Objective To investigate the influence of murine cytomegalovirus on the expansion of CD+CD25+ Foxp3+ regulatory T cell (Treg) and the activation of CD4+ CD25+Foxp3 - effector T cell (TE) in vivo. Methods Forty-two BALB/c mice were intraperitoneally inoculated with appropriate amount ofMCMV Smith strain for establishing the model of infection, another 42 mice served as mocked-infected con-trois. Day 28 post MCMV infection was determined to be the demarcation point of the acute and chronic in- fection based on the viral load of major visceral organs. On day 1,3, 7, 14, 28, 45 and 60 post infection, splenocytes were prepared by means of routine method. The proportions of CD4+CD25+ Foxp3+Treg and CD4+CD25+Foxp3- activated TE in T lymphocyte were measured by flow cytometry. Results The propor- tion of CD+CD25+ Foxp3+ T cells in T lymphocytes was persistently suppressed since day 7 post infection, and fell to the lowest level on day 28 post infection (P <0.01), then zoomed and reached the peak value on day 60 post infection (P < 0.05). CD4+CD25+ Foxp3 - TE proportion was up to the highest on day 3 post infection(P < 0. 01), then suppressed and in significantly lower level since day 45 post infection (P < 0.05). Treg/CD+TE ratio was in lower level on day 3 to 14 post infection(P <0.05) ; but on day 45 and day 60 post infection Treg/CD+ TE ratio was markedly increased (P < 0.05). Conclusion MCMV infec- tion can increase the CD+CD25+Foxp3+ Treg proportion, and inhibit CD4+T cells activation in chronic in- fection phase, which is likely to suppress the function of antiviral immunity in the infected host to cause a persistent latent infection.

AIM:To investigate the changes of brain-derived neruotrophic factor(BDNF),tyrosine kinase B(TrkB) in rat cortex and hippocampus with chronic immobilization stress and the influence of three Chinese formulas(Xiaoyaosan,Sijunzitang,Jinkuishenqiwan) on them.METHODS:Chronic immobilization stress method(180 min daily,repeated 7 days or 21 days) was taken,and the changes of BDNF,TrkB in rat forehead cortex and hippocampus CA1 were measured by immunohistochemistry integrated image analysis.RESULTS:The contents of BDNF in rat forehead cortex and hippocampus CA1 were obviously lower in the model group of 7 days and 21 days than those in the normal control group(P

OBJECTIVE: To explore the influencing factors of depressive symptom of employees in a mould-producing enterprises using two occupational stress models. METHODS: A total of 457 employees in a mould-producing enterprise were selected as study subjects using cluster sampling method. The Center for Epidemiological Study-Depression Scale, the Chinese version of Job Demand Content Questionnaire and the Effort-Reward Imbalance Questionnaire were used to investigate the level of depressive symptom and occupational stress by the job demand control(JDC) model and effort reward imbalance(ERI) model. RESULTS: Among the 457 employees, the median score of depressive symptom was 11.00, the detection rate of depressive symptom in the subjects was 23.4%(107/457). The incidence of occupational stress by the JDC and ERI models was 78.3%(358/457) and 62.6%(286/457), respectively. The rate of depressive symptom was statistically higher in the high occupational stress group than that of the low occupational stress group by the ERI model(26.6% vs 18.1%, P<0.05). The multivariate logistic regression analysis showed that both marital status and monthly income were influencing factors of depressive symptom by the JDC model(P<0.05). The marital status, monthly income and occupational stress were influencing factors of depressive symptom by the ERI model(P<0.05). The risk of depressive symptom was statistically higher in the high occupational stress group than that of the low occupational stress group(P<0.05). CONCLUSION: Employees in mould-producing enterprise have some depressive symptom. The marital status, monthly income and occupational stress by the ERI model are the main influencing factors of depressive symptom.