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Objective The staffs of biosafety level 3 laboratories (BSL-3) face with the stress of handling highly pathogenic microbs and special laboratory environment.The job stress may result in accidents in the laboratory as negative factor for the risk control.The research may provide support for the control of risk in biosafety laboratories.Methods In order to assess the job stress in the staff in BSL-3 laboratory, we modified “the Chinese simple job stress questionnaire”based on the theory of the JDC mode and ERI mode, and an investigation was carried out.The present study included the staffs (87 employees) from six BSL-3 laboratories located in five provinces ( Shanghai, Zhejiang, Jiangsu, Fujian and Wuhan) .Results Analysis of the data indicates that variables of age, working years, job duties, manipulating of animals, type of microorganisms and transmission route have a significant influence on the level of job stress in BSL-3 laboratory.Conclusion The BSL-3 laboratory staff in higher stress level have the characteristicses:20-39 years old, short work years, regular staff, operating on air-borne microbiology, manipulating of animals and operating on one more microbiology.
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Objective To investigate the role of CD4 ~+ CD25~+ regulatory T lymphocytes (Treg)in modulating the cellular immune response and pathogenesis of murine pulmonary tuberculosis.Methods Inactivation of Treg was achieved by intraperitoneal injection anti-CD25 (clone PC61,50 μ/mouse) in PC61 group, and rat-IgG (50 μ/mouse) was injected intraperitoneally in control group. All the mice were inoculated intravenously with H37Rv 0. 1 mL (1 × 10~6 CFU) 3 days after Treg inactivation. The effects of Treg inactivation in different tissues were analyzed by flow cytometry. The cellular immune response, pulmonary histopathology and bacterial load were determined in vitro at different time points. The data were compared using homogeneity of variance F test and non-paired t test. Results In spleen, the percentages of Treg/CD4 T lymphocytes in PC61 group and control group were (21. 13± 3. 58)% and (30. 42± 4. 20)%, respectively at day 10 of inoculation (t = 2. 38, P < 0. 05), and those were (16. 12 ± 1. 26)% and ( 17. 34± 1. 62)%,respectively at day 30 of inoculation (t = 0. 84,P>0. 05). The percentages of Foxp3~+/CD4~+ T lymphocytes in PC61 group and control group were (32. 07 ± 3. 95)% and (60. 55 ± 5. 48)%,respectively at day 10 of inoculation (t = 5. 96, P<0. 05). Similar results were achieved in the peripheral blood. Bacillus calmette-guerin (BCG)-specific 1L-17 (ng/L) secreted by murine spleen cells in PC61 group and control group at day 10, 30 and 60 of inoculation were 5. 1± 0.9 vs 0, 43. 1± 10.0 vs5. 9± 2. 8 and 124.8 ± 5.8 vs 102. 5±8. 1, respectively (t = 7. 90, t=5. 10,t = 3. 19; all P<0.05); those of BCG-specific IFN-γ (ng/L) were 28. 4 ± 8. 2 vs 4. 0±1. 3, 685. 9± 128. 6 vs418. 7±20.4 and 310.9±119. 7 vs 32. 8±7. 5, respectively(tO = 4. 21,t = 8. 43, t = 3. 27; all P<0.05);those of TNF-a (ng/L) were 38. 6±5.0 vs 16. 3±4. 0, 112. 9 ±12. 3 vs 71. 5±12. 6 and 86. 2±8. 2vs0, respectively(t = 4. 95, t=3. 33,t/=14.8; all P<0. 05). The lung bacterial load at day 10 of inoculation in PC61 group was lower than that in control group (t = 4. 63, P < 0. 01), but the differences were not significant thereafter. The changes of lung histopathology at late stage of infection (day 120) in PC61 group were less severe than those in control group. Conclusions Murine Tregs increase dramatically after Mycobacterium tuberculosis infection. Treg could inhibit the specific cellular immunity against Mycobacterium tuberculosis, and therefore, may facilitate the persistent infection of Mycobacterium tuberculosis and development of tuberculosis.
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AIM: This study was designed to investigate the effects of sodium restriction and sodium supplementation on the expression of angiotensinogen mRNA in myocardium of rats with congestive heart failure(CHF).METHODS: Radioimmunassay and in situ hybridization techniques were used to determine the angiotensin Ⅱ(AngⅡ)contents and the expression of angiotensinogen(ANG)mRNA in myocardium, respectively.RESULTS: In sodium restricted group, the plasma sodium was obviously lower than that in CHF group(P
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AIM: To investigate the expression of angiotensinogen (ANG)mRNA and the changes of AngⅡ content in rat anterior pituitary during acute stress.METHODS: The expression of ANG mRNA was determined using in situ hybridization technique, and the AngⅡ content were determined by RIA.RESULTS: The ANG mRNA expression and AngⅡ content were significantly increased, and ANG mRNA was increased more significantly than AngⅡ content. CONCLUSION: The local renin-angiotensin system (RAS) in anterior pituitary is obviously activated during stress, which strongly supports the view that local RAS contributes to stress reaction.