutes per day, outdoor activities were positively correlated with bone density Z-scores (P<0.05). However, when the time spent on outdoor activities <45 minutes per day, there was no significant relationship between outdoor activities and bone density Z-scores (P>0.05). Conclusion Too much time on after-school academic learning during weekends or limited time on outdoor activities are both related to impaired bone mineral densities. Therefore, a reasonable after-school schedule for middle-school students is important for physical development, especially during weekends.

BackgroundPrevious studies have identified a close relationship among psychological neglect and abuse， negative affect， different stages of adolescence， and suicidal ideation. However， the mechanisms underlying the impact of psychological abuse and neglect on suicidal ideation among left-behind adolescents remain unclear， and this field of research is still in its relative infancy. ObjectiveTo explore the relationship between psychological neglect/abuse and suicidal ideation among left-behind adolescents， as well as the mediating role of negative affect and the moderating effect of different stages of adolescence， so as to provide insights for preventing and intervening suicidal ideation in this population. MethodsFrom November 2021 to May 2022， a cluster random sampling technique was utilized to select 2 309 left-behind adolescents in western China. Assessments were conducted using the Child Psychological Abuse and Neglect Scale （CPANS）， the Positive and Negative Suicide Ideation （PANSI） and the Positive and Negative Affect Schedule for Children （PANAS-C）. Spearman correlation coefficients were calculated across all samples， and Process 4.1 was employed to test the mediating role of negative affect and the moderating role of different stages of adolescence in the pathway linking psychological abuse/neglect to suicidal ideation. ResultsA total of 2 119 left-behind adolescents （mean age： 14.94±1.20 years） completed the study， with males comprising 51.34% （1 088/2 119） and females 48.66% （1 031/2 119）.Among left-behind adolescents， scores on CPANS psychological neglect subscale showed positive correlations with both psychological abuse subscale scores and PANAS-C negative affect subscale scores （r=0.446， 0.496， P<0.01）. Additionally， CPANS psychological neglect and psychological abuse subscale scores were also positively correlated with PANSI scores （r=0.487， 0.508， P<0.01）. Furthermore， PANAS-C negative affect subscale scores demonstrated a positive correlation with PANSI scores （r=0.499， P<0.01）. Negative affect partially mediated the relationship between psychological abuse/psychological neglect and suicidal ideation， with effect sizes of 0.166 （95% CI： 0.141~0.191） and 0.131 （95% CI： 0.112~0.152）. Different stages of adolescence moderated the latter part （negative emotion → suicidal ideation） of the indirect mediation path from psychological neglect to suicidal ideation through negative affect （β=-0.066， P<0.01）. ConclusionBoth psychological neglect and psychological abuse may influence suicidal ideation among left-behind adolescents via negative affect. Moreover， different stages of adolescence may moderate the indirect path from psychological neglect to suicide ideation through negative affect.