ABSTRACT
Objective@#To explore the effects of cigarette smoke exposure during pregnancy on the quality of oocytes and the whole genome DNA methylation in the offspring of female mice during the period of germinal vesicle (GV) .@*Methods@#The pregnant 7 d mice were divided into 3 groups, exposure on the 0, 0.5, 1 lit cigarettes cabinet (volume 18 L) , at 9 am and 3 pm for 1 h twice daily, until delivery. When the mice were 6 weeks old, the organ index and the number of follicles in the ovary were detected by weighing and making HE stained sections. GV stage oocytes were obtained by Hoechst 33342 staining and indirect immunofluorescence to detect the quality of oocytes, chromatin configuration and whole genome DNA methylation level.@*Results@#Compared with the control group and low dose group, the offspring ovarian organ index of female mice in the high dose group decreased, the difference was statistically significant (P<0.05) . Compared with the control group, the number of follicular oocytes in low dose group and high dose group female mice offspring decreased, the zona pellucida oocytes diameter decreased, and the zona pellucida thickness increased, the differences were statistical significance (P<0.05) . Compared with control group and low dose group, in the high dose group, the oocytes nucleus diameter of the female mice offspring decreased, the proportion of nucleolus surrounded type chromatin configuration (SN) decreased, and the proportion of nucleoil not surrounded type (NSN) increased, the relative fluorescence intensity of 5MeC decreased, the differences were statistically significant (P<0.05) .@*Conclusion@#Exposure to cigarette smoke during pregnancy may reduce indicators of offspring ovarian organ index, female rat follicle number and oocyte quality change, the high dose group can lead to oocyte chromatin structure and DNA methylation level anomaly.
ABSTRACT
To better understand the molecular characterization ,pathogenesis ,origin ,and evolutionary relationship of the first human-infecting H6N1 influenza virus ,the dataset was downloaded from the Flu and GISAID databases ,and the phy-logenetic trees were reconstructed by maximum likelihood (ML) ,maximum parsimony (MP) and Bayesian inference (BI) . Furthermore ,the evolution rate ,the most recent common ancestor (TMRCA) ,variable sites ,glycosylation sites ,cleavage sites and other some molecular features were also analyzed by bioinformatic means .The results indicated that the HA gene fell into an individual clade with other three H6N1 virus strains isolated from chicken .TMRCA was in 2002 ,and the cluster had a higher evolution rate .The molecular features revealed the HA protein had 5 N-glycosylation sites ,2 O-glycosylation sites and 2 unique variable sites .The cleavage sites had only one basic amino acid and suggested that the human-infecting H6N1 virus strain was low pathogenic .However ,because of the higher substitution rate and viral reassortment ,people should pay more attention .