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Objective@#To analyze the epidemiological characteristics and influencing factors of norovirus aggregation in primary and secondary schools in Haidian District of Beijing from 2015 to 2018,and to provide scientific basis for the prevention and control of school aggregation epidemic situation.@*Methods@#An epidemiological method was used to analyze the epidemic characteristics of norovirus aggregation in the primary and secondary schools in Haidian District of Beijing from January 2015 to December 2018. Multivariate Logistic was used to analyze the influencing factors of norovirus aggregation.@*Results@#A total of 74 cases of norovirus aggregation in primary and secondary schools in Haidian District of Beijing from 2015 to 2018 were reported, involving 52 primary and secondary schools. Totally 1 291 suspected cases and a median of 12.5 cases of single epidemic were reported. Winter and spring were high incidence season. There was significant difference in the incidence rate of epidemic situation in primary and secondary schools(χ2=98.82, P<0.01). There was significant difference in the incidence rate between men and women(χ2=55.56, P<0.01). A total of 648 samples and 486 positive samples were collected, with a positive rate of 75.00%, mainly GⅡ virus, accounting for 87.45%. Multivariate Logistic regression showed that the scale of school(>2 000，1 000~2 000), student’s hand hygiene habit,requirement for medical care after the outbreak is the influence factor of the outbreak(OR=3.78，2.95，8.25，2.88).@*Conclusion@#Poor hand hygiene habits are the most important risk factors for the outbreak, so schools and parents should cultivate children to develop good hygiene habits of washing hands before and after meals, and timely isolation of cases found in schools is also an important measure to prevent and control the epidemic.
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Background: Z-guggulsterone, an active compound extracted from the gum resin of the tree Commiphora mukul, has been shown to improve animal memory deficits via activating the brain-derived neurotrophic factor signaling pathway. Here, we investigated the antidepressant-like effect of Z-guggulsterone in a chronic unpredictable stress mouse model of depression. Methods: The effects of Z-guggulsterone were assessed in mice with the tail suspension test and forced swimming test. Z-guggulsterone was also investigated in the chronic unpredictable stress model of depression with fluoxetine as the positive control. Changes in hippocampal neurogenesis as well as the brain-derived neurotrophic factor signaling pathway after chronic unpredictable stress/Z-guggulsterone treatment were investigated. The tryptophan hydroxylase inhibitor and the tyrosine kinase B inhibitor were also used to explore the antidepressant-like mechanisms of Z-guggulsterone. Results: Z-guggulsterone (10, 30 mg/kg) administration protected the mice against the chronic unpredictable stress-induced increases in the immobile time in the tail suspension test and forced swimming test and also reversed the reduction in sucrose intake in sucrose preference experiment. Z-guggulsterone (10, 30 mg/kg) administration prevented the reductions in brain-derived neurotrophic factor protein expression levels as well as the phosphorylation levels of cAMP response element binding protein, extracellular signal-regulated kinase 1/2, and protein kinase B in the hippocampus and cortex induced by chronic unpredictable stress. Z-guggulsterone (10, 30 mg/kg) treatment also improved hippocampal neurogenesis in chronic unpredictable stress-treated mice. Blockade of the brain-derived neurotrophic factor signal, but not the monoaminergic system, attenuated the antidepressant-like effects of Z-guggulsterone. Conclusions: Z-guggulsterone exhibits antidepressant activity via activation of the brain-derived neurotrophic factor signaling pathway and upregulation of hippocampal neurogenesis.
