Objective To study the influence of pregnant rats' prenatal chronic stress (PS) on learning and memory of their offspring rats and its possible molecular mechanisms.Methods Pregnant females were individually restrained for 45 min 3 times a day during pregnancy from day 14 to day 21.Control pregnant females were left undisturbed in their home cages.The rat offsprings were randomly assigned to PS group or control group.Males and females were kept for the study separately.The learning and memory of the developing rat offspring in the Morris water maze were examined.The basal levels of corticosterone (COR) and adreno-cortico-tropic-hormone (ACTH) were analyzed by using radioimmunoassay.The Golgi-Cox impregnation technique was used to compare density and morphology of the CA1 hippocampal dendritic spines.Results The escape latency (EL) to find the platform in the control group was significantly less than that in the PS group in female rat offspring (F =4.533,P ＜ 0.05),and the difference was statistically significant on the 5th day (t =2.788,P ＜ 0.01).EL to find the platform in the control group was significantly less than that in the PS group in male rat offspring (F =6.101,P ＜0.05),and the difference was statistically significant on the second day (t =3.051,P ＜ 0.01).In the space exploration experiments of the water maze,the retention time observed for the control group and the PS group in the goal quadrant was similar(P ＞ 0.05).The basal levels of the serum COR in the PS group were higher than those in the control group of female rat offspring(t =3.658,P ＜ 0.01) and the basal levels of the serum ACTH in the PS group were higher than those in the control group of male rat offsprings(t =2.319,P ＜ 0.05).A simplified pattern was observed in the CA1 hippocampal dendritic spines in the PS group,showing a less extent of dendritic arborization and the density was significantly lower than that in the control group(t =-3.072,P ＜ 0.01).Conclusions Altered function of the hypothalamic-pituitary-adrenal axis in the offspring mediates the cognitive alterations observed following prenatal stress should to be associated with the lower density and simplified pattern of CA1 dendritic spines.

OBJECTIVETo investigate the epidemiological characteristics of measles cases of new genotype D8 in Beijing from January to June, 2013.

METHODSEpidemiological survey and descriptive analysis was conducted.

RESULTS661 suspected measles were reported from January to June, 2013. 416 were confirmed measles cases by serology and etiology detection. 28 measles cases were caused by genotype D8 measles virus by genotype identification. There were 2 measles outbreak including 14 cases and 14 sporadic cases. The incidence peak was during April and May. 25 cases (89.3%, 25/28) occurred in downtown and suburban districts. 22 cases (78.5%, 22/28) were adults aged 15-39 years and 19 cases (67.9%, 19/28) were migrant population. 12 cases (85.7%, 12/14) in outbreak were migrant population working in clothing sales. There was epidemiological association between 2 outbreaks.

CONCLUSIONMeasles cases of genotype D8 were found for the first time in Beijing. Genotype D8 virus mainly infected migrant adults and caused local outbreak and endemic.

Adolescent ; Adult ; China ; epidemiology ; Disease Outbreaks ; Female ; Genotype ; Humans ; Incidence ; Male ; Measles ; epidemiology ; virology ; Measles virus ; genetics