OBJECTIVE To study the clinical feature of nosocomial infection and analyze the correlative reasons,to offer the scientific theory basis for preventing and controlling the nosocomial infection. METHODS A retrospective survey was undertaken in the data of hospitalized cases during 2007. RESULTS Totally 2325 nosocomial infections in 54 505 patients were analyzed in 2007.The infection rate of nosocomial infection was 4.27%;the highest infection rate was in ICU(33.57%);the infection sites were different in distinct departments and the most common infection site was lower respiratory tract(27.19%);among pathogens isolated from nosocomial infection cases,48.05% of them were Gram-negatives,23.25% were virus,14.45% were fungi,and 14.15% were Gram-positives;the infection rate was diverse in different months. CONCLUSIONS Nosocomial infection rate is related to different underlying diseases;there are many effective actions to reduce the nosocomial infection,such as strengthening the nosocomial infection management,using the antibacterial drugs reasonably and preventing communicable diseases prevalence.

AIM: To observe the change of nitric oxide (NO) generation system in the vascular adventitia, media and intima in septic shock rats. METHODS: The septic shock model was made in rats by caecal ligation and puncture. The intima, media and adventitia of the rat aorta were separated. NO production (NO - 2) , nitric oxide synthase(NOS) activity and L-arginine (L-Arg) transport were measured, separately. Inducible NOS (iNOS) distribution was detected by immunohistochemistry. RESULTS: Both in early and late stage of septic shock, NO - 2 from the intima was decreased by 66.1% and 78.9%( P

OBJECTIVETo evaluate the differences in the autophagy activity of alveolar macrophages between patients with different stages of coal workers' pneumoconiosis (CWP).

METHODSA total of 116 coal workers were investigated in the field. Their lung lavage fluid was collected and purified to obtain alveolar macrophages. The morphological characteristics of autophagy were observed by transmission electron microscopy. The expression of autophagy marker (LC3) and autophagy regulators (Beclin1, mTOR, and p-mTOR) was measured by Western blot. The autophagy activity of alveolar macrophages was compared between dust-exposed subjects and patients with stage I, II, and III CWP.

RESULTSThe autophagy activity of alveolar macrophages differed between patients with different stages of CWP, according to transmission electron microscopy. Patients with stage II CWP had significantly higher protein expression of LC3 II/I and Beclin1 in pulmonary macrophages than those with stage ICWP (P < 0.05); patients with stage III CWP had significantly lower protein expression of LC3 II/I and Beclin1 in pulmonary macrophages than those with stage II CWP (P < 0.05), but had significantly higher protein expression of LC3 II/I and Beclin1 than those with stage I CWP (P < 0.05); patients with stage II CWP had a significantly higher protein expression of Beclin1 than the dust-exposed subjects (P < 0.05). Patients with stage II CWP had significantly lower expression of mTOR and p-mTOR in pulmonary macrophages than the dust-exposed subjects and those with stage I CWP (P < 0.05), while patients with stage III CWP had significantly higher expression of mTOR and p-mTOR than those with stage II CWP (P < 0.05).

CONCLUSIONThe autophagy activity of alveolar macrophages varies between patients with different stages of CWP.

Anthracosis ; pathology ; Apoptosis Regulatory Proteins ; metabolism ; Autophagy ; Beclin-1 ; Biomarkers ; Bronchoalveolar Lavage Fluid ; Coal ; Coal Mining ; Dust ; Humans ; Macrophages, Alveolar ; pathology ; Membrane Proteins ; metabolism ; Microtubule-Associated Proteins ; metabolism ; Occupational Exposure ; Pneumoconiosis ; pathology

Objective: To explore the influence of heat and noise exposure on the risk of hypertension in workers,and to provide evidence for prevention of hypertension in occupational population. Methods: Cluster sampling method was used to recruit 2 130 steel workers from four factories（north iron-making,long steel,cold steel and power department）of some steel company. A cross-sectional study was conducted to collect physical examination results,heat and noise exposure. Logistic regression models were used to analyze the effects of noise,heat and their interaction on hypertension. Results: Totally 1 971 valid questionnaires were collected,and the response rate was 92.54%. There were 654 workers suffering from hypertension,with a prevalence rate of 33.18%. There were 1 006 workers exposed to noise,accounting for 51.04%;and 853 workers exposed to heat,accounting for 43.28%. The prevalence rates of hypertension in workers exposed to noise and heat were higher than those in workers without the above exposure（P<0.05）. The prevalence rates of hypertension increased with the increase of age and working years（P<0.05）. The results of multivariate logistic regression analysis showed that noise（OR=1.711,95%CI：1.380-2.121）,heat（OR=1.721,95%CI：1.394-2.125）were risk factors for hypertension;the interaction between noise and heat on hypertension was not statistically significant（P>0.05）,while the interaction between noise and age（OR=1.086,95%CI：1.057-1.115）,between heat and age（OR=1.087,95%CI：1.059-1.115）both increased the risk of hypertension. Conclusion Occupational exposure to heat and noise are risk factors for hypertension. These two occupational hazards also interact with age,which can increase the risk of hypertension in workers.

OBJECTIVE: To study the mechanism of tumor necrosis factor( TNF)-α and its receptor( TNFR) signal transduction pathways in regulating cell apoptosis of alveolar macrophage( AM) in coal workers' pneumoconiosis( CWP).METHODS: Twenty-four coal workers with pneumoconiosis at stage Ⅰ were selected as CWP group and four observation subjects exposed to coal were chosen as observation group by using simple random sampling method. The bronchoalveolar lavage fluids of whole-lung lavage of two groups were collected. AMs were separated and purified. Then they were divided into 6 groups: a control group,a superoxide dismutase( SOD) group,a TNF/TNFR group,an anti-TNF-α antibody group,a Caspase-8 suppression group and a nuclear factor-κB( NF-κB) suppression group. The AMs of 6 groups with corresponding treatment were cultivated. After 24 hours,the cells were harvested and proteins extracted. The relative expression of TNF-α,TNFR1,TNFR2,Caspase-8,Caspase-3,NF-κB P50 and NF-κB P65 protein was detected by Western blotting. RESULTS: The protein relative expression of TNF-α,TNFR2,Caspase-8,Caspase-3,NF-κB P50 and NF-κB P65 in CWP group was significantly higher than those in the observation group( P < 0. 05). The protein relative expression of TNF-α,TNFR1,Caspase-8,Caspase-3 and NF-κB P50 in the TNF/TNFR group and the anti-TNF-αantibody group was lower than that of the control group( P < 0. 05). The above indexes in the anti-TNF-α antibody group were lower than that of the NF-κB suppression group( P < 0. 05). The protein relative expression of TNFR1,Caspase-8and Caspase-3 in the TNF/TNFR group was higher than that of the SOD group and the Caspase-8 suppression group( P <0. 05). The protein relative expression of TNFR1,Caspase-8 and NF-κB P50 in the TNF/TNFR group was lower than that of the NF-κB suppression group( P < 0. 05). Among the CWP patients,the relative expression of TNFR2 and NF-κB P65 in the TNF/TNFR group was lower than that of the control group( P < 0. 05),and higher than that of the SOD group( P <0. 05). CONCLUSION: AM apoptosis mediated by TNF-α/TNFR/NF-κB signal transduction pathway plays an important role in the occurrence and development of CWP. The TNF-α/TNFR/NF-κB signal transduction pathways inhibited or blocked at different stages can affect the expression of proteins related to AM apoptosis.

OBJECTIVE: To explore the relationship between Effort-Reward Imbalance(ERI) and insomnia using structural equation modeling. METHODS: A total of 5 769 steel workers from an iron and steel company were selected as study objects by convenient sampling method. The Effort-Reward Imbalance Scale and Five-Item Athens Insomnia Scale were used to investigate their ERI and insomnia respectively. A structural equation modeling was constructed to analyze the relationship between ERI and insomnia. RESULTS: The scores of work effort and internal investment were positively correlated with the score of insomnia [the Spearman correlation coefficient(r_S) were 0.127 and 0.122 respectively, P<0.01]. Work reward scores were negatively correlated with the score of insomnia(r_S=-0.126, P<0.01). We successfully construct a structural equation model between ERI and insomnia in steel workers. According to this model, work effort, work reward and internal investment had direct effect on insomnia [the standardized path coefficient(β) were 0.065,-0.067 and 0.091 respectively, P<0.05]. Work effort and work reward have direct effect on insomnia(the β were 0.048 and-0.010 respectively, P<0.05). CONCLUSION: ERI increases the risk of insomnia. Both effort and internal investment have positive effect on insomnia, while reward has negative effect on insomnia.

OBJECTIVE: To investigate the relationship between the sleep duration on peak melatonin secretion and renal function injury in steel workers. METHODS: A judgment sampling method was used to select 7 655 steel workers in a steel production department for health examination and questionnaire survey, and the relationship between renal function injury and non-peak sleep time(equivalent to the reduction of sleep duration on peak melatonin secretion) was analyzed using restriction cubic spline(RCS) model and multi-factor logistic regression. RESULTS: The detection rate of renal injury in the study subjects was 14.5%(1 110/7 655). RCS model analysis results showed that there was a linear dose-response relationship between non-peak sleep time and renal injury(overall correlation test χ~2=16.85, P<0.01, nonlinear test χ~2=3.70, P>0.05). Multivariate logistic regression analysis results showed that the workers of non-peak sleep time more than or equal to 4 515-day had higher risk of renal function injury than the workers of non-peak sleep time less than 4 515-day(P<0.05), with odds ratio and 95% confidence interval of 1.4(1.2-1.7), after adjustment for the potential influencing factors such as individual factors and occupational factors. CONCLUSION: Reduction of peak melatonin secretion sleep duration is correlated with renal function injury in steel workers.

OBJECTIVE: To analyze the effect of occupational stress on abnormity of serum total cholesterol and triglyceride in male steel workers. METHODS: A total of 3 957 male steel workers from an iron and steel group company were selected as study objects by judgment sampling method. Occupational stress was measured by the Chinese version of Job Content Questionnaire. The serum total cholesterol and triglyceride levels were measured using fasting venous blood. RESULTS: Among the 3 957 workers,the detection rate of occupational stress was 56. 8%,and 55. 0% of them showed high social support. The abnormal rates of total cholesterol and triglyceride were 21. 8% and 40. 9%,respectively. The multivariate logistic regression analysis showed that workers with high social support had high risk of abnormal total cholesterol and abnormal triglyceride than workers with low social support( P < 0. 05) after adjusting for confounding factors such as age,education level,marital status,body mass index,smoking and drinking alcohol,tea. The odds ratio of abnormal total cholesterol in occupational stress workers was 1. 17 times of that of non-occupational stress workers. No association was found between occupational stress and abnormal triglyceride( P > 0. 05). CONCLUSION: Occupational stress may be associated with abnormity of total cholesterol in male steel workers. Social support is an important influences factor to the abnormity of total cholesterol and triglyceride in male steel workers.

OBJECTIVE: To explore the effect of occupational high temperature exposure on type 2 diabetes( T2 DM) in male steel workers. METHODS: A cluster random sampling method was used to select 684 male steel workers,who exposed to occupational high temperature in a steel enterprise in Tangshan City,as the high temperature group,and 1 153 male steel workers without occupational high temperature exposure as the control group. The high temperature level of workers in these two groups was measured. The cumulative exposure( CE) of high temperature was calculated,and occupational health exam was performed. The multivariate logistic regression analysis and restricted cubic splines were used to analyze the relationship between high temperature CE and T2 DM. RESULTS: The prevalence of T2 DM in high-temperature group was higher than that in the control group( 13. 0% vs 7. 9%,P < 0. 05). The multivariate logistic regression analysis results showed that the risk of T2 DM in the high temperature group was higher than that in the control group after adjusting for age,body mass index,smoking,drinking,physical exercise and parents with diabetes( P < 0. 05). The 95% confidence interval was 1. 65( 1. 17-2. 33). Restricted cubic spline analysis showed that the high temperature CE was correlated with the prevalence of T2 DM in workers( P < 0. 01) and showed a linear correlation( nonlinearity test,P > 0. 05). CONCLUSION: Occupational high temperature exposure is associated with the occurrence of T2 DM in male steel workers. The male steel workers with high temperature CE show high prevalence of T2 DM risk.

OBJECTIVE: To explore the relationship between shift work and type 2 diabetes in oil workers. METHODS: A total of 2 666 oil workers in an oil group were selected as the study subjects using the typical sampling method. Questionnaire survey was conducted by a self-designed Questionnaire of Health Assessment for Oil Workers, and blood glucose level was measure. RESULTS: The prevalence of type 2 diabetes in the study subjects was 10.1%(268/2 666). The prevalence of type 2 diabetes in shift workers was higher than that in non-shift workers(13.1% vs 6.0%, P<0.01). After adjusting for the influence of confounding factors such as gender, body mass index, family history of diabetes, history of hypertension, history of hyperlipidemia, and physical exercise, multivariate logistic regression analysis results show that the longer the shift work length, the higher the risk of developing type 2 diabetes(P<0.01), workers with shift work(3 shifts in a day, 2 shifts operating) had a higher risk of type 2 diabetes than that in non-shift workers(P<0.05). CONCLUSION: The shift work length and shift workers with 3 shifts in a day, 2 shifts operating can increase the risk of type 2 diabetes in oil workers.