Objective:This study aims to investigate the prevalence of internet addiction, morningness-eveningness preference of sleep-wake chronotype, and sleep quality and the correlates of internet addition among first-year undergraduate students.Methods:The newly admitted undergraduates ( n=9 157) of a comprehensive university in 2019 were invited to participate in an online survey from September 2019 to December 2019. The Young′s 20-item Internet Addiction Test, the Pittsburgh sleep quality index, and the Morningness-Eveningness Questionnaire (MEQ) were used to measure internet addiction, sleep quality, and the types of morningness-eveningness preference respectively. Logistic regression analysis was used to analyze factors independently related to internet addiction with demographic variables (i.e., gender and age), sleep problems, and morningness-eveningness preference adjusted. Results:A total of 7 457 (81.4%) newly admitted undergraduates completed the questionnaires. The prevalence of internet addiction in the total sample was 8.86% (661/7 457), while the corresponding figures were 10.04% (348/3 466) in female students and 7.84% (313/3 991) in male students. The prevalence of sleep problems was 11.73% (875/7 457). For chronotype, the prevalence of evening type, intermediate type, and morning type was 54.73% (4 081/7 457), 43.02% (3 208/7 457) and 2.25% (168/7 457) respectively. After adjusting the interaction of related factors in the logistic regression analysis, being female ( OR=1.26), having sleep quality ( OR=4.12), and having sleep-wake chronotype of intermediate type ( OR=0.37) and morning type ( OR=0.24) were independently associated with internet addiction. Conclusions:Female students had higher prevalence of internet addiction than male students. Majority of students had a chronotype of intermediate or evening type. The sleep-wake chronotype was independently associated with internet addiction after controlling sleep quality, which indicated that sleep biological rhythm may be involved in the mechanism of the occurrence of internet addiction.

Objective:This study aims to investigate the prevalence of internet addiction, morningness-eveningness preference of sleep-wake chronotype, and sleep quality and the correlates of internet addition among first-year undergraduate students.Methods:The newly admitted undergraduates ( n=9 157) of a comprehensive university in 2019 were invited to participate in an online survey from September 2019 to December 2019. The Young′s 20-item Internet Addiction Test, the Pittsburgh sleep quality index, and the Morningness-Eveningness Questionnaire (MEQ) were used to measure internet addiction, sleep quality, and the types of morningness-eveningness preference respectively. Logistic regression analysis was used to analyze factors independently related to internet addiction with demographic variables (i.e., gender and age), sleep problems, and morningness-eveningness preference adjusted. Results:A total of 7 457 (81.4%) newly admitted undergraduates completed the questionnaires. The prevalence of internet addiction in the total sample was 8.86% (661/7 457), while the corresponding figures were 10.04% (348/3 466) in female students and 7.84% (313/3 991) in male students. The prevalence of sleep problems was 11.73% (875/7 457). For chronotype, the prevalence of evening type, intermediate type, and morning type was 54.73% (4 081/7 457), 43.02% (3 208/7 457) and 2.25% (168/7 457) respectively. After adjusting the interaction of related factors in the logistic regression analysis, being female ( OR=1.26), having sleep quality ( OR=4.12), and having sleep-wake chronotype of intermediate type ( OR=0.37) and morning type ( OR=0.24) were independently associated with internet addiction. Conclusions:Female students had higher prevalence of internet addiction than male students. Majority of students had a chronotype of intermediate or evening type. The sleep-wake chronotype was independently associated with internet addiction after controlling sleep quality, which indicated that sleep biological rhythm may be involved in the mechanism of the occurrence of internet addiction.

Objective To investigate the clinical characteristics of children with medulloblastoma (MB). Methods The correlations amongst MB histopathological subtype,age at diagnosis,gender,primary tumor locations, relapsed tumor and relapsed tumor locations were analyzed retrospectively in 83 children who were diagnosed as MB by histopathology subtypes from February 2012 to April 2015 in Beijing Shijitan Hospital Affiliated to Capital Medical Uni-versity.The data was conducted by using SPSS 22.0 statistical software.Results Among the 83 cases (53 boys and 30 girls),there were 14 patients younger than 3 years old (9 boys and 5 girls)and 69 patients (44 boys and 25 girls)ol-der than 3 years old,including 28 relapsed (19 boys and 9 girls)and 55 non -relapsed cases (34 boys and 21 girls). The median age was 80.2 (13.1 -184.7)months at diagnosis.Of these 83 cases,48.2% (40 /83 cases)was classic medulloblastoma (CMB)(2 cases less than 3 years old),24.1 % (20 /83 cases)was desmoplastic /nodular medullo-blastoma (DMB)(6 cases less than 3 years old),12.1 % (10 /83 cases)was large cell/anaplastic medulloblastoma (LC /AMB)(1 case less than 3 years old),3.6% (3 /83 cases)was extensive nodular medulloblastoma (MBEN)(1 case less than 3 years old),and 12.1 % (10 /83 cases)(3 cases less than 3 years old)was mixed subtype.The rela-tionships between age at diagnosis and histopathological subtype,gender and primary tumor location were all statistically significant (χ2 =0.014,0.013,all P <0.05).Conclusions The incidence of boys with MB is higher than girls.CMB is the main histopathologic subtype in children over 3 years old.The primary tumor location involving the cerebellar vermis or cerebellar vermis and the fourth ventricle is higher in girls with MB.The primary tumor location involving the fourth ventricle,the fourth ventricle and other parts of the central nervous system,Cerebellar vermis and other parts of the central nervous system or other parts of the central nervous system is higher in boys with MB.

Objective To investigate the protective effect of Ebselen on mitochondrial damage and its influence to Cytochrome C expression and the neuronal apoptosis after spinal cord injury in rats. Methods Sixty adult SD rats were ran-domly divided into 5 groups (12 each group). Spinal cord injury model was made using Allen's method. Sham operation group received only laminectomy;SCI group received laminectomy and spinal trauma;Saline group received saline injection intraperitoneally (0.1%DMSO) after injury;methylprednisolone group received 30 mg/kg methylprednisolone injection intra-peritoneally, ebselen group received 10 mg/kg ebselen injection intraperitoneally. The malonaldehyde (MDA) and glutathi-one (GSH)level at the injured sites of the spinal cord were detected 24 hours after trauma, and the expression level of Cyto-chrome C was also observed. Finally, neuronal apoptosis was identified by TUNEL staining. Results MDA level in the Eb-selen group was significantly lower than that in the SCI group, and GSH level was significantly elevated in the Ebselen group compared with SCI group (P<0.01). Expression of Cytochrome C in Ebselen group was lower than that in SCI group shown by Western blot, and the neuronal apoptosis in Ebselen group reduced significantly too compared with SCI group (P<0.01). Conclusion Ebselen can alleviate peroxidation,prohibit expression of Cytochrome C and inhibit neuronal apoptosis,thus it shows a protective effect to experimental acute SCI.